Satellite Communications Overview College assignment

TITLE SATELLITE COMMUNCIATIONS OVERVIEW

MODULE MSc SATELLITE MOBILE COMMUNCATIONS MBSTCM-N MSc

STUDENT 12028225 John Bofarull Guix jbb025mylondonmetacuk jgb2012skycom

TIME AVAILABLE 4 WEEKS DELIVERY DATE December 10th 2012

CONTENTS Abstract

1 Introduction

2 Key Enabler

3 Satellites Industry

4 Subsystems

5 Services

6 System Examples Skybridge VSAT design parameters GOCE COSPAS-SARSAT Orbcomm SAR scenario

7 Where are the birds

8 Regulators

9 Strategic Sector that includes Big Brother

10 Direct Competition or Synergy

11 Frequency Bands

12 Conclusion Comments References Annexes

ABSTRACT

Modern Satellite Communications are evolving from analog to digital increasing spectral and power efficiency lowering orbits to reduce to microseconds path delay also increasing positioning accuracy offering improved SMS secure business links early missile launch detection targets tracking emergency signaling video-telephony and internet over satellites among many other offered services This sector has all the tools to rival the ground wireless telephone and wireless internet broadband offered by GSM GPRSEDGE 3G and 4G operators yet the broadband over satellite market penetration is really slow at best A minor sector compared in workforce size to traditional ground operators delivering high-end products and services to the Military the Satellite Communications industry would be a clear alternative to offer real competition that would ultimately benefit the end wireless subscribers that we all know phone bills are like car gas bills approx 23rd of the bills go on taxes salaries to people who really have little or nothing to do with your mobile phone calls

Optical fiber mass deployment could have started years ago but now it is rolling out at double to satisfy increasing demand for broadband and at the same time is a safeguard to ground operators to saturate the market demand and prevent an alternative technology like internet access over satellite to achieve a significant market share In this case study I have searched for the current parts of the working satellite systems I also looked for working satellite systems that somehow could evolve to rival ground wireless operators Instead of diving in a specific satellite system as study case that would be limited by patents and proprietary details I start drawing the attention of the reader to a slightly modified 3 segments satellite communications sector where end subscribers enjoy more attention than they currently have In point 6 I have chosen a few systems as examples Skybridge VSAT generic parameters GOCE COSPAS-SARSAT ORBCOM and a generic SAR system Sampling their main parameters helps to understand current status of working systems Prior to mentioning those examples I have shortly looked for Satellite Communications Industry companies and products in point 2 And because despite relative small industry sector size (relative to giant ground wiredwireless operators) satellite communications are key enablers to global wireless networks I looked for details about current situation of one of the obvious business expansion routes of the sector that is offering internet over satellite networks with broadband equal or better than ground wireless operators at competitive fares Just as reference I found where to look for when seeking satellite orientation details in point 7 I have briefly gathered some satellite communications regulatory parameters in point 8 and sketched frequency bands in point 11 It cannot be a satellite communications overview study case without mentioning Echelon point 9 In most of businesses frontal clashes end up causing loss so I checked for satellite ndash ground wireless business synergies finding how every one finds convenient to enjoy satellite coverage for different purposes cellular operators need satellite services perhaps more than they would like to There are lots of details that have been left in the draft folder but I have tried to include as many as possible as annexes to gain overall sector knowledge I have added some additional comments right before the annexes pointed from main text with bracketed reference[ABC] If the reader is going through the electronic version of this document you can readily follow the embedded web links If you want an electronic copy of this document just ask me for a copy jbb0025mylondonmetacuk or jgb2012skycom

SYNCOM 1963 worlds 1st GEO communications satellite 14th of 290 civilian application satellites have been manufactured by BOEING that owns the largest satellites manufacturing factory in El Segundo CA

John Bofarull Guix 12028225 jbb0025mylondmetacuk jgb2012skycom 1 8

1 INTRODUCTION back to contents

Satellite Communications currently have the following 3 segments 1- Space 2- Ground and 3- Control When I think of

the Control segment I cannot avoid seeing it like the service elevator I used in Torrespantildea in one of my service visits bringing in VH602 amplifiers when some one hanged a faulty elevator note on the main elevator that directly reaches transmitters

level 7 floors between transmitters level and highest service lift level So it took me double effort to finish installation The service lift was of capital importance when the tower was being built but it was seldom used once the main lift was

operational

The Satellites Communications industry is attempting to go from the scenario on the left (from referenced literature) to the scenario on the right (I have replaced the control segment with USERS)

Such scenario modification is my attempt to highlight the importance that end subscribers must gain if Satellite Communications are going to get any internet-over-satellite significant market share in densely populated areas already

deeply penetrated by current ground wireless 3G4G and wired broadband access

Satellite communications are key part of the nuclear deterrent that in worst case would spot early ICBM launching allowing retaliation securing mutual destruction Because of the military importance of Satellite Communications the control segment

is factually a doubled network with the control segment holding right to eavesdrop and veto what we the civilians would call the main network Satellite Communications controllers have their own Satellite Communications channels the same way they

have their own airports and seaports bases The military do not have real interest in allowing mass satellite communications developing at least not in the same way that GSM started for instance They already allowed ARPANET to mutate to the

Internet why should they allow another spin-off that would only benefit civilians with real competition among operators The

traditional ground TV broadcast sector has also suffered from such regulatory attitude TV broadcasters used enough spectrum potential to offer same or even more broadband capacity compared to ground wireless communications but ground

broadcast industry never realized to see military mobile communications technological spin-offs take the stage along with most TV broadcasting spectrum eventually (DVB-T2 switch over) GSM 3G have centralized product development

investments there are many trendy mobile phone handsets with tablet and laptops incorporating wireless modems but

satellite mobile equipment still needs a small cumbersome dish or foldable cucumber-like antennas

Fierce enough is the competition among ground wireless and wired broadband operators so they remotely consider allowing yet another technology on what they consider their backyard the cellular market in densely populated areas Fierce but

wolves team up when intruder arrives Certainly there is increasing synergy like DVB hybrid networks and assisted GPS (A-GPS from Spirent) and some dual satellite mobile equipment able to directly route traffic to ground wireless base stations in

case of no coverage or better broadband service on the ground than over satellite But one thing is to use the GPS to relay

back position saving base stations to do so and the other one is to give up revenue

Satellite Communications are best or only choice at sea in desertedmountainous areas (oil rigs) and some rural and remote environments where it is too expensive to bring the copper pair to subscribers or there is poor or no ground wireless

coverage

The term Satellite Communications here refers to any wireless technology usage on satellite embarked platforms broad

sense including agreed full duplex channels for a video conference for instance down to the eavesdropping of mobile phone base stations and SIGINT telemetry sensors data relay broadband networking and imagery for instance

2 KEY ENABLER back to contents

Satellite communications started as an exclusively military tool expanding to mass analog TVradio broadcasting and long distance analog telephony in a similar essential way that Arpanet became the early model to develop the Internet Digital

communications offer essential advantages compared to analog among the most important ones Back Off margins reductions because platforms can be operated on saturations versatility to process data through software not hardware only

and the ability to reconfigure such processing without having to hardware recalibrationupgradingreplacing The basic satellite communications ground terminal chain is Transducer ADCDAC Codec Energy dispersal (the well known

sawtooth signal for analog TV or array line-writing row-reading in digital) Outer Coding Convolutional Coding Inner

Coding WaveformPulse Shaping (Mapping) Filtering (IF or direct Modulation [Annex29]) Power Amplification Combining and Antenna Matching Example of main communication chain parameters for INTELSATEUTELSAT TDMA in

[Annex28] Modulation can take place as on baseband production of for instance the COFDM carriers and then modulating the whole block to the nominal RF carrier on the allocated channel or a QPSK signal can be directly locate the constellation points

within the RF channel Specific coding parameters related to Satellite Communications included in [Annex27]

Some of the solutions that the Satellite Industry supplies to the military are Secure Military Communications (enablingdisabling channels of any kind with robust coding and cryptography to manned or unmanned platforms (UAirV

UMaritimeV UGroundV in short UXV) any coding any modulation at any time under any weather) SIGINT tracking passive and active microwave radar and equivalent optical LIDAR and targeting

Satellite communications relatively recent improvements offer navigation improvement and broadband access to maritime

and air traffic highlighting the limited accuracy of traditional navigation systems like inertial (example Vectornav yet needs

calibration and the device is far more expensive that a cellular like device) LORAN (US federal LORAN switched off StarNews December 2012) and TACAN (intro and main drawback concisely explained here) compared to GPS Dont ask me about

GLONASS (GlobalSecurity intro) or Galileo (700kgsatellite expected operative 12 years 1421355kW(eclipse) orbit altitude 23222km i=56ordmGSA doesnt give many details and forecast report) because I guess that if the market success they forecast

to achieve does not happen they can always try impose fines one competitors who have honestly won customers trust for

more details on such dictatorial tics have look to outrageous recent fine on Microsoft The Satellite communications industry (SIA links) is evolving on 2 directions 1st taking warfare to scenarios and offering

possibilities only dreamt of 60 years ago Nothing will ever replace the foot soldier taking control of a perimeter but infrared 247 all-weather real time control of areas ranging from small battlefields to entire cities including ground penetrating radar

and LF channels to underwater systems such technologies make a difference between victory or defeat Such relatively new technologies have allowed to further reduce needed percentage of troops committed to the front line [JKG book] Air fire

power is the successor to ground artillery and full control of air surveillance denying the enemy such capacity may render

entire armies and navies defenseless 2nd additionally there is partial success in a steady penetration of civilian security applications and internet access over satellite Satellite communications are

a success at almost monopolizing sea desert mountain communications or wherever the twisted pair is too expensive to reach or nearest ground base station too far to offer coverage

quite a success on law enforcement support Intelligence agencies have gone from how do I get intel to

How do I process the incoming raw data onto intel the gaps have been covered sometimes painfully noting that there will always be need for the ground platoon ready to pull in and the attentive eye monitoring computers that cannot

possibly make some decisions not until they may be considered human that knowing humans it will never happen Limited success in supplying global wireless mobile equipment to businesses yet the ground mobile operators cannot

afford giving a single inch of market ground

A couple of specific recent updates that highlight above mentioned Satellite Communications 1st trend

1- On November 12th 2012 US Navy Admiral Joe Sestak online NBC News interview mentioned that US president B Obama had just been appointed a new 4 start general to space command While I did not find the name of the promoted general

I found November 2011 US Senate nominations page 148 space command nominee declarations that show US military trend to bring more satellite communications availability to the front line soldier and put to keep pace with satellite

communications developments like M code enabled GPS receivers (M code successor to P(Y) code sent in L1 L2 GPS

downlink signals link to GPS details in Services) that are already available but Army procurement seemed at the time of declaration not having made such terminals available as widely as expected

2- On November 20th 2012 the IET Savoy in London hosted a Sonar display update including presentations from Atlas BAE (SSPARS PARCS GEODSS) Thales (EUTELSAT) and Ultra (TECB) With an increasing amount of Navies embarking more

and more sensors as well as higher and faster data processing capacity required with smaller quieter and more

numerous threats at sea and from air to spot track and be able to destroy the volume of information is increasing thus satellite surveillance tracking communications and targeting is more strategic than ever

I mention the quiet service because Satellite communications offer sea platforms communication services as if they were on the ground lifting traditional sea embarked communications limitations where every embarked pound must be of use or

thrown overboard Air power and Submarines keep sea trade safe therefore supplying secure communications to those working on the edge of technological demands makes sure that whatever happens in between will be somehow under

control John Bofarull Guix 12028225 jbb0025mylondmetacuk jgb2012skycom 2 8

Submarine acoustic arrays have increased from hundreds (elements) per vessel to thousands There is so much

information that early operators listening only is no longer working on regular basis Despite higher processing power on

board there is also need to keep backhauls for additional processing support in order to process incoming data on time to make the right decisions The UK and the US are heavily relying upon satellites to support armed forces But under budget

constraints less efficient tools face removal from active duty for example the outstanding Nimrods that stopped service because despite their usefulness satellite surveillance covers far more area at less cost

As Mr Sestak pointed out maritime warfare trends depart from Red October like hunting and it is evolving towards scattered sensors picking up signals and relaying SIGINT back to C4 nodes Satellites are the eyes and ears and despite as expensive

as they are no modern armed forces consider possible long term successful defence or abroad operations without controlling

satellite communications Electromagnetic spectrum is considered by governments a strategic asset the perfect excuse to grant themselves exclusive

control over it and outrageously bill any civilian attempting to use with ludicrous purposes Any ham radio enthusiast knows that the higher the rod the more signals (as well as interference and noise) will be picked if front end sensitive enough

among other requirements But for the same reason satellite communications are inherently superior in area coverage to any

other means of ground wireless communications Improving spatial resolution if close enough the shortened delay from GEO to LEO allows real time monitoring of all sorts of wireless communications from car engines ignition heat from combustion

motors underground water and gas pipes buried metal structures to and any kind of mobile base station signals spinning HDD RAM traffic CRT or LCD or liquid display charging Such extensive monitoring is being performed by ground base

stations

In 2009 the Satellite Industry generated $26161 Billion Satellite communications involved a 4 of the world overall yearly

worldwide communications figure Apparently a minor component in money volume compared to the overall telecommunications industry moving trillions of dollars yearly the satellite communications sector is a key enabler (like optic

fiber manufacturing UHF broadcast transmitters manufacturing and ground mobile base stations manufacturing these enablers are small in specific departmental company size or money volume for themselves but their products move those

trillions) My reasoning to argue whether satellite communications has the potential to one day achieve more mobile users

than for instance current ground mobile communications goes as follows Because satellites monitor mobile communications and wireless signaling in a broader sense and the majority of

countries with large volumes of wireless traffic share control of the main data monitoring pools where all wireless communications security screening takes place through multi-disciplinary and international teams every involved

government wants satellites to carry on and develop accordingly to protect their interests You get what you give Such global communications control effort rewards contributors with satellite feeds among

other benefits It is rather expensive but power corrupts and power over communications is top currency among

governments Governments keep monopoly over majority of control segments Power corrupts If something can happen and

you let enough time to happen it inevitably and eventually happens [EC] economic control requires communications control satellites pick almost everything that goes wireless So if controllers keep tampering economic circuits by

deliberately keeping growing inflation investing as much as possible on grounding communications inflating prices with

always growing taxes there is no foreseeable way to remove such yoke Therefore satellites and satellite communications like air carriers at sea like air squadrons like the nuclear deterrent

(ICBM bases and mobile units submarines) and other cornerstone factors that strengthen governments are of paramount importance (to those governments) are strategic assets Such assets are key to survival a must-

investment for those who have margin to invest Then you have those who think they have margin to invest on such

expensive technologies but they dont really have the money to invest incurring debts that drag entire countries to bankruptcy and factual economical slavery to foreign actors

Satellite embarked platforms have limited physical capacity compared to the operational capacity of wired local exchange

stations compared to mobile operators MSC and compared in general to busy data centers with their spacious buildings that in many cases didnt cost a penny to recently privatized operators How many KWh of electrical power does a data centre

with 1000 server blades need to satisfy a big city internet demand on peak hour What fraction of that electrical power

consumption goes to keeping those servers within room operating temperature and humidity working conditions Its at least initially less expensive for computing power to be kept on the ground that in outer space temperature wider span alone out

there readily kills the majority of standard ground working electronics The Tons of racking steel and copper wiring alone make it impossible for satellites to embark the same systems at least as we currently know them Satellite points of view are

achieved at far higher cost than erecting ground base stations Launching prices have been reduced satellite sizes have

also evolved to accommodate requirements ranging from fist like cubes to sizes of double decker buses (body only without panels) and then we have the International Space Station However despite ground base stations cheaper installation costs

compared to launching rockets again compared against ground base stations incur regular costs like significant payment to private properties to use such roofs the electrical bill regular monitoring on site and other factors where satellite platform are

more efficient than ground stations Ground mobile operators need far more base stations than satellites needed by satellite communications operators to cover

same area Currently satellites are 1st choice in remote areas where traffic is low and where other access technologies

installation is too expensive compared to hanging a satellite dish or not even that just purchasing a mobile phone like modem

So it makes sense that best option is to keep power hungry circuits circuitpacket switching and processing equipment on

the ground where it all is right now and only embark enough transponding capacity to be able to pick up any wireless signal

and as many wireless signals as they may be produced within the specific areas to service Although satellite communications are of capital importance to the military something else is whether a predominantly

military controlled sector may eventually gain a significant market share (without eavesdropping or convincing the end customers to pay 23rd overhead on top of the service) in for instance ground wireless mobile communications in densely

populated areas generating regular huge volumes of traffic One thing is to be able to tell when a computer HDDs start spinning or sample wireless waves generated by base stations tofrom mobile equipment things that satellite

communications can do and as a matter of fact regularly do (read about Echelon for further reference) the other thing is to

be able to offer a reliable service under heavy traffic pressure with high availability no matter the amount of users simultaneously attempting to access such service

Satellite communications succeed over ground communications where other means of communications would be too

expensive for the simple fact that wireless channels save operators trench digging and cabling operations that cost most

of times same or higher order of magnitude that everything else in the project balance sheet Aircrafts and maritime traffic control as well as spectrum usage control is easier the higher the antennas used In underdeveloped areas or

fractured territories where small countries find it difficult to agree upon common infrastructure (Africa) communications satellites offer the meeting point that could bring to end armed conflicts and eventually help 3rd world development There

are efforts on this direction but ground wireless operators seem to always get ahead with petty cozy socialists-like-it small scale projects that saturate the investing possibilities of already reluctant clients not leaving much room for an alternative

access technology like satellite communications

As mobile communications antenna riggers well know the higher the mast the more radio signals and noise picked up So initially GEO and then 2 to 3 orders of magnitude closer orbit satellites (MEO LEO) offer the perfect base station masts may

be expensive but the basic cell area is enhanced from perhaps 10mi with masts on the ground to 3000km or more

(SKYBRIDGE) As former antenna rigger myself you cant avoid thinking that you dont have to climb towers to hang radiating systems any more From pulleys having to manually heave parts and long shifts hanging on towers to launching

rockets if I had the choice to me it would be clear If back to 90s a single satellite was able to offer 120000 telephony

channels a network of modern low orbit chains with real time hand-over may be even a cheaper alternative to mobile phone operator offered costMBps most of them refusing to give up the annoying monthly download allowance limit on end user

TV+telephone+broadband monthly bills However to the question Could a combined GEOMEOLEO satellite communications network on its own satisfy

the current and future COMPLETE demand of broadband communications traffic My answer is no ndash wired access

(POT pair ISDN ADSL fiber to nearest street cabinet or to homes) is wining the broadband offer in high density population areas They already succeeded at lobbying governments to partly pay the deployment bill of the networks they operate with

public money Even if an affordable network of satellites could be deployed tomorrow offering ultrafast broadband at lower price than that offered by BT Infinity the market inertia has been already been pushed towards increasing optical fiber

market penetration Satellite communications may satisfy particular needs from some global corporations and transport

networks (FedEx DHL Post Office railwaybus networks) or individuals and communities like farmers and fishermen Markets like diversity but as useful as satellite communications are to oil riggers ships and aircrafts making the market shift would

happen at a too high cost If ground wireless operators were sloppy on service offering poor coverage using obsolete or faulty technologies such

shortages would have been a factor to help in an alternative as satellite communications to take a significant market share But ground wireless operators are quite the opposite they and keep their main effort at making sure they control the best

tools keep their coverage maximized and keep enough unused overhead traffic capacity to satisfy traffic peaks [ML][JQ]

Possible breach GNSS is already embedded in the majority of cars and mobile phones I will detail later on

I have also read about trials to embed nano-manufactured GPS+GSM systems in shoes clothes gadgets even trials in human

bodies What is going to be next mass smart watermarking by smearing clothes and food with mild radioactive short life

isotopes traceable from satellites) so we show up as fluorescent dots of interest on display The satellite communications sector is undergoing optimization do more for mess However Asian dragons along with European+Russian copy machine

minded engineering sectors heavily funded by their respective governments they do not think it twice when it comes to cut costs regarding developing their own satellite capabilities

Ground wireless communications is a cut-throat industry that generates huge revenues It is difficult to penetrate markets where current operators have reached full coverage with satisfactory levels of service Mobile communications keep releasing

technology upgrades They are constantly evolving to improve offered services and bandwidth despite many agree that

current ground wired and wireless mobile communications are too expensive Rewording in ground mobile communications substantial chunks of end user bills dont really go to maintainingimproving the network or enhancing terminals but to

operators revenue that ends up as taxes the operators pay to regulators arguing spectrum high demand justifies high regulatory costs shaped as spectrum licensing monitoring costs and products compatibility acceptance tests Some see

outrageously priced licensing as the reason why regulators slow down technological evolution that from the point of view of

the majority need not be so quick because of the costs that would incur money that has to be kept in operators accounts for bankers to make their benefits bankers that turn out to be the owners of the operators


3 SATELLITES INDUSTRY back to contents

The satellites business and particularly satellite communications equipment supply is an 80 USA business US Satellite

manufacturing staff quality rating is well ahead of EU+Russia counterpart despite Europe+Russia has same order of

magnitude of staff dedicated to Satellites businesses The EU+Russia lobby is beefing up their respective Satellite related industries many times building facilities buying really expensive tools and creating jobs filled by staff who need at best more

training to catch up with US counterparts In 2010 the US satellite industry made 70 of the overall market and Satellite TV was 80 employing over 243000 but there has been a 75 staff reduction in some areas

Among the three Satellite industry groups 1 manufacture 2 launch and 3 services The manufacturing satellites work

force heads count remained virtually constant and the sector is reporting increased benefits so technological improvements are allowing a reduction required work force that is more optimization than sector shrinking Its business after all Whatever

technological improvement is not invested on creating more jobs that might turn up meaningless but it is translated into more benefit with same amount of people on payroll The satellite industry is slowly winning market ground not losing it

With roughly similar amount of heads in workforce Satellite communications industry makes more money which is characteristic to increasing efficiency Satellite Industry has specialized financing companies like Near Earth

Some key players are Boeing Northrop Grumman CAST EADS-Astrium IAI ISRO ISS-Reshetnev Lockheed Martin Mitsubishi Orbital SSL Surrey Thales Alenia Satellites related Industry comprises specialized companies in the following

technologies Antennas Modems RF parts OMTLNBLNALNC Network Management Software Ku band systems C band systems X band systems Ka band systems

Some SATCOM-II US government project related companies AEP Networks C-COM CACI Eutelsat America GlobalSat

LLC Helius IMC Intelsat (Satellite Ventures SkyTerra )LightSquared MotoSAT SES Americom Thuraya XTAR LLC

Lets now have a look to Satellite sub-systems following the segments mentioned in the introduction The overall cost figure

of merit Costpixel embarked systems is being reduced (similar to cost(in^2 SiO) for waffles to produce chips) which is good

4_SUBSYSTEMS back to contents

Satellite communications are basically transponding platforms transparent (repeaters or in TDMA-only mode not far from

basic RF hot-bridges) or with Time Space switching and processing capabilities (TS network configurations from telephony exchange stations) including BER improvement down to bitsymbols recovery The payload [Annex89] is embarked on

launching vehicles once deployed these platforms orbit around the Earth (read annexes for mechanics equations to remain

orbiting) along with lower g[kgms^2] vacuum and harder operational conditions than on Earth On the spin stabilized satellite example there is a section of the main cylinder that keeps spinning to help the satellite stay on orbit

41- Space segment

All support sub-systems comprised by frame power supply (may include nuclear power cell) batteries

thrusters solar panels navigation and telemetry (interfacing with control on Earth) attitude control (on board yaw pitch roll control) temperature control (may include split cooling configuration with liquid Mercury as coolant I include in

[Annex20] a table of possible cooling liquids showing operational temperature ranges Basic reliability rates table in

[Annex26] Some 90s communication satellites with onboard processing capabilities table [Annex262]

All these subsystems support the communications payload the transponder Besides vacuum space radiation

exposure) and solar wind (Sun photons behave like wind on solar panels slightly pushing GEO satellites away [Annex42]) among any other outer space factor from the electronics point of view operational temperature ranges are of capital

importance the starting point to choose components to build a working prototype Following real temperature operational

ranges required for different subsystems min[ordmC] max[ordmC] Electronic equipment and battery temperature ranges mentioned on the left

apply on stand-by mode only When operating both ranges narrow down to

[+10+45]ordmC and [0+10]ordmC respectively See how spin stabilized and 3 axes stabilized satellites look like in the [Annex89] Satellites are evolving

to either larger sizes to accommodate data processing capability and to smaller sizes some of them the size of a fist cube I have read about letter

stamp size like that would barely pick up signals and send them back to Earth Satellites are refining beam shaping increasing the amount of beams

sometimes no longer needing to deploy a parabolic reflector or any reflector

at all Main characteristics of FSAT LEO N LEO SAT1 (=Teledesic) MEO JKV and NGSO-KX satellite systems in

Antennnas -150 +80

Electronic equipment -30 +50

Solar panels power generator -160 +55

Battery -30 +25

Propellant Reservoir +10 +55

on-board thrusters or pyrotechnic unit

-170 +55

[annex10] Payload main characteristics include Satellite

mass (primary design parameter to decide as earlier as

possible during the design process) Primary power [W] RF power [W] eclipse operational and operational time

span or design life Make sure the client signs down agreeing on anything proposed or there is no point about

moving a single finger until budget secured in the shape of Memorandums of Understanding Contractual clauses and all

the legal paperwork that must precede any engineering

effort of this caliber Also in the annexes satellite specific payload main characteristics (SBS(F3) ANIK-C

SATECOM-V ARABSAT TELECOM-I EUTELSAT-II(ECS)IIVVII) [Annex11]

Lets focus on the transponder configuration for instance

that from a Koreasat transponder block diagram satellite [Annex12] South Korea indeed Transponders are

either transparent (repeater or bent-pipe) or with switchboard functions Time Space exchange

demodulating and modulating signals decoding and coding

Bit level recovery capacity cleaning the signal and

showing very low equivalent Noise Figures without having to leave unused large Back Off margins to

prevent intermodulation products

Anik-E main body tear down (TELESAT)

Yet a couple more transponders 1 Morelos payload block diagram [Annex13] satellite communications subsystem

(Hughes Space and Communications group) and 2 bent-pipe ANIK-E (TELESAT Canada) transponder [Annex14] in the

annexes so we can compare different lay outs for same functionality The antenna arrays may have horns aiming directly on Earth without reflector synthesizing beams with Radar processing

techniques I have found an INTELSAT antennas subsystem [Annex15] with reflectors for LNB and PA arrays 90ordm there

are better ways to avoid coupling The schematic just under top right corner 10m 14-11GHz reflector side view is the RF

splitter-combiner available on board to route received signals down on earth again Such RF commuters are mainly

mechanical devices and it takes seconds for the array to re-arrange paths All the contrary to modern solid state switch-over

routing that VLSI implemented they only work on low voltage low power signals allowing high data processing rates leaving RF muscle to embedded-on-chassis RF systems

42- Hubs Ground Stations

On the left Example of generic large Ground

station lay out with 3 antennas from ITU handbook for satellite communications Up

Menwith Hill satellite hub Radomes have to stand bad weather and at the same time they have

to be transparent throughout the radio band of

use According to an internet web site this ground station is used by Echelon But to be honest

nowadays if the customer pays for the service and data provided as long as it is legal does it really

matter Also in the annexes 1- general Earth station (segment 2) block diagram [Annex16]

and 2- Earth station Intelsat types A B D F1

F2 AND F3 parameters [Annex17] Major satellite hubs may be merged with optical fiber nodes

wired telephonybroadband exchange large stations John Bofarull Guix 12028225 jbb0025mylondmetacuk jgb2012skycom 4 8

and ground microwave link stations to save costs Such stations may require electrical High Voltage to Low Voltage

conditioning (that includes a bulky and expensive transformer among other parts) if the nearest electrical power line only happens to be HV Some of these stations include doubled power lines and one autonomous on-site that is tested regularly

like I have tested telephone exchange station batteries acid levels tests among many different regular procedures Common ACDC Power supply distribution block diagram [Annex18]

43- Hubs Control MAC

The main parameters that control stations monitor are Antenna Command status Receivers status Transmitters status Power status Building Integrity with test points on RF IF and BB Control stations must keep printed record of monitoring

ITU requires the MAC functionalities the same way that a chip designer configures a microprocessor pin-out configuration to satisfy desired functionality see ITU basic MAC segment requirements [Annex23] in annexes with in some stations a

single operator being able to look up any of monitored parameters on a pilot cockpit-like monitoring desk

44- MobileFixed Subscriber Equipment

Satellite MobileFixed subscriber equipment systems range from fixedembarkedhandheldembedded beacons that either

relay back regular information like sea conditions weather parameters or they receive only SMS like commands to control machinery or halffull duplex data transmission to accommodating one way HDTV orand broadband internet Some

equipment Iridium 9501 pager 9575 IsatPhone FleetBroadband500 Simplex GSP-1700 Thurayas products DM7020 HD

Amiko Comag HD25HDTV ComagSL40HD SK80FRHD kit Satwest for aircrafts AFFSpiderS3 SkyNodeS200 BGAN Hughes HNS9202 Thrane Explorer700 Comment on Iridium 9575 Extreme sat phone total recall [ID]

SOME BUILDING BLOCKS I have gathered some satellite communications system building blocks that (some of them)

have gone from hardware only to software designs Here I would have liked to develop a SIMULINK model and I would have

found out how well a bistatic radar with DVB-TT2 transmitters illuminating and satellites detecting would work that was the initial proposal for case study [RAD] But that would be a more an at least 6 months project than a 4 weeks case study Some

of the compiled blocks in annexes 1920 and 22

5- SERVICES back to contents

Here I am going to briefly comment some of the services that communication satellites currently offer Mobile Satellite

Technologies started offering telemetry (Sputnik transmitted a single tone that through calculated Doppler deviation was supposed to aid Soviet Submarines navigation It did so but only for few months as gravity brought it down sooner than

expected probably residual atmosphere had not been taken into account GOCE [Annex3] shows design improvement on this regard Sputnik didnt have fins behaving as short wings to take advantage of such drag [Annex43] Some satellites have

gotten closer to Earth surface in order to

1- Reduced delay Signals fromto a satellite at 35700km above surface experience at 19GHz(m) a delay of 0238sec

(including delay trip up+ delay trip down) FSL = sq((4R))= -18907dB If the orbit gets closer lets say 1500km

above Earth surface then FSL is reduced to -1615dB a message up and down only takes 10s We go from annoying

audio echoing to being able to keep pace with TTL gates pumping current or shutting down transistors on electronic boards and now same embarked receiver is receiving ~1000 times higher signal levels on both ground and embarked

RF front ends the only thing is that satellite chains are necessary with SLI (microwave orand optical SLI a couple

block diagrams in annexes) with real time hand-shake and hand-off to keep coverage on stationary subscribers 2- Increased spatial accuracy as it is shown in the NOAA SAR scenario [Annex262] LEO can sweep strips of ground

that all together configure accurate maps

Digital TV One of the problems with analog wireless communications requiring high power amplification is that they require

large TWT Back Off margins to avoid excessive RF intermodulation while digital transponders conveniently work on saturation getting the most out of the up sent radio power On the ground DVB-TT2 Single Frequency Networks

uses GPS to sync transmitters in SFN mode to transmit OFDM symbols at exactly the same time Because transmitters are scattered in a way that the delay from any transmitter to any receiver is no longer than a predefined Guard

Interval a known fraction of the OFDM symbol length it produces coherent reception (constructive symbol reception) where receivers deliberately ignore whatever happens on the symbol tails GI The Vertical Horizontal

polarizations isolation and frequency minimum spacing are design parameters that have become less stringent

when working with digital wireless channels There are still intermodulation limitations within digital modulations but the equivalent coding gain along with regenerative capability including capacity to change data rates also being able

to switch frequency and time channels render analog wireless channels less efficient compared to digital wireless Something else is that for instance some satellite and ground microwave FM links in the past widely used in ground and

satellite communications will be around until amortization of the investment is accomplished probably choosing COFDM

technology to upgrade the ground microwave link I recall jamming 15th of an 8MHz UHF DVB-T channel back in 1999 or overlapping an analog PAL signal exactly on same DVB-T signal UHF channel PAL carrier peak ~11dB above flat

noise-like DVB-T signal within same UHF channel and both analog PAL and the DVB-T were both perfectly received not

even switching hierarchy an option that allows DVB-T signal under heavy impairment to trade off data compression reducing signal quality BER reducing the amount of used carriers to only those still being received DVB-T was so

robust that it has allowed room to DVB-T2 again trading off initial data robustness for more broadband available within

same UHF channel bandwidth DVB-S2 transmission block diagram [Annex36] Comment on Multiple access efficiency [TDMA]

Interactive services DVB-RCC (DVB-S with Cable TV network interaction as return channel to collect subscriber uplink

queries) DVB-RCG DVB-RCGPRS (same but uplinking through GSM and GPRS respectively) DVB-RCSRCS2 (2 way satellite)

In April 2008 ICO along with Lucent-Alcatel and Expway launched 1st DVB-SH satellite ICO G1 And EUTELSAT W2A carries Solaris Mobile communications payload DVB-SH S band for Europe

Ground emergency wireless system GWEN Ground Wave Emergency Network 150 and 175MHz replaced by satellite

communications in 1999 GWEN was designed to survive and continue operation after nuclear attack

Satellite Optical communications I havent found much probably because there is where the money is hidden Superior

beam narrowness and much higher frequencies and therefore available bandwidth get Optical ahead of radio in areas like telemetry and ranging or even communications where Path Attenuation and worst case fading are not excessive

ruining the availability There have to be enough photons returning to the satellite or getting to the bi-static optical receiver in order to be detected Optical Surveillance Space Technologies AMOS (technical papers available online)

GPS Galileo GLONASS and Beidou (GEO in 2003 China also invested directly on Galileo and I have read

about their balloon communications satellite

I reproduce GSA forecasts because not even

themselves (GSA) think they may one day overtake wireless communications in market volume GPS

deployment for civilians was a change in habits for instance for vehicle drivers fleet controllers and

ground surveying Having an Ordnance local chart

handy is always useful but with GPS the traditional triangulation with optical devices to take accurate

positioning measurements has been relegated to measuring short distances like building construction

and urban

compliance double checking In the majority of situations there is no more need to interrogate drivers or pilots if the

vehicle GPS and a telemetry channel reporting location on real time Initially US DoD implemented a deliberate

interference that increased uncertainty to 300ft balls approx but civvies found ways round like scattering static stations that would report their exact location to be used by Differential GPS receivers Mentioning GPS is just one of many

quantum leaps that satellite communications mean to human kind

Some Specific products Example of what Satellite communications companies offer Internet over Satellite from for

instance Hughes Networks Transportable TCS-Swiftlink (transportable may be embarked but not hand held) L3-GCS Panther X-band VSAT Cheetah GD SATCOM Warrior Terminals DataPath On-the-move GSA Satellite Services-II

(SATCOM-II) contract for US government V-SAT (broadband high availability and back-up GVF Global V-SAT Forum) offering same IT capabilities as wired connections like P2P mesh connections (SCPC) and offering enough reliability

to secure contractor demands like Continuity of Operations (COOP) that is minimum thresholds on reliability and availability Government contracts impose terms like IDIQ Indefinite Delivery Indefinite Quantity Rewording whoever

awarded these kind of contracts have to be ready to stand long term demand and be able to deliver any quantity Any

one knows that sooner or later the engineering department will have to find ways round to such demands but on the other hand high expectations allow for high prices to be asked to clients Cannot be that expensive if Amateur radio gets

the hang of it with OSCAR satellites There are 3 satellite major operators offering global mobile communications service Inmarsat (3xGEO alt 22000mi)

Iridium (66xLEO alt 485mi)[Annex37] and Globalstar Then as example of regional operators offering regional mobile

communications throughout the Americas LightSquared TerreStar (Hughes) DBSD (the use of the word regional is in my opinion a bit bit awkward here as they refer to an area from Anchorage to the Patagonia prairies Personal Communications

(PCS) over satellite GMPCDS

ICO (Intermediate Circular Orbit) now Pendrell (Reters July 2011l) and Terrestar S band orbital slot 111ordm W Genus-1

blackberry like mobile phone hand set combining ATampT and satellite coverage North America only) deploying MSS (Mobile Satellite Service) networks related to ATC (Ancillary Terrestrial Components) 22GHz It is called satellite mobile

coverage with ancillary terrestrial component (coverage) John Bofarull Guix 12028225 jbb0025mylondmetacuk jgb2012skycom 5 8

INMARSAT F1 went global (TMcNet 2009) completing broadband deployment through repositioning programme without

service brownblack-outs 2009 I4 Americas (98ordmW) I4 EMEA (25ordmE) ASIA-PAC(1435ordmE) I found the Inmarsat online

ship contact webpage

BGAN Broadband Global Area Network Voice M2M XpressLink (monthly fee chosen by for instance FrontLine maritime oil crude transport company solution combines L-band and Ku V-SAT upgrade possible to 50Mbps Ka

GlobalExpress) and GMDSS Global Maritime Distress and Safety System

6- SATELLITE COMMUNICATIONS EXAMPLES back to contents

61- SKYBRIDGE 80 satellites (72ordmN 72ordmS) in Walker configuration 802015 (meaning 15 satellitesplane and

next satellite on sky is 67ordm vertical 15ordm horizontal apart) offering variable 60Mbps bandwidth to covered areas on fixed

Earth grid 3000kmcell Ground receivers need dishes between 03 and 1m

that is scanned by a network of advanced LEO satellites with onboard demodmod regeneration capacity (no bent-pipe

repeater therefore not subject to BO margins to avoid IP) and Inter Satellite Link communications to hand over open channels seamlessly in same way that ground wireless stations hand off moving users changing cells Here the base stations

are the moving parts while the subscribers are relatively steady from the satellites points of view

Tx EIRP[dBW] C[dBW]

Service Link forward

satellite user

21 dBW over 226MHz 64

Service Link return

satellite to gateway

79 dBW over 293MHz -71

Infrastructure Link satellite to gateway

214dBW over 226MHz 64

62- VSAT EQUIPMENT DESIGN START PARAMETERS

Uplink Space Downlink

Frequency 145GHz Satellite Location 70E frequency 12GHz

EIRP 55dB elevation 5deg Fade margin 5dB

Fade margin 6dB GT 0dBK CNo 69dBHz

CNo 70dBHz EIRP 20Dbw GT_vsat 20dBK

Access TDMA CN_IP 70dB 15m

Modulation QPSK transponder transparent EbNo (BERlt1E-7) 65dB

VSAT antennas have large side lobes compared to large dishes A Ku 1411 configuration means uplink 14GHz

downlink 11GHz And Ka 3020 means 30GHz uplink 20GHz downlink More V-SAT details in the annexes

63- GOCE [Annex3] is a modern LEO example equipped with ion thruster It also has fins to generate some lift

and counter residual atmosphere drag photos in annexes section

64- COSPAS-SARSAT distress locator service detecting beacons transmitting [4060 4061]MHz (1215243 MHz

stopped in 2009 406MHz band allows sending short messages) Ship beacons are EPIRB aircraft beacons are ELT and personal locators are PLB LEOSAR and GEOSAR are combined Distress alerts are relayed back to LEOLUT and

GEOLUT ground 20 fixed stations scattered throughout the world

65- ORBCOMM (1993) satellite system [Annex24] from Orbital Orbcom scenario depicted in the annexes

66- SAR example NOAA One of the problems early mono-static RADAR systems had and some around still suffer

from related clutter is that targets and terrain may shadow other targets Sometimes a known target might be disregarded because the illumination from a particular side returns a poor cross section therefore the operator would

ignore it Synthetic Aperture Radar aims at reconstructing targets by coherently adding different signals from different

angles that come from same target Even then there may be shadow areas left behind but LEO SAR satellites sweep Earth surface and each strip is scanned from different angles allowing partial or total reconstruction of terrain

surface NOAA is a SAR system belonging to the Canadian Space agency [Annex263]

7 WHERE ARE THE BIRDS back to contents

US Space Objects Registry CelestTrack LyngSat Orbitssera I have found 3 different formats NASA TLE OLE and AMSAT I include copy of explanation TLE and explanation for Keplerian elements orbit object coding in the annexes section just in

case it may be a good start point to write a program that reads such data Americom satellites position

NASA TLE Two Line Element (TLE) orbit element descriptor protocol was developed by NASA and the One Line Element (OLE) belongs to the US Navy

8 REGULATORS back to contents

It is not whether satellites have enough power to reach any spot on Earth but to make sure they do not fry things and

people Exposure to non-ionizing radiation longer than certain safety spans may be dangerous to body tissues Maximum RF

Transmission levels CCIR rec 524 I havent found yet same limitations for open air optical beams except civilian authorities banning the use of hand held laser pointers on the vicinity of airports to prevent reported temporary blindness of

pilots on few cases as if some people had nothing better to do than aiming at aircrafts with off-the-shelf hand held laser pointers I searched and it is true that some people living nearby airports where fined on this regard

The referenced Handbook has at the end an extensive list of ITU regulations on Satellite Communications the ones more

often used Antenna Pattern of Earth Stations CCIR recs 465 and 580 Maximum Transmission levels CCIR

rec358 Orbital position station keeping and antenna pointing requirements tolerances (for Geostationary) Radio

Regulations article 29 Permissive levels of interference from other networks CCIR recs466867523483

I also found link budget calculations guidelines so the regulator makes it clear how link budgets have to be done For

instance that Noise power (in Satellite Communications) from interference cannot be larger than 20 overall noise power Regenerative transponders and uncorrelated noise allow BER_total ~ BER_uplink + BER_downlink

In the UK OFCOM has recently accomplished the analog to digital TV transition (now DVB-TT2 phased switch-over) but

while satellite broadcast is widely used in the UK internet access over satellite is not seen as a preferred option as the report shows In previous OFCOM report after a lengthy evaluation of a bulky prototype head end (kind of grab that LNB that is

supposed to be attached to huge reflector and put it) on tripod aiming at a satellite from inside a comfortable room I quote research has to be done here meaning that OFCOM has to do some (more) research (regarding internet access over satellite) In between lines I also read invisible ink we (OFCOM) are going to do it but we are busy some where else right now

I put it this way to highlight how little interest Europe has to divert investment time and research away from wired and

ground wireless access networks My reasoning is we are NATO members but instead of trusting US satellites we try to wire as much as possible and we do not let internet over satellite US products in our markets but we export as many BMW and

Audi cars as we can to the US

In the OFCOM report there is also an odd reference to problems caused by rain attenuation again my guess the OFCOM

manager gave this project to some one who gave it to some one else in ARQIVA who ended up ringing the University of Plymouth who in turn found a 1st year student to undertake the mundane laboring of research who didnt even bother

justifying the presented text

So as useful as it may be just out of a nationwide analog-to-digital TV broadcasting technology transition with DAB not quite achieving the market share that it was initially expected and the ongoing crisis the UK government sees wiring the

nation for broadband access along with 4G and 5G with clear priority ahead of anything else

Another above 10GHz sample report I have chosen OFCOM March 2007 points on the same direction 15m dish Even

back to 2007 with ADSL already everywhere do you know of anyone whod have had the mood and time to have a 15m

dish installed on hisher roof Because I dont

I have taken some notes from the referenced Handbook regarding how regulators want Satellite Communications Link Budgets carried out see [Annex34] Relations between CN CN0 CT and EbNo in [Annex35]

INTELSAT and EUTELSAT required BER for Satellite Internet Broadband and Satellite SMS services for businesses

[Annex352]


9 STRATEGIC SECTOR THAT INCLUDES BIG BROTHER back to contents

Communications interception (eavesdropping interfering denying service supplanting) is one of the most basic types of

communications widely exploited in spectrum warfare yet some of these areas are proving to be of capital importance in preventing crime even when not exactly lawfully performed by law enforcement

The evolution of Echelon is closely related to Satellite Communications development WWII accelerated the increasing

importance of controlling the electromagnetic spectrum as well as rocketry development technology that has eventually

taken over conventional artillery and is the only current type of vehicle able to motion in outer space where there is no Oxygen for conventional Turbo Jet engines As historic sample of such spectrum surveillance evolution it is well known the

WWII Royal Navy Telconia success severing North Atlantic underwater wired communications between Germany and the US during WWII forcing all real time communications traffic go wireless so that the allied forces could monitor any real time

message crossing the Atlantic

There is a large amount of online misleading references regarding Echelon As far as I understood Echelon is a joint control

segment mainly military for all wireless communications monitoring it is one of the interfaces (for wireless data acquisition) that feeds joint data processing pools that grounds all radar base station and satellite signals sharing the primary source

(Radar primary) to prevent surprise aggressions that might end up in WWIII

No government capable of launching satellites will at least consciously allow a lucrative and strategic sector to become a

potential threat because civilian greed has left the door wide open to attacks like cyber attacks intrusive surveillance foreign radar illumination unauthorized radio signals collection and a long collection of threats that ends up with

hostile aircraft intrusion and enemy missile attack with any harmful war head you may think of Such threats usually referred as Nuclear Bio Chemical attacks [XBV] may wipe out entire cities when 80 years ago during WWI hundreds of

artillery units had to pound for hours or days narrow strips of front lone before attempting to advance a few yards

10 FREQUENCY BANDS back to contents

Satellite communications frequencies and power levels are heavily regulated because like for ground TVradio broadcasting stations it is not whether satellites may or may not pick up signals of standard equipment within coverage area but to make

sure that satellite downlinks do not interfere ground equipment keeping power levels within safe levels to population

From the time I worked with TV (ground) transmitters ground antennas sooner or later generate shadow areas or Earth curvature weather interferences and other factor weaken further than expected transmitted signals Satellites overcome

many of these problems because they have direct LOS and the majority of the signal paths are straight lines across free space much of it vacuum depending on elevation except when near horizon low elevation links or noiseinterferences

nearby either sides of the link

In [Annex30] WARC92 main frequency band limits for Satellite to sea Satellite to air and Satellite to ground wireless traffic

The most popular Satellite Communications band per launch in 2012 was the Ku band From the ITU handbook a bit more detailed in [Annex301]

Low frequencies usually reach further than higher frequencies to the point that 50kHz may penetrate sea town to 200m Whats far more difficult is to generate underwater electromagnetic signals that reach further than a few hundred meters due

to low impedance Water offers far better acoustic transmission properties better than air and in fact there are acoustic systems that are capable of low data rate transmission and reception over hundreds of nautical miles using repeaters

Of capital importance is compliance with spectral masks like required by ETSI302307 (download is free just register)

amplitude and group delay masks [Annex31] Band C is mostly used for Earth stations to Satellites uplinks

11 CONCLUSIONS back to contents

I chose a sector overview to rather dive into a specific system or technology because I wanted to assess the possibility of the satellite communications reaching internet access market shares similar to current wireless and wired operators I also wanted

to learn about working satellite communication systems main parameters only If in essence only it resembles the early times of wired telephony when many different local operators would develop businesses for later on requiring robust

nationwide communications backbones to support core traffic

Conclusion 1 Software radio is the way Software radio is a concept coming from military platforms that with smart

enough processors and code along with right RF headers a single platform can virtually use any coding modulation or frequency channel Again I am oversimplifying but the developments that initially helped to embark a single platform on

military aircrafts a data processing platform that allows pilots to interface with any kind of wireless standard around that flexibility has ended up in mobile phones that can use GSM GPRS EDGE 3G and 4G all in the size of a pocket gadget If the

platform is smart enough as National Instruments Software is the instrument

Conclusion 2 rivals and partners at the same time Ground operators see satellite communications useful from a

service point of view but as a rival that may end up sizing market share

Conclusion 3 market saturation Deploying an alternative access technology where 3G already being upgraded to 4G where tablets are being kicked in like Japanese underground users are pushed in wagons on peak hour where many

subscribers already have 2 mobile phones or expeditionary marketing effort called 3D trying to make us watch TV with

coloured paper clown goggles arguing that they have captured 3D on a plane Saturated markets are prone to dishonest practices like regulators fining foreign products with most absurd excuses that regretfully regulators have the tools to turn

into laws and fines Market drag The European government has correctly spotted great potential on satellite communications but the US

satellite industry is already exploiting such potential (as sample SKYBRIDGE) Then if something as common as a well

accepted computer operative system a consumer product from Microsoft suffers a millionaire fine at hands of European authorities just because the program does not ask whether users want to use Internet Explorer from Microsoft or they want

to install another Internet browser then it is difficult to think how any working US satellite system will secure long market share without suffering puppet proxy attacks from local competitors additional unexpected costs patents piracy and

dishonest fines from Spanish inquisition minded regulators My father went to sell heavy clay processing machines to former Soviet Union clients He came back saying that the budget had to be doubled initial amount to design produce supply and

install products and the other half to bribe and secure contacts delivery and to make it safe for things and people to go as

planned and end up wherever expected [OG] Iridium initial bankruptcy yet the excellence of provided service that allowed 2nd chance is evidence that there is demand for

such service Europeans use puppet regulators kind of Spanish inquisition American Iridium competitors went for a financial torpedo in the shape of tampering human resources basics that let in incompetent managers who were granted far too much

power that ended up crashing the budget That delayed deploymentoperation but it eventually took off

If the people on the street could walk in shops and purchase hand held satellite equipment that could challenge current ground wireless offer at a competitive price ground wireless operators would overnight slash prices arguing something as odd

that rare earths prices have dropped suddenly and that would force the newcomer to either reduce prices to stay competitive reducing initial benefit so necessary for any product launch

So regulators and operators defend their respective markets in their zones of influence but satellite communications make

the world really small from data sharing point of view

Conclusion 4 satellites make good wireless base stations Despite previous conclusions technically speaking communications satellites are far better wireless base stations than radiating systems on ground masts larger coverage

areas see-it-all within cell (rays no longer cross several buildings and metal structures that suddenly reduce signal levels) Launching is expensive but ground wireless operators also need far many more base stations to cover equivalent area More

base stations means more power consumption more regular maintenance more to be spent on towers and backhauls

The safety zone of a radiating system is a rectangular shape right in front of the radiating system that must be kept clear to avoid tissue damage due to high electric field [Vm] levels Home equipment would require dishes to focus beam on satellite

but LEO chains may even be close enough pick up signals like ground base stations do after all 1r^2 means same attenuation takes place for 1st 10km than for next 100km Transmitting mobile equipment may need more power but not

much more than many would expect I have not had time to compare link budgets but now there is almost always clear path

between mobile equipment and satellite base stations so fading is probably far less than mobiles seeking nearest 3G base stations for soft hand-overs across buildings power lines vehicles and motors generating noise and many other relatively

close antennas interfering at random On the ground sooner or later signal rays keep crossing each other when connecting to satellites all antennas aim up


Conclusion 5 budget constraints favour satellite superiority Satellite communications improvements have led to cost

cuts like the scrapping of the outstanding RAF Nimrod the delay in producing UK advanced air carriers or the gradual reduction of VHF and lower radio bands like in 2006 regional Spanish authorities made a beach party and a political major

achievement out of the dismantling of Radio Liberty station [RL]

The star of last mile wired internet access the undisputed winner technology despite the coupling problems that arise when

too much current pumped in and out of such short local loops is the ADSL [DSL] But with up to 140000basic wireless channelssatellite wireless back in the 90s circuits per satellite with satellite chains offering round the clock coverage with

lower orbits that allow shorter latency than many busy internet servers with satellite-to-satellite channels that can

dynamically route traffic to any hub on Earth is difficult to see any other impediment than the current operators that use regulators and governments like puppets

Conclusion 6 superiority in modern warfare depends upon satellite services availability Product example BAE

Dagger (Janersquos) The Military are gradually approaching broadband access to the front line with programs that are expensive and from the soldier point of view the only true validation would be surviving combat but mass commitment of any resource

to front line is a disastrous strategy with such lethal weaponry around

Conclusion 7 Technological synergies generates business opportunities Satellite communications may greatly

benefit from broadly developing dual systems with satellite downlink data downloads and return channels with far less traffic over wired or ground wireless operators

Robust encryption and base stations within LOS of subscribers are two points preventing subscribers from eavesdropping other subscribers or detecting traffic presence alone a system limitation that along with power level limitations and

omnidirectional antennas has kept WiFi as close range access technology only Because in satellite systems all subscriber antennas have to point upwards the man-in-the-middle problem disappears a security problem here and there occasionally

reported not only in ground wireless communications but also in wired telephony Satellite base stations for mass internet access would be inherently more secure potentially allowing far faster and easier IP address traceability

OPEN LINES

I chose and overview to gain understanding of the sector Diving into specifics would be a project like the project module in the MSc Because this is not a project I close this case study with some open lines

Open line 1 comparing ground wireless link budgets to satellite link budgets It would help to compare different satellite-fixed ground equipment satellite-mobile ground equipment to 3G equivalent link budgets and from there to generate

a list minimum requirements like power antenna directivity available data rate and basic BER for different coding and modulation schemes

Open line 2 GPS service upgrade potential sending and receiving free SMS over software upgraded GPS

equipment GPS is the most extended navigation system on Earth It is the only product and service from the satellite

communications industry that enjoys comparable levels of popularity to trendy mobile phones tablets and laptops with wireless WiFiGSMGPRSEDGE3G4GWiMAX capabilities

It would be interesting to see if upgradingreprogramming current GPS receivers standard 64kbps channels can be

downloaded and used as 1 way downlink channel While GPS tutorials correctly allocate 1 segment to users many experts

consider that satellite network control (MAC) must remain completely sizing one of the segments for security purposes SKYBRIDGE is already offering internet access over satellite but it is a stranger in Europe However GPS has already

scattered millions of terminals worldwide and the P(Y) code (P code is 1025MHz 267 days long PRN code and Y is P encrypted) is being upgraded GPS receivers could be software upgraded a bit further adding a couple additional downlink

carriers that GPS receivers would be able to use to receive downlink internet traffic Selling another set top box or another

mobile phone that can access the internet over satellite would be far more complicated and costly from the marketing point of view (the market is already saturated) than somehow upgrading firmware and applications in already existing GPS

receivers to for instance download internet through GPS positioning channels while queries uplink could be down through ground wireless operators The terminals already have the hardware capability the processor is fast enough and the

ADCDAC filtering and other functions are software based while on same frequency channels May be more memory would be required may be the whole architecture would require additional buses to be included but the RF processing capacity is

already on the hands of the end customer

COMMENTS back to contents [DSL] ISDN has advantages over ADSL more robust to coupling but the operators are the ones to prevent subscribers

enjoying 2 pairs when they could do with 1 pair only ADSL already exploits the asymmetry of internet traffic allocating far less available bandwidth to uplink than downlink DVB-T has an upgrade that also uses wired and wireless secure channels to

uplink queries of online shopping of items that have been purchased while browsing product details downloaded through TV

channels ADSL routers need distance to nearest exchange station to be less than approximately 3mi (wired length not straight line distance) or any other short distance on same order of magnitude to avoid COFDM carriers of one subscriber

excessively overlapping other COFDM ending up in BER degradation due to Inter-Symbol Interference Subscriber pairs must be so tightly packed in trunks that excessive coupling is unavoidable above certain transmission reception levels Operators

do not want subscribers to watch TV over the internet without paying the cost of pumping current to keep data streaming on continuous mode There is a huge gap of electrical consumption in the local exchange stations whether exclusive analog

telephony traffic is supported very low consumption or when the majority of routers keep streaming round the clock

demanding exclusive circuits (back to circuit focused access thinking when it was abandoned years ago to think ATM and packet switching arguing it is more efficient from the operator point of view but subscribers like dedicated circuits)

[EC] I still havent found any evidence that proves that secret services (any) are impervious to temptations like using

communications for free or a bit further down the line injecting fake currency through privileged control on data storage and

communications Communication controllers may not tamper democratic election processes or that they may not cause trouble to foreign companies in competition against their national ones or influence bidders to large contracts The ultimate

and only effective regulation against any abuse is the market itself Governments are economical intruders from the business efficiency point of view (Milton Freeman Nobel price definition of government regulations) that for the sake of the common

greater goood healthampsafety security spectrum compatibility and so on But governments not tax paying businesses and

citizens turn out to be the financial black holes that are dragging down an economy that is producing more millionaires than ever This is not a crisis caused by plagues on crops bad weather ruining sea trade bubonic epidemic or war between

nations for resources border lines or religion This is the wealthy of all over the world agreeing to exert control over everything worth being controlled for the sake of avoiding another world wide war

20 VAT on food pound1 out of pound5 goes to Brussels where it disappears perhaps in the Hadron Collider or in Galileo satellites

redundant to perfectly working GPS or in the huge EU government building that the vast majority of Europeans will never see or in a stealth UAV I just read about a continental Europe only project that has excluded the UK as far as I know This is

money that is kept away from developments like internet over satellite communications Banks dont like governments that do not pay back their debt is different than banks dont like governments that do not have money to pay back their debt An example of first type was Joseph Stalin who after the Soviet revolution attracted massive investment into URSS just to cancel incurred debts short afterwards Banks dont like governments spending what

they dont have But Banks want governments to spend what they have Banks only lend amounts similar to available

borrower assets this way they make sure that if investment goes wrong they can recover lending by sizing loan compromised assets Markets dont like either government quangos using public money to gain market share against private companies that

only through hard work achieve their well deserved market share But there is no free market without free communications

[ID] May 2012 production restarted quoting from Explorerweb April 2012 mechanical problem external antenna can lead to reduced performance from Global Maritime Networks April 2012 either the terminal doesnrsquot recognize there is an external antenna plugged or there is an impedance mismatch that wastes power I say this because if coax open then it may radiate

90ordm instead of lsquofire endrsquo like only seeking satellites heating the head of the speaker if not increasing SAR (Specific Absorption Rate ICNIRP and for instance Nardarsquos ) to unhealthy levels why didnrsquot they otherwise send the replacement only without

asking customers to send back the whole terminal

Ironic the most skilled people in the world designing space crafts with amazing station-keeping accuracy advanced rocketry and the best of the best and the business gets a hit because of a damn as cheap as peanuts antenna connector

[JQ] When someone working for Mr Gates (Microsoft) drafted a plan to massively increase wireless broadband access

through satellite coverage using Russian launching capacity it is urban legend that the next thing that happened was Mr

Gates received a phone call from then US president Mr Clinton inviting him for golf and next thing we the tax payers knew on the News it was that such Microsoft outstanding plan was delayed and left on a shelf to catch dust at best

[JKEG] History of Warfare John Kegan Following trend started during WWI when around 90 troops were committed

to front line engagements suffering massacre after massacre scarring entire nations and yielding little results at high price Aircraft reconnaissance the precursor of air and space surveillance started as needed means to gain advantage without

having to bury thousands of souls per hour just to advance a few yards WWII showed an initial German commitment of 60

only something that initially surprised the allied forces specially the French who had strongly advocated commitment as many resources to front line as possible Ironically the same dense forests that Erwin Rommel used to cut French supplies

rolling through gaps on French lines it was the same place where the Wehrmach attempted last limited offensive that was desperately planned under the risky assumption that bad weather would prevent allied aircraft to tell what they were up to


[ML] Military are capacitive there must be a reason to change or improve something and even when the need for

improvement is clear they let the system endure to see if they can do without examples the 1st US Marine Division and 3rd US Infantry Division reports highlighted in Mr Langleys UK Army report mentions the limitations of then LOS wireless

communication systems and the need for more reliable and capable systems Civilian business cannot afford such approach even when we the civvies do everything right there are many market factors

to take into account back-off margins are of capital importance

[RL] dismantling by demolition with explosives to bring down the towers such is the obtuse attitude of some authorities

lobbied by communications operators that want to keep exclusive control over the spectrum through their regulating puppets Some time ago I worked erecting antennas and fitting radiating systems for mobile communications operators and it is only

my opinion but the aberration of blowing up such equipment with explosives should be considered a crime let alone that the parts could be used and relocated but they decided to sell it all as scrap metal

[OG] The ineptitude of the masses is the title of a book written by Ortega Gasset You may have best product cheapest affordable something no one in common sense would refuse No matter how good your product and services are with nosy

regulators acting as puppets of those producing less efficient more expensive products the German shepherd guardian will make sure that your product doesnt get in Not because sooner or later some one in the mass controlled by the guardian

may point out that your product is better and that they want to try it Because they are no free to choose they gave up their freedom to carry arms they gave up the tools that may prevent abuse and with that they gave away their freedom of choice

when buying products

[RAD] IET MIMO Radar tutorial WiMAX Signal Ambiguity Function Analysis for Passive Radar Application (Qing Wang

Yilong Lu Chunping Hou) Ship Detection with DVB-T Software Defined Passive Radar (ACapria MConti DPet MMartorella FBerizzi )

[TDMA] comparisons in the ITU handbook show that TDMA remains on the top when large amounts of satellite accesses required compared to FDMA With increasing DSP onboard capacity frequency multiplexing within used band FDMA is not as

efficient as using a single carrier spanning the whole available BW and then use TDMA among users sharing same uplink carrier Obviously TDMA superior means it until a given band capacity is reached then FDMA is unavoidable but basically

breaking down spectrum less than in analog communications pays off from the spectrum efficiency point of view

[TN] In Erlangs as per Tons of transported information VHF FM and UHF TV transmitters had more BW and shoved more

data per hour even one way only analog many times recorded contents only than early mobile communications

[XBV] besides the blast and mechanical destruction radioactive ionizing radiation of tissues takes effect andor contamination with hazardous chemical andor biological agents Sounds bad it potentially is and if keeping satellite

communications underdeveloped means securing this corner then so be it so seem to pray all security agencies so far so

good

REFERENCES

SOME WEB LINKS if you need any internet link not included in this short list just ask me by email (footer) and I will send you electronic copy of the main document that includes all links

Satellite Industry Association wwwsiaorg

European Satellite Association wwwesoanet

Satellite Glossary and resource for Satcoms wwwprmtcom

SatMagazine wwwsatmagazinecom

SatNews wwwsatnewscom

Directory of FSSampDBS communications satellites wwwlyngsatcom

Satellite operating frequencies and applications wwwcanadaconnectscabroadbandmain1113

www2e1x1com gtgt www3dafsccom

1K1QFK VLF bands wwwvlfitfrequencybandshtml

Douglas HF measurements wwwemcesdcom

HF propagation models wwwitsbldrdocgovelberthfhtml

HF noise wwwmrecorgpubsHighFrequencyNoise_InformationPage_05pdf

advantages of HF wwwcodancomauHFRadioWhyHFtabit305

Sat PR News httpwwwsatprnewscom

GizmoWatch 20 Modern Engineering marvels 320 Satellite related

LITERATURE

Ka band satellite communications High Impact Technology what Gerard Blodkdijk

Information and Communications for Development 2012 Maximizing Mobile wwwworldbankorgict2012

Satellite Communication Systems 5th ed Maral Bousquet [B]

Satellite Communications isbn 978-0-470-71458-4 Freeman [Fr]

Pan-STARRS Imaging Array System NKaiser WBrugett JMorgan

Satellite Technology and Services October 2011 presentation Sia 101

Principles of Modern Radar ndash V Dismount Detection WMelvin JScheer Zuebeyde Guerbuez Satellite Communication Systems 2nd ed McMillan isbn 0333-74722-4 M Richharia

Handbook on Satellite Communications JWiley 3rd ed isbn 0-471-22189-9 ITU

Satellite Communications 4th ed isbn0-07-146298-8 DRoddy

Satellite Communications Systems 3rd IEE isbn 0-85296-899 BG Evans

ANNEXES

1- Countries with launching capability Some National Autonomous Satellite Operators

Some UK satellite technology know-how transfers 2- Communications Satellites brief time line

3- GOCE

4- IRIDIUM System main parameters 5- Example of EIRP and GT minimum requirements for Intelsat VII

6- Outer Space recent imagery Titan moon from Huygens BBC 7- Satellite Industry global activity 2009

8- Spin stabilized satellite example

9- 3 axes stabilized satellite example 10- FSAT LEO N LEO SAT1 (=Teledesic) MEO JKV and NGSO-KX satellite systems main parameters

11- Satellite specific payload main characteristics 12- KOREASAT transponder block diagram

13- MORELOS payload block diagram 14- bent-pipe ANIK-E (Telesat Canada) transponder

15- INTELSAT (1982) antennas subsystem

16- General Earth station block diagram (segment 2) 17- Earth station Intelsat types A B D F1 F2 AND F3 parameters

18- Common ACDC Power supply distribution block diagram 192122- some building blocks Tone range measurement block diagram

20- Split cooling basic diagram and heat transport liquid temperature range

23- ITU basic MAC segment requirements 24- ORBCOMM SMS texting over satellite system

25- CERISE once deployed the rod among other functions helps keep attitude 26- Real availabilities and used MTTFs

262- Some 90s satellites with onboard processing capabilities 263- SAR NOAA

27- Coding parameters (Forward Error Correction) for INTELSAT EUTELSAT TVSAT INMARSAT

28- Main transmission parameters for INTELSATEUTELSAT TDMA 29- Types of Modulations used in Satellite Communications

30- WARC92 maritime Aeronautical and ground mobile downlink and uplink frequency bands 301- Most used Satellite Communications Frequency bands

31 ETSI302307 amplitude and group delay masks

32- Teledesic 33- SKYBRIDGE

34- ITU Satellite Communications link budget some notes from GSS Communications Handbook 35- Relations between CN CN0 CT and EbNo (ITU Handbook for Satellite Communications)

352- INTELSAT and EUTELSAT required BER for Satellite Internet Broadband and Satellite SMS businesses

36- DVB-S2 exciter block diagram 37- IRIDIUM Scenario orbit planes satellite station-keeping accuracy details

38- Some notes about Basic Satellite Mechanics 39- Solid propellant thrusters mounted on satellites

40- Liquid propellants table 41- Launch vehicles table

42- Solar wind basics

43- Atmosphere drag below 800kn altitude basics ___________________________________________________________________________________________________

1- Countries with Launching Capability [2] back to contents

Russia (1957) RKA Baikonur US (1958) NASA Houston France (1965) Japan (1970) JAXA China (1970) UK (1971)

UK Space agency HQ Swindon ESA EU(1979 Paris Noordwijk NL Frascati Darmstadt Madrid Kourou French Guayanne) ISRO India Space agency (1980) Israel (1988) Israel Space agency Iran (2005) Iranian space agency

(Same acronym for International Space Agency)

Some National Autonomous Satellite Operators AUSSAT Australia NAHUELSAT Argentina SBTS Brazil TELESAT Canada SRW CHINASAT 1 ASIASAT China TELECOM France INSAT India KOPERNIKUS Germany INSAT India

PALAPA Indonesia ITALSAT Italy N-STAR Japan KOREASAT (South) Korea HISPASAT Spain SATCOM(RCA) COMSTAR

(ATampT) WESTAR(Western Union) SBS GSTAR(GTE) USA MOLNYA STATSIONAR LOUTCH Russia There are many more broadcasters and wiredwireless operators that have their own hubs

UK satellite technology know-how transfers (Surrey Satellite SSTL) Pakistan 1985-98 BADR-1 South Africa 1989-

91 UoSAT-345 South Korea 1990-94 KITSat-12 Portugal 1993-94 PoSAT-1 Chile 1997-97 FASat-AlfaBravo Thailand

1995-98 Merlion payload Malaysia 1996-98 TiungSAT-1 China 1998-99 TSINGHUA-1

2- IEEE Spectrum Aug2011 communications satellites brief time line back to contents

3- GOCE Metro February 2009 Example very Low Earth Orbit Satellite GOCE A Similar photo available from BAE website

4- Iridium System main parameters

5- Example of EIRP and GT minimum requirements for Intelsat VII

6- Outer Space recent imagery Titan moon from Huygens BBC

7- Satellite Industry global activity 2009 from GVF

Space report 2010 Downloaded document read

8- spin stabilized satellite example 9- 3 axes stabilized satellite example

10- FSAT LEO N LEO SAT1 (=Teledesic) MEO JKV and NGSO-KX satellite systems main parameters

11- Satellite specific payload main characteristics

12- Koreasat transponder block diagram

13- Morelos payload block diagram

14- bent-pipe ANIK-E (Telesat Canada) transponder


16- General Earth station block diagram (segment 2)

17- Earth station Intelsat types A B D F1 F2 AND F3 parameters

18- Common ACDC Power supply distribution block diagram

Routinely checking batteries acid pH is part of maintenance

19- some building blocks Tone range measurement block diagram

20- some building blocks Split cooling basic diagram and heat transport liquid temperature range

21- some building blocks bent-pipe transponder Input multiplexer

22- some building blocks Ku downconverter

23- ITU basic MAC segment requirements

24- Orbcomm SMS texting over satellite system

25- CERISE once deployed the

rod among other functions helps

keep attitude

26- Real availabilities and used MTTFs

262- Some 90s satellites with onboard processing capabilities

263 SAR NOAA

27 Coding parameters (Forward Error Correction) for INTELSAT EUTELSAT TVSAT INMARSAT

28 Main transmission parameters for INTELSATEUTELSAT TDMA

29 Types of Modulations used in Satellite Communications

30 WARC92 maritime Aeronautical and ground mobile downlink and uplink frequency bands

301 Most used Satellite Communications Frequency bands


32- Teledesic some details each Teledesic satellite covers 1400kmcell being able to offer up to 125000 basic channels

+ 16 Gigalink terminal channels Each basic channel offers 16kbps To avoid weather attenuation the minimum elevation is

40ordm Scenario

33- SKYBRIDGE

34- ITU Satellite Communications link budget some notes from GSS Communications Handbook

(CN)_total^(-1)=(CN)_up^(-1)+ (CN)_down^(-1)+ (CN)_IP^(-1)+ (CN)_interf^(-1)

(N_total=N_up+N_down+N_IP+N_interferences IP Intermodulation Products)

CNR=CN[dBHz] SNR[dB]= f middot CNR CNo=EbNo+10 log(r[bps])

C_upN_up=EIRP_tx ndash FSL ndash L_mu + (GT)_rx ndash 10 log(k) ndash 10 log(BW) repeat for the other 3 CNRs C_downN_down CNR_IP CNR_interf FSL free space loss L_mu worst case conditions as [Fr] points out FSL and additional attenuations

being considerated like

Cross Polar Coupling (should be 25 to 30dB isolation usually) Adjacent Channel Interference Adjacent Transponder Interference and Interferences from terrestrial systems are not enough to have a link working complying with required

availability BER requirements it is what [H] calls worst case conditions and [Fr] calls the fading margin

Ta Antenna temperature is the equivalent temperature of a resistor producing same amount of noise Ta[K]=1(4pi)

int(02pi0pi G(thetaphi) T(thetaphi)) According to CCIR rec2904 Cassiopeia A Cygnus A Taurus A are some of the stars used for calibration On the other side T_Sun~10000[K]

35- Relations between CN CN0 CT and EbNo (ITU Handbook for Satellite Communications)

352- INTELSAT and EUTELSAT required BER for Satellite Internet Broadband and Satellite SMS services for businesses

36- DVB-S2 exciter block diagram

37- IRIDIUM Scenario

IRIDIUM orbit planes IRIDIUM satellite station-keeping accuracy details

38- Some notes about Basic Satellite Mechanics Only in this last point blue font does not mean hyperlink present but just equations that one time or another I would have liked to translate to MATLAB code embedding such code snippets in the

text in order to help automating calculations

CONSTANTS 1N=02248[ftlb]=1[kgms] R_Earth~6700km f=c c(vacuum)=310^8ms Earth Mass

M=597410^24[kg] Universal Gravitational Constant G=667210^-11 [Nm^2kg^2=m^3(kgs^2)]

Keplerrsquos constant =GM=3985810^14[m^3s^2] D[]equivd[]dt []equivd[]dx ẋ+d[]dy ŷ + d[]dzẑ

R_Earth = 637814km (Lecture 2 foil 71 (pg18)True North = MAGNETIC North)

Boltzman constant k= 137910^-23[WkHz]

LEO h [5001000]km T[16 18]h

MEO h[800012000]km T~6h(10000km)

GEO i=0 e=0 equator plane h =36870 T=24h Earth Orbital Period HEO (Molnya T~11h38min h~39152500km)

Notation = r = r Vector product with X (no wedge) U time rrsquo rrsquorsquo

Intelsat(3578643km~23h56min4sec) ICO (10255km48954h) Skybridge (1469km 71272h) Iridium (780km74624h)

Keplerrsquos 3 laws

In the Solar system each planet moves in a plane describing an ellipse with the Sun on one Focus

The vectors from the Sun to the planets sweep equal areas within equal times

T_1^2a_1^3=T_2^2a_2^3= constant Newton amended T^2=(4pi^2a^3)

Newton Motion laws

When no F on a system total momentum is constant p(i)= m v(i)=0

F=ma = mrrsquorsquo

action reaction

Newton Universal Gravitational law F=-GM1M2r^2 limit to 2 BODIES M1 M2 in free space then

from origin point of view F1=-GM1M2r1^2 F2=GM2M1r2^2 from one of the bodies ( ) ( ) ( ) = r = r rrsquorsquo=G(M1+M2)r^2 If M1=MgtgtM2=m satellite and equivGM rrsquorsquo=-r^2

To stay on orbit set v = rrsquo (r x v)rsquo=rrsquov + rvrsquo=0 (rrsquo x v=0)

r x rrsquorsquo=r x (lsquor^2) r x vrsquo = -r^2 x = 0

(r x v)rsquo=0 (r x v)=H constant = angular momentum per mass unit equivalent to P=mv

P points on direction of linear movement H points out right hand rule perpendicular to circular movement plane

H = rvsin()= r v_v = r^2 vrsquo = 2 Arsquo A= area swept per second

H including mass H=r x mv[Nms]

Orbit differential equation

(u=1r u also in some books) rrsquorsquo=H^2u^2 D2udv^2 solution u= C cos(-o)+H^2

r=p(1+ecos(-o))

Gravitational Potential U=-GMr=-r[ms] Attraction force per unit of mass Fm=U[ms^2]

F=mȓr^2=GM_Earthmȓr^2 D2r ȓ+ ȓr^2=0

Centripetal force F_in=mr^2=Gm1m2r^2

Centrifugal force F_out=mv^2 variation of radial velocity D2r

centripetal acceleration r(D)^2

applying Dr = drdD r=1 D==H(mr^2) d2d2+=m^2H^2 solved r=p(1+ecos(-o))[m] [BV] since cos(a)=cos(-a) r=p(1+ecos(o)) True Anomalyequiv o

p=(H^2(m^2)

e=oH^2(m^2)

=o e=roVo^2-1 e=0

eccentricity Vo trajectory

0 sqrt(ro) circle

lt1 ltsqrt(2ro) ellipse

=1 =sqrt(2ro) parabola

gt1 gtsqrt(2ro) hyperbola

ORBIT PERIOD stable orbit means no radial overall force on satellite F_in=F_out

circular orbit T=2pirv

eliptic orbit T=2pir^15^5

About Ellipses a^2=b^2+c^2 x^2a^2+y^2b^2=1 e=(a-b)(a+b) Area_Ellipse=piab a=p(1-e^2) b=a(1-

e^2)

apogee a(1+e) perigee a(1-e) eccentricity e=(a-b)(a+b)

Satellite energy Eo[Junit_mass]=Vo^22-r

Satellite velocity radic (

)

[ms] if circular orbit v=radic

ORBIT CONSTANTS

Average Angular Velocity =sqrt(a^3)

Mean anomaly [angle] M=(t-t_p)

Eccentric anomaly [angle] M=E-esin(E)

Radius from orbit centre ro=a-aecos(E)

True Anomaly o r0=a(1-e^2)(1+ecos(o))

SATELLITE COORDINATES ON ORBITAL PLANE (r_o o) (x_0y_0) at time t

right ascension of the ascending node

i inclination

perigee argument

t_p perigee time

e

a

numbering days 1365

Right Ascension (RA) Perigee Argument Orbit Inclination ascending node (where satellite trajectory crosses equatorial plane

and getting closer to Earth) descending node (equivalent when satellite trajectory crosses equatorial plane and departing

from Earth)

39- Solid propellant thrusters mounted on satellites

40- Liquid propellants table

41- Launch vehicles table


photons hit a satellite with energy E[J]=mp c it is called energy of photons impinging the satellite under solar pressure relativistic mass of photons with energy E

Solar pressure P=(mp c)A = 1A (Ec) = c A[m2] normal incidence

solar flux radiation [Wm2] can be directly measured At Earths orbit (1 AU)=1360Wm2 P =454E-6 [Nm2]

photons are either specularly reflected (Cs) diffusely reflected (Cd) or absorbed (Ca) Cs+Cd+Ca=1

the acceleration caused by solar pressure on satellite m ap=P(1+Cs)Amsq(cos()) Sun declination Cd~0

in N revolutions a circular (e=0) GEO suffers e=15 apvt t = NT

This eccentricity correction is performed adding v=05vew to the Earth triaxiality drift correction (east-west station

keeping) not mentioned here

43- Atmosphere drag below 800kn altitude basics

=-05 Cd A v

D Drag force

Cd drag coefficient A cross section area

air density [kgm^3]

v satellite velocity vector

From literature adding drag to starting equations that end up in the basic orbit differential equation (in Annex38) the

ballistic coefficient is defined as B=CdA(2m) m satellite mass Assuming circular orbits now the differential equation to

solve is r = -2 B sqrt( G M r)

r=-4 pi B r^2 orbit radius decay per revolution

t=(sqrt(Re+ho)-sqrt(Re+h))(Bsqrt(GM) ) time that takes satellite to drop from ho to h (hltho) Re Earth radius

average within [hoh] =PM(RT) P gas pressure T[K] R=831434 J(kmol K) universal gas constant M molecular weight (O2 N2 )

within limited altitude range (regime) ~0 exp(-z) =Density Scale Height[km]

But to be really accurate on atmosphere drag additional factors have to be taken into account atmosphere expands and contracts following solar cycle

atmosphere latitude variations

atmosphere day-night variations

1 INTRODUCTION back to contents

Satellite Communications currently have the following 3 segments 1- Space 2- Ground and 3- Control When I think of

the Control segment I cannot avoid seeing it like the service elevator I used in Torrespantildea in one of my service visits bringing in VH602 amplifiers when some one hanged a faulty elevator note on the main elevator that directly reaches transmitters

level 7 floors between transmitters level and highest service lift level So it took me double effort to finish installation The service lift was of capital importance when the tower was being built but it was seldom used once the main lift was

operational

The Satellites Communications industry is attempting to go from the scenario on the left (from referenced literature) to the scenario on the right (I have replaced the control segment with USERS)

Such scenario modification is my attempt to highlight the importance that end subscribers must gain if Satellite Communications are going to get any internet-over-satellite significant market share in densely populated areas already

deeply penetrated by current ground wireless 3G4G and wired broadband access

Satellite communications are key part of the nuclear deterrent that in worst case would spot early ICBM launching allowing retaliation securing mutual destruction Because of the military importance of Satellite Communications the control segment

is factually a doubled network with the control segment holding right to eavesdrop and veto what we the civilians would call the main network Satellite Communications controllers have their own Satellite Communications channels the same way they

have their own airports and seaports bases The military do not have real interest in allowing mass satellite communications developing at least not in the same way that GSM started for instance They already allowed ARPANET to mutate to the

Internet why should they allow another spin-off that would only benefit civilians with real competition among operators The

traditional ground TV broadcast sector has also suffered from such regulatory attitude TV broadcasters used enough spectrum potential to offer same or even more broadband capacity compared to ground wireless communications but ground

broadcast industry never realized to see military mobile communications technological spin-offs take the stage along with most TV broadcasting spectrum eventually (DVB-T2 switch over) GSM 3G have centralized product development

investments there are many trendy mobile phone handsets with tablet and laptops incorporating wireless modems but

satellite mobile equipment still needs a small cumbersome dish or foldable cucumber-like antennas

Fierce enough is the competition among ground wireless and wired broadband operators so they remotely consider allowing yet another technology on what they consider their backyard the cellular market in densely populated areas Fierce but

wolves team up when intruder arrives Certainly there is increasing synergy like DVB hybrid networks and assisted GPS (A-GPS from Spirent) and some dual satellite mobile equipment able to directly route traffic to ground wireless base stations in

case of no coverage or better broadband service on the ground than over satellite But one thing is to use the GPS to relay

back position saving base stations to do so and the other one is to give up revenue

Satellite Communications are best or only choice at sea in desertedmountainous areas (oil rigs) and some rural and remote environments where it is too expensive to bring the copper pair to subscribers or there is poor or no ground wireless

coverage

The term Satellite Communications here refers to any wireless technology usage on satellite embarked platforms broad

sense including agreed full duplex channels for a video conference for instance down to the eavesdropping of mobile phone base stations and SIGINT telemetry sensors data relay broadband networking and imagery for instance
















































stations






















































































41- Space segment















Antennnas -150 +80



Battery -30 +25



-170 +55





























































































and urban






























Tx EIRP[dBW] C[dBW]


satellite user


Service Link return

























































[Annex352]















































































OPEN LINES






































































good

REFERENCES

















LITERATURE











ANNEXES



3- GOCE






























































keep attitude



263 SAR NOAA









40ordm Scenario

33- SKYBRIDGE























LEO h [5001000]km T[16 18]h

MEO h[800012000]km T~6h(10000km)




Keplerrsquos 3 laws




Newton Motion laws


F=ma = mrrsquorsquo

action reaction











r=p(1+ecos(-o))







p=(H^2(m^2)

e=oH^2(m^2)

=o e=roVo^2-1 e=0


0 sqrt(ro) circle








e^2)




)


ORBIT CONSTANTS








i inclination

perigee argument

t_p perigee time

e

a

numbering days 1365



from Earth)














=-05 Cd A v

D Drag force


air density [kgm^3]



























































stations






















































































41- Space segment















Antennnas -150 +80



Battery -30 +25



-170 +55





























































































and urban






























Tx EIRP[dBW] C[dBW]


satellite user


Service Link return

























































[Annex352]















































































OPEN LINES






































































good

REFERENCES

















LITERATURE











ANNEXES



3- GOCE






























































keep attitude



263 SAR NOAA









40ordm Scenario

33- SKYBRIDGE























LEO h [5001000]km T[16 18]h

MEO h[800012000]km T~6h(10000km)




Keplerrsquos 3 laws




Newton Motion laws


F=ma = mrrsquorsquo

action reaction











r=p(1+ecos(-o))







p=(H^2(m^2)

e=oH^2(m^2)

=o e=roVo^2-1 e=0


0 sqrt(ro) circle








e^2)




)


ORBIT CONSTANTS








i inclination

perigee argument

t_p perigee time

e

a

numbering days 1365



from Earth)














=-05 Cd A v

D Drag force


air density [kgm^3]







































































41- Space segment















Antennnas -150 +80



Battery -30 +25



-170 +55





























































































and urban






























Tx EIRP[dBW] C[dBW]


satellite user


Service Link return

























































[Annex352]















































































OPEN LINES






































































good

REFERENCES

















LITERATURE











ANNEXES



3- GOCE






























































keep attitude



263 SAR NOAA









40ordm Scenario

33- SKYBRIDGE























LEO h [5001000]km T[16 18]h

MEO h[800012000]km T~6h(10000km)




Keplerrsquos 3 laws




Newton Motion laws


F=ma = mrrsquorsquo

action reaction











r=p(1+ecos(-o))







p=(H^2(m^2)

e=oH^2(m^2)

=o e=roVo^2-1 e=0


0 sqrt(ro) circle








e^2)




)


ORBIT CONSTANTS








i inclination

perigee argument

t_p perigee time

e

a

numbering days 1365



from Earth)














=-05 Cd A v

D Drag force


air density [kgm^3]








































































































and urban






























Tx EIRP[dBW] C[dBW]


satellite user


Service Link return

























































[Annex352]















































































OPEN LINES






































































good

REFERENCES

















LITERATURE











ANNEXES



3- GOCE






























































keep attitude



263 SAR NOAA









40ordm Scenario

33- SKYBRIDGE























LEO h [5001000]km T[16 18]h

MEO h[800012000]km T~6h(10000km)




Keplerrsquos 3 laws




Newton Motion laws


F=ma = mrrsquorsquo

action reaction











r=p(1+ecos(-o))







p=(H^2(m^2)

e=oH^2(m^2)

=o e=roVo^2-1 e=0


0 sqrt(ro) circle








e^2)




)


ORBIT CONSTANTS








i inclination

perigee argument

t_p perigee time

e

a

numbering days 1365



from Earth)














=-05 Cd A v

D Drag force


air density [kgm^3]
























Tx EIRP[dBW] C[dBW]


satellite user


Service Link return

























































[Annex352]















































































OPEN LINES






































































good

REFERENCES

















LITERATURE











ANNEXES



3- GOCE






























































keep attitude



263 SAR NOAA









40ordm Scenario

33- SKYBRIDGE























LEO h [5001000]km T[16 18]h

MEO h[800012000]km T~6h(10000km)




Keplerrsquos 3 laws




Newton Motion laws


F=ma = mrrsquorsquo

action reaction











r=p(1+ecos(-o))







p=(H^2(m^2)

e=oH^2(m^2)

=o e=roVo^2-1 e=0


0 sqrt(ro) circle








e^2)




)


ORBIT CONSTANTS








i inclination

perigee argument

t_p perigee time

e

a

numbering days 1365



from Earth)














=-05 Cd A v

D Drag force


air density [kgm^3]











































[Annex352]















































































OPEN LINES






































































good

REFERENCES

















LITERATURE











ANNEXES



3- GOCE






























































keep attitude



263 SAR NOAA









40ordm Scenario

33- SKYBRIDGE























LEO h [5001000]km T[16 18]h

MEO h[800012000]km T~6h(10000km)




Keplerrsquos 3 laws




Newton Motion laws


F=ma = mrrsquorsquo

action reaction











r=p(1+ecos(-o))







p=(H^2(m^2)

e=oH^2(m^2)

=o e=roVo^2-1 e=0


0 sqrt(ro) circle








e^2)




)


ORBIT CONSTANTS








i inclination

perigee argument

t_p perigee time

e

a

numbering days 1365



from Earth)














=-05 Cd A v

D Drag force


air density [kgm^3]

























































































OPEN LINES






































































good

REFERENCES

















LITERATURE











ANNEXES



3- GOCE






























































keep attitude



263 SAR NOAA









40ordm Scenario

33- SKYBRIDGE























LEO h [5001000]km T[16 18]h

MEO h[800012000]km T~6h(10000km)




Keplerrsquos 3 laws




Newton Motion laws


F=ma = mrrsquorsquo

action reaction











r=p(1+ecos(-o))







p=(H^2(m^2)

e=oH^2(m^2)

=o e=roVo^2-1 e=0


0 sqrt(ro) circle








e^2)




)


ORBIT CONSTANTS








i inclination

perigee argument

t_p perigee time

e

a

numbering days 1365



from Earth)














=-05 Cd A v

D Drag force


air density [kgm^3]


































































good

REFERENCES

















LITERATURE











ANNEXES



3- GOCE






























































keep attitude



263 SAR NOAA









40ordm Scenario

33- SKYBRIDGE























LEO h [5001000]km T[16 18]h

MEO h[800012000]km T~6h(10000km)




Keplerrsquos 3 laws




Newton Motion laws


F=ma = mrrsquorsquo

action reaction











r=p(1+ecos(-o))







p=(H^2(m^2)

e=oH^2(m^2)

=o e=roVo^2-1 e=0


0 sqrt(ro) circle








e^2)




)


ORBIT CONSTANTS








i inclination

perigee argument

t_p perigee time

e

a

numbering days 1365



from Earth)














=-05 Cd A v

D Drag force


air density [kgm^3]












REFERENCES

















LITERATURE











ANNEXES



3- GOCE






























































keep attitude



263 SAR NOAA









40ordm Scenario

33- SKYBRIDGE























LEO h [5001000]km T[16 18]h

MEO h[800012000]km T~6h(10000km)




Keplerrsquos 3 laws




Newton Motion laws


F=ma = mrrsquorsquo

action reaction











r=p(1+ecos(-o))







p=(H^2(m^2)

e=oH^2(m^2)

=o e=roVo^2-1 e=0


0 sqrt(ro) circle








e^2)




)


ORBIT CONSTANTS








i inclination

perigee argument

t_p perigee time

e

a

numbering days 1365



from Earth)














=-05 Cd A v

D Drag force


air density [kgm^3]












ANNEXES



3- GOCE






























































keep attitude



263 SAR NOAA









40ordm Scenario

33- SKYBRIDGE























LEO h [5001000]km T[16 18]h

MEO h[800012000]km T~6h(10000km)




Keplerrsquos 3 laws




Newton Motion laws


F=ma = mrrsquorsquo

action reaction











r=p(1+ecos(-o))







p=(H^2(m^2)

e=oH^2(m^2)

=o e=roVo^2-1 e=0


0 sqrt(ro) circle








e^2)




)


ORBIT CONSTANTS








i inclination

perigee argument

t_p perigee time

e

a

numbering days 1365



from Earth)














=-05 Cd A v

D Drag force


air density [kgm^3]
















































keep attitude



263 SAR NOAA









40ordm Scenario

33- SKYBRIDGE























LEO h [5001000]km T[16 18]h

MEO h[800012000]km T~6h(10000km)




Keplerrsquos 3 laws




Newton Motion laws


F=ma = mrrsquorsquo

action reaction











r=p(1+ecos(-o))







p=(H^2(m^2)

e=oH^2(m^2)

=o e=roVo^2-1 e=0


0 sqrt(ro) circle








e^2)




)


ORBIT CONSTANTS








i inclination

perigee argument

t_p perigee time

e

a

numbering days 1365



from Earth)














=-05 Cd A v

D Drag force


air density [kgm^3]













263 SAR NOAA









40ordm Scenario

33- SKYBRIDGE























LEO h [5001000]km T[16 18]h

MEO h[800012000]km T~6h(10000km)




Keplerrsquos 3 laws




Newton Motion laws


F=ma = mrrsquorsquo

action reaction











r=p(1+ecos(-o))







p=(H^2(m^2)

e=oH^2(m^2)

=o e=roVo^2-1 e=0


0 sqrt(ro) circle








e^2)




)


ORBIT CONSTANTS








i inclination

perigee argument

t_p perigee time

e

a

numbering days 1365



from Earth)














=-05 Cd A v

D Drag force


air density [kgm^3]




















40ordm Scenario

33- SKYBRIDGE























LEO h [5001000]km T[16 18]h

MEO h[800012000]km T~6h(10000km)




Keplerrsquos 3 laws




Newton Motion laws


F=ma = mrrsquorsquo

action reaction











r=p(1+ecos(-o))







p=(H^2(m^2)

e=oH^2(m^2)

=o e=roVo^2-1 e=0


0 sqrt(ro) circle








e^2)




)


ORBIT CONSTANTS








i inclination

perigee argument

t_p perigee time

e

a

numbering days 1365



from Earth)














=-05 Cd A v

D Drag force


air density [kgm^3]


































LEO h [5001000]km T[16 18]h

MEO h[800012000]km T~6h(10000km)




Keplerrsquos 3 laws




Newton Motion laws


F=ma = mrrsquorsquo

action reaction











r=p(1+ecos(-o))







p=(H^2(m^2)

e=oH^2(m^2)

=o e=roVo^2-1 e=0


0 sqrt(ro) circle








e^2)




)


ORBIT CONSTANTS








i inclination

perigee argument

t_p perigee time

e

a

numbering days 1365



from Earth)














=-05 Cd A v

D Drag force


air density [kgm^3]














Newton Motion laws


F=ma = mrrsquorsquo

action reaction











r=p(1+ecos(-o))







p=(H^2(m^2)

e=oH^2(m^2)

=o e=roVo^2-1 e=0


0 sqrt(ro) circle








e^2)




)


ORBIT CONSTANTS








i inclination

perigee argument

t_p perigee time

e

a

numbering days 1365



from Earth)














=-05 Cd A v

D Drag force


air density [kgm^3]














i inclination

perigee argument

t_p perigee time

e

a

numbering days 1365



from Earth)














=-05 Cd A v

D Drag force


air density [kgm^3]























=-05 Cd A v

D Drag force


air density [kgm^3]












Satellite Communications Overview College assignment

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Transcript of Satellite Communications Overview College assignment