CONTROL CHANNELS ARE KEY TO ACCELERATING THE DOWNLINK

w i r e l e s s . i o p . o r g T E C H N I C A L I N S I G H T F O R W I R E L E S S P R O F E S S I O N A L S

F E B R U A R Y / M A R C H 2 0 0 5 I S S U E 3 7

CONTROL CHANNELS ARE KEY TO ACCELERATING THE DOWNLINK

HSDPA3G standards battle ragesEDGE benefits from rethinkMobile broadband comes of age

http://wireless.iop.org

_______________ like never before.

To learn more about our industry-leading mobile technology:Visit us at 3GSM World Congress at Hall 2, Stand D60See us online at www.analog.com/processors

Features. Flexibility. First-to-market.Analog Devices Chipsets make innovative handsets happen.Question: how do you get the latest features—imaging, video, MMS, GPRS, E-GPRS,ringtones, and more—into your handset designs quickly, at optimal performance,for the best possible cost? Answer: the Analog Devices SoftFone® Platform.

The reasons are simple. The SoftFone RAM-based architecture lets you add features in software without hardware redesigns. Analog baseband processing includes allradio-interface, control, audio functions, and power-management on chip (with optionalstereo audio playback). The award-winning Othello® radio family gives you the lowest-cost radio section, with quad-band operation. And ADI’s Nova Wireless Engine reference design helps you get your first model to market fast.

It’s a total solution. For totally revolutionary mobile technology.And it’s only from Analog Devices.

SoftFone® and Othello® are registered trademarks of Analog Devices, Inc.

http://www.analog.com/processors

U P F R O N T 5

S T A N D A R D S 6

L E A D E R 8

A N A LY S I S 1 1Handsets: Configuration is affecting data servicesModems: Machine-to-machine has great potentialBackhaul: Free-space optics offer network security3G standards: 2005 will be a turning point

O P I N I O N 1 6Mark PaxmanWill peer-to-peer networks provide greater bandwidth,or will they put operators in another fine mesh?

D A T A S E R V I C E S 1 9Network operating system will unite telecoms and ITOperators and the IT industry are joining forces todevelop a carrier-network operating system.

D O W N L I N K 2 3New control channels boost HSDPA performanceHSDPA employs variable modulation and codingschemes to adapt to changes in downlink signal.

H A N D S E T S 2 7Complexity increases as EDGE bridges thegeneration gapWhile EDGE radios contain elements of both GSMand UMTS technology, GSM/EDGE/W-CDMAintegration can benefit from a radical rethink.

P O C 3 1Push-to-talk reaps the benefits of standardizationOperators must encourage standardization in order toenjoy the financial rewards of providing PTT services.

R F - O V E R - F I B R E 3 5Demand for indoor coverage drives radio-over-fibreFibre-optic cable will ensure that cellular voice anddata services are available throughout large buildings.

P R O D U C T F O C U S 3 7DSP takes GPS to a new level

P R O D U C T S 3 83GSM preview

T H E F U T U R E 4 2Wireless broadband comes of ageNortel’s John Hoadley believes that the cellularindustry is moving rapidly towards mobile broadband.

3C O N T E N T S

FEBRUARY/MARCH 2005ISSUE 37

Institute of Physics Publishing Ltd,Dirac House, Temple Back, BristolBS1 6BE, UK.Tel: +44 (0)117 929 7481Editorial fax: +44 (0)117 925 1942Advertising fax: +44 (0)117 930 1178Web: wireless.iop.orgE-mail: [email protected]

EDITORIALEditor: Hamish Johnston;[email protected] production editor: Kerry BristowArt director: Andrew GiaquintoTechnical illustrator: Alison Tovey

ADVERTISINGSales manager: Dan Huckle; [email protected] advertising manager: Paul Turp;[email protected] co-ordinator: Jayne Boulton;[email protected] production editor: Tanwen Haf

MARKETING AND CIRCULATIONProduct manager: Angela Peck;[email protected]

PUBLISHERSarah Chilcott; [email protected]

PUBLISHING DIRECTORRichard Roe

ISSN 1471-3888

SUBSCRIPTIONSFree to qualifying readers (see subscription cardenclosed or register online at the above Webaddress). Subscriptions £96/7139 ($147 in theUS and Canada) for six issues to readers who donot meet qualifying criteria. Orders to WirelessEurope, IOPP Magazines, WDIS Ltd, Units 12 &13, Cranleigh Gardens Industrial Estate, Southall,Middlesex UB1 2DB, UK. Tel: +44 (0)20 86067518; fax: +44 (0)20 8606 7303; e-mail:[email protected]

©2005 IOP Publishing Ltd

The contents of Wireless Europe do not representthe views or policies of the Institute of Physics, itscouncil or officers unless so identified.

Printed by Warners (Midlands) plc, Bourne,Lincolnshire, UK.

BBPPAA WWoorrllddwwiiddee BBuussiinneessss PPuubblliiccaattiioonn AAuuddiittmembership applied for January 2005

w i r e l e s s e u r o p e wire less. iop.org F e b r u a r y / M a r c h 2 0 0 5

Multiple beams dodge birds and raindrops. p15.

John Hoadley is keen on mobile broadband. p42.

PTT users will benefit from standardization. p31.

On the cover:HSDPA offers higherdata rates, but at aprice. p23.Image: Vic LeBillon.



mailto:[email protected]








See us at3GSMStand F28Hall 2

Stream if you want to go faster!HSDPA Solutions enabling 3G rolloutHSDPA packet-based data services in W-CDMA will enable the mobile community to provide many of the applicationsthat will drive the success of the technology.

Building consumer confidence often proves tricky. Success or failure relies on products and services delivering each andevery time as the industry looks to improve customer experience and retention through quality of service.

Anritsu, at the heart of 3G since its conception, provides solutions enabling developers, manufactures and serviceproviders to design, prove technology and products long before they go to market. At the heart of this product portfolio isthe NEW MD8480C signaling tester which empowers designers to develop tomorrow’s HSDPA solutions today.

For more information on Anritsu's HSDPA test solutions and other systems for conformance, R&D, manufacturing, maintenance and servicing for mobile technology call +44 (0)1582 433433 or email [email protected]

www.eu.anritsu.com

http://www.eu.anritsu.com

5U P F R O N T

An ultra wideband (UWB) wire-less link has achieved a data rateof 667 Mbit/s. The transmissionwas made using UWB technol-ogy developed by US-basedPulse~LINK. Claimed to be thefastest UWB transmission ever,the data rate was measured afterforward correction error wasapplied to the data.

“Our actual over-the-air datarate at present is 1.3 Gbit/s,” saidPulse~LINK’s chief technologyofficer John Santhoff. He ex-plained that further optimizationof the technology will bring thecorrected data rate into the giga-hertz range.

Pulse~LINK expects to releasea UWB RFIC shortly, and is alsodeveloping a new forward error

correction technology that is saidto be more efficient at extremelyhigh data rates. The companyexpects that its UWB devices willreplace cables in video entertain-

ment systems and also in wirelesslocal-area networks (WLANs).The technology could also beused to transmit data over arange of wireline networks,including power lines.

• NTT DoCoMo has con-firmed that it achieved a down-link data rate of 1 Gbit/s using anair interface intended for use in4G cellular networks. The Japan-ese operator said that a variablespreading factor spread OFDMair interface with multiple-input,multiple-output antenna diver-sity was used in a laboratorydemonstration performed inAugust 2004. The system had a100 MHz bandwidth. DoCoMoexpects to begin field trials of thetechnology in 2005.


UWB link hits 667 Mbit/s data rate

Pulse~LINK’s John Santhoff looks forwardto corrected data rates in excess of 1 Gbit/sfrom the company’s UWB technology.

Canada’s Nortel claims to havemade the first HSDPA call usinga commercial UMTS base sta-tion. The call was made using thecompany’s network equipment(including a software upgrade toHSDPA), and received by a hand-set using Qualcomm’s MSM6275HSDPA chipset. The chipset,which also supports GSM andEDGE, is currently available on asampling basis.

The demonstration was per-formed at Nortel’s Chateaufortfacility in France, and involved alive air connection to a movingautomobile to demonstrate thestability of the connection in areal-world environment.

Nortel has joined forces withthe 3G operator mmO2 todeploy HSDPA in mmO2’sUMTS networks in Europe.

HSDPA call uses commercial base station

US-based Qualcomm’s MSM6275 chipsethas completed an HSDPA call with a 3Gbase station from Nortel.

Cellular operators in industrial-ized counties are focusing theirattention on increasing thecapacity of existing infrastructurerather than installing new equip-ment, says a report from US-based ABI Research. Accordingto analyst Brian Pellegrini,spending on new equipment roseslightly in 2004, but network

operators remain very reluctantto invest in new infrastructure.

Pellegrini concedes that 3Groll-out has boosted infrastruc-ture spending, but cautioned that“[operators] are still afraid of over-extending, and the biggest factordriving down spending is thehigh cost of base stations”.

“Compared to buying base sta-

tions, increasing capacity ischeap,” said Pelligrini. Most basestations can be upgraded withsoftware, rather than much moreexpensive hardware. In addition,Pelligrini believes that operatorsare finding ways of increasingrevenue by developing new ser-vices that do not require addi-tional infrastructure. He predictsthat poor infrastructure sales willlead to “some consolidation inthe industry between now and

the end of the decade”.Another analyst at ABI has

described the market for RFpower amplifiers and powerdevices as being “in a tenuousstate”. Lance Wilson predicts thatthe current slump in sales willcontinue throughout 2005. Healso identified 3G as “the onebright spot”, but conceded it“cannot provide enough turnoverin revenues of in-shipped units toturn the market segment around”.

China Putian and Nortel are toform a new company to develop,manufacture and market 3Gequipment in China. CalledPutian-Nortel Networks, thefirm will be launched in mid-2005 and is expected to be head-quartered in Wuhan. ChinaPutian will own 51% of the jointventure, with Canada’s Nortelowning the remainder.

China Putian’s president XingWei said that the deal will “sig-nificantly accelerate the interna-tionalization of our 3G offerings”.Nortel’s president Bill Owenssaid that the joint venture will

“strengthen our capability tooffer industry-leading solutionsfor our customers and newprospects in China”.

China Putian is developingproducts for the TD-SCDMA3G standard, which is expectedto be used in China.

Nortel in Chinese3G partnership

Nortel’s president Bill Owens looks forwardto more business in China thanks to a newjoint venture with China Putian.

Cellular operators focus on capacity

Portugal Telecom and ZTE havesigned a memorandum of under-standing that covers R&D activ-ities in Europe and China. ThePortuguese mobile and fixed-lineoperator and Chinese telecomsequipment supplier will alsojointly bid on tenders.

Portugal Telecom’s chief execu-tive Miguel Horta e Costa saidthat the agreement will help thecompany to export products andservices to China.

The agreement will give ZTEaccess to markets where PortugalTelecom operates. ZTE alsohopes that its relationship withPortugal Telecom will open doorsto participation in Europe-basedinternational R&D projects.

ZTE and PortugalTelecom sign deal


6 S T A N D A R D S

F e b r u a r y / M a r c h 2 0 0 5 wire less. iop.org w i r e l e s s e u r o p e

The Third Generation PartnershipProject has released performancespecifications for the implemen-tation of assisted global position-ing system (A-GPS) technologyon UMTS handsets. The specifi-cations define general test condi-tions for GPS signals and handsetlocation, as well as test condi-tions for the UMTS network.

Also defined are a wide rangeof performance requirements forA-GPS implementation such asmeasurement parameters forhandset-based and handset-assisted A-GPS. Sensitivity andaccuracy requirements are pro-vided in addition to the mini-mum requirements for dynamicrange. Performance requirementsin the presence of multipath sig-nals are defined as well as the useof A-GPS while on the movewith periodic position updates.

The specifications were writtenby the test and measurementvendor Spirent, with input fromthe cellular industry. The com-

pany’s director of applicationsengineering, Nigel Wright, toldWireless Europe: “It will be quite awhile before formal A-GPS con-formance testing begins.” This isbecause the test cases must firstbe implemented on the appropri-ate test equipment, and then thetest systems must be approved byan appropriate industry bodysuch as the Global CertificationForum. Spirent has alreadyimplemented A-GPS test cases inits UMTS Location Test System(ULTS), which will debut thismonth at the 3GSM WorldCongress in Cannes, France.

Wright believes that Europeanoperators have been cautiousregarding A-GPS and the loca-tion-based services (LBS) that thetechnology can enable. Whilesome concerns linger over thedeployment of A-GPS in Europe,Wright believes that operators areholding back for business rea-sons. “Most A-GPS in Europewill be used for commercial data

services, and operators are con-cerned that the provision ofhandset location over the Internetcould allow third parties to pro-vide LBS, robbing operators ofrevenue,” explained Wright.

The Open Mobile Alliance isaddressing this issue through thedevelopment of a secure userplane wrapper for A-GPS, whichwould allow operators to controllocation information. Wrightsaid that this project is delayed byabout one year, which has damp-ened enthusiasm for A-GPS.

While it is very likely that asimilar specification for GSMwill be created, Wright com-mented that there is very littleinterest from operators. Whilethis may be down to the techni-cal challenges of implementingA-GPS on GSM, Wright believesthat European operators arereserving A-GPS to their 3G net-works because it could be used asa differentiating technology tolure subscribers away from 2G.

3GPP releases A-GPS performancespecifications for UMTS handsets

The European Conference ofPostal and TelecommunicationsAdministrations (CEPT) has rec-ommended that the 2500–2690 MHz band should bereserved for use by licensedUMTS services. The spectrum isexpected to be licensed in 2008.

The CEPT has recommendedthat the 2500–2570 and 2620–2690 MHz bands should bepaired for UMTS FDD deploy-ment with frequency blocks inmultiples of 5 MHz. The 2570–2620 MHz band has been identi-fied with either UMTS TDDservices or as a FDD downlinkband. The CEPT stated that spe-cific details regarding the widthof guard bands and licensingconditions should be defined byindividual countries.

The decision has beenapplauded by the UMTS Forum,which represents the operatorcommunity. Its chairman Jean-Pierre Bienaimé said: “Additionalfrequencies in the 2.6 GHz rangewill help to assure the long-termmarket success of UMTS ser-vices, while allowing for a naturalevolution of the technology”.The 1900–2170 MHz band iscurrently reserved for UMTS inmost European countries.

Europe harmonizesUMTS at 2.6 GHz

The UMTS Forum’s chairman Jean-PierreBienaimé believes that additionalspectrum will assure the long-termsuccess of UMTS services.

Roke Manor Research has openeda facility for the testing of mobilephones according to standardsdefined by the Cellular Telecom-munications and Internet Associ-ation (CTIA). The UK facilitycan perform over-the-air (OTA)testing, which must be donebefore a handset can be certifiedfor use in the US. This is the sixthfacility worldwide, and the secondin Europe to be accredited by theUS-based CTIA for OTA testing.

The test chamber was providedby US-based ETS-Lindgren, andthe test system and software wassupplied by UK-based EMV.While the CTIA is currently theonly organization requiring OTAhandset testing, Martin Wiles,

senior RF engineer at ETS-Lindgren, explained that similarrequirements could be intro-duced in Europe and Asia in thenear future. He also observedthat “most major [handset] man-ufacturers produce products forthe global market, so CTIA com-pliance testing is becoming a

matter of course”.Roger Hopper, principal group

manager at Roke Manor, said:“We currently have six projectsundergoing testing in the cham-ber and [we] are in the process ofbidding for a number of highprofile contracts.” Roke Manor isowned by Siemens of Germany.

OTA test centre issecond in Europe

The Roke Manor chamber is one of six facilities accredited by the CTIA for OTA testing.


http://www.spirentcom.com/wireless

8 L E A D E R


There is little doubt that high-speed downlink packetaccess (HSDPA) will be one of the hottest topics onthe agenda at 3GSM in Cannes. HSDPA boostsUMTS data rates in much the same way that EDGEaccelerates GSM, and theories abound as to whyoperators appear to be obsessed with this 3.5Gtechnology before their 3G networks have garneredsignificant subscriber numbers.

On page 42, Nortel’s John Hoadley tells me that thepresence of cdma2000 1X EV-DO networks in Koreaand the US is focusing attention on HSDPA as a wayfor UMTS operators to keep pace with their CDMArivals. Meanwhile in Europe, where EV-DO is not athreat, some industry observers such as Stirling Essex ofUbiNetics believe that the region’s UMTS networkswill be a runaway success in 2005, and that HSDPAwill be deployed in 2006 to address capacity shortages.

Operators and consumers will ultimately benefitfrom the accelerated development of HSDPA, but it isimportant to remember that there are still significantchallenges associated with the development anddelivery of data services. On page 11, Tim De Luca-Smith explains why handset configuration problemsare slowing the uptake of new services, and argues thatover-the-air configuration is the way forward. At thenetwork level, much work needs to be done to ensurethat new services can be deployed in a timely manner.On page 19, Kieran Dalton explains the need for a“network operating system”, which he claims will dofor mobile data services what UNIX and DOS did foran emerging computer industry several decades ago.

HSDPA challengesWhile HSDPA can offer higher data rates, these comeat a price. On page 23, Faris Muhammad navigatesthrough myriad new control channels and modulationschemes that ensure HSDPA achieves the highestpossible data rate. And like EDGE before it, there areconcerns about whether HSDPA can deliver 10 Mbit/sdata rates throughout a UMTS coverage area without aradical reoptimization of the radio network. Whilethese challenges are real, it’s probably best not to loseany sleep over them – at least until UMTS networksbegin to attract significant numbers of subscribers whoare willing to pay for high-bandwidth services.

Hamish Johnston, Editor

Mobile broadband boomE D I T O R I A L

Huawei breaks into western EuropeHuawei Technologies is to supply UMTS infrastructure equipment to theNetherlands-based operator Telfort. The deal is a western European first forHuawei of China, and covers both core and radio-access network equipmentfor Telfort’s national network. Huawei will also help Telfort to develop mobileservices, and will establish a research and development centre in Amsterdamthat will focus on end-user applications.

Guard bands to be released for GSMThe UK telecoms regulator Ofcom has called for the release of spectrum inthe guard bands between DECT and GSM services. Ofcom has recommendedthat the spectrum be used for wireless communications such as GSM at powerlevels of less than 200 mW. This would involve the use of picocellular basestations with typical ranges of 200 m outdoors and 50 m indoors. Serviceswould be compatible with existing GSM handsets. The bands will be at 1781.7–1785 MHz and 1876.7–1880 MHz, and could be made available this year.

UbiNetics predicts early HSDPA roll-outMany 3G networks in Europe will reach their capacity limits by the end of thisyear, causing operators to accelerate the roll-out of the high-speed downlinkpacket access (HSDPA) upgrade to UMTS, predicts the UK-based wirelesstechnology firm UbiNetics. “There is little doubt in my mind that HSDPA willbe ready for widespread deployment in Europe within 12 months,” saidStirling Essex, the company’s head of strategic marketing. Essex added thatHSDPA trials performed by the Japanese operator NTT DoCoMo indicate thatHSDPA is “relatively easy to deploy”.

TD-SCDMA video phone unveiled in ChinaDatang Mobile has demonstrated a video phone that operates on the time-division synchronous CDMA (TD-SCDMA) 3G standard. Claimed to be theworld’s first TD-SCDMA video phone, the handset supports end-to-end videotelephony at 15 frame/s on a 64 kbit/s wireless data link. It employs a videotelephony stack from US-based Dilithium Networks. TD-SCDMA networks areexpected to be licensed in China, where the handset maker Datang is based.

Cognitive radio groups expandTwo new industry groups focusing on cognitive radio have been launched bythe Software Defined Radio (SDR) Forum. The Cognitive Radio Working Groupwill provide guidance and standards for the development and implementationof SDR technologies. The special interest group will focus on the businessand regulatory issues facing the emerging cognitive radio industry. Accordingto Bruce Fette, Technical Committee Chair of the SDR Forum, “SDR is thebest solution to address the adaptability component of cognitive radio.”

Ericsson joins WiMAX ForumEricsson is the latest major cellular equipment maker to join the WiMAXForum, which is an industry organization that promotes the development ofthe IEEE 802.16 and ETSI HiperMAN wireless broadband standards under theWiMAX banner. The technology could be used to provide fixed and nomadichigh-speed data services, and some in the industry believe that it couldcomplement or even compete with 3G data services. WiMAX could also beused to backhaul cellular networks, particularly micro- and nanocellular basestations. The Swedish equipment vendor plans to offer WiMAX products aspart of its Public Ethernet product line and as a complement to wirelinedigital subscriber line (DSL) equipment. The company has stated that WiMAX“targets a different [market] segment than 3G”, and that it does not believethat the technology is appropriate for mobile applications.

N E W S I N B R I E F


http://www.vectron.com

http://www.speag.com

1 1A N A LY S I S


Handset configuration is becoming a realchallenge for the cellular industry. Configur-ation-related problems are often to blame forlong delays between the deployment of newservices such as MMS and the generation ofnew revenue. While advancements in SIMcard and terminal technology have paved theway for advanced data services, it is still verydifficult for network operators to ensure thattheir many subscriber devices are configuredto access the latest mobile services.

Configuration is a challenge becausemobile phone ownership is in a constant stateof flux. Users are changing handsets more fre-quently than ever, and many people havemore than one terminal. This makes existingmethods of device configuration – such aspreconfiguration of handsets by operators –inappropriate. A growing number of hand-sets are not purchased from operator-ownedretail outlets, and are not preconfigured.Handsets are often being taken from one net-work to another by churning customers, orswapped between friends and family.

If a handset is not preconfigured, a sub-scriber must contact the operator and requestthe relevant settings to use the latest services.In the absence of must-have applications, thechances of this happening are slim. As aresult, a substantial proportion of handsetson any given network are unable to access afull range of services.

Several European operators have developednew automatic device-configuration plat-forms, which promise to increase the per-centage of correctly configured devices in anetwork and reduce the costs associated withpreconfiguration. Automatic device detec-tion and configuration allows an operator toidentify remotely individual device types –and their capabilities – as they become activeon the network. It is then possible to send thecorrect settings to a device over the air, elim-inating the need for end-users to configuretheir own handsets.

Automatic device configuration schemesmust first detect when a subscriber uses their

SIM in a new terminal – an event called a“terminal switch”. There are two indepen-dent methods for doing this: one employs anetwork-based mechanism and the other usesa SIM-based application.

SIM-based terminal switch detection usessoftware resident on the SIM to identify itshost terminal. This can be triggered accordingto predefined rules – on initial power-up oron a weekly basis. Once the application hasidentified a new terminal, it submits the infor-mation over the air to the operator. Network-based terminal switch detection requires aspecific trigger from within the operator’sbearer network. This trigger can be activatedby network events such as a device attachingto the network. It “listens” and extracts infor-mation about the subscriber and handset. Itthen supplies the automatic device configu-ration platform with terminal switch infor-mation according, again, to predefined rules.

Once a terminal switch has been deter-mined, the information regarding the exactdevice type is passed through a databasecalled the terminal capabilities repository todetermine the capabilities of the handset.This ensures that the network provides thehandset with the relevant settings and ser-

vices based on factors such as the device’sGPRS capabilities and the WAP versiondelivery protocol to be used.

The provisioning element of the platformis then free to deliver appropriate settings,such as WAP, MMS, e-mail and Internet set-tings, over the air. This is done using a pro-tocol that is appropriate for the handset –OMA, SyncML, Openwave or device-specificprotocols, for example.

Both terminal-switch detection mecha-nisms go some way towards creating a devicemanagement infrastructure that encompassesthe entire lifecycle of a mobile subscription.In the early days of GSM, a mobile subscrip-tion was relatively static, but faster handsetdevelopment cycles and the operators’ com-mercial need to deploy the latest advancedservices mean that subscription managementis a growing challenge.

The slow growth of services such as MMShighlights the need for over-the-air deviceconfiguration. While much of the blame forthe slow uptake of MMS has been placed onpoor interoperability, surprisingly little atten-tion has been given to the issue of device con-figuration and its impact on service usage.Conversely, the success of SMS has beenlargely attributed to its ubiquitous nature,requiring no manual input of service settings.

As subscriber figures in Europe plateau,operators are putting more emphasis on cus-tomer retention rather than acquisition. Byremoving the complexities of handset config-uration, customers are granted immediateaccess to the operator’s portfolio of revenue-generating services. There is no need tocontact customer care or to follow set-upprocedures on the operator’s/handset manu-facturer’s website. This form of customer sat-isfaction is, of course, key for building loyaltyand brand. By simplifying access to interest-ing and relevant services, service usage – andrevenue – can only go one way. ■

Tim De Luca-Smith is communicationsmanager at Sweden-based SmartTrust.

Over-the-air protocols simplifyhandset configuration

H A N D S E T S

GSMnetwork

automaticdevice detection

over-the-airprovisioning

new terminaldetection filter

SIM or network-basedprovisioning of settingsand transport server

When a new handset-and-SIM combination is detected,the relevant information is used to determine the devicecapabilities. The necessary configuration settings canthen be sent over the air to the device.

Tim De Luca-Smith argues that the complexities of device configuration are affecting the growth of data services.


http://www.renesas.com

1 3A N A LY S I S


Network operators are beginning to realizethe commercial benefits of offering data-onlymachine-to-machine (M2M) communica-tion services in addition to traditional voice-and-data services. Specific data-only tariffsare now being introduced, which is a signifi-cant shift from the situation two years ago,when data-only communication was hardlyeven heard of, let alone considered somethingworth investing in.

The growing acceptance of GPRS technol-ogy is one reason why things have changed.Until recently, subscribers have been scepticalof GPRS or misunderstood its potential. Inreality, GPRS is ideal for any type of wirelessdata communication – including M2M.

For example, GPRS technology is perfectlysuited to point-of-sale equipment such as acredit card terminal. Credit-card transactionsinvolve the exchange of small amounts ofdata, which GPRS is able to handle cost-effectively. The terminal can be fully mobileinstead of tied to a telephone line, and unlikecurrent systems that use dial-up modems,GPRS is always on, allowing constant andrapid communication.

Saving moneyIn the past, data and GPRS services werealways tied onto the back of voice SIM cards,giving the impression to customers that usingGPRS is expensive. In actual fact, a monthlysubscription to a data-only GPRS serviceworks out at roughly half the price of a voiceservice. The provision of data-only SIM cardsby leading operators such as Vodafone isspurring on the establishment of data-onlycellular services. Vodafone has gone as far asto set up a dedicated team in the UK toestablish a strategy for the development ofdata-only services.

The electronics industry has also woken up

to the potential of data-only cellular services.Indeed, manufacturers are beginning toinvest in redesign processes to incorporatetechnology such as GPRS into their equip-ment. This would allow manufacturers andusers to communicate with equipment suchas photocopiers, vending machines or secu-rity systems.

Investment in GPRS by companies outsidethe cellular communications industry reflectsa clear belief in those industry sectors thatGPRS is here to stay. After all, many of thesecompanies employ design and manufactur-ing processes that are much longer and morecostly than those in the mobile phone indus-try. Consequently, it is unlikely that theywould invest in embedding GPRS in theirproducts unless they saw a clear competitiveadvantage in doing so.

The range of possible M2M applications isstaggering: everything from security systemsand petrol stations to signage and electronicbillboards can all be updated, monitored andcontacted using GPRS. Road-traffic moni-toring will be transformed by equippingcameras with GPRS. These cameras can thenbe placed on any road, and still and videoimages can be transferred without the need ofa telephone line. Beyond western Europe,GPRS is ideal for offering M2M services indeveloping countries, which lack traditionalwire-line communications infrastructure.

Alpha Micro has been at the forefront of

embedding GPRS capabilities in M2Mapplications. The UK-based companyexploits the modem modules and expertise ofthe French mobile-phone maker Sagem tocreate a range of modems specifically forM2M communications. While M2M andwireless remote monitoring are definitely thetechnologies of the future, there is still moredevelopment needed to support GPRS,which throws up challenges to the develop-ment of new M2M modems.

Alpha Micro started using GPRS becauseit is a widely deployed and recognized stan-dard throughout the world, and because it isa cost-effective method of regularly sendingsmall amounts of data. On the downside,GPRS is not the best way to facilitate two-way communication. When an electronicdevice is fitted with a GPRS modem, it is notautomatically allocated with a permanentInternet protocol (IP) address by the mobileoperator. Once the modem begins to estab-lish a connection in preparation for transmit-ting data, it is then allocated with atemporary IP address. This makes it difficultfor the user to communicate at will with adevice in the field.

Speedy transmissionFortunately, by working closely with serviceproviders, it is now possible to allocate per-manent IP addresses to units in the field.This allows instant access to the device andenables emergency messages to be sent, forexample to stop trains or change traffic lights.This gives machines a real opportunity totalk to each other.

Looking towards the future, 3G networkswill expand the possibilities of M2M services.Data transmission will be even faster, and itwill be possible to send images and streamedmedia across cellular networks. With furtherinvestment and support from major networkoperators, the M2M industry has the poten-tial to be one of the largest growth marketsover the next 18 months. ■

Christos Papakyriacou is managing director ofUK-based Alpha Micro.

M O D E M S

Alpha Micro’s Trac M2M modem employs GPRS. WhileGPRS is ideal for transmitting small amounts of data, itdoes pose IP-related challenges to M2M developers.

GPRS leads the way for M2Mdata communications

The telecoms industry has finallywoken up to the potential for machine-to-machine data communications.Christos Papakyriacou explains howGPRS is driving things forward.


http://www.taconic-add.com

1 5A N A LY S I S


By Jim CadyOptical wireless systems based on free-spaceoptics (FSO) offer a secure and cost-effectiveway to backhaul networks, but the technol-ogy still suffers from a number of mythsregarding its performance. FSO is a little-understood technology, and the industry hasto contend with a range of questions such as:“do flying birds disrupt the signal?”; “canFSO systems work on swaying buildings?”;and “will falling snow block the beam?”

Modern FSO technology can trace itsroots back to the First World War, when mil-itary organizations needed secure communi-cations systems that did not require cable andthat were able to withstand intentional inter-ference or radio-jamming. It was importantin these military applications that commu-nications were secure and that the equipmentwas both portable and simple to set up. Theintroduction of the laser in the 1960senabled the transmission of digital informa-tion as pulses of light.

No-one quibbles over the ability of opticalwireless systems to provide high-capacitycommunications links at a low price-per-bitcost, and everyone agrees that the technologyis secure from severe weather, interference

and prying eyes. Instead, questions tend tofocus on network availability. As with anywireless technology, availability depends ona number of variables. The weather is a keyfactor for FSO-based systems, and this iswhere the myths persist.

Perhaps the most common misconceptionis that optical wireless systems do not per-form well in rainy weather. The truth is thatheavy rainfall – even tropical and monsoonconditions – do not disrupt communica-tions. Indeed, the larger the raindrop, the lessimpact it has on optical wireless signals.Optical wireless systems can remain opera-tional when subjected to driving rains, windand flying debris. This was demonstrated in2004 when Hurricane Charley struck CollierCounty in Florida. The category 4 hurricanedid not affect the county government’s opti-cal wireless system, which remained opera-tional throughout the entire ordeal.

Unlike rain, however, the minuscule water

particles that constitute fog can cause someproblems for FSO-based systems. Fog parti-cles act as millions of tiny mirrors that canreflect and scatter the optical signal. As aresult, fog can reduce the distance range ofoptical wireless systems, and dense fog canlimit the operation to less than 100 m.However, many installed systems have yet toexperience performance degradation due tofog, even in the worst conditions.

Incredibly, the myth that FSO-based sys-tems can be disrupted by flying birds – oreven “cook” them with laser beams – persists.In reality, today’s FSO-based systems incor-porate multiple beams, which transmit andreceive via as many as four separate paths.This makes it virtually impossible for a birdto block a signal, unless that bird is stationary– and the size of a human!

There is also a common belief that FSO-based systems fall prey to misalignment whenbuildings sway in the wind or expand andcontract during the hottest and coolest partsof the day and night. However, the introduc-tion of beam-tracking technologies and mul-tiple-beam architectures enables systems toeasily adjust to building movements that areundetectable to the eye.

A related misconception is that FSO-basedsystems cannot be mounted on cellular tow-ers. In reality, the same beam-tracking tech-nologies and multiple-beam architecturesallow a modern FSO system to easily adjustand realign during any movement by a towerstructure. ■

Jim Cady is president and chief executive ofUS-based LightPointe.

B A C K H A U L

An optical wireless system in the US capital: free-spaceoptics technology can operate even during the torrentialrain storms that are common in Washington, DC.

Optical wirelesssystems: sortingfacts from fiction

By Doug GrantThis year will be a turning point in the ongo-ing battle for market share among 3G stan-dards. Officially, there are five terrestrial airinterface standards, but only a few are gain-ing significant commercial traction.

European UMTS operators have recoveredfrom their financial woes and “buyer’s remorse”associated with high licence fees, and havedeployed a significant amount of W-CDMAinfrastructure. Heavily discounted 3G hand-sets are now being offered in a bid to moveusers from oversubscribed 2G networks, and

great strides have been made in reducing thecost, size and power consumption of thesehandsets. Industry analysts at The YankeeGroup predict that there will be about 60 mil-lion W-CDMA subscribers worldwide by theend of this year, making it clear that 3G tech-nology is becoming a true commercial system.

In North America, Japan and Korea, thecdma2000 1XRTT standard has been infor-mally given 3G status, after the original 3Gversion (cdma2000 3XRTT) proved too com-plex to pursue. Two versions of cdma2000 1Xhave been defined. EV-DV supports bothdata and voice traffic, while EV-DO is fordata only. Both systems are in the commer-cial stages of development. Cdma2000 3Gtechnologies offer backward compatibilitywith the 2G cdmaOne standard and operatein the same frequency bands, which eases thetransition to 3G.

While GSM/UMTS still dominates west-ern Europe, some operators are turning to 1XEV-DO to make use of spectrum in the

450 MHz band. This was previously used forfirst-generation analogue networks.

Meanwhile, in the US, the nation’s largestGSM operator is planning to proceed toW-CDMA. However, Cingular will need touse its existing spectrum at 850 and1900 MHz, because the US government isnot expected to license new spectrum for 3Gthis year. The government will begin licens-ing 3G spectrum for “advanced wireless ser-vices” in July 2006 at the earliest. A furthercomplication is that the 3G spectrum in theUS will not be the same as that used in therest of the world. This is a challenge forchipset and handset manufacturers, whomust add yet another band to their handsetsto support international roaming.

While clear progress towards 3G has beenmade in North America, the situation inChina – which is the world’s largest cellularmarket – remains unresolved. At present, thetwo primary operators in China, ChinaMobile and China Unicom, both use GSM,

3 G S T A N D A R D S

Worldwide 3Gstandards battle isin a crucial phase


1 6 O P I N I O N

M A R K P A X M A N


Will peer-to-peer networks provide greater bandwidth,or will they put operators in another fine mesh?

The ubiquity of e-mail and the Internet proves that mesh networks providea remarkably powerful, scalable, and low-cost transmission medium.Indeed, the success of the Internet has created a need for new meshtechnologies like BitTorrent.

Most nodes on the Internet are bandwidth-limited. Unless a user canafford a Google-sized server farm and a fibre-optic connection to theInternet, it is difficult to transfer large quantities of information. BitTorrentspreads the load, with every user hosting part of the content.

Wireless networks suffer from similar bandwidth restrictions. Airinterfaces are not getting much better in terms of range, spectral efficiencyor data transmission rates, and the challenges associated with providinghigh-speed data services within reasonably large cells will be around formany years to come. This suggests that it may be time to accept that the

“last-mile” delivery medium – the Internet orwireless – is improving only slowly, while thedemands for content grow much faster.

Mesh networks discard the concept of cellswith base stations at their centre. Instead, eachmobile device becomes both client and server. Itcaptures data relevant to itself and forwardsdata intended for other users. Both the capacityand data rate of a mesh network increase withthe density of users. However, users must

ensure that their devices are always switched on, and of course the usersmust be present in the first place. As a result, an overlay of traditional cellsites might be required to ensure service continuity.

Perhaps the greatest challenge facing mesh networks is human rather thantechnical. Success is contingent on the consensual behaviour of subscribers,who must accept that their handset battery will be drained as it forwardsdata to other users. BitTorrent solves this problem through a give-and-takeapproach, whereby a user can only receive content from BitTorrent if theyagree to participate as a host.

There are also the usual technical problems, including how to overcometransmission delays inherent in multi-hop networks; and how to coordinatethe mesh in the presence of highly mobile users.

Today, peer-to-peer networks like BitTorrent show that mesh networkingcan work from both an engineering and a social point of view. Adapting theengineering to wireless will be a lot of fun, but perhaps the first stage is toeducate the public about this new way of working. ■

Mark Paxman is a managing consultant at PA Consulting’s Wireless TechnologyGroup. He can be contacted at [email protected].

The greatestchallenge facingmesh networks ishuman ratherthan technical

with China Unicom also operating someCDMA networks. In addition, the two wire-line operators, China Telecom and ChinaNetcom, operate a quasicellular service calledLittle Smart, which is based on the JapanesePHS standard. This system does not providethe roaming and vehicular-speed mobility ofa true cellular system. Low-cost, low-powerhandsets are used, and the cost of a call is 10–20% of that of a cellular connection. Whilenot technically or legally a cellular system,Little Smart has given these wire-line opera-tors a taste of the wireless opportunity, andthey are expected to seek 3G licences.

While it looks certain that four operatorswill vie for 3G licences, the Chinese govern-ment has been silent on the timing anddetails of how licences will be issued, andwhich standards will be covered. Mostobservers now anticipate that the licences willbe issued some time in 2005.

The Chinese situation is further compli-cated by a home-grown Chinese 3G standardthat is recognized by international standardsbodies. Known variously as time-divisionsynchronous CDMA (TD-SCDMA), UMTS-narrowband time-division duplex (NTDD)or low chip rate (LCR), the technology usesnarrower channels than W-CDMA. UnlikeW-CDMA and cdma2000, TD-SCDMAuses the same frequency band for the uplinkand downlink, which makes more efficientuse of radio spectrum. In China, 160 MHz ofspectrum is reserved for unpaired operation,which suggests that the government plans toissue licences restricted to TD-SCDMA tech-nology. Many 3G licences awarded world-wide include both paired spectrum bandssuitable for W-CDMA and unpaired bandssuitable for TD-SCDMA operation.

The success of any new cellular standardis largely dependent on the availability ofhandsets that consumers will accept. Theymust be small, lightweight, last a long timeon a battery charge, and the cost must becommensurate with the value provided interms of features and convenience. Thismeans that handset chipsets must be avail-able to support the handset features and cost.While W-CDMA and cdma2000 have had ahead start in development and are now intheir second or third-generation implemen-tations, chipsets for TD-SCDMA are nowemerging from the development labs, andconsumer-grade handsets are being used infield trials. This will level the playing field asthe battle for the airwaves in China beginsin earnest. ■

Doug Grant is director of businessdevelopment for wireless products at US-basedAnalog Devices.



Xinger-II® E-SizeAMPS-band3dB90°couplersAvailable in our popular, new Xinger-II format, Anaren’s XC0900E-03 features:> Low profile at only

.2 x .56 x .092” (5.08 x 14.22 x 2.34mm)

> 800-1000MHz> Very low loss: 0.20dB max> High power: 120 CW Watts> Tight amplitude balance:

+/- 0.20dB max> High isolation: 21dB min> Tape & reel> Lead-free or tin-lead> Well-suited for balanced power,

low-noise amps, and more!Call for free samples or test-board (for qualified inquiries).

Xinger-II® PicoAMPS-band10 & 20dB directional couplersYou asked for 800MHz pico couplers?Anaren listened, with our all-newXC0900P-10 and XC0900-20 parts:> Compact format, only

.2 x .25 x .08”(5.08 x 6.35 x 2.03mm)

> 800-1000 MHz – including 869-894 MHz and 925-960 MHz bands

> Low loss: 0.65dB max> 1.4:1 max VSWR> Excellent frequency sensitivity:

+/- 0.3dB max> Directivity: 15dB min> Tape & reel> Lead-free> Excellent choice for power

and frequency detecting, and VSWR monitoring!

Call for free samples or test-board (for qualified inquiries).

Xinger-II® Pico1400Mhz3dB90°couplersAnaren’s brand new Xinger-II,the XC1400P-03 offers:> Small footprint measuring

a mere .2 x .25 x .110”(5.08 x 6.35 x 2.78mm)

> 1200-1600MHz – including 1215-1240 MHz and 1563-1588 MHz bands

> Low loss: 0.35dB max> Power handling: 45 CW Watts> 1.2:1 max VSWR> Isolation: 20dB min> Amplitude balance: +/- 0.3dB max> Tape & reel> Lead-free> Excellent choice for GPS quadrature

antenna feed networks. Call for free samples or test-board (for qualified inquiries).

Xinger-II®

“B-size”3dB90°couplersNewly rendered in Anaren’s Xinger-IIformat, our new “B-size” couplersfor 900, 1900, 2100MHz offer you:> Space savings, at only

1.0 x 0.5 x 0.135”(25.4 x 12.7x 3.43mm)

> Low loss: 0.09dB max> High power> 1.06:1 max VSWR> High isolation: 25dB min> Tape & reel> Lead-free > Well suited for high-power

amplifiers, balanced amplifiers and signal distribution platforms.

Call for free samples ortest-board (for qualified inquiries).

In Europe, call 44-2392-232392 > ISO 9001 certified Visa/MasterCard accepted (except in Europe)

800-411-6596 > www.anaren.com

These are for what’s next.

That was then.

This is now.

http://www.anaren.com

REGISTER NOW www.ibctelecoms.com/ims

+44 (0) 20 7017 5506 [email protected]

Featuring key presentations from leading experts including:

Invaluable Case Studies and Insights:• Reducing the cost of IMS

deployment

• IMS Service Testing

• IMS Migration andInteroperability

• SIP Services

• Services for IMS

• Assessing AlternativeStrategies for the IMS client

• IMS and Fixed MobileConvergence

• IMS Standardization

Conference and Exhibition | Renaissance Brussels Hotel | 12 & 13 April 2005

THE FIRST AND ONLY EVENT FOCUSSED EXCLUSIVELY ON IMS

Lead Sponsor:

Sponsors:

Delegate

fee £1199

3 delegates attend

for the price of 2

Lowry Stanage, President ofNetworks, BT Global Services Dr Subrata De, Head of CoreNetwork Evolution & Strategy, Vodafone GlobalAndrew Motley, Head ofTechnology Futures, 02Ed Candy, CTO, 3Dr Alexander Kuchar,Director Mobile ServiceNetwork, Mobilkom AustriaAntonella Napolitano,Manager, Standardization,TIMLuis Angel Galindo, NetworkTechnology Expert, Telefonica

Toon Norp, BusinessConsultant, TNO Informationand CommunicationTechnology (previously KPNResearch)Vincent Talaouit, Technology& Innovation, MultimediaServices Program Manager,OrangeDavid Boswarthick, TechnicalOfficer, Fixed CompetenceCentre, ETSIJean-Pierre Bonaime,Chairman, UMTS ForumAlex Sinclair, Chief Engineer,GSM Association

Television and mobile radio are converging – empowered by Rohde & Schwarz. We've beenat the forefront of both technologies for years. Whether you're looking for DVB-H-capabletransmitters, data inserters, test generators or analyzers, all devices are already here andready to put you in front of the field.So it's easy to stay on the fast lane of mobile radio technology. Just make a pit stop at ourbooth at the 3GSM World Congress – it'll be worth your while.

DVB-H – two technologies, one market leader

www.rohde-schwarz.com

Feb 14 –17, Cannes

Hall 2, Booth F44

Reference equipment for both sides of the medal

http://www.ibctelecoms.com/ims

http://www.iir-conferences.com/performance

http://www.rohde-schwarz.com

Cellular networks are becom-ing increasingly complex, witheach new service or serviceconcept pushing at the limitsof technology. The evolutionfrom simple voicemail throughto text and multimedia messag-ing, WAP gateways, locationcentres, push-to-talk serversand so on represents an incre-mental but relentless expansionin the diversity of protocolsand interfaces required toimplement wireless services.

The challenge for the net-work operator is how toexploit the capability andcapacity of the network serviceenvironment in an economicmanner. The answer lies with a“carrier-network operating sys-tem”. Based on open standards, this architectural approach maybe more costly than isolated solutions, but it will ultimately bemore flexible and provide natural scalability.

Historically, new services have been introduced as single-function systems – often described as vertical silos. There hasbeen no cross-functional capability, and the service silos them-selves have limited connectivity to external resources or data.The most obvious examples of this vertical integration are theintelligent network services, where the service creation, controland switching elements are usually sourced from a single net-work-equipment provider. This has resulted in little competi-tion or innovation in the market for traditional voice services.

This shortcoming was highlighted by analyst firm The YankeeGroup at the 2004 European Wireless Leadership Summit inLondon, which identified “service enablement” as one of the keyinitiatives for mobile network operators. Silo services deployedtoday reflect market immaturity, and make it difficult for oper-ators to exploit existing investments. Fortunately for newer ser-vices, such as those based on messaging and location, there is amove away from this tightly coupled relationship, and the basisfor a service architecture is starting to emerge.

This architecture is based onopenly defined interfaces andprotocols, which enable theseparation of service logic fromthe service platform. As aresult, systems integrators andindependent vendors will beable to compete alongside coreequipment vendors. In addi-tion, architectures based oninformation technology (IT)and computer platforms willbecome commonplace.

A full carrier-network oper-ating system encompasses andenhances individual verticalsystems to provide a harmo-nized and managed interface tothe telecoms network. In manyways this reflects the benefitsthat the UNIX and DOS oper-

ating systems conferred on an emerging computer industry sev-eral decades ago. It provides an abstracted interface to thecapabilities of the telecoms network, and removes the need forspecialist knowledge of network protocols and triggers.

Defining functionsAn operating system provides a set of software functions toaccess capabilities within the network. Defining these functionshas been the task of the Third Generation Partnership Project(3GPP)/ETSI and Parlay Group standards bodies. These orga-nizations have defined the Open Service Access (OSA) applica-tion programming interface, which provides a set of functionsfor the individual service capabilities within a network. Thesefunctions range from call control through charging to presenceand a range of other capabilities. They are supported by tech-nology mappings including Standard Java and Enterprise Javaenvironments. This allows OSA to be embedded within stan-dard software tools, enabling developers to create applicationsthat include business logic that is supported through the mobilenetwork. This is a subtle and significant change to creatingapplications that are simply delivered across the network.

1 9D A T A S E R V I C E S


Network operating systemwill unite telecoms and ITOperators, equipment providers and the IT industry are joining forces to develop a carrier-network

operating system to ease the deployment of wireless data services. Kieran Dalton explains.

A carrier-network operating system will speed the development of wirelessservices for business users.

▲▲

NOKI

A


Agilent’s next-generation measurement platforms will help youovercome the toughest challenges in microwave and millimeter-wave design - new technologies, narrow margins and complextest requirements. With new levels of performance, flexibilityand connectivity, Agilent equipment assures you out-standing performance to keep your design on schedule.

PSA Series high-performance spectrum analyzers extract noisefigure, phase noise, and more from complex signals to 50 GHz,extendable to 325 GHz.

PSG signal generators create complex waveforms to 44 GHz andanalog waveforms to 67 GHz (extendable to 110 GHz), with highoutput power and low phase noise.

PNA Series microwave network analyzers characterize linearand frequency-translating devices from 10 MHz to 110 GHz,extendable to 325 GHz.

What’s more, combining these instruments with our AdvancedDesign System (ADS) environment creates a connected solutionthat can help you achieve even fewer and faster design iterations.

For more information, including application notes, product infor-mation and to order our test and measurement catalog CD, go towww.agilent.com/find/mwtools. And see how Agilent tools willhelp you with any challenge you encounter.

PSA Series high-performance spectrum analyzers with one-button measurements

PSG signal generators with integrated vector modulation and PC-based signal generation tools

PNA Series microwave network analyzers, with electroniccalibration and vector-corrected mixer techniques

Every adventure has its essentialsEngineering is no different

• Austria 0820 87 44 11 • Belgium +32(0)2-4049340 • Denmark +45 70131515 • Finland +358(0)108552100 • France 0-825 010 700*• Germany 01805 24 6333**• Ireland 1890-924 204 • Israel +972 3 9288 504

www.agilent.com/find/mwtoolsd• Italy +39 02 9260 8484 • Netherlands +31(0)20 547 2111 • Spain +34 91 631 3300 • Sweden 0200-882255 • Switzerland 0800 80 53 53 • UK (0)7004 666666

• International +41-22-780-6111

*Numéro indigo = 0,125 Euros HT la minute **0,12 Euro/min©Agilent Technologies, Inc. 2004

http://www.agilent.com/find/mwtools

2 1D A T A S E R V I C E S


The first step is to define the carrier-network operating system and provide therelevant information to third-party servicedevelopers and providers. Initially, this willenable systems integrators to extend existingservices used by businesses to incorporate net-work capabilities and to create market oppor-tunities for a new generation of serviceproviders and independent software vendors.However, in the longer term, network func-tionality must be embedded in any new IT,media or telecoms domain. To achieve this,it is important that parallel developmentsoccur in the IT industry.

Traditional IT solutions have grown inex-orably in terms of cost and complexity overthe last decade. However, as developmenttimes and maintenance costs have spiralled,the focus has shifted towards establishing a new service archi-tecture that would promote re-use and modularity. As a result,Web services are underpinned by a service-oriented architecture,which is a collection of services that can communicate with eachother. Each service provides a well defined self-contained func-tion. Complex services can be realized by coordinating – ororchestrating – two or more component services.

This concept from the IT domain is also shared by OSA/Parlay, which is a set of standardized, open interfaces for usingnetwork capabilities. OSA/Parlay allows client applications tocreate end-user services through combining individual servicecapabilities. Where OSA/Parlay and Web services differ is inthe level of coupling between the client application and theenabling service. OSA/Parlay assumes a tight coupling, using astandard defined interface specification endorsed by 3GPP. Anyclient application that conforms to this specification may accessOSA/Parlay functionality offered by an operator.

Web services, however, assume loose coupling, where theinterface is described publicly in a central directory. Clientapplications may retrieve this description and use it to create aconnection to the service. Loose coupling allows applicationsto discover and employ services without prior knowledge of theservice, thanks to a more descriptive communication protocol.Consequently, tightly coupled applications are more efficient.However, the market requirement, driven by the available toolsand software practices, is for loosely coupled solutions.

To extend telecoms functionality into the business domain,and to incorporate telecoms capabilities into a broad range ofservices, a carrier-network operating system must be compatiblewith the loosely coupled world of Web services. This is whereParlay X comes in, as illustrated in the figure.

Parlay X provides a higher-level abstraction of the base servicecapabilities defined by OSA/Parlay. Each of the Parlay X servicesoffers an individual function that may be wrapped as a distinctservice and incorporated within a Web-services architecture. Asit conforms to the publicly defined standards endorsed by 3GPP,Parlay X can be thought of as a tightly coupled service that isdelivered using loosely coupled techniques. Thus it is compatiblewith the programming methodologies and tools of the businessworld, yet retains the control, service agreements and commer-

cial contracts of the telecoms domain.The simplicity offered by Parlay X, in terms

of both service development and controlthrough OSA/Parlay, has encouraged earlyadvocates such as the US-based operatorSprint to endorse Parlay X as a key tool fordelivering innovation from the edge of thenetwork. The Sprint Business Mobility pro-gramme encourages service providers to inte-grate with the Sprint network to deliver newinnovative services to their corporate andconsumer customers. Early advocates of thismodel include IT giants such as Microsoftand IBM, who will encourage operators toexploit mature products from vendors such asEricsson, Alcatel and UK-based AePONA.

In summary, a carrier-network operatingsystem will provide the basis for service

enablement within telecoms networks. This will create the envi-ronment for supplier competition, component re-use and a levelof service innovation that has been lacking to date. Parlay andParlay X, with their inherent service-oriented architecture, pro-vide the basis for this network operating system, particularlywith their support for next-generation networks and servicemigration through abstraction.

Future challengesHowever, there are still issues to be resolved. A true networkoperating system, particularly one used for a distributedmachine such as a telecoms network, requires interrupt sup-port and processor control. For a telecoms network, this equatesto the ability to manage multiple asynchronous service invoca-tions and the feature interaction between these disparate ser-vices. While vendors like AePONA provide ready-to-useOSA/Parlay and Parlay X solutions to achieve this, it is impor-tant in the long term that they are aligned with the emergingstandards for multiple points of service control. This will main-tain the modularity and interoperability promoted by Parlay.AePONA and other vendors in the Parlay community havemade clear their commitment to maintaining the currency oftheir standards-based solutions over time.

Similarly, any operating system requires a defined-file struc-ture and data format. While initial attempts within both Parlayand the Open Mobile Alliance at defining a generic user profilehave stalled, it is important that data access, if not the data for-mat and storage, becomes standardized. Again, early innovatorswill offer solutions for data correlation and aggregation; how-ever, any long-term solution will require standardization.

Despite the many challenges, the basis of a carrier-networkoperating system has been defined, and companies such asAePONA are offering standards-based solutions. The fusion ofdisparate service elements into a service enablement layer hasbeen achieved, and benefits are emerging in terms of innovationand revenues. In embarking on this, it is important to recog-nize that the network itself is an enabler – it is the services thenetwork provides that contain value and opportunity. ■

Kieran Dalton is chief technical officer at UK-based AePONA.

services

network resources

Parlay X

Parlay

carrier-networkoperating system

Parlay and Parlay X form the core of thecarrier-network operating system.


The offspring of genius and innovation.

The POLARIS™ 2 TOTAL RADIO™

solution is the industry’s firsttransceiver with direct digital polar modulation in production.Containing digital and analogbaseband interfaces, it offers morebaseband choices while providingthe best receive sensitivityacross all four bands,reducing the potentialfor dropped calls.

It’s a newgeneration

of performance.Brought to you by RF Micro Devices®.

• Patent pending polar modulator for superior performance and extended battery life

• Optimized to work with a saturated power amplifier

• Quad-band operation: 850, 900, 1800, 1900 MHz

• Supports GSM, GPRS and EDGE air interface standards and is Class 12 capable

• Digital and analog baseband interfaces

• Superior receive sensitivity of - 109bBm

We are Wireless.

Cellular

Wireless LAN

Bluetooth®

Infrastructure

GPS

wireless technology

ISO 9001: 2000 Certified / ISO 14001 CertifiedRF MICRO DEVICES®, RFMD®, Enabling Wireless ConnectivityTM, POLARIS™, POLARIS 2™ and TOTAL RADIO™ are trademarks of RFMD, LLC. BLUETOOTH is a trademark owned by Bluetooth SIG, Inc., U.S.A. and licensed for use byRF Micro Devices, Inc. ©2005 RFMD.

For sales or technical support, contact [email protected]. www.rfmd.com

UK Sales OfficesLee Fitzgerald/Southern Sales Office

+44 (0) 1252 691687E-mail: [email protected]

Paul Stoneley/Northern Sales Office+44 (0) 1743 761822E-mail: [email protected]

USA/Corporate Headquarters: RF Micro Devices, Inc.Tony Testa

Phone: 336.664.1233 Fax: 336.931.7454 E-mail: [email protected]

RF Micro Devices, SwedenMorgan Widung

Phone: +46.46.152080Fax: +1.336.678.0068E-mail: [email protected]

RF Micro Devices, FinlandTommi Hiillos

Phone/Fax: +358.9.855.0105E-mail: [email protected]

http://www.rfmd.com

2 3D O W N L I N K


The high-speed downlinkpacket access (HSDPA)enhancement to W-CDMA provides a smoothevolutionary path to higherdata rates for UMTS net-works. HSDPA delivershigher capacity throughimproved spectral effi-ciency, which provideshigher data rates, shorterresponse times and betterquality of service. It alsosupports the sharing ofchannels between users,ensuring that channelresources are utilized effi-ciently for packet data.

As part of Release 5 (R5)of the UMTS standard,HSDPA introduces a new downlink (DL) transport channelthat supports asymmetric and bursty packet-data services. Thisincreases practical peak data rates to about 10 Mbit/s andimproves the DL shared channel (DSCH) throughput com-pared with current Release 99 (R99) channels.

This is supported through the introduction of fast and com-plex channel-control mechanisms based on a short fixed-packettransmission time interval (TTI), adaptive modulation and cod-ing (AMC) and fast layer-1 hybrid automatic repeat request(L1 H-ARQ). To facilitate this fast scheduling with a per-TTIresolution that corresponds to the instantaneous air interfaceload, the HSDPA-related medium-access control (MAC) func-tionality has been relocated to the base station.

R5 HSDPA introduces a shared MAC-high speed (MAC-hs)layer and a special high-speed DSCH with the necessary controlchannels. This is similar to the R99 DSCH, but without fastpower control. Transmission time is allocated to the handset ona TTI (sub-frame) basis. Modulation, effective code rate, powerand other transmission parameters can be adjusted dynamicallyby the TTI-based AMC.

New technologies in R5 HSDPA include higher-order modu-lation schemes and low redundancy coding combined with

incremental redundancy.Further enhancements toreduce requirements onlink performance includeL1-based fast H-ARQ andtransmit/receive (Tx/Rx)antenna diversity. Parallelchannels are facilitated bymulticode in R5. In R6,HSDPA will introduceantenna array processingtechnologies to enhancethe peak data rate to about30 Mbit/s. This willinvolve smart antennasusing beam forming forhandsets with one antenna,and multiple-input multi-ple-output (MIMO) forhandsets, PDAs and laptop

computers with up to four antennas.In HSDPA, the base station determines the channel quality of

each HSDPA-active handset based on power control, QoS,acknowledge/non-acknowledge (ACK/NACK) ratio and hand-set-specific quality feedback. Fast scheduling and link adapta-tion are then performed promptly depending on the activescheduling algorithm and the user prioritization schemeemployed by the base station.

A number of additional channels and a layer are introduced inorder to implement HSDPA features. The high-speed sharedcontrol channel (HS-SCCH) is the DL signalling channel thatcarries key physical layer control information. This informa-tion enables the demodulation of the data on HS-DSCH andsupports the data sent on HS-DSCH in the case of retransmis-sion or an erroneous packet. The information includes chan-nelization code set, modulation scheme, transport block size,H-ARQ process information, redundancy and constellation ver-sion, and new data indicator.

The high-speed dedicated physical control channel (HS-DPCCH) is the uplink (UL) signalling channel that carries thenecessary control data in the UL. These are ARQ acknowledg-ments and DL quality feedback information to be used in the

New control channelsboost HSDPA performance

HSDPA employs variable modulation and coding schemes to adapt to changes in downlink signalquality. Faris Muhammad explains the myriad of new control channels that make this possible.


2 4 D O W N L I N K


base-station scheduler. It carries an ACK/NACK indication, toreflect the results of the cycling redundancy checking after thepacket decoding and combining. It also carries the DL channelquality indicator (CQI) to indicate which estimated transportblock size, modulation type and number of parallel codes couldbe received correctly with reasonable block error rate in the DL.

The high-speed physical downlink shared channel (HS-PDSCH) is the physical channel that carries the user-specificpacket data in the DL from the transport channel HS-DSCH. Ithas a fixed spreading factor of 16 and multicode transmissionusing up to 15 codes. The peak data rate is 10 Mbit/s range with16 quadrature amplitude modulation (16QAM). The HS-DSCH interleaving period TTI is reduced to 2 ms to achieveshorter round-trip time between the handset and base stationfor retransmissions.

With the introduction of HS-DSCH, additional intelligencein the form of a new MAC-hs layer is required so that the basestation can control retransmission directly. This expeditesretransmission and reduces delay with packet data operation.The prime function of the new MAC-hs is to manage H-ARQfunctionality, scheduling and priority handling.

The fast power control and variable spreading factor of R99DSCH is replaced in the R5 HS-DSCH by variable modulationand coding schemes. These cover a wide dynamic range in orderto cope with the varying DL radio and channel quality condi-tions at the handset. HSDPA adapts to these conditions by

modifying the effective code rate, the modulation scheme, thenumber of codes used and power per code.

The scheme used by HS-DSCH is based on R99 rate 1/3turbo encoder, but adds rate-matching in order to obtain a finerresolution of the effective code rate. To achieve very high peakdata rates, 16QAM is used in addition to the R99 quadraturephase shift keying scheme. 16QAM modulation and fast linkadaptation can be combined to optimize the instantaneous useof the varying radio channel. The variation in the channel canbe tracked almost instantaneously because the TTI is only 2 ms(compared with 10 or 20 ms in R99), and scheduling and linkadaptation are determined for each TTI. 16QAM makes betteruse of the available bandwidth, but demands more receivepower per bit. Therefore 16QAM is more suited for bandwidth-restricted applications (nearer to the base station) than forpower-restricted applications.

Fast packet scheduling functions are performed by the MAC-hs in the base station. These functions manage the HS-DSCHresources, select the coding/modulation scheme and the Txpower for the HS-DSCH data packets. The handsets thatshould be scheduled within a particular TTI are determinedusing CQI reports coming from the handsets. Channel condi-tion-dependent scheduling rather than sequential schedulingcan increase the capacity significantly and make better use ofair interface resources. Fast scheduling also allows guaranteedbit-rate services using packet scheduling without the need for a

Strategically Deploying

HSDPAConference 25-28 April 2005, Lisbon

IIR are delighted to announce the first ever HSDPA event. IIR's StrategicallyDeploying will provide a clear understanding of the business case for mobileoperators to invest in HSDPA, the migration challenges, costs and benefitsand the services it will enable.

The conference takes place 26-27 April 2005, Sana Malhoa Hotel, Lisbon. The week begins with a pre-conference introduction to HSDPA workshop on 25th April and the main conference will be on 26-27 April. The event then concludes on 28th with a post-conference technical briefing.

Hot Topics to be discussed include:■ Determining When, Where And How To Deploy HSDPA■ Identifying And Overcoming The Strategic And Technical Challenges Of

Migrating From 3G to 3.5G (HSDPA)■ Assessing How Mobile Operators Can Efficiently Implement HSDPA Whilst

Optimising Earlier Technology Investments■ Comparing HSDPA With Alternative Wireless Broadband Access

Technologies ■ Highlighting The Services That HSDPA Will Enhance And Enable And

Assessing How To Maximise ROI And ARPU■ Planning For Future 3G Network Capacity Requirements: Assessing The

Costs And Benefits Of HSDPA■ Examining The Predicted Data Rates For HSDPA And Determining To What

Extent They Can Be Achieved In Live Networks■ Examining The Technical Specifications Of HSDPA PC Cards And Handset

Development And Determining When These Will Be Commercially Available

www.iir-conferences.com/hsdpa


http://www.iir-conferences.com/hsdpa

http://www.microcrystal.com

2 5D O W N L I N K

dedicated channel. Handsets are prioritized by the scheduleraccording to the channel conditions, the amount of data pend-ing in the buffer for each user, the elapsed time for that usersince last served, and pending retransmissions for a handset.

The H-ARQ scheme enables the handset to quickly requestretransmission to compensate for errors resulting from the linkadaptation process. H-ARQ also offers improved error-rate per-formance compared with conventional ARQ.

The handset tries to decode each received transport blockand pass the result to the base station. The H-ARQ processallows the base station to quickly respond to a handset request toretransmit. The handset then combines information from theprevious transmission with the new retransmission, aiming forsuccess in a second attempt.

The base station can choose from two H-ARQ methods,depending on the amount of soft memory available at the hand-set. The first is the soft (chase) combining method, in which thesame packets are resent to the handset. This method requires lesshandset buffer memory, and is the only method used at thehighest data rate. The second method is called incrementalredundancy, and involves retransmissions that are not identi-cal. It offers slightly better performance, but uses more handsetmemory because the retransmissions require more processing.This approach is more suited to lower data rates.

HSDPA-enabled handsets will be able to perform H-ARQoperation, multicode processing, HS-SCCH reception, fast data

rate processing and HS-DPCCH signalling. The Third Genera-tion Partnership Project (3GPP) has defined a number of hand-set categories. These allow for different levels of handsetcomplexity that are based on a maximum number of supportedHS-DSCH codes, minimum inter-TTI interval, L1 peak datarate, ARQ type and modulation scheme. New functionalities,capabilities and features require testing, and therefore a newgeneration of R5-capable test equipment is a necessity.

Aeroflex has addressed the development needs of HSDPAhandset makers in its 6401 handset test platform. The 6401can emulate a number of HSDPA cells on different carriers witharbitrary numbers of physical channels on each cell. A built-inscalable multichannel fading simulator, additive white Gaussiannoise sources and DL channel diversity are supported. Thisenables the test of HSDPA-capable handsets during both thedevelopment and 3GPP HSDPA conformance phases.

For most applications, traffic in the DL is far greater thanthe UL. However, for peer-to-peer applications such as videoconferencing, data flows equally in both links. To enable high-quality video to be passed, it is therefore essential to ensure thatthe UL performs as fast as the DL. Work has begun already ondeveloping the standards for high-speed uplink packet access(HSUPA), and many of the techniques used in HSDPA will alsobe used for HSUPA. ■

Faris Muhammad is technical consultant at US-based Aeroflex.


KATHREIN-Werke KG ·Telephone +49 8031 1 84-0 ·Fax +49 8031 1 84-8 20Anton-Kathrein-Straße 1-3 · PO Box 10 04 44 · D-83004 Rosenheim · Germany Antennen · ElectronicInternet: http://www.kathrein.de

Kathrein leads the world in antennatechnology, offering a broad range of products for use in mobile communication systems rangingfrom 25 MHz to 2.5 GHz.

Kathrein professional productsinclude antennas, filters, combi-ners, amplifiers and accessories.

More than 240 major network operators around the world rely onKathrein’s superior quality, state-of-the-art technology and over 85 yearsof experience.

Kathrein offers you the very bestsolutions for all your antenna systemrequirements!

Visit us at the 3GSM WorldCongress 14.02. - 17.02.2005 inCannes (Stand hall 2 G4).


http://www.kathrein.de

Smooth wall construction is the smartalternative to corrugated cable

> Superior Performance & Reliability

> Exceptional Customer Service

> Easy Installation

> Greater Return on Your Investment

[email protected]

©2005 Com

mScope, Properties, LLC. All Rights Reserved •

1/05 • CR-0054-C

CommScope USA • Toll Free: 1.888.CELL.REACH (235.5732) • Tel. (US): 1.828.324.2200CommScope Europe S.P.R.L • Belgium • Tel + 32.64.52.19.11 CommScope Cabos do Brasil Ltda. • Brazil • Tel+55.19.3867.6800

Cell Reach® and ExtremeFlex™ smooth wall wirelesstransmission line cable and connectors prevent wateringress and provide lower life cycle costs over time.Contact us and we will e-mail you a case study on

why an operator specified CommScope smooth wallcable and how life cycle costs decreased—adding

profits to their bottom line.

Visit us at these events:

3GSM World Congress - FFebruary, (14-117)

Cannes, (Booth E13)

CTIA- MMarch, (14-116)

New Orleans (Booth 5368)

Learn how our lowest life cycle cost can save yousignificant money and improve performance.

Lower Life Cycle Cost

http://www.commscope.com

Radio designers are at the frontline of the battle to delivermore advanced handsets thatoffer seamless interoperabilitybetween 2G and 3G networks.The current drive to employthe EDGE enhancement toGSM has added a new level ofcomplexity to handset design,because devices must support anew modulation scheme called8-PSK, as well as the GMSKmodulation used by GSM.

However, the challenges donot end with the modulationscheme. EDGE is a GSM tech-nology and therefore employsthe time-division duplexing (TDD) approach, whereby anantenna-switch module alternates the radio between transmitand receive modes. This is fine for GSM-only handsets, butmakes it difficult to design the latest dual-mode GSM/UMTSdevices, which must support the 3G W-CDMA air interface.Instead of using TDD, W-CDMA employs frequency-divisionduplexing (FDD), whereby the transmitter and receiver worksimultaneously via a duplexer.

W-CDMA employs the QPSK modulation scheme, whichinvolves both amplitude and phase modulation. GSM/GPRS/EDGE channels are spaced at 200 kHz, whereas 5 MHz are usedin W-CDMA. Finally, the channel bit rates for GSM/GPRS/EDGE are based on a 13 or 26 MHz clock, whereas W-CDMAuses a chip rate based on a 19.2 MHz clock. And if this wasn’tcomplicated enough, in order to support worldwide roaming,handsets must function in at least five frequency bands – 850and 900 MHz, and 1.8, 1.9 and 2.1 GHz.

While this diversity of standards and specifications can seemoverwhelming, there are two important factors working in thedesigner’s favour. First, both EDGE and W-CDMA use linearmodulation schemes, so some of the challenges for designers ofmultimode handsets can be addressed in a common approach.Second, chip manufacturers are using silicon integration toaddress some of the complexity-related issues and create credibletechnology for the radio portion of advanced handsets.

Integrating EDGE and/or W-CDMA functionality in a

GSM/GPRS handset requires a radical rethinking of the entireradio architecture. On the receiver side, amplitude modulation(AM) suppression must be achieved in the presence of GSM/GPRS blockers that are of constant amplitude, while EDGEand W-CDMA blockers are amplitude-modulated.

In order to broadcast EDGE and CDMA signals, the trans-mitter must be highly accurate to guarantee high linearity fromthe baseband to the antenna. The transmitter must also pro-vide high power-added efficiency. A key feature of FDD is thesimultaneous operation of the transmit and receive blocks,which means that the blocks must work well together. In par-ticular, the designer must ensure that the receiver can suppressblockers produced by the transmitter.

Detecting offsetsGSM/GPRS handsets often use direct-conversion receivers,which have a low component count and hence a low cost.However, direct conversion can suffer from DC offsets in thebaseband. This problem arises from a variety of sources includ-ing inherent circuit offsets, self-mixing of the local oscillator, ref-erence clock harmonics, or blockers received at the antenna.Some DC offsets can be detected and suppressed by a calibra-tion procedure. However, AM blockers such as those introducedby EDGE and W-CDMA are extremely difficult to detect, andusually cannot be removed by filtering without some loss inthe desired signal.

2 7H A N D S E T S


Complexity increases as EDGEbridges the generation gapWhile EDGE radios contain elements of both GSM and UMTS technology, Patrick Morgan

explains that GSM/EDGE/W-CDMA integration can benefit from a radical rethink.

The Aero II transceiver from Silicon Laboratories employs low-IF technology to improve sensitivity.

▲▲


The new 6.2" TFT from Three-Five Systems has been introduced to satisfy the demand for increased information content and high brightness. As part of the already successful TFS range of TFT products the 6.2" model benefits from 262K colours, timing controllers, rugged construction and integrated touchscreen. As with all TFS products there are several integration options available including custom modifications.

• 640 x 240 pixels

• 262K colours for vivid reproduction

• Transmissive, high brightness, high contrast

• 4 or 5 wire touchscreens available

• Touchscreen and timing controller options

• LVDS options

• Viewing angle 6 o’clock or 12 o’clock01635 33209www.intelligentdisplay.com

NOW AVAILABLE THROUGH

[email protected]

The bigger picture from Three-Five Systems

The TFS3224-012 TFT-LCD display module productfrom TFS has been designed to address the currentand future needs of high tier handheld gaming,organizer and telecoms products. The advancedQVGA (320 x 240 pixel) format in a 2.83"diagonal display has been developedusing advanced transflectivetechnology to provide better imagequality in all lighting conditions. Highcontrast, high response speed and wideviewing angles make the display thecentrepiece for a compelling handset product.Available as standard or as semi-custom variantsin an integrated design that reduces overallinterconnect and thickness for lower total systemcosts.

• 2.83" diagonal display

• 320 x 240 pixels

• Internal transflective technology

• High contrast, high response speed

• Standard and semi-custom variants

• Wide viewing angles

A better gaming experiencefrom Three-Five Systems

Contact TFS at:

Tel: +44 (0)1793 549100Fax: +44 (0)1793 549135Email: [email protected]

www.tfsc.com

http://www.intelligentdisplay.com

http://www.tfsc.com

2 9H A N D S E T S


A more robust approach tothe suppression problem is toprevent DC offsets from reach-ing the baseband processor.This is done by replacing thedirect-conversion receiver witha low-intermediate frequency(low-IF) receiver architectureas illustrated in the figure(right). Unwanted DC offsetsare mixed away to the interme-diate frequency, which allowsthem to be filtered out. Thisimproves the receive sensitivity because it precludes the needfor the baseband DC offset correction algorithms used by direct-conversion receivers. Measurements on production handsetsshow that low-IF techniques can improve sensitivity by0.5 dB or more, with negligible impact on blocking perfor-mance. Silicon Laboratories’ Aero II transceiver uses this low-IF receiver architecture.

The offset phase-locked loop (OPLL) is the most commontransmitter architecture in GSM/GPRS handsets. This tech-nique meets the demanding modulation-spectrum requirementsfor GMSK by doing an excellent job of filtering in-band noise.Out-of-band noise is typically suppressed by the additional fil-tering of the transmitter voltage-controlled oscillator (VCO)phase noise to meet the receive band noise requirement.However, the OPLL only supports phase modulation, whileEDGE and W-CDMA require amplitude modulation to imple-ment 8-PSK and QPSK respectively. Therefore with both thetransmitter and the receiver, designers must consider the entireradio architecture when creating multimode handsets.

Different approachesOne way forward is to deploy a polar-loop transmitter, in whichthe signal is applied to the power amplifier (PA) through sepa-rate amplitude and phase feedback pathways. A variant of polarloop called polar modulation operates without feedback, whicheliminates the need for a coupler.

Both schemes require precise matching of the amplitude andphase delays through the feedback loops. Simulations indicatethat the modulation spectrum will not meet the required speci-fications at the 400 kHz offset if the delay mismatch is approxi-mately 30 ns or greater. However, a maximum 30 ns timeconstant constrains the filter bandwidth on the transmitterVCO to be at least 5 MHz, which limits suppression of the out-of-band VCO phase noise.

An alternative approach involves the addition of a companionchip and is architecturally simpler than polar modulation. Thecompanion chip is added to an existing GSM/GPRS transceiverand comprises a direct up-conversion mixer and a variable gainamplifier. In GSM/GPRS mode, the companion chip isbypassed. However, during EDGE or W-CDMA operation,the OPLL is unmodulated and held in continuous-wave mode.This acts as a local oscillator, which up-converts the basebandI/Q signal. This architecture preserves the excellent GSM/GPRSperformance of the OPLL, while also positioning the radio totake advantage of future trends in silicon integration. This is the

only architecture currently inproduction for both GSM/EDGE and CDMA/WCDMAhandsets. Unlike polar modu-lation, which requires a specialor customized PA, the lineartransmitter architecture iscompatible with PAs frommultiple vendors.

As multimode handsetsbecome more common, radiosbased on a digital low-IFreceiver and a linear transmit-

ter should deliver excellent performance. In addition, siliconvendors are likely to continue their integration efforts to reducethe total handset radio bill-of-materials (BOM) to a value simi-lar to that of GSM/GPRS.

Chip makers are pursuing two different approaches at theradio front end. One approach involves combining the switch/duplexer and receive-path SAW filters in a single package, andthe other is the integration of the PA and switch/duplexer. Atthe transceiver level, the complete integration of sensitive com-ponents – including loop filters, VCO tuning components, anda digitally-controlled crystal oscillator – improve performanceby shielding the local oscillators from external noise sources.This design also eliminates costly high-precision discrete com-ponents such as film capacitors from the radio BOM.

As transceiver integrationextends further into the future,CMOS manufacturing tech-nology could eliminate mixed-signal functions from thebaseband processor. A singlemixed-signal CMOS trans-ceiver would include thereceive-path analogue-to-digitalconverters and filters, the trans-mit-path digital-to-analogueconverters and filters, auto-matic frequency control, and

PA ramp digital-to-analogue converters and front-end controldrivers. Such a transceiver could interface directly to an all-digitalbaseband processor via a high-speed digital interface such asDigRF. This would allow the baseband processor to be more eas-ily scaled and manufactured by the latest process technology,reducing the overall cost and increasing the performance.

While it is true that RF designers face unprecedented chal-lenges in designing radios for multimode handsets, solutionsdo exist for most of these problems. New architectures anddevices will support the wide range of standards used for mobiledata. As silicon integration continues, it looks likely that CMOSmanufacturing technology will eventually bring multimode tothe same price point as standard GSM/GPRS handsets, andalong the way should provide an easily implemented solutionto ease the RF designer’s troubles. ■

Patrick Morgan is Wireless Product Marketing Manager atUS-based Silicon Laboratories.

850

900

1800

1900

++

PGA

PGA

+

+LOW-IF digital

PGAI

ADC

PGAQ

ADC

0 / 90

VCO + frequencysynthesizer

I

Q

RFIA

RFIE

RFID

RFIP

LNA

LNA

LNA

LNA base

band

anal

ogue

inte

rface

digi

tal f

ilter

DC offsets in a GSM/EDGE/W-CDMA can be prevented using a digital low-IFreceiver architecture. This improves the receive sensitivity of the handset.

RF designers faceunprecedentedchallenges indesigning radiosfor multimodehandsets.


Call +45 72 11 22 00 or visit us at www.nettest.com/umtsSee us at 3GSM World Congress 2005, stand C9.

Generation UMTS.Monitor them or die.Let’s be honest - future subscribers are going to be tough customers. They’re going to wantthe full range of service options. And they’re not going to accept technical excuses. To remain competitive and generate the best possible return on your UMTS investment,you’ve got to be able to monitor, test, and optimize your entire network. You need to knowwhere Generation UMTS is going long before they even get there. We can tell you. Just call.

http://www.nettest.com/umts

Push-to-talk (PTT) representsa golden opportunity formobile operators to deliverinnovative services based onstandardized mobile technol-ogy that can be adapted andreused for a range of futuremobile multimedia services. Ithas the potential to become amajor new revenue source forEuropean operators, providinga way to boost traffic on theirexisting data networks withoutthe need for large up-frontcapital investment.

PTT services enable mobilephone users to communicate“walkie-talkie” style with indi-viduals or groups of people.Commercial PTT services areavailable in a number of mar-kets, especially in the US. Else-where, activities are still morefocused on trials and small-scale service introductions. The wider global uptake of serviceshas been held back by the preponderance of operator-specificservices, a limited number of handset suppliers, and the fact thatsometimes a new dedicated radio or core network must be set upto offer PTT. To overcome these problems, operators mustdeploy systems that address the vital issues of interoperability,end-to-end performance and potential for future developmenton their existing networks.

PTT technology is now entering standard GSM/GPRS/EDGE, W-CDMA and cdma2000 networks via the relativelystraightforward introduction of application server, signalling,subscriber management and media-handling functionality inthe network. The relevant equipment can be installed in thesame rack. However, there are a number of critical factors thatmust be addressed in order for PTT services to be a long-termmass-market success.

Achieving the standardization and interoperability of PTTtechnologies and equipment is a fundamental requirement forsuccess. Several different PTT systems have been rolled out so

far, but they have not followedany standard, and therefore donot support interoperability.While users may be happywith their service today, therecould be serious problems onthe horizon. Users of propri-etary PTT systems are oftenrestricted to handsets from onemanufacturer, and are unableto interconnect with otheroperators’ networks. Operatorswith these proprietary systemsmay find that compatible net-work equipment is availablefrom one vendor, and ulti-mately they could be limitedin their ability to expand ordevelop PTT services.

The industry began toaddress these issues in August2003, when several leadinginfrastructure and handsetvendors proposed a new multi-

vendor open-industry specification called PTT over Cellular(PoC). This was done in collaboration with industry standardsbodies, and the specification was submitted to the Open MobileAlliance (OMA).

Setting standardsThe set of PoC specifications uses a subset of the Internet pro-tocol (IP) multimedia subsystem (IMS), as specified by the3GPP (for GSM/GPRS) and 3GPP2 (for cdma2000) industrybodies, ensuring interoperability and scalability. IMS can also beused to offer new, revenue-driving services, as well as to enhanceexisting ones by adding more IMS components if needed.

Phase 1 of the specifications defines how access-independentPTT services should be implemented in standard GSM/GPRS/EDGE and cdma2000 networks. This ensures that a variety ofterminals can interconnect with a PoC system. Phase 2 builds onthe Phase 1 specification by adding network-to-network inter-connect and presence capabilities. Work is progressing withinthe OMA, and the first release of the PoC standard is based on

3 1P O C


Push-to-talk will reap thebenefits of standardization

Operators must encourage standardization in order to enjoy the financial rewards ofproviding push-to-talk services, explains Niclas Medman.

PTT services allow users to stay in touch at the push of a button. They alsorepresent an important step in the development of voice-over-IP services.


Subscribe FREE OF CHARGEFibreSystems Europe in association with LIGHTWAVE Europe delivers incisive, informed and in-depth coverage of the technology and business issues affecting the specification, purchase and deployment of optical equipment, networks and services across Europe.

FREE subscriptions available to qualifying individuals at fibers.org/subscribe/fse/free/mag.

It will only take a few moments of your time, and means that you could soon be receiving your ownpersonal copy of the magazine.

FibreSystems Europe in association with LIGHTWAVE Europe Dirac House, Temple Back, Bristol BS1 6BE, UK

Tel: +44 (0)117 929 7481 Fax: +44 (0)117 930 1178 E-mail: [email protected]

Europe’s leading information source for optical networking professionals

http://fibers.org/subscribe/fse/free/mag

http://www.openbasestation.org

3 3P O C


the Phase 1 and 2 specifications. The upgradepath from equipment installed today to futuretechnologies is of crucial importance to cellularoperators. The lowest-risk scenario is to startwith a Phase 1 PoC installation and then imple-ment software upgrades in a smooth, stepwiseprocess.

It is essential that there are a variety of PoC-compliant consumer products available that areproperly verified and tested. This will ensurethat users can use PTT services wherever theytravel, and that operators can offer a wide rangeof standards-compliant devices to private andbusiness users. But most importantly, PoC stan-dardization is the only way to remove restric-tions on whom a user can contact by supportingdifferent handsets and different networks. Ericsson itself veri-fies terminals that follow the PoC specification through itsMulti Vendor Terminal Verification offering. Solutions compli-ant with the PoC specification will offer broad service availabil-ity that is important for rapid service uptake through bothinteroperability and roaming.

Performance is another key issue. To control call set-up per-formance and latency in relation to PTT services, there are end-to-end network performance issues that should be considered.Using the PoC specification is one way to ensure that PTT ser-vices will perform well today and into the future, as IMS isdesigned for mass-market, real-time multimedia services.

The OMA PoC is based on “always on” packet data technol-ogy (compliant solutions offer near-instant connections forusers and do not use up valuable network capacity as circuit-switched connections would) when users are not actually talk-ing. As an IP-based specification, PoC offers almost unlimitedopportunities for service evolution. Of course, being an IP-based service that uses network resources very efficiently makesPTT a very cost-effective service for the operator to deliver.

For most users, latency is unlikely to be a major issue as longas it is kept below a threshold of, say, a few seconds. Ensuringsuch threshold values, however, will be critical, and IMS-basedPoC systems employ measures to do this. Latency can be mini-mized in other ways, for example through tuning the radio net-work to optimize performance for packet-based voice services.

Operators planning to implement PTT services should carryout a radio network audit to determine how the network willbe affected by the increased traffic over the packet bearers. Thisincludes performing latency measurements to ensure adequateradio network performance.

An end-to-end network performance audit – encompassingeverything from the PoC application server, through core andaccess networks, to PoC clients – provides an objective assess-ment of network performance and behaviour in relation toindustry standards and key performance indicators. As well asmeasuring and analysing the traffic characteristics and servicesto be introduced, the end-to-end audit also helps to ensure thatexisting traffic is considered and protected.

As well as offering more efficient network utilization and bet-ter potential for development, PoC packet-based solutions arealso less costly to implement than circuit-switched ones. The

strategic advisory service company North-stream has calculated that, in the case ofGSM/GPRS networks, the investment requiredin the radio access network for a circuit-switched PTT solution is more than six timesthat needed for a packet-switched PoC solutionwith equal performance.

The potential mass market for PTT is too bigto ignore, and too important to get wrong froma technology perspective. Standardization,openness and multivendor collaboration arevital for success. That is why several vendors,including Ericsson of Sweden, are working toensure that PTT services are not only standard-ized, but that they also meet consumer expecta-tions for ease of use, performance and cost.

The best way to ensure PTT success is to focus effort on keyissues – interoperability, end-to-end performance, and rapid roll-out – that have the biggest overall impact on the uptake of PoCtechnology. To help meet these industry-wide requirements,Ericsson has established PTT hosting centres around the world.These run PoC services for operators and comprise an IMS coreand PoC application server. The company has a global networkof interoperability testing centres, where any manufacturer cantest its PoC-compliant PTT products. A full PoC specificationset and a PoC Test Tool suite are available online from Ericsson.These resources can be downloaded free of charge by develop-ers and manufacturers for design and interoperability testing.

Planning for the futureImplementing PTT services based on the PoC standard willhelp operators to avoid single-vendor dependencies and open upopportunities for roaming and interconnect agreements. Puttingan open, standards-based mobile multimedia platform in placealso helps to reduce the cost of implementing future IP-basedmobile services, through the reuse of IMS components.

The rationale is to introduce multimedia services using thecommon IMS infrastructure and service enablers. This approachconfers the advantage that most of the main IMS architectureelements are already in place, including a rich set of essentialinfrastructure and service enablers. Operators are able to imple-ment a real-time, mass-market system for mobile multimediain service-driven, business-motivated steps. Operators also getan early route to fixed-mobile convergence, without the need forarchitectural changes. The functionality to support new ser-vices and infrastructure will be added to PoC capabilities overtime in order to build up the packet-switched multimedia ser-vice offering in line with market demands, and in accordancewith standards defined by bodies such as 3GPP and OMA.

When operators come to select the technical solution onwhich to launch and develop their PTT services, they shouldconsider the bigger picture. With an open, interoperable, scal-able solution, they can capitalize on the mass-market opportu-nity for PTT services, and have a platform for developing newmass-market multimedia services in the future at minimal costand with the shortest possible time-to-revenue. ■

Niclas Medman is senior marketing manager at Ericsson of Sweden.

Being an IP-basedservice that usesnetwork resourcesvery efficientlymakes PTT a verycost-effectiveservice for theoperator to deliver.


Load Pull and Noise Test Engineers

Multi Purpose Tuner* - MPTMulti Purpose Tuner* - MPT

A precision electromechanical tuner for in-fixture and on-wafer Load Pull and Noise measurements, combining:

Using three independent RF probes, the MPT synthesizes several million impedances at the fundamental and harmonic frequencies.This allows independent harmonic tuning, high VSWR prematching and most other crucial tuner features, all in a single unit.

Focus now offers you the universal

*Patent Pending

Wideband Fundamental and Harmonic tuning without Triplexers or Harmonic resonators

High VSWR (Prematching tuner); more than 100:1 @ 3 GHzMulti-octave coverage in 0.8 - 50 GHz frequency range

MPT is compatible with all Focus application software.Due to its iTuner control, it allows users to develop their own test software using LabViewTM, VeeTM, Visual BasicTM,MatlabTM, C, C++, etc...

Ask for Product Note 79.1603 St. RegisDollard-des-Ormeaux, QuebecCanada, H9B 3H7

Tel: 514-684-4554Fax: 514-684-8581Email: [email protected]: www.focus-microwaves.comThe Expert’s Choice

Additional features:High resolution (95 million or more calibrated tuning points)+

High power (50 W (APC-7), 100 W (N), 200 W (7/16)) Vibration free on-wafer tuning (no horizontal axis movement) TCP/IP (iTuner) control for User developed software+ Calibration time: less than 30 minutes per set of harmonic frequencies

Independent Harmonic tuning of Amplitude and Phase using the MPT (fo=6 GHz, 2fo=12GHz, 3fo=18 GHz)

MPT tuning using vertical probe movement only

New Product Launch

New Product Launch

http://www.focus-microwaves.com

When spectators at the 2004Olympic Games in Athenstried to use their mobilephones, they were often disap-pointed by the poor connectiv-ity. Andrea Casini of the radiofrequency (RF) equipment sup-plier Andrew blames the poorservice on the fact that thevenues did not have a radio-over-fibre distributed antennasystem (DAS). “At the AthensOlympics, network accessibil-ity was poor with a dropped-call rate of around 20%,” hesays. The Sydney Olympics in2000 used Andrew’s BritecellDAS system. “The dropped-call rate was less than 1% inSydney,” says Casini.

At the Sydney Olympics, allthe base stations were housedin one building, and remoteunits were located throughoutall venues. Singlemode opticalfibre connected the remoteunits to a rack of electronicsthat was located with the basestations. “It was a very power-ful system because coveragecould be switched instantaneously between venues, dependingon where the demand was coming from,” says Casini.“Coverage could easily have been provided using a macro basestation, but the problem was capacity, and for this, the radio-over-fibre DAS was the ideal solution.”

Improved efficiencyRadio-over-fibre technology has been around for about 10 years,but is only now beginning to gain popularity. It involves takingan RF signal, converting it to an optical signal and sending itover optical fibre to a remote unit where it is converted back toRF. A key benefit of radio-over-fibre technology is that it sim-plifies the remote antenna unit. Most implementations elimi-nate the need for a local oscillator and related equipment at the

remote end. Most remote unitscomprise an optical-to-RFconverter, an RF amplifier, aduplexer and RF ports. Thelatter are connected to a stan-dard coaxial cable and ulti-mately to the antennas. Theremote units are small, light-weight, easy to install, andmaintain and consume mini-mal energy.

A key feature of fibre-opticsystems is their extremely highbandwidth. This allows radio-over-fibre systems to simulta-neously transport a wide rangeof frequencies and air interfacestandards. These can range,for example, from GSM at800 MHz to wireless local-areanetwork (WLAN) at 2.5 GHz.

Radio-over-fibre is currentlyused to provide wireless cover-age within large buildings suchas airports and corporate head-quarters. While operators areincreasingly focused on fillingcoverage gaps, they are findingthat macro base stations areoften unable to cover these

buildings. This is especially true for 3G networks, which employhigher-frequency signals that have difficulty propagating fromoutdoor base stations to the inside of large buildings.

Today, in-building equipment sales are still relatively lowcompared with macro infrastructure. However, the increase inpopularity of data services in 3G networks, combined with agrowing interest among operators to tap the lucrative corporatemarket, has led to a greater interest in radio-over-fibre systems.The growing ubiquity of indoor WLAN coverage has beenanother key driver for two reasons: WLAN systems can benefitfrom radio-over-fibre connectivity; and the growing popularityof WLAN is forcing cellular operators to improve their indoorcoverage or lose data customers to WLAN providers.

The US-based analyst firm ABI Research believes that in-

3 5R F - O V E R - F I B R E


Demand for indoor coveragedrives radio-over-fibre

Fibre-optic cable will play a key role in ensuring that cellular voice and data servicesare available throughout large buildings. Nadya Anscombe investigates.

Installation of radio-over-fibre equipment: the technology can be used toconnect remote antennas to centrally located base-station equipment.

ANDR

EW


3 6 R F - O V E R - F I B R E

building solutions will exhibit renewed growth after several yearsof relatively flat performance. ABI’s 2004 report In-BuildingWireless Systems predicts that global revenues from in-buildingwireless systems will grow from $664 million in 2003 to$993 million by 2009, representing a six-year compound annualgrowth rate of 6.9%. ABI believes that in-building coverage isevolving from a “nice-to-have” to a “necessity”, because customersexpect voice and data services wherever they happen to be.

Andrew’s Casini agrees: “In my experience, operators are oftensceptical about in-building networks at firstbecause their business case is weak. But oncethe network is in, payback time is always muchquicker than anticipated because until the net-work is in place it was difficult to predict theamount of demand there would be. We havefound that if coverage and capacity are good,people will use the service. For example, thenetworks we have installed in cruise ships,where the base station is connected via a satel-lite link, have proved very popular.”

Radio-over-fibre technology is ideal for largestructures such as cruise ships or large officebuildings. For smaller buildings, the RF signalcan be distributed via coaxial cable, but signalloss is a problem with long cable links.

Historically, the in-building wireless markethas been dominated by passive repeater/coaxialcable systems. In these installations, the elec-tronics and active system components are concentrated at thebase station or repeater, and the signal is distributed via coaxialcable. Recently, active systems based on radio-over-fibre tech-nology have begun to capture a greater share of the in-buildingmarket. Fibre is used to transport digital signals to modularremote units. These contain electronics to convert the digitalsignal to RF, which is then transported via coaxial cables tonearby antennas. In many cases, in-building solutions are nowhybrid systems, which consist of both active and passive com-ponents and feature high-powered DASs.

Lance Wilson, director of wireless research at ABI Research,believes that hybrid systems that will see the most growthbecause they provide an evolutionary upgrade path. “Because in-building systems have historically been passive systems, whenmore data [throughput] is required, logistics often mean thathybrid systems are the best solution,” says Wilson.

ABI estimates that the penetration of radio-over-fibre in-building systems will grow from 18% of the total in-buildingmarket in 2003 to 46% in 2009. Annual passive systemsdeployed are expected to decline in the same time period.

The main obstacle to growth in in-building systems is money,says Wilson. Not the cost of the system, but deciding who isfinancially responsible. “It is often difficult to decide whoshould pay for what and how the profits are split,” he says.There are many people involved – the service provider, thebuilding owner, the tenant and so on. “Most service providersare very reluctant to share profits, but not all buildings are suitedto a network used only by one carrier, especially if there are mul-tiple tenants in one building,” adds Wilson.

These complications are illustrated by therecent move by BT to provide in-buildingGSM infrastructure in the UK. The equipmentwill be installed in private business premises,but would be owned and backhauled by BT.However, BT does not own a GSM licence inthe UK, so the company intends to lease theequipment to GSM operators.

An attractive technologyDespite its growing popularity, it will be severalyears before the radio-over-fibre equipmentmarket reaches its full potential. It is currentlyestimated that less than 10% of very large officebuildings contain in-building systems, but withcontinued demand for high data-rate services,this looks set to change.

And even when all large venues have in-building systems installed, there are many other

applications for radio-over-fibre technology. It can be used inthe implementation of “base-station hotels” where base-stationequipment for a number of cells (macro or otherwise) is con-centrated at one site, and signals are fed to antennas at differ-ent locations. This arrangement can be very attractive in denseurban environments, where cells are closely spaced and it canbe difficult – or very expensive – to house telecoms equipment.Hotels could also facilitate the sharing of base-station equip-ment among operators.

Because optical fibre is immune to RF interference, radio-over-fibre technology is attractive for security applications. Itcan also be used in fixed wireless networks as well as temporarynetworks, for example for the military or emergency services.

So will the next Olympic Games have a radio-over-fibre sys-tem? “I think there is a pretty good chance that the BeijingOlympics will use the latest telecoms technology, and this isradio-over-fibre,” says Wilson. “If I were a wagering person, Iwould bet on it.” ■

Nadya Anscombe is a technology journalist based in the UK.


Free subscriptions are available at:

wireless.iop.org

“I think there is apretty good chancethat the BeijingOlympics will usethe latest telecomstechnology, and thisis radio-over-fibre.”ABI Research’sLance Wilson



3 7P R O D U C T F O C U S


By Joseph Blanda of CEVADigital signal processing (DSP) technologyprovides a clear path forward for addressingchallenges in the development of small,powerful global positioning system (GPS)technologies that have minimal powerrequirements and are capable of supportingall cellular standards including GSM, GPRS,CDMA and W-CDMA. According to WillStrauss, president of US-based market analystfirm Forward Concepts, a DSP-based GPSimplementation benefits the handset manu-facturer as well as the consumer. “It solves themost critical challenges of cost and powerand for the end-user, it delivers a nearlyinstant and incredibly accurate location fix,which is vital for location-based servicesadoption and usage,” he says.

Using industry-leading DSP cores – such asthose produced by US-based CEVA – a com-plete GPS chipset can be produced for lessthan $3. This includes the radio frequencycomponent. A DSP-based solution also min-imizes both the power requirements and theoverall size of the implementation (see figure).

CEVA has developed and implemented theindustry’s first DSP-based GPS technologyfor mobile devices such as handsets and PDAs.Already available for integration into cellularhandsets and other wireless GPS systems, itdelivers instant and exceptionally accuratelocation information to within 5 m outdoors,and reduces the time required to determine anlocation – called the time-to-first-fix – to 2.5 s.In continuous tracking mode, positional infor-mation can be updated up to once a second.

A DSP-based GPS receiver enjoys signifi-cant performance improvements in terms of

both speed and sensitivity. Thanks to sophis-ticated satellite acquisition algorithms, appli-cation processing is minimized.

The system can achieve a time-to-first-fix of2.5 s or faster at a –147 dBm signal level. Thiscomplies with the E911 mandate in the USand with other emergency services standards.At –155 dB, the time-to-first-fix is 8 s orfaster, which is acceptable for location-basedservices (LBS) and location-sensitive services.

An outdoor/open-sky accuracy of betterthan 5 m can be achieved at –130 dBm, andan urban canyon accuracy of better than10 m is possible at –135 dBm. Indoors, 20 mor better can be achieved at –148 dBm. Themaximum tracking sensitivity deep indoors is–158/159 dBm.

Previous generations of GPS receivers werebased on hard-wired components and a cen-tral processing unit (CPU) core. Theserequired higher clock speeds and significantmemory to function effectively. With a DSP-

based implementation, a manufacturerselects a DSP core appropriate for the appli-cation and integrates it into a chipset. Thisreduces both the power and size of the GPSimplementation, freeing up these valuableresources for other multimedia applications.Performance is also enhanced with a reduc-tion in CPU clock speed and random-accessmemory requirements. The battery life of aDSP implementation is up to three timeslonger than previous receivers, even withcontinuous tracking mode when GPS signalsare sampled once every second.

Another key feature of CEVA’s DSP imple-mentation is that it can operate eitherautonomously or in assisted GPS (A-GPS)mode. The latter involves the exchange ofGPS-related assistance data over the cellularnetwork. This is a major improvement oversystems that cannot operate without assis-tance data. In autonomous mode, specialalgorithms for decoding data from low-levelsignals allow performance down to –150dBm.Below this level, assistance data is used toachieve the ultimate sensitivity. In A-GPSmode, the system can operate in either hand-set-assisted or handset-based mode.

Many leading manufacturers are migratingto DSP-centric GPS implementations.CEVA is moving with them, and has recentlyintroduced its 10th generation GPS solution.Among the business areas that have benefitedfrom DSP-centric GPS are mobile terminaland other device chipsets, telematics, road-toll systems and PDAs, with more to come.www.ceva-dsp.com

• Visit CEVA at 3GSM World Congress2005, exhibit stand E16 (Hall 2).

DSP takes GPS to a new level

GLOBAL POSIT ION ING

host processor(net assist/

nav functions)

memorysystem &

peripheralsAMBA BUS

peripheralbus

data bus

inst bus

host I/FUART or DPRAM

UART

data RAM

program ROM

sampleRAM

GPS channels(entire search

space)

CEVA DSPcore processor

(real-timesearch/track)

RF

CEVA’s DSP-based GPS implementation has minimalpower and memory requirements when compared withtraditional CPU-based designs.

Large buildings, urban canyonsand vehicle interiors are placeswhere GPS technology canstruggle to work. Unfortunately,mobile-phone users spend muchof their time in such places, andthis is forcing the GPS industry todevelop new technologies thatcan meet the growing demands ofthe cellular industry. On theapplications side, the growinginterest in compact andintegrated LBS, combined with

the desire among telecomsregulators to require cellularoperators to provide the locationof handsets making emergencycalls, is also driving GPStechnology forward.

For cellular operators, the moreaccurate a positioning system is,the stronger the business case forLBS such as concierge services,road assistance, mobilecommerce and advertisements.For subscribers, prompt andaccurate services add new valueto their mobile devices andimprove their lifestyle. Ultimately,

as long as GPS applications donot adversely affect otherfunctionalities within a mobiledevice (such as call quality orbattery life), users can be moreeasily converted and can becomeGPS users for life.

GPS struggles in certainsituations because the signals aremuch weaker than those fromcellular base stations. A GPS userin London, for example, wouldreceive several radio signalssimultaneously. These signals arevery weak, buried in thermalnoise, and come from four or

more orbiting satellites20 000 km away.

The distance from each satelliteis determined in 2.5 s, and thisinformation is used to calculatethe user’s position to within 5 m.This is done using sophisticatedtrilateration algorithms –trilateration is essentially the 3Dequivalent of 2D triangulation.And to complicate mattersfurther, the received signals mayhave bounced off nearbybuildings or other structures – ormay only result from partialsatellite coverage.

GPS challenges


http://www.ceva-dsp.com

3 8P R O D U C T S


3GSM PREV IEW

Wireless analyser supportsTD-SCDMA 3G standard

The WCA200A wireless communicationanalyser from US-based Tektronix has newsoftware that supports the time-divisionsynchronous CDMA (TD-SCDMA) 3Gstandard. According to Tektronix, designersof TD-SCDMA components can use theanalyser to perform real-time spectrumanalysis using standardized, automated one-button tests. These are defined according tomeasurement methods and limits definedby the TD-SCDMA standard.

The WCA200A combines real-timespectrum analysis and vector-signal analysisto support the development of 3Gcomponents, network and end-userequipment. Tektronix says that this is

achieved by combining real-time spectrumanalysis with high-performance and flexiblemodulation analysis. The triggering,seamless capture and advanced time-correlated multidomain analysis capabilitiesof the WCA200A are said to simplify theprocess of characterizing andtroubleshooting a TD-SCDMA device.

According to Tektronix, the softwareallows the WCA200A to detect all relevantchanges in the TD-SCDMA signal thatoccur during the call-setup and handoverprocesses.Stand B23 Hall 1www.tek.com

Chipset supports seamlessEDGE/UMTS handoversA chipset and software for use in dual-modeUMTS/EDGE handsets will bedemonstrated by Agere Systems at 3GSM.According to the US-based company, theSceptre HPU enables the seamlesshandovers between UMTS and EDGEnetworks.

The product includes a dual-modesoftware core that is based on a GPRS/EDGE protocol stack that has already beenincorporated into millions of wirelesshandsets. The chipset can support UMTSdata rates of up to 384 kbit/s and EDGEdata rates of up to 220 kbit/s. The systemworks in the 850, 1800 and 2100 MHz

frequency bands.The chipset comprises three chips, and is

based on Agere’s Sceptre architecture. Thesize of the chipset has been minimized byintegrating the baseband processing andpower management functions. This highlevel of integration also facilitates the use ofslower clock speeds and reduces the leakagecurrent. This reduces energy consumptionand results in a handset talk time of up to4 h and standby time of up to 300 h.Passionata Yachtwww.agere.com

ZTE debuts W-CDMA handsetportfolio at 3GSM 2005ZTE is launching its latest portfolio ofW-CDMA handset and infrastructureequipment at 3GSM 2005. The Chinesecompany is showcasing three W-CDMAphones at the exhibition – including theF808, which is claimed to be the world’ssmallest 3G handset.

On the infrastructure side, the companywill be demonstrating the 3GPP-compliantV.3 product range. V.3 is said to offer anextended feature range and supportincreased traffic, when compared withprevious versions. ZTE also says that thenew equipment can reduce operatingexpenditures, and offers a high level ofreliability.

V.3 retains all the basic UMTS R99/R4

RFS Optimizer antennasystem eases 2.5/3G roll-outDescribed as a sleek all-in-one cellularantenna assembly, the RFS Optimizer willbe unveiled at the 3GSM World Congressby Radio Frequency Systems (RFS). Thesystem comprises an antenna, tower-mounted amplifier (TMA) and antenna-tiltcontrol unit (ACU). According toGermany-based RFS, the assembly wasdesigned to reduce the cost and timeassociated with cellular base-station siteacquisition and antenna installation.

The one-body tower-top system is fullyassembled and tested at the factory. RFSsays this can reduce site installation times byup to 40% compared with a system thatemploys discrete components. OptimizerPlus can accommodate both RFS and mostother popular commercial TMAtechnologies.

The entire assembly is less than 1.5 kgheavier than an equivalent cellular antennaalone, and less than 500 mm longer.

According to RFS, this ensures that towerand wind loads are kept to a minimum.

Several versions of the assembly will belaunched at 3GSM: high-band broadbandversions operating at 1900–2170 MHz, andmultiband broadband versions covering880–960 MHz and 1710–2170 MHz. Bothof the versions are available with either 1.3

or 2 m antennas.RFS is also unveiling a new high-

performance micro base-station antenna.The Optimizer operates in the 1800, 1900and 2100 MHz frequency bands and is0.7 m in length.Stand G2 Hall 2www.rfswor ld.com


http://www.rfsworld.com

http://www.tek.com

http://www.tek.com

http://www.agere.com

http://www.agere.com

http://www.zte.com.cn

Millimeter-wave MMICs offer serious growth potential for device andmodule manufacturers. Commercial Applications for Millimeter-WaveMMICs, a new strategic report from Institute of Physics Publishing, willprovide you with crucial information on the new markets opening up for millimeter-wave technology.

The next big challenge will be to deliver packaged and tested parts that meet theperformance, cost and size criteria being demanded by commercial end-users.

This report will provide you with an insight into the time and resources required forMMIC design and evaluate the emerging technologies being investigated by designersand manufacturers, at both the device and subsystem levels, to deliver millimeter-wavesolutions to the commercial marketplace.

TechnologytrackingNEW REPORT

Order the report before31 May 2005 and get a FREE copy of the

CS-MAX 2004conference proceedings

COMMERCIAL APPLICATIONS FOR MILLIMETER-WAVE MMICS

FREE CS-MAX 2004 CONFERENCE PROCEEDINGS WITH YOUR ORDER OF:

OVER 150 PAGES

OF ANALYSIS AND

COMMENTARY

Give your company the competitive edge… place your advance order today ✔ Yes, I would like to order a copy of Commercial Applications for Millimeter-wave MMICs.

I understand that I qualify for a free copy of the print version of CS-MAX 2004 Technical Digest and would like to receive a copy.Please circle the rate that applies to you. Corporate price £995 $1795 ¤1420Academic institution price £895 $1495 ¤1180

I would like to pay by:Please charge to my credit/debit card

Visa/MasterCard/Amex

Card number

Card expiry date

Signed

Date

Please invoice me/my company forCheque enclosed for made payable to IOP Publishing Ltd

Return to us today Fax: +44 (0)117 930 1178Post: Technology Tracking, IOP Publishing Ltd,

Dirac House, Temple Back, Bristol BS1 6BEE-mail: [email protected]

IOP Publishing may write to you about other services and products that may be of interest. Tick this box if you do not want to receive such information. Tick this box if you do not want to receive such information by e-mail. IOP Publishing Ltd may occasionally pass your details on to other reputable companies whose products and services may be of interest. Tick this box if you do not want to receive such offers.

Name

Job title

Institution/Company

Dept.

E-mail

Address

Postcode

Tel.

Fax

FREE

CS-M

AX

2004

confe

rence

proc

eedin

gs


4 0 P R O D U C T S

features of V.2, and provides anevolutionary path to future UMTSstandards based on the Internet protocol(IP). As such, it uses complete andoptimized IP software/hardware structures.Other advanced technologies and featuresinclude support for omni-transmitter sectorreceivers (OTSRs), four-fold receivers,transmission diversity and high-speeddownlink packet access (HSDPA).

The V.3 range of base-station equipment isavailable in macrocell and microcell versionsfor indoor and outdoor environments.Remote RF units and baseband poolingtechnology are also available.Stands H1 and H2 Hall 3www.zte.com.cn

Antenna modules reducecost and complexityDescribed as a range of fully integratedradio antenna modules, the Radionovaproduct line will be exhibited at 3GSM byAntenova. The UK-based company says thatthe modules can be used to reduce the costand complexity of mobile phones andwireless-enabled electronic devices such aslaptop computers.

The modules combine Antenova’s HighDielectric Antenna (HAD) technology withall the required RF components. Theantenna is highly resistant to the detuningeffects of nearby components, and thereforethe same module can be used in a numberof different product designs. The antennawill also operate within multiple frequencybands. According to Antenova, theseproperties provide both maximum designflexibility and the low-cost advantages ofusing a standard component.

The first module covers the GSM bands,and this will be followed by components forUMTS and WiFi applications.Stand E40c Hall 2www.antenova.com

Advanced architecturesupports VoIP requirementsUS-based Continuous Computing will beshowcasing its Advanced TelecomComputing Architecture (ATCA) productsat 3GSM. The core-network systems aresaid to allow cellular operators to address theperformance and scalability requirements ofvoice-over-IP and 3G networks.

The technology is designed for use in thedevelopment of a range of network elementsincluding mobile switching centers,signalling gateways and home locationregisters. ACTA components can also beused to create serving GPRS service notesand gateway GPRS service nodes.Stand D4 Hall 2www.ccpu.com

Dual-band amplifier coversEDGE and HSDPA interfacesTriQuint Semiconductor will be exhibitingits TQM7M6001 dual-band UMTS poweramplifier module (PAM) at 3GSM. Thedevice can be used to create the multimodehandsets that use one antenna to deploy theGSM, EDGE, UMTS (compressed mode)and HSDPA air interfaces.

The PAM employs an innovative biasingcircuit, which is optimized for low idlecurrents below 30 mA. According to US-based TriQuint, this results in increasedhandset talk time in the UMTS mode. ThePAM has a minimum output power of27.5 dBm, which offers ample margin forfront-end losses. This can be exploited todevelop cost-effective multimode phonesthat support compressed-mode handoverbetween GSM/EDGE and UMTS networks.

The PAM offers a linearity that is 7 dBbetter than ETSI-requirements for UMTS.This could be used to support future airinterfaces.Stand J69 Hall 3www.tr iquint .com

Triband modules use Matrixto determine locationThe ITM338 and ITM339 tribandGSM/GPRS modules from TTPCom willbe on show at 3GSM. Designed for use in arange of wireless terminals, includingmachine-to-machine applications, themodules employ Matrix location softwarefrom UK-based Cambridge PositioningSystems (CPS).

According to CPS, Matrix can determinethe location of the terminal to an accuracyof better than 100 m. The modules useexisting GSM network infrastructure totransfer handset location information to thenetwork using standard GPRS or SMSprotocols. CPS says that this results in asignificant reduction in the cost of rollingout a high-accuracy mobile locationtechnology. Matrix also works effectivelyindoors and in urban environments wheresatellite-based systems struggle.Stand C21 Hall 1 (CPS)Stand A3 Hall 1 (TTPCom)www.ttpcom.com

USIM card boosts phonehandset memory capacityDescribed as the the first USIM card tocombine 128 Mbyte of secure, high-capacitymemory with high-speed data protocols formultimedia data, the GIGAantIC USIM isa new release from Oberthur Card Systemsof France.

The card employs MegaSIM memorytechnology from US-based M-Systems, andwill be formally launched and demonstratedat 3GSM. Offering about 1000 times thememory capacity of a standard USIM, theGIGAantIC is said to provide astandardized, easily accessible andtransferable memory resource. This,according to Oberthur, alleviates the needto design additional card slots in handsetsand card bundling in smart phones.

The USIM offers a number of smart-cardsecurity applications, including digital rightsmanagement, encryption, and randomnumber generation. High-speed dataprotocols such as USB and MMC aresupported, and the USIM is backwardscompatible with previous cards. The cardswill be commercially available in the secondhalf of 2005.Stand E48 Hall 2 (M-Systems)Stand B36 Hall 1 (Oberthur)www.m-systems.comwww.oberthurcs.com


3GSM PREV IEW


http://www.zte.com.cn

http://www.antenova.com

http://www.ccpu.com

http://www.triquint.com

http://www.ttpcom.com

http://www.m-systems.com

http://www.oberthurcs.com

4 1P R O D U C T S


3GSM PREV IEW

New mobile handset testercovers W-CDMA terminalsThe 4400 series of mobile phone testersfrom Willtek Communications of Germanynow supports the call-mode testing ofW-CDMA terminals, thanks to a newsoftware option. The 4467 W-CDMA/UMTS Call Mode Option allows handsetservice centres and manufacturing facilitiesto perform a final test on 3G handsets toensure that they are fully operational beforeleaving the factory or repair station.

The Call Mode Option supports a rangeof transmitter measurements includingpower, modulation quality and variousspectrum-related measurements. The 4467also performs receiver measurements, whichensure the quality of the radio receive pathof the wireless terminal.

According to Willtek, the new optioncomplements the 4466 W-CDMA/UMTSNon-Call Mode Option, which is used forcircuit testing and alignment.

Described as a future-proof platform, the4400 series of testers are compatible withfuture technologies such as HSDPA. Asingle instrument can test phones operatingon a wide range of cellular standardsincluding GSM/GPRS/EDGE, W-CDMA,TD-SCDMA, cdmaOne and 1xRTT.Stand B27, Hall 1www.wi l l tek.com

3G network optimizationsystem is automatedActix has launched a version of its 3G RVSnetwork optimization system thatautomates the diagnosis and prioritizationof network problems. The system thenrecommends an appropriate resolution toany problems detected, and engineers canconfirm the diagnosis and proposedresolution at the click of a button using thesystem’s powerful visualization tools.

According to UK-based Actix, thisautomated facility introduces software-basedintelligence into the process of rolling out,

troubleshooting and optimizing 3Gnetworks. This allows network operatorsand infrastructure vendors to accelerate thenetwork rollout process. The system couldalso be used to develop best-practicemethods for teams performing diagnosticsand troubleshooting.

The automated system addresses manyoptimization parameters including droppedcalls, setup failures, missing neighbours,pilot pollution, poor coverage, systeminterference and handover issues.Stand A25, Hall 1www.act ix .com

Integrated handset basebandcovers EDGE and UMTSAn integrated handset baseband thatsupports UMTS and EDGE is a newproduct from Comsys Communication andSignal Processing. The UEware multimodebaseband will be unveiled at 3GSM andsupports UMTS voice and data, GSMvoice, EDGE multi-slot class 12, type IImultimode, dual transfer mode and HSDPA.

According to Israel-based Comsys,UEware employs a scalable architecture andstandard interfaces so that chipset vendorsand device manufacturers can reduceproduct development costs and time-to-market. The baseband is said to deliveroutstanding receiver performance, andoffers easy integration with any UMTSplatform and protocol stack.Stand D7 Hall 2www.comsys.co. i l

New chipset is compatiblewith EDGE and HSDPAThe new Mobile Station ModemMMSM6275 chipset from Qualcomm iscompatible with the HSDPA and EDGE airinterfaces and also supports GSM/GPRS andW-CDMA. The MMSM6275 delivers peakdata rates of 1.8 Mbit/s and is part of US-based Qualcomm’s Enhanced MultimediaPlatform, which includes integrated chipsetsthat support all major air interfaces.

According to Qualcomm, the EnhancedMultimedia Platform chipsets are software-compatible to ensure that advancedmultimedia applications can be deployed ona range of handsets and network standards.

The MSM6275 is based on Qualcomm’sradioOne zero intermediate frequency (ZIF)architecture, which is said to ease thedevelopment of small, low-cost, multibandand multimode handsets. This chipset also

integrates Qualcomm’s Launchpad suite,which supports a range of application-related functions including advancedmultimedia, multimode-assisted GPS, userinterfaces and removable storage capabilities.Stand A2 Hall 1www.qualcomm.com

Analyser troubleshootsCDMA and GSM base stationsNew from Anritsu of Japan, the Cell MasterMT8212B adds a CDMA/GSM transmitteranalyser, interference analyser, built-insource, channel scanner, and DS0/VFchannel access to the Cell Master line ofanalysers. According to Anritsu, theseadditional test capabilities provide RFengineers and field technicians with ahandheld instrument that can be used toensure proper deployment, installation andmaintenance of GSM and CDMA networks.

For GSM applications, the instrumentcan conduct traditional RF power andfrequency error measurements, and can alsodisplay time slot information on GSMsignals. The analyser can make all major RFmeasurements on CDMA signals includingchannel power, frequency error, occupiedbandwidth and noise floor.

The analyser weighs less than 2.5 kg andis available with optional features, such asan interference analyser that determines thetype and bandwidth of interfering signals. Itis also available with a built-in signal sourcefor measuring the gain/loss of two-portdevices. It can be used for antenna isolationmeasurements and repeater tests.

The spectrum analysis capability allowsusers to locate, identify, record and solvecommunication systems problems in the100 kHz to 3 GHz frequency range. It hasdedicated routines for measuring fieldstrength, channel power, occupiedbandwidth, adjacent channel power ratio(ACPR) and carrier-to-interference ratio.Stand F28 Hall 2www.eu.anr i tsu.com


http://www.willtek.com

http://www.actix.com

http://www.actix.com

http://www.comsys.co.il

http://www.qualcomm.com

http://www.qualcomm.com

http://www.eu.anritsu.com

4 2 T H E F U T U R E

Why is HSDPA such a hot topic?Within the last year, operators have becomeinterested in moving towards what Nortelcalls “wireless broadband” services based oncdma2000 EV-DO and HSDPA. Instead ofjust having a vision, they now have real plansfor roll-out. While EV-DO and HSDPA areon similar technology tracks, DO is ahead interms of time. The technology was launchedin Korea in 2002 and it has changed the waythat people use wireless there. Music is a hugefocus for younger users, while older users bene-fit from practical broadband services.

Is the presence of EV-DO acceleratingHSDPA development?In markets where cdma2000 and UMTS areavailable, DO is certainly becoming an issuefor UMTS operators. As well as Korea, DOis now available in North America, withVerizon offering services in 14 cities. This is abold experiment, but Nortel is optimistic that a strong marketwill form around wireless broadband in North America.

From a technological perspective, DO has much in commonwith HSDPA, including the use of hybrid automatic repeatrequest, adaptive modulation schemes and similar approaches toshared channel use. As a result, HSDPA developers can benefitfrom much of the technology and experience of DO.

The timeframes associated with HSDPA development anddeployment have shortened significantly during the past yearand a half. I think this is a very positive sign for the industry.Because of our experience with DO, we were less surprised bythis than others. Indeed, Nortel has been talking about wirelesshigh-speed data for some time, and we are pleased to see strongdemand in Korea and Japan, where millions of users are payingfor high-quality services. This success has created genuine inter-est in other wireless broadband technologies such as WiMAXand flash orthogonal frequency-division multiplexing (OFDM).

Will these technologies play key roles in 4G networks?4G is about both new high-speed air interfaces and the integra-tion of third-generation technologies. If the industry succeeds inmigrating from DO to DO release A, and from HSDPA toHSUPA, it will be on the right path to 4G.

In terms of new air interfaces, Nortel believes very stronglythat OFDM multiple-input multiple-output (MIMO) canachieve significant improvements in spectral efficiency.Spectrum remains a limited resource, and the success of wireless

broadband services will strain 3G networks.MIMO schemes increase spectral efficiency

by exploiting the multipath transmission thatoccurs in urban (or suburban) areas. A devicesuch as a PDA or laptop computer can employup to four antennas to achieve MIMO.

MIMO works well with OFDM – the twotechnologies seem to go hand-in-glove. Inaddition, we see HSDPA, HSUPA andWiMax all adopting MIMO.

How will UMTS TDD fit in?There has not been very much interest inUMTS time-division duplex (TDD); insteadthe focus is on HSDPA and HSUPA. In addi-tion, I believe that WiMAX has great poten-tial for delivering broadband services, and ifWiMAX can get some momentum, it couldbe a contender in the TDD bands.

While WiMAX will offer some degree ofmobility, it is still unclear how it will fit in

with other mobile technologies. The technology is certainly astrong proposition with Intel behind it, but whether it can gobeyond the fixed realm is another question. WiMAX could alsofind applications in cellular backhaul – including mesh networks.The key issue is whether WiMAX technology can evolve rapidlyenough to complement, or even threaten, DO and HSDPA.

How is the in-building market progressing?Backhaul is still an important challenge in this sector. Whileinterest is growing in UMTS picocellular equipment, we arecertainly not seeing large deployments at the moment. A lot ofdevelopment activity is currently happening in voice-over-WLAN systems for both homes and businesses. We are seeingprototype dual-mode WiFi/GSM phones, and significantprogress has been made in addressing issues within the 802.11standards that could hinder voice services. Although it is still notperfect, WiFi has progressed to the point where it is a viablealternative for providing indoor coverage, in terms of capacity,security and quality of service.

There has been a move away from the concept of usingBluetooth for in-building telephony. The wide acceptance ofWiFi, its low cost, and improvements in the standard make itmore attractive than Bluetooth. The challenge is to ensure thatWiFi and cellular networks work well together in terms of hand-off and transparency of features. ■

Interview by Hamish Johnston, editor of Wireless Europe.


Wireless broadband comes of ageJohn Hoadley, vice-president for advanced wireless technologies at Nortel, believes that the cellular

industry is moving rapidly towards the deployment of mobile broadband technologies.

Nortel’s John Hoadley believes that MIMOwill improve spectral efficiency across anumber of air interfaces.


It’s this simple: OEM or network operator,you can look to Radio Frequency Systems for the industry’s most complete array of space-saving, economical base stationantennas, designed to blend unobtrusivelyinto any environment.

But that’s far from all.

RFS is also your source for every kind of site component, including tower-topRF enhancement devices, transmission linenecessities—coaxialcable, jumper, connector,accessories—and filter and combiner elements.

In brief, if you know RFS, you know theworldwide source of system solutions thatfocus on your communication objectives, andthe most cost-effective way to achieve them.

Specialists in antennas dedicated to mobileinfrastructure, RFS is the best source of variable tilt and multi-band versions, and an industry-leading solutions provider for 3G deployment. And every RFS antenna isoptimized for its specific application: PMR,SMR, paging or cellular ... regardless of frequency band and standard.

Radio Frequency Systems.Outstanding customer service, and the assurance of peak network system performance. Visit us at www.rfsworld.com

should you lookwireless solutions?

Where in the worldfor broadband

S O L U T I O N SS I N G L E S O U R C E

T h e C l e a r C h o i c e T M

RADIO FREQUENCY SYSTEMS

UNITED STATES +1-203-630-3311 • GERMANY +49-511-676-2731 • AUSTRALIA +61-3-9751-8400 • BRAZIL +55-11-4781-2433 • CHINA +86-21-5774-4500

©2004 Radio Frequency Systems

Please visit us at

Palais des Festivals, Cannes

14 to 17 February 2005

Hall 2, Booth G2

http://www.rfsworld.com

http://www.agilent.com/view/3ephemt

CONTROL CHANNELS ARE KEY TO ACCELERATING THE DOWNLINK

Technology

Transcript of CONTROL CHANNELS ARE KEY TO ACCELERATING THE DOWNLINK