Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)

September 2003

Multi-band OFDM ProposalSlide 1

doc.: IEEE 802.15-03/343r0

Submission

Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)

Submission Title: [Multi-band OFDM Physical Layer Proposal Response to no Voters]Date Submitted: [14 September 2003]Source: [Presenter: see page 2 for the complete list of participating authors and their companies]

Re: [This submission is in response to the IEEE P802.15 Alternate PHY Call for Proposal (doc. 02/372r8) that was issued on January 17, 2003.]

Abstract: [This document gives modifications and more details for Multi-band OFDM proposal for IEEE 802.15 TG3a (doc.03/267/r2).]

Purpose: [To address the concerns raised by the no voters in the July03 meeting]

Notice: This document has been prepared to assist the IEEE P802.15. It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein.Release: The contributor acknowledges and accepts that this contribution becomes the property of IEEE and may be made publicly available by P802.15.

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Submission

This contribution is authored by :

Alereon - Vern Brethour, Martin Gravenstein, Joy Kelly, Tom Matheney, Kevin Shelby General Atomics, Photonics Division - Naiel Askar, Susan LinIntel Corporation - Chuck Brabenac, Jeff Foerster, Dave Leeper, Srinivasa Somayazulu, Stephen Wood Mitsubishi Electric - Andy Molisch, Yves-Paul Nakache, Jin ZhangPhilips - Charles RazzellSamsung Electronics - Seung Young Park, Yongsuk KimStaccato Communications - Roberto Aiello, Nishant Kumar, Lars Mucke, Torbjorn Larsson, Larry TaylorST Microelectronics - Ljubica Blazevic, Glyn Roberts Texas Instruments - Jai Balakrishnan, Anuj Batra, Anand Dabak, Srinivas LingamTDK – Robert SuttonUniversity of Minnesota - Ahmed Tewfik, Ebrahim Saberinia, Jun TangWisair - Gadi Shor

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Submission

The MB-OFDM proposal is a technical merger between*:Texas Instruments [03/141]: Batra

\

andfemto Devices [03/101]: CheahFOCUS Enhancements [03/103]: BoehlkeGeneral Atomics [03/105]: EllisInstitute for Infocomm Research [03/107]: ChinIntel [03/109]: BrabenacMitsubishi Electric [03/111]: MolischPanasonic [03/121]: MoPhilips [03/125]: KerrySamsung Advanced Institute of Technology [03/135]: KwonSamsung Electronics [03/133]: ParkSONY [03/137]: FujitaStaccato Communications [03/099]: AielloSTMicroelectronics [03/139]: RobertsTime Domain [03/143]: KellyUniversity of Minnesota [03/147]: TewfikWisair [03/151]: Shor

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Submission

MB-OFDM Proposal Authorsfemto Devices: J. CheahFOCUS Enhancements: K. Boehlke General Atomics: J. Ellis, N. Askar, S. Lin, D. Furuno, D. Peters, G. Rogerson, M. WalkerInstitute for Infocomm Research: F. Chin, Madhukumar, X. Peng, SivanandIntel: J. Foerster, V. Somayazulu, S. Roy, E. Green, K. Tinsley, C. Brabenac, D. Leeper, M. HoMitsubishi Electric: A. F. Molisch, Y.-P. Nakache, P. Orlik, J. ZhangPanasonic: S. MoPhilips: C. Razzell, D. Birru, B. Redman-White, S. KerrySamsung Advanced Institute of Technology: D. H. Kwon, Y. S. KimSamsung Electronics: M. ParkSONY: E. Fujita, K. Watanabe, K. Tanaka, M. Suzuki, S. Saito, J. Iwasaki, B. HuangStaccato Communications: R. Aiello, T. Larsson, D. Meacham, L. Mucke, N. Kumar STMicroelectronics: D. Hélal, P. Rouzet, R. Cattenoz, C. Cattaneo, L. Rouault, N. Rinaldi,, L.

Blazevic, C. Devaucelle, L. Smaïni, S. Chaillou Texas Instruments: A. Batra, J. Balakrishnan, A. Dabak, R. Gharpurey, J. Lin, P. Fontaine,

J.-M. Ho, S. Lee, M. Frechette, S. March, H. YamaguchiTime Domain: J. Kelly, M. PendergrassUniversity of Minnesota: A. H. Tewfik, E. SaberiniaWisair: G. Shor, Y. Knobel, D. Yaish, S. Goldenberg, A. Krause, E. Wineberger, R. Zack, B.

Blumer, Z. Rubin, D. Meshulam, A. Freund

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Submission

In addition, the following individuals/companies support the MB-OFDM proposal:

Fujitsu Microelectronics America, Inc: A. Agrawal Hewlett Packard: M. FidlerInfineon: Y. RashiJaalaa: A. Anandakumar Microsoft: A. HassanNEC Electronics: T. SaitoSVC Wireless: A. YangTDK: P. CarsonTRDA: M. TanahashiUWB Wireless: R. Caiming QuiWisme: N. Y. Lee

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Summary Multiband OFDM Proposal July – September Activities Proposal Summary FCC Regulation Issue Time to market IP statements Simultaneously operation piconets (SOP) performance Complexity and power consumption and scalability CCA MAC enhancements Symbol Definition Ranging and Location Conclusions Q&A (save your questions, reference foil number)

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How “NO” votes were addressed The Multi-band OFDM proposers analyzed the issues raised by

the no-voters from the July meeting. The issues were broken down into subgroups for technical and

business evaluation Each subgroup had participants from multiple companies

Held multiple meetings per week to discuss how best to address issues raised by no-voters and possible improvements

A number of options were evaluated and simulated

Summary of results and system improvements will be presented next

We are confident we have adequately addressed all the issues raised by the no-voters

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Submission

Summary of Multi-band OFDM System

Presenter: Anuj Batra (TI)

The complete Multi-band OFDM proposal can be found in the latest revision of the Word

document 03/268.

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Overview of Multi-band OFDM

Basic idea: divide spectrum into several 528 MHz bands.

Information is transmitted using OFDM modulation on each band. OFDM carriers are efficiently generated using an 128-point IFFT/FFT. Internal precision requirement is reduced by limiting the constellation size to

QPSK.

Information is coded across all bands in use to exploit frequency diversity and provide robustness against multi-path and interference.

60.6 ns prefix provides robustness against multi-path even in the worst channel environments.

9.5 ns guard interval provides sufficient time for switching between bands.

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Multi-band OFDM System Parameters

System parameters for mandatory and optional data rates:

Info. Data Rate 55 Mbps* 80 Mbps** 110 Mbps* 160 Mbps** 200 Mbps* 320 Mbps** 480 Mbps**

Modulation/Constellation OFDM/QPSK OFDM/QPSK OFDM/QPSK OFDM/QPSK OFDM/QPSK OFDM/QPSK OFDM/QPSK

FFT Size 128 128 128 128 128 128 128

Coding Rate (K=7) R = 11/32 R = 1/2 R = 11/32 R = 1/2 R = 5/8 R = 1/2 R = 3/4

Spreading Rate 4 4 2 2 2 1 1

Data Tones 100 100 100 100 100 100 100

Info. Length 242.4 ns 242.4 ns 242.4 ns 242.4 ns 242.4 ns 242.4 ns 242.4 ns

Cyclic Prefix 60.6 ns 60.6 ns 60.6 ns 60.6 ns 60.6 ns 60.6 ns 60.6 ns

Guard Interval 9.5 ns 9.5 ns 9.5 ns 9.5 ns 9.5 ns 9.5 ns 9.5 ns

Symbol Length 312.5 ns 312.5 ns 312.5 ns 312.5 ns 312.5 ns 312.5 ns 312.5 ns

Channel Bit Rate 640 Mbps 640 Mbps 640 Mbps 640 Mbps 640 Mbps 640 Mbps 640 Mbps

Multi-path Tolerance 60.6 ns 60.6 ns 60.6 ns 60.6 ns 60.6 ns 60.6 ns 60.6 ns

* Mandatory information data rate, ** Optional information data rate

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Band Plan (1)

Group the 528 MHz bands into 4 distinct groups.

Group A: Intended for 1st generation devices (3.1 – 4.9 GHz). Group B: Reserved for future use (4.9 – 6.0 GHz). Group C: Reserved for devices w/ improved SOP performance (6.0 – 8.1 GHz). Group D: Reserved for future use (8.1 – 10.6 GHz).

f3432MHz

3960MHz

4488MHz

5016MHz

5808MHz

6336MHz

6864MHz

7392MHz

7920MHz

8448MHz

8976MHz

9504MHz

10032MHz

Band#1

Band#2

Band#3

Band#4

Band#5

Band#6

Band#7

Band#8

Band#9

Band#10

Band#11

Band#12

Band#13

GROUP A GROUP B GROUP C GROUP D

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Multi-mode Multi-band OFDM Devices (1)

Having multiple groups of bands enables multiple modes of operations for multi-band OFDM devices.

Different modes for multi-band OFDM devices are:

Future expansion into groups B and D will enable an increase in the number of modes.

Mode Frequency of Operation Number of Bands Mandatory / Optional

1 Bands 1–3 (A) 3 Mandatory

2 Bands 1–3, 6–9 (A,C) 7 Optional

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Multi-mode Multi-band OFDM Devices (2)

Frequency of operation for a Mode 1 device:

Frequency of operation for a Mode 2 device:

f3432MHz

3960MHz

4488MHz

Band#1

Band#2

Band#3

f3432MHz

3960MHz

4488MHz

6336MHz

6864MHz

7392MHz

7920MHz

Band#1

Band#2

Band#3

Band#6

Band#7

Band#8

Band#9

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FCC Compliance of MB-OFDM

Presenter: Anand Dabak

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Background During the San Francisco IEEE meeting XSI made a presentation on FCC rules:

Slide 3 of 03153r9P802-15_TG3a-XtremeSpectrum-CFP-Presentation.ppt The issue today is NOT whether or not there is more or less interference The issue is, what are the rules.

Side interest is WHY did NTIA and FCC specifically write rules for frequency hoppers

Slide 5 from 03153r9P802-15_TG3a-XtremeSpectrum-CFP-Presentation.ppt;

XSI claimed that MB-OFDM needs to reduce its transmit power by 4.7 dB to be FCC compliant, MB-OFDM should transmit at -46 dBm/MHz (instead of -41.3 dBm/MHz)

3168 MHz

3696 MHz

4224 MHz

4752 MHz

Time

Band-3

Band-2

Band-1 Band-1

Band-2

Avg Pwr = 1/3 of “hopping-on” Power

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Background (2)

MB-OFDM alliance was asked to contact the FCC to clarify the rules.

XSI/Motorola further filed a petition with the FCC for declaratory ruling immediately after the San Francisco meeting.

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MB-OFDM Activities after S.F. to Address FCC Issues

MB-OFDM alliance contacted and met with the FCC/OET staff, among them Ed Thomas, Chief of the FCC’s Office of the Engineering and

Technology (OET) Julius Knapp, Deputy Chief of the OET John Reed, staff member of the OET

Two meetings and one phone call took place, on August 7th, 15th, and 23rd, 2003.

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Over the past few weeks several parties have met with the staff of the Federal Communications Commission Office of Engineering and Technology to discuss how the Commission’s rules for Ultrawideband devices might be applied for certain signal formats that are being considered by IEEE 802.15.

OET believes it is premature to make any determination as to the appropriate measurement methods for particular signals because this matter is under active discussion in IEEE. In this regard, we have no immediate plans to respond to the XSI/Motorola request for a declaratory ruling.

We urge that IEEE perform technical analyses to ensure that any UWB standard it develops will not cause levels of interference beyond that already anticipated by the rules.

This information will be needed to support any necessary FCC rules interpretations or other appropriate action for the chosen standard.

The FCC has had a long history of working cooperatively with the IEEE 802 committee in addressing any regulatory issues that may arise relative to standards. We recommend that IEEE proceed with its standards development process and that the committee address any questions to us at a later time when it has formed a specific proposal.

FCC’s response*

Summary of Discussions with FCC Staff Concerning IEEE 802.15 Deliberation On Standards for Ultrawideband devices

*:E-mail sent by Julius Knapp, Deputy Chief, OET, FCC to XSI/Motorola and MB-OFDM proponents on September 11th, 2003

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FCC’s response: Point 1

FCC does not wish to become a pawn in the IEEE standards process, nor do they wish to stimulate needless new public-comment processes.

FCC has no current plans to respond to the XSI/Motorola petition for declaratory ruling.

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FCC’s response*



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FCC’s response: Point 2 FCC recommends that IEEE proceed with its standards development

process and provide technical analyses for OET as needed to support any necessary FCC rules interpretations for the chosen standard.

FCC says that a proposed UWB approach would likely be deemed compliant if it could be shown that it would not cause levels of interference beyond that already anticipated by the rules.

Contrary to XSI claims that interference is not the issue, FCC told MB-OFDM group that interference from UWB to other systems is an important issue.

XSI claimed it is a “rules issue”

XSI claimed it is not an “interference issue”

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FCC’s response*



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FCC’s response: Point 3 FCC reminds IEEE that it has a long history of cooperation with IEEE

on rules interpretation and approvals for new technologies.

FCC recommends that IEEE proceed with its standards development process and select a UWB proposal.

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Summary of Presentation We analyzed several different interference scenarios from MB-OFDM to

other systems.

MB-OFDM does not cause any more interference than already anticipated by current FCC rules.

Hence, contrary to XSI’s claims we believe MB-OFDM is compliant and should not have to reduce its transmit power by 4.7 dB to be FCC compliant. All link budget calculations done by MB-OFDM group in 03267r1P802-15_TG3a-

Multi-band-OFDM-CFP-Presentation.ppt in San Francisco are correct.

Lab measurements for MB-OFDM signals based upon MB-OFDM prototype.

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MB-OFDM Interference Study

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UWB Interference Considerations History of FCC ruling on UWB

Detailed interference studies: Process took 4 years to decide with > 1,000 comments and several detailed technical studies Must include usage scenarios, realistic propagation losses, antenna patterns, etc.

Interference studies included considerations of both peak and average limits

Final FCC R&O based upon ‘ultra-conservative’ limits ‘far below’ those placed on technologies that place energy into narrower portions of the spectrum.’ [Separate Statement of Commissioner Michael J. Copps, February 14, 2002]

Large amount of data was examined by the FCC before FCC ruling

We all have a responsibility to ensure interference into other radio services does not cause harm (example GPS, cellular and others)

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FCC/NTIA Interference results for various US government systems

SystemFrequency

(MHz)

MaximumUWB EIRP(dBm/MHz)

UWBIndoors

2 m height

Maximum UWBEIRP

(dBm/MHz)UWB

Indoors30 m height

IF Bandwidth Margin from currentPart 15 limits

DME,Interrogator

960-1215

-38 Not Applicable1 650 KHz 37.3 dB

DME,Transponder

1025-1150

-55 -48 800 KHz 20.3 dB

ATCRBS,Transponder

1030 -35 Not Applicable 5.5 MHz 40.3 dB

ATCRBS,Interrogator

1090 -22 -35 9 MHz 40.3 dB

ARSR-4 1240-1370

-52 -73 690 KHz 2.3 dB

SARSAT 1544-1545

-60 -57 800 KHz 15.3 dB

ASR-9 2700-2900

-37 -57 653 KHz 14.3 dB (indoor)4.3 dB (outdoor)

NEXRAD 2700-2900

-33 -67 550 KHz 18.3 dB (indoor)

MarineRadar

2900-3100

-34 -45 4-20 MHz 17.3 dB (indoor)16.3 dB (outdoor)

FSS, 20degrees

3700-4200

-24 -30 40 MHz 17.3 dB (indoor)11.3 dB (outdoor)

1 “Not Applicable” indicates that the particular scenario would involve an airborne receiver at the same altitude as a UWB transmitter,which should not occur.

Most systems have substantial margin available

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FCC/NTIA Interference results for various US government systems

SystemFrequency

(MHz)

MaximumUWB EIRP(dBm/MHz)

UWBIndoors

2 m height

MaximumUWBEIRP

(dBm/MHz)UWB

Indoors30 m height

IF Bandwidth Margin fromcurrent Part 15

limits

FSS*, 5degrees

3700-4200

-39 -65 40 MHz 2.1 dB (indoor)

CWAltimeters

4200-4400

37 NotApplicable

N/A 78.3 dB

PulsedAltimeters

4200-4400

26 NotApplicable

30 MHz 67.3 dB

MLS 5030-5091

-42 NotApplicable

150 KHz -

TDWR 5600-5650

-23 -51 910 KHz 18.3 dB

Analysis based upon free-space propagation: even more conservative

*:DirecTV/EchoStar/DBS receivers do not operate in 3.7-4.2 GHz; they operate in the 11.7-12.2 GHz band

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UWB interference on Fixed Satellite Service (FSS) Receivers

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Average interference power is same

Objective is to compare MB-OFDM to impulse radios FCC analyzed impulse radios before issuing R&O Conservative R&O allows impulse radios

Following slides analyze UWB interference to FSS receivers FSS frequency of operation: 3.7-4.2GHz DirecTV/EchoStar/DBS receivers do not operate in 3.7-4.2 GHz; they operate

in the 11.7-12.2 GHz band

MB-OFDM transmitter’s power as described in MB-OFDM proposal

DSSS, MB-OFDM and impulse radios provide identical average interference power, Actual performance of FSS system depends on specific receiver

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UWB Waveforms for FSS Interference Analysis

DSSS

MB-OFDM

Impulseradio

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2-0.2

-0.1

0

0.1

0.2

Time(usec)

Am

plitu

de

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2-0.2

-0.1

0

0.1

0.2

Time(usec)

Am

plitu

de

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2-0.2

-0.1

0

0.1

0.2

Time(usec)

Am

plitu

de

Average interference power is identical

Victim receiver performance depends upon receiver characteristic: Modulation, coding, interleaving

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FSS interference evaluation parameters

– Victim receiver: Example FSS system parameters (implementation dependent) Parameter Values

Center Frequency 3.7-4.2 GHz, with and withoutf requency off set

Convolutional coding Rate ½, 7/ 8, k = 7

Reed Solomon coding (204, 188)

Symbol rates 35 MSPS

Modulation QPSK

Waveform Root raised cosine, alpha = 0.25

Target I / N values -6 dB, - 0.4 dB

UWB antenna height 2m

FSS antenna height* 3 m

FSS antenna angle 50, 200

*: NTIA special publication 01-43, Assessment of compatibility between ultra-wideband devices and selected federal systems

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Interfering Systems

– Interfering system (1): DS-SS UWB system White Gaussian noise interference

– Interfering system (2): MB-OFDM system characteristics Exactly as described in proposal

– Interfering system (3): Impulse UWB radio characteristic PRF >= 1 MHz

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3 4 5 6 7 8 910

-4

10-3

10-2

10-1

100

Interference comparison between various UWB waveforms

SINR

Bit

Err

or

Ra

te

White Gaussian Noise InterferenceMB-OFDM with 3 bandsMB-OFDM with 7 bandsPulsed UWB with 1 MHz PRF

Simulation results (1) 35 MSPS, rate 7/8 coding, no interleaving, Iuwb/N = -6 dB [XSI filing to FCC for

typical operating scenarios, Sept. 2003]

Very little different between UWB radios under realistic scenarios[Note: SINR=C/(N+Is+Iuwb), Is=satellite intra-system interference]

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Simulation results (2) 35 MSPS, rate 7/8 coding, no interleaving, Iuwb/N = -0.4 dB

MB-OFDM interference is consistently lower than impulse radio UWB system

4 5 6 7 8 9 1010

-5

10-4

10-3

10-2

10-1

100

SINR

Bit

Err

or R

ate

Interference comparison between various UWB waveforms

White Gaussian Noise InterferenceMB-OFDM with 3 bandsMB-OFDM with 7 bandsPulsed UWB with 1 MHz PRF

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Minimum separation between UWB radiosand FSS receivers: Example 1

I/N = -0.4 dB, antenna elevation angle = 5 degrees, rate 7/8 coding MB-OFDM transmitters can be placed closer than impulse radios

57 m59.2 m67.8 m

Satellite

2m

Closest allowed distance for I/N = -0.4 dB

5 degrees

Allowed by FCC

MB-OFDM 3-band

3m

69.6 mUWB device, DS-SS

UWB device, MB-OFDM, 3-band

UWB device, 1.3 MHz PRF impulse


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Minimum separation between UWB radiosand FSS receivers: Example 2

I/N = -0.4 dB, antenna elevation angle = 20 degrees, rate 7/8 coding MB-OFDM transmitters can be placed closer than impulse radios

Closest allowed distance for I/N = -0.4 dB

20.7 m21.6 m24.6 m

20 degrees

Satellite

Allowed by FCC

MB-OFDM

2m3m

25.2 m

UWB device, high PRFUWB device, MB-OFDM, 3-band

UWB device, 1.3 MHz PRF impulse


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Summary of FCC work FCC asked MB-OFDM proponents to analyze interference scenarios

Our studies for FSS systems, show that MB-OFDM causes similar (almost identical) interference compared to other UWB systems in realistic scenarios. MB-OFDM does not cause any interference beyond that which is anticipated by

current FCC rules.

FCC said that a proposed UWB approach would likely be deemed compliant if it could be shown that it would not cause levels of interference beyond that already anticipated by the rules.

MB-OFDM proponents believe MB-OFDM is FCC compliant and is allowed to transmit the full transmit power of -41.25 dBm/MHz. MB-OFDM does not have to reduce its transmit power by 4.7 dB as was claimed

by XSI.

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FCC Testing of MB-OFDM Presenter: Robert Sutton (TDK)

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FCC Testing FCC tests were performed on two different MB-OFDM radios (over 80 hours of lab time,

more than 300 measurements)

Tests performed at TDK RF Solutions EMC Test Services Lab

FCC Lab Registration No.: 94066

NVLAP Accreditation No.: 200430-0

Sample Measurements Performed:

UWB BandwidthRadiated Emissions, UWB Specific RequirementsEmissions in GPS BandsPeak EMI Within a 50 MHz BandwidthAC Mains Line-Conducted DisturbanceSpecialized (Conducted Antenna Terminal, Fully Anechoic)

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Test Plan ReferenceFCC CFR 47, Part 15, Subpart F Code of Federal Regulations, Part 15 Subpart F: Ultra-Wideband

Operation

FCC ET Docket 98-153, FCC 02-48 First R&O Revision of Part 15 of the Commission’s Rules Regarding Ultra-Wideband Transmissions Systems: First Report & Order

ANSI C63.4: 1992 Methods of Measurement of Radio-Noise Emissions from Low-Voltage Electrical and Electronic Equipment in the Range of 9 kHz to 40 GHz

FCC CFR 47, Part 15, Subpart C Code of Federal Regulations, Part 15 Subpart C: Intentional Radiators

FCC CFR 47, Part 15, Subpart B Code of Federal Regulations, Part 15 Subpart B: Unintentional Radiators

FCC CFR 47, Part 15, Subpart A Code of Federal Regulations, Part 15 Subpart A: General

CISPR 16-1 C.I.S.P.R. Specification for Radio Interference Measuring Apparatus and Measurement Methods

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Mandatory Test Environments

1m/3m Semi-Anechoic Chamber (RE)RF Shielded Chamber (CE)

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Alternative Test Environments

1m/3m Fully-Anechoic Chamber (RE)Conducted Antenna Terminal Bench (CE)

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Device and Measurement Configuration

The equipment under test physical setup was done as prescribed in ANSI C63.4

The equipment under test was operating in accordance with its intended usage as per FCC 2-48 First R&O

The equipment under test was configured to transmit at the mandatory data rate of 110 Mbps

The EMI Limits were in accordance with FCC Part 15, Subpart F

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UWB Bandwidth and Peak Radiated Emissions within a 50 MHz BW

Radio Sample 1

Test Distance: 1mDetector: PEAKRBW/VBW: 3 MHz/3 MHzMeas. Time: 1 msEmissions: < LimitUWB BW: > 500 MHz

Note: Data normalized to 3m test environment and 50 MHz RBW for limit comparison.

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Radiated Emissions UWB

Radio Sample 2

Test Distance: 1mDetector: RMSRBW/VBW: 1 MHz/3 MHzMeas. Time: 1 msEmissions: < Limit

Note: Data normalized to 3m test environment for limit comparison.

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Emissions in GPS Bands

Radio Sample 1

Test Distance: ConductedDetector: RMSRBW/VBW: 1 kHz/3 kHzMeas. Time: 1 msEmissions: < Limit

Note: Limit line is most stringent at 3m distance. No emissions above noise floor in radiated or worst case conducted measurement mode.

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AC Conducted Line Emissions

Radio Sample 2

Test Distance: ConductedDetector: PEAKRBW/VBW: 9 kHz/30 kHzMeas. Time: AutoEmissions: < Limit

Note: Standard AC conducted line measurements for coupled noise.

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Summary Representative data was presented from two radio samples that were shown to

be compliant with the most challenging of the UWB measurement test procedures

Additional EMI measurements (LF digital measurements) in accordance with FCC Part 15, Subpart C Intentional Radiators were performed

Additional EMI measurements (HF harmonic measurements) in accordance with FCC Part 15, Subpart F UWB Operation were performed

A series of tests in a fully anechoic chamber were performed to further prove compliance in an alternative measurement environment

Conducted antenna terminal tests were also performed

The EMC measurements performed under normal operating conditions met the FCC average and peak power limits

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Submission

Time to MarketPresenter: Jim Meyer (Alereon)

The Claims of Rapid TTM with the XSI Proposal You Have Heard Are at

Best Misleading

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Time to Market

“No Voters” expressed concerns about TTM XSI claims much faster TTM than MB-OFDM XSI claims its PHY is currently shipping XSI claims to be only company with UWB silicon Concerns expressed that MB-OFDM TTM would be

unacceptable to users XSI and Motorola propose a dual PHY standard and letting

the market sort it out

All MB-OFDM Supporters are Comfortable With MB-OFDM 1H’05 TTM

September 2003


doc.: IEEE 802.15-03/343r0

Submission

The Truth About TTM

The PHY Work Is Not the Critical Path

Elements Needed For A CompleteComplete Product1) PHY2) MAC3) Interoperability / Co-existence/Security4) Association / Authentication Models5) Applications interfaces (USB, 1394, WiMedia, etc)

We will work these in tandem to deliver a COMPLETE Product in early ‘05

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Time

PHY / MAC

Convergence Arch

PHY/MAC Interoperability

Applications

Connection Mgmt

1H 2003 2H 2003 1H 2004 2H 2004 1H 2005 2H 2005

Approx. Timeline For A WHOLE Product

Today, a proprietary bare pipe. A real product that won’t get returned? ‘05

WholeProduct

ProprietaryBarePipe

802.15.3aBarePipe

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Claim 1: “XSI can deliver almost immediately” Response

What are the odds?

16 silicon companies with 72 voters will agree

to a standard proposal without significant change

that gives one startup a time to market advantage

This proposal will not emerge without significant modification

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Claim 1 Response, continued

XSI failed to mention:1) The “shipping” PHY has never been describedand is substantially different from the current proposal2) Differences:

• Enhancements to the receiver for range• The merge elements from Parthus Ceva

3) The XSI PHY would require significant modificationsto be acceptable to the standards body - thereby eliminatingany PHY-related TTM advantage4) The XSI PHY is not FCC certified

The current “shipping” design is unacceptable

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Claim 1 Response, Cont.

Any company can take a non-standard or pre-standard product to market if: It passes FCC tests The IP situation provides the company and its customers

acceptable risk

A large portion of the UWB IP is available for the MB-OFDM proposal and resident within the companies supporting MB-OFDM

Working silicon is not a requirement for an IEEE standard as has sometimes been implied

CE5 did not establish early next year as their market horizon

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Claim (Experience):“XSI is The Only Company with

Working UWB Silicon”• Time Domain has 2 generations of shipping and FCC approved UWB silicon• Two Multiband OFDM compliant demos representingthe work of four companies are here today• 16 silicon companies who have a reputation forshipping successful products including all elements needed for success – not just chips – are supportersof the MB-OFDM proposal

XSI has consistently overstated their ability and experience

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Response to Suggestion of a Dual PHY Standard

Assume for a moment that you vote to split the standard and add dual PHYs as a necessary condition to obtain TTM. What are the implications?

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Implications:The Fight Continues and Intensifies

Splitting the standard makes life easy for the IEEE and hard for everybody else, especially the customer

1) Will the regulatory attacks stop?XSI/Motorola have already made new interference claims to the MMAC & FCC2) Will WiMedia, 1394 and USB endorse one PHY or two?3) Will there be one association/authentication model or two?4) How will the customers know who to believe?5) Interoperability/co-existence solutions between the two PHYs would add significant design complexity and cost.6) Manufacturers and distributors would have to stock multiple chips and products and produce in lower volumes.

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Implications:Fragmentation: Market Confusion in the Living Room

And Slow Adoption

And everyone can put 802.15.3a compliant on the box

Multiple Incompatible Radios (3+)Multiple Interoperability ForumsMultiple Application ForumsInteroperability and co-existance nightmaresMultiple Association/Authentication Schemes+Enormous Customer Confusion

September 2003


doc.: IEEE 802.15-03/343r0

Submission

ImplicationsDelays in Reaching Critical Mass

Multiple Radios

Time

Uni

ts

Single Radio

The market will decide so we don’t have to, but at what cost?

September 2003


doc.: IEEE 802.15-03/343r0

Submission

A Better Choice

September 2003


doc.: IEEE 802.15-03/343r0

Submission

1) Support of all major CE companies2) Support of all major silicon companies3) Provide a complete solution, not just chips4) Build a track record of performance, not undelivered claims5) Build a cohesive market that will support all vendors products6) Avoid confusing, slowing, and fragmenting the market 7) All the MB-OFDM companies will contribute the significant body of IP they possess to enable the market for everyone8) We can still compete vigorously in the market9) Companies who can get to market fastest with an acceptable product will be the winners and TTM won’t be damaged since the PHY is not the critical path

Work Together to Confirm and finish the Selected Proposal

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Intellectual Property Issue Presenter: Roberto Aiello (Staccato)

September 2003


doc.: IEEE 802.15-03/343r0

Submission

IEEE patent policy

Some voters have requested that we submit a Letter of Assurance for essential patents to the IEEE as condition to change their “No” votes

All author companies will conform to the IEEE patent policy. All companies will issue Letter of Assurance to the IEEE prior to the approval of the standard.

Most companies have already issued a Letter of Assurance to the IEEE.

September 2003


doc.: IEEE 802.15-03/343r0

Submission

SOP Performance Enhancement Presenter

Gadi Shor (Wisair)

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Overview Goals:

To enhance SOP performance for up to 3 interfering piconets across the range of mandatory data rates.

Replace the baseline mode at any given data rate with minimal impact on other performance metrics (e.g., range, complexity, power consumption, implementation feasibility, etc…).

July Proposal: Full PRF, 3- and 7-band modes with SIR estimation, Increased interleaver depth to 6 OFDM symbols (600 bits), 55, 110 and 200 Mbps (480 Mbps, optional).

Modified Proposal: Use Time-Spreading in place of conjugate symmetric spreading

Joint time and frequency diversity with suitable Interleaving Sequences; Coupled with increased bit-interleaver depth, mitigates the effect of symbol erasures due

to collision. Eliminate rotation sequences

Identified MAC mechanisms that can be used in identifying duplicate Interleaving Sequences

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Piconet A, IS = {f1,f2,f3,f1,f2,f3,repeat}

Piconet B, IS = {f3,f2,f1,f3,f2,f1,repeat}

Frequency domain spreading (frequency spreading rate ‘2’)

Information in A2 and B2 is lost due to collision

In-Band Frequency Spreading

A1

(A1)*

B1

(B1)*

A3

(A3)*

B3

(B3)*

A2B2

(A2B2)*

Collision

t

f1

f2

f3

piconetA

piconetB

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Time-Spreading

A1

B1 A2

B2

A1B1

Collision

t

f1

f2

f3

A2

B2 A3

B3

A3B3

piconetA

piconetB

Piconet A, IS = {f1,f2,f3,f1,f2,f3,repeat}

Piconet B, IS = {f3,f2,f1,f3,f2,f1,repeat}

Time domain spreading (time spreading rate ‘2’)

Remove conjugate symmetric spreading in frequency domain

200 coded bits per OFDM symbol with each symbol repeated in a different band according to the IS pattern.

September 2003


doc.: IEEE 802.15-03/343r0

Submission

G1

G2

G3

convolutional encoder

QPSK

mod.

200 coded bits per Block

200 Coded

bits

200

Coded bits

200

Coded bits

200

Coded bits

IS

Interleaver Design

200 coded bits per symbol interleaved over 3-symbol periods.

Puncture Interleave IFFT

Band1Band2Band3

September 2003


doc.: IEEE 802.15-03/343r0

Submission

1 2 3 1 2 3

1st200

codedbits

2nd200

codedbits

1st200

codedbits

2nd200

codedbits

3rd200

codedbits

3rd200

codedbits

Example

Combining (frequency diversity)

from G2

from G3

G1

G2

G3

Equivalent convolutional

encoder

Equivalent coding rate is 1/2

Interleaver Design (2)

Completely erasing 200 coded bits in 600 bits due to collision results in an

equivalent coding rate of ‘0.5’.

September 2003


doc.: IEEE 802.15-03/343r0

Submission

1 2 3 1 2 3

1st200

codedbits

2nd200

codedbits

1st200

codedbits

2nd200

codedbits

3rd200

codedbits

3rd200

codedbits

To avoid transmitting the same symbol in the same frequency (for achieving frequency diversity),

transmission for the time spreading is defined as follows:

1 3 2 1 3 2

1st200

codedbits

2nd200

codedbits

1st200

codedbits

2nd200

codedbits

3rd200

codedbits

3rd200

codedbits

1 1 2 2 3 3

1st200

codedbits

3rd200

codedbits

2nd200

codedbits

1st200

codedbits

2nd200

codedbits

3rd200

codedbits

1 1 3 3 2 2

1st200

codedbits

3rd200

codedbits

2nd200

codedbits

1st200

codedbits

2nd200

codedbits

3rd200

codedbits

IS_1 IS_2

IS_3 IS_4

Proposed Symbol pattern

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Preliminary Results – 2 SOPs

July Proposal Time-Spreading M-BOKi

dint/dref 110 Mbps 200 Mbps 110 Mbps 200 Mbps 114 Mbps 200 Mbps

3-Band 0.94 1.50 0.40i 0.50 0.62 0.59(?)

7-Band 0.49 0.78 0.30i 0.30i N/A N/A

Preliminary SOP results with 1-interferening piconet in CM3 (normalized) for data rates of 110 and 200 Mbps

MB-OFDM results obtained by full Monte-Carlo Simulation:

i. Acquistion limited

ii.Low Band results from XSI WPAN Proposal, IEEE 802.15-03/153r9, July-03

September 2003


doc.: IEEE 802.15-03/343r0

Submission

MAC Layer Techniques for Enhanced Piconet Isolation

Scan/Remote Scan Used in the event the PNC or a remote DEV detects the presence of a

duplicate Interleaving Sequence (i.e. another piconet using the same channel).

PNC scans the environment (and/or instructs remote DEVs to scan) to determine which piconets are in use.

Instructs the DEVs to move to a new channel as needed.

Superframe Shuttling Temporarily reduce the frame length to shift superframe boundaries relative

to one another enabling one device to listen for multiple beacons.

Other Child/neighbor piconets (akin to RTS/CTS??) to coordinate activity in

proximity of a receiver experiencing undue adjacent piconet interference. On a lightly loaded channel, determine the transmission pattern/periodicity

in neighboring piconets and adjust own transmission pattern accordingly.

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Complexity/Power Consumption/ Scalability

Presenter: Charles Razzell (Philips)

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Table of Contents

Multi-path energy capture using FFT vs. using RAKE linear equalizer

Digital Complexity of the major signal processing blocks FFT Viterbi Discussion of 802.11a PHY scaling with process technology

nodes How big is the digital PHY in the context of the total

system solution? Scalability (in power and complexity) Conclusions

September 2003


doc.: IEEE 802.15-03/343r0

Submission

FFT vs. Direct Linear Convolution Since the UWB channel is highly dispersive, efficient reception requires

coherently combining signal energy received at different times. This naturally leads to a RAKE or linear FIR filter structure in receivers

It has been known since ~1966 that high speed convolution and correlation is best performed using FFT/IFFT methods.

OFDM makes very efficient use of transforms: No overlap and save overheads

incurred in the size of required FFT Only one FFT block is used whether

transmitting or receiving (don’t need two transforms active simultaneously)

FFT makes a highly efficient energy collection engine at the heart of the MBOA proposal0 20 40 60 80 100 120 140

0

20

40

60

80

100

120

140

number of filter taps

mul

tiply

ope

ratio

ns p

er o

utpu

t sam

ple

FFT vs. direct linear convolution

FFT baseddirect linear

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Two Examples of Digital Energy Capture

RAKE receiver for DSSS (XSI) Computational cost of correlators

Each Correlator requires 24 additions/subtractions at the chip-rate (e.g., 1.368GHz)

For RAKE of length 5, need 8 x 5 = 40 correlators for 16-BOK

Computational cost of MRC (this occurs at symbol rate. E.g., 57MHz)

5 vectors of length 8 need to be multiplied by the corresponding 5 complex conjugate channel tap weights (one complex tap weight per vector).

5 x 8 x 57 = 2280 MOPS (non-trivial complex multiplies)

Overall 2280 MOPS (+ cost of 40 correlators running at the chip rate!)

FFT for MB-OFDM FFT part

Conservatively, this requires 8 complex multiplies and 22.4 complex adds per clock cycle at 128MHz

Looking at complex multiplies, we need 8 x 128 = 1024 MOPS

Frequency-domain EQ 100 data carriers multiplied by their

respective conjugate channel taps every 312.5ns

Implies 100/0.3125 = 320 MOPS

Overall: 1344 MOPS

MB-OFDM has “perfect” energy capture and is computationally less expensive.

September 2003


doc.: IEEE 802.15-03/343r0

Submission

XSI: Multi-path Energy Capture

Need about 12 RAKE fingers in CM4 and 6 RAKE fingers in CM3 for < 3 dB energy loss degradation. Further performance loss can be expected due to inter-chip interference, when a sparse RAKE is used.

September 2003


doc.: IEEE 802.15-03/343r0

Submission

FFT Complexity (Philips’ Estimates)# Approach

Preci-sion

No real Mult

Mult Cells

No real adds

Add Cells

No Regs

Reg Cells

Gates/Cell

Gates Mul

Gates Add

Gates Reg

Gates Total

% Shrink vs. #1

1Radix-2 10

bit10 32 120 44 10 256 10 10 38400 4400 25600 68400 0

2Radix-2 8

bit8 32 80 44 8 256 8 10 25600 3520 20480 49600 27

3Radix-4/ Radix-2

@128 MHz10 28 120 48 10 256 10 10 33600 4800 25600 64000 6

4Radix-4/ Radix-2

@152 MHz10 24 120 40 10 256 10 10 28800 4000 25600 58400 15

5as above,

8bit8 24 80 40 8 256 8 10 19200 3200 20480 42880 37

MBOA OFDM can be achieved at very modest gate counts for the FFT core.

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Based on information in P802.15-03/213r0 and P802.15-03/209r3

Gates Power

FFT 70-90k (SiWorks) 55-71 mW

56k (Staccato) 54.4 mW

64k (Philips) 50.7 mW

Viterbi 75k (SiWorks) 59 mW (> 200 Mbps)

29.7 mW (~ 100 Mbps)

80k (Staccato) 78 mW (480 Mbps)

<100k (Philips) 79 mW (480 Mbps)

Collated Complexity Estimates

Multiple companies have studied the complexity of the FFT and Viterbi cores dimensioned for the MBOA PHY. All results point to feasible and economic implementation in current CMOS processes.

September 2003


doc.: IEEE 802.15-03/343r0

Submission

802.11a vs. MB-OFDM complexity comparison

Approach taken: Start with publicly available 802.11a implementation area estimates Scale these numbers for CMOS process/clock rate/data rate etc.

variations Key points:

4 bit ADC vs. 10 bit ADC for 802.11a based on QPSK vs. 64-QAM, and other factors. This results in a scale factor of 40% for the signal processing area (assumed 60% of PHY) and no reduction for the bit processing area.

132 MHz BB clock rate vs. 40MHz for 802.11a. This results in a scale factor of 40/132.

Summary of BB die area comparison results: MB-OFDM PHY silicon area for 110 Mbps solution

Approx 86% of the area of the 802.11a PHY Calibration point: expected area of 802.11a PHY in 90nm is 2.6 mm2

September 2003


doc.: IEEE 802.15-03/343r0

Submission

MB-OFDM vs. IEEE 802.11a power consumption comparison

There are two significant components that differentiate the power consumption MB-OFDM versus IEEE 802.11a:

* Power consumption number scaled based on Intel ADC: 5-bit, 520 MHz (linear scaling for frequency, doubling of power for every bit).

MB-OFDM consumes 500 mW less at TX and at least 110 mW less at the receiver analog front-end when compared to IEEE 802.11a.

Block TFI-OFDM 802.11a

Power amp. N/A 500 mW

2 ADCs* ~28 mW

4-bit, 528MHz

~138 mW

9-bit, 80MHz

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Scalability

Data rate scaling: Data rates from 55 Mb/s to 480 Mb/s has been defined in the current

proposal.

Frequency scaling: Mode 1 (3-bands) and optional Mode 2 (7-band) devices. Guaranteed interoperability between different mode devices.

Power scaling: Implementers could always trade-off power consumption for range and

information data rate.

Complexity scaling: Digital section will scale with future CMOS process improvements. Implementers could always trade-off complexity for performance.

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Power Scaling (1)

In a time-spreading scheme the same information is repeated during two symbol durations for data rates of 55 Mbps, 110 Mbps and 200 Mbps.

Power savings can be obtained by turning OFF the receiver during the time repeated symbols at the expense of system performance. Majority of the digital section (except the Viterbi decoder) operates for only

50% of the time. Some of the analog components (LNA, mixer and ADC) can be switched off

for a portion of the OFF time. Settling/transition time is approx. 70 ns for ramp down and ramp up of LNA, mixer, and ADC in a 130 nm process expected off time is approx. 172.5 ns (27.6% of 625 ns).

3 dB penalty in performance due to not collecting the energy from both of the time-repeated symbols.

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Power Scaling (2) Power savings estimate for the 110 Mbps data rate with the receiver turned

OFF during the time-repeated symbols:

Can achieve a power savings of ~25% by paying a performance penalty of 3 dB.

Block High Performance Rx (ON for all time)

Low Performance Rx

(OFF during time-repetition)

RX AFE 121 mW 99 mW

RX Digital

84 mW 55 mW

RX Total 205 mW 154 mW

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Complexity Scaling (1) For 110 Mb/s, the MB-OFDM system has a 90% link success

probability distance in excess of 10 meters in all multi-path environments an excess margin of 3 dB for the 55 Mb/s mode.

Complexity and power consumption scaling can be achieved by carefully exploiting the excess margin. Illustrative example for 55 Mb/s:

Can reduce both the analog and digital complexity/power consumption by reducing the bit precision: Ex: reducing ADC precision from 4 bits 3 bits. Ex: reducing internal FFT precision (reducing the bit-precision of a multiplier

by 30% results in a complexity/power consumption savings of 50%).

ADC FFT FEQ

3 dB excess margin

4 bits 3 bits~0.5 dB Reduce internal precision

~2.5 dB

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Complexity Scaling (2)

Use of a 3-bit ADC results in ~0.5 dB of additional degradation when compared to the use of a 4-bit ADC.

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Conclusions on Scalability/Complexity

The “heart” of the Multiband OFDM proposal is an extremely efficient method of (de-)convolution based on the FFT

The FFT core is likely to require ~64k gates or less at quite modest clock speeds, according to multiple independent studies.

Studies also showed that the Viterbi core for 480 mbps is feasible in75-100k gates at the same clock speeds (~132MHz).

Requiring multiple correlators (or matched filters) running concurrently for MBOK detection adds a layer of complexity to the XSI/Parthus proposal that we avoid.

These gate counts should be considered in the context of the overall system solution including hardware assisted MAC.

Overall, the FFT gains us excellent, robust performance while remaining very economic to implement.

Several options are open to implementers to further scale complexity and power consumption in exchange for performance.

September 2003

Multi-band OFDM Proposal

doc.: IEEE 802.15-03/343r0

Submission

Clear Channel Assessment for Multiband OFDM

Presenter: Vern Brethour (Alereon)

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Overview of Clear Channel Assessment (CCA)

Multi-band OFDM CCA detector

Evaluation of XtremeSpectrum CCA

CCA Summary

CCA OutlineCCA Outline

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Indicates co-channel DEV transmitting Required for CSMA/CA to reduce collisions

Used w/ randomized backoff algorithm Typically integrated w/ RX state machine

CCA is the core of contention based MACs e.g., 802.11

In the 15.3 MAC, CCA only gates TX in CAP

Overview of CCAOverview of CCAWhat is CCA?What is CCA?

September 2003


doc.: IEEE 802.15-03/343r0

Submission

CCA sources, usually “ORed” together: Raw Energy Detect on “channel” (error prone) Receiving data after preamble (better) Virtual Carrier Sense (best)

Overview of CCAOverview of CCAThe 3 traditional flavors of CCAThe 3 traditional flavors of CCA

PHY Preamble PHY HeaderRate Length

Mac hdr/data Data/FCS

CCA-ED

CCA-DATA

CCA-VCS

SIGNAL

CCA

C. Brabenac, 05Aug2003

Ideal CCA scenario — strong, error free signal

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Overview of CCAOverview of CCAVirtual Carrier Sense (best source)Virtual Carrier Sense (best source)

Calculated duration of frame (Rate * Length) from PHY header used

PHY preamble/header must be received After that, oblivious to dropouts!

Works even if data rate not supported by receiver! PHY header is always at “base rate”

Usage is well defined in 802.11a Not yet mentioned in 802.15.3 MAC spec!

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Overview of CCAOverview of CCAPreamble/data received (good source)Preamble/data received (good source)

PHY preamble must be received OK After that, driven by modulated symbols still arriving

Works if PHY header corrupted (preventing VCS)

After PHY/MAC header, only works if DEV can demodulate at transmitted rate

Functions >= RX threshold

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Overview of CCA“Energy detect” (poorest source)

Detects anything transmitted on channel Preamble can be missed (no data history) Channel coherency can be lost

Helpful if no VCS (PHY hdr corrupt)

Traditionally a “Close proximity” CCA Threshold typically (RX threshold + 20dB) to

achieve tolerable false BUSY

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Overview of CCAOverview of CCAUpshot on the 3 sourcesUpshot on the 3 sources

VCS and preamble/data driven CCA: Any PHY with a working receiver can/should

do both of these easily “Energy detect” CCA:

Very tough to do for UWB Some have suggested cases for slotted Aloha

fallback (XtremeSpectrum proposal) Others have suggested preamble & VCS methods

are adequate (Sony proposal) May help pathological cases, so worth

investigating *IF* performance is adequate

September 2003


doc.: IEEE 802.15-03/343r0

Submission

RequirementsDescriptionPerformance under multi-pathPerformance under MAI

Multi-Band OFDM CCA DetectorMulti-Band OFDM CCA DetectorOutlineOutline

September 2003


doc.: IEEE 802.15-03/343r0

Submission

MB OFDM performs “Preamble based CCA” using efficient hierarchical correlator detector

Energy detection in channel required for “Energy based CCA” inside a packet Option for use as pre detector for the correlator detector

Detector should detect energy inside the channel Channel is defined by the TFI sequence Detector should be triggered only if TFI sequence is detected

Multi-band OFDM CCA DetectorMulti-band OFDM CCA DetectorRequirements(1)Requirements(1)

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Low power consumption

Fast: works in several uSec

Works in multipath conditions

Works in the presence of frequency error between the transmitter and the receiver (40 ppm)

Works in the presence of NBI

Works in the presence of MAI from other piconets

Should have programmable threshold

Multi-band OFDM CCA DetectorMulti-band OFDM CCA DetectorRequirements(2)Requirements(2)

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Graph presents all three frequencies after time alignment according to the expected TFI sequence

Detects “Busy” only if all three are above the threshold at the same time Reduce chances for False Alarms even when two out of three bands are jammed

by NBI or MAI from a second piconet. Detects energy in each sub-band: robust to multi-path and frequency errors

Multi-band OFDM CCA DetectorMulti-band OFDM CCA DetectorDescriptionDescription

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Detector identifies the existence of energy in a given channel (TFI sequence)

Detector searches for energy in several sub-bands. Detection period is 5.6 uSec.

The detector detects “busy” only if energy appears in all sub-bands in the correct relative time (based on the TFI sequence)

Multi-band OFDM CCA DetectorMulti-band OFDM CCA DetectorDescription(1)Description(1)

September 2003


doc.: IEEE 802.15-03/343r0

Submission

The detector works in several stages to minimize power consumption

First stage detects energy in a single band

Second stage search for energy in other sub-bands based on the expected TFI sequence

Multi-band OFDM CCA DetectorMulti-band OFDM CCA DetectorDescription(2)Description(2)

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Multi-band OFDM CCA DetectorMulti-band OFDM CCA DetectorPerformance: CM1, Single Piconet, SNR=-5Performance: CM1, Single Piconet, SNR=-5

September 2003


doc.: IEEE 802.15-03/343r0

Submission


September 2003


doc.: IEEE 802.15-03/343r0

Submission

Multi-band OFDM CCA DetectorMulti-band OFDM CCA DetectorPerformance: CM1, Two Piconets, SNR=-2Performance: CM1, Two Piconets, SNR=-2

September 2003


doc.: IEEE 802.15-03/343r0

Submission


September 2003


doc.: IEEE 802.15-03/343r0

Submission

MB-OFDM proposal supports “Energy based CCA”

Detector utilize the TFI sequences to improve reliability

Detector performs well under multi-path conditions and frequency error

Detector can tolerate NBI and MAI from a second piconet

Detector can detect MAI and switch to a “Preamble based CCA”

Multi-band OFDM CCA DetectorMulti-band OFDM CCA DetectorSummarySummary

September 2003


doc.: IEEE 802.15-03/343r0

Submission

MB-OFDM supports CCA.What about XSI’s Proposal?

In San Francisco, XSI showed very good results for CCA based on using their regular chipping rate as the detectable structure.

Different chipping rates for different channels allow simultaneous discrimination of all piconets on the air.

The CCA circuitry should be very power efficient.

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Block diagram courtesy of XtremeSpectrum, Inc. Document 03/153 r10 dated July 2003

BPF ( )2 BPF | Detect

BPF | Detect

BPF | Detect

BPF | Detect

LO


Review of their approachReview of their approach

September 2003


doc.: IEEE 802.15-03/343r0

Submission

LO frequency chosen arbitrarily as 4.075GHz: 4.095GHz => 20MHz, 4.101GHz => 26MHz 4.107GHz => 32MHz, 4.113GHz => 38MHz Results are independent of LO frequency

After squaring circuit, 2x frequencies are: 40MHz, 52MHz, 64MHz, 76MHz

Four BP filters centered at 2x frequencies 200kHz 4th order Chebshev type 1 Filter output squared and integrated for 5us

No shadowing


Simulation DetailsSimulation Details

September 2003


doc.: IEEE 802.15-03/343r0

Submission

Easily detectable energy in 200kHz band at IF of 40MHz.

Consistent with XtremeSpectrum

results.

Evaluation of XtremeSpectrum CCAFree Space LO = 4.095 GHz

PSD of Squaring Circuit Output

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No detectable energy at the anticipated frequency, despite high SNR (+8dB).

Evaluation of XtremeSpectrum CCACM1, CIR#53; pico-net LO = 4.095 GHz

PSD of Squaring Circuit Output

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What Went Wrong in Multipath?

x(t) = squaring circuit input

Output = y(t) = x(t)^2 = x(t) . x(t) Multiplication in the time domain is

convolution in the frequency domain: X(f) = dft(x(t)) Y(f) = X(f) * X(f) = dft(x(t)^2)

Y(f0) = Σ (X(f) . X(-f + f0))

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Evaluation of XSI CCA: Test Channel Used to Explain the Failure

Mechanism20ns echo

Nulls every 50MHz

September 2003


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Evaluation of XSI CCA: Fc = 4.095GHz, LO = 4.075GHz

IF = 20MHz, 2xIF = 40MHzGreen curve is

mirror image of blue curve, shifted

right 40MHz

Multiplying and accumulating yields the squaring circuit output; 40MHz content is easily detectable.

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IF = 26MHz, 2xIF = 52MHz

Green curve is mirror image of

blue curve, shifted right 52MHz


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Multiplying and accumulating yields the squaring circuit output; 76MHz content is not easily detectable.

Note the peak-to-null alignment of the 50MHz nulls that were introduced by the channel.



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The synthetic “echo” test channel produces a scenario where a piconet with LO = 4.113GHz has much lower probability-of-detection than do piconets at 4.095, 4.101, or 4.107GHz

Does this scenario occur in CM1,2,3,4? YES

Evaluation of XSI CCA:

Results in CM1,2,3,4Results in CM1,2,3,4

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XSI result in CM1 @ 4m, 4.1GHz, “r^2 mean path”

Evaluation of XSI CCA: Average ROC Curves, CM1, SNR = +8dB

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XSI result in CM1 @ 4m, 4.1GHz, “r^2 mean path”

Evaluation of XSI CCA: Average ROC Curves, CM1, SNR = 0dB

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0.85

XSI result in CM2 @ 4m, 4.1GHz, “r^2.5 mean path”

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Evaluation of XSI CCA: So What’s the Issue?

In July, XSI showed hopeful results.

We have independently validated their results.

The problem is in showing AVERAGE results.

Original selection criteria called out link probabilities of 90%.

The CE companies want us to be showing results for 95%.

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Evaluation of XSI CCA: 95% ROC curves, CM1, SNR = +8dB

5% of CIRs in CM1 are worse than this

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Evaluation of XSI CCA: 87% ROC curves, CM1, SNR = 0dB


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200kHz / 4.113GHz = 48.6 ppm,100kHz / 4.113GHz = 24.3 ppm,100kHz / 8.226GHz = 12.15 ppm Narrow bandwidth of target frequency in the

squaring circuit output means that even modest LO frequency offsets cause significant CCA performance degradation.

4 dB loss at 20 ppm (+10 ppm at Tx, -10 ppm at Rx) 13 dB loss at 40 ppm (+20 ppm at Tx, -20 ppm at Rx)


Another Issue: oscillator tolerance

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Evaluation of XSI CCA: Filters Used for Detecting Coherent Energy

Generated by the Squaring Circuit

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Evaluation of XSI CCA: Situation with No LO Error

(SNR would be Slightly Better if Filter Were Narrower)

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Submission

Evaluation of XSI CCA: Situation with +/- 10ppm LO Error

(Now the Wider Filter Bandwidth is Helping)

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Evaluation of XSI CCA: Situation with +/- 20ppm LO Error

(Rapidly Falling Outside Filter Passband)

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+/- 10ppm LO error

September 2003


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Evaluation of XSI CCA: 90% ROC curves, CM1, +8 dB, +/-

10ppm


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+/- 20ppm LO error

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Evaluation of XSI CCA: 75% ROC curves, CM1, +8 dB, +/- 20ppm


September 2003


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+/- 20ppm LO error

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Summary of XSI Squaring Circuit CCA Mechanism

Works well under ideal conditions Suffers in the presence of multi-path Suffers in the presence of LO mismatch Many channels fail even at high SNR Performance problems demonstrated in

CM1 for the low frequency band Worse in CM2, CM3, CM4 Worse in the high (8.2GHz) frequency band

Not a reliable CCA mechanism

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The best CCA forms are VCS and preamble/data Energy detect driven CCA is nice addition, if a UWB

solution possible

There is a good CCA solution for MB OFDM! Performs well in multipath Is challenged by SOP, but this is detectable w/ fallback

to preamble/VCS methods

The XtremeSpectrum CCA is not reliable Very challenged in multipath (CM2->CM4), and even in

many CM1 channel realizations No practical detection / fallback methods

CCA SummaryCCA Summary

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MAC Enhancements for Multiband OFDM

Presenter Larry Taylor (Staccato Communications)

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Transparency to 15.3

Value-add enhancements Band management / frequency agility Ranging support

MAC Enhancement Conclusions

MAC Enhancement OutlineMAC Enhancement Outline

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Multi-band OFDM PHY has default modes Band management is part of an optional

value-add story

MAC functional behavior can stay the same as before E.g., rate selection and capability probing

mechanics are unchanged

Transparency to 15.3Transparency to 15.3OverviewOverview

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As per MAC convention, chosen by index Associated to 4 bits defined in PHY header Rate is independent of band management!!

Transparency to 15.3Transparency to 15.3Transmitter rate selectionTransmitter rate selection

Rate Index Data Rate

Coding Rate

Spreading Rate

Information Tones

0 (mandatory 55 11/32 4 25 1 80 1/2 4 25 2 (mandatory) 110 11/32 2 50 3 160 1/2 2 50 4 (mandatory) 200 5/8 2 50 5 320 1/2 1 100 6 480 3/4 1 100 7 – 15 TBD TBD TBD TBD

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Uses same rate capability bits as before Described in 15.3, section 7.4.11

Proposed rate encoding:

Transparency to 15.3Transparency to 15.3Rate capability probingRate capability probing

Value Supported Rates (Mbps)

Comments

0 55, 110, 200 Mandatory rates 1 55, 80, 110, 160, 200 ½ rate coding added 2 55, 80, 110, 160, 200, 320 Spreading_rate = 1 added 3 55, 80, 110, 160, 200, 320,

480 ¾ rate coding added

4-31 Future Future rates

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Multi-band OFDM inherently suitable for performing controlled frequency agility Selective usage of bands

Great for “good neighbor” behavior or regulatory configuration Bands can be punctured to address severe near-far

scenarios Optional enhancements to be developed:

Primitives to support local and remote band assessment on a per band basis (RSSI, LQI)

Primitives to support band usage on a per piconet basis

Primitives to support code puncturing on a per stream basis

Band capability bit definitions for 7.4.11

Value-add enhancementsValue-add enhancementsBand management / frequency agilityBand management / frequency agility

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Ranging option requires a new MAC command Ranging request/response Includes sequence numbers

New MLME primitives needed to initiate request and obtain response

See ranging summary for more details

Value-add enhancementsValue-add enhancementsMAC support for RangingMAC support for Ranging

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Transparency to 15.3 Multi-band OFDM PHY default mode

requires no new MAC functional behavior

Value-add enhancements (optional) Band management / frequency agility,

and ranging

MAC Enhancement MAC Enhancement ConclusionsConclusions

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Symbol DefinitionPresenter: Anuj Batra (TI)

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Symbol Definition Outline

Revisit the definition and purpose of the user-defined pilots as defined in the MB-OFDM proposal.

Examine more closely the transmitter back-off requirements for the MB-OFDM proposal.

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OFDM Parameters: 128-point FFT

128 total tones: 100 data tones used to transmit information (constellation: QPSK) 12 pilots tones used for carrier and phase tracking 10 guard tones (used to be known as dummy tones) 6 NULL tones

Exact use of guard tones is left to implementer – adds a level of flexibility in the standard.

Example: QPSK constellation is transmitted on the 10 guard tones. Power levels can be adjusted to help relax filtering requirements. Modulated using the same pseudo-random sequence that is used to

modulate the pilot tones ensure that there are no spectral lines.

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Guard Tones

Guard tones is a more appropriate name for the these tones.

Advantages of using guard tones: Can relax the analog transmit (DAC filters) and receive filters, including the

anti-aliasing and the pre-select filters. Helps to relax filter specifications for adjacent channel rejection. Can be used to help reduce peak-to-average power ratio simplifies the

design of the DAC and driver. Could be used to transmit proprietary information (data/signaling). Other inventive ideas we can be creative!

If data is mapped onto the guard tones, then this scheme is analogous to the concept of Excess Bandwidth as used in Single-carrier Systems. Received signal in guard tones can be combined appropriately with the

remaining information data tones to improve performance.

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Back-off at the Transmitter

According to Document 03/153r9, both of the proposals presented in July require a back-off at the transmitter:

This is absolutely correct!

In the MB-OFDM proposal, the cyclic prefix introduces structure in the transmitted system, which results in ripples in the power spectral density (approx. 1.3 dB).

There is a simple solution for removing the ripples in PSD of the OFDM signal.

Note that there is NO way to eliminate the PSD ripple in the CDMA proposal.

FEATURE XSI MB-OFDM

PSD Backoff 1.3 to 2.2 dB

(1.7 dB for 114 Mbps)

1.3 dB

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Zero-Padded Prefix (1)

Using a zero-padded (ZP) prefix instead of a cyclic prefix is a well-known and well-analyzed technique.

Recall that the OFDM with cyclic prefix is created by pre-appending the last 32 samples of IFFT output:

A ZP-OFDM signal is created by pre-appending 32 zeroes to the IFFT output.

s96s1 s2 s95s3 s94 s128s97

s128s97

Cyclic Prefix IFFT Output

s96s1 s2 s95s3 s94 00 s128s97

Zero-PaddedPrefix

IFFT Output

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Zero-Padded Prefix (2)

Zero padded prefix removes the structure in the transmitted signal No Ripples in the PSD.

Power spectral density for a ZP-OFDM signal:

Hence, a Zero-padded Multi-band OFDM system does NOT require any back-off at the transmitter.

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Zero-Padded Prefix (3) A Zero-Padded Multi-band OFDM has the same multi-path robustness as a system

that uses a cyclic prefix (60.6 ns of protection).

The receiver architecture for a zero-padded multi-band OFDM system requires ONLY a minor modification (less than < 200 gates).

Added flexibility to implementer: multi-path robustness can be dynamically controlled at the receiver, from 1.9 ns up to 60.6 ns.

Channel+

OFDM Signal

IFFTOutput

CP

`

+

FFT Input

Same

WithCP

Channel `

+

FFT Input

Copy

WithZP +

OFDM Signal

IFFTOutput

ZP

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Performance of a Zero Prefix

The distance at which the Multi-band OFDM system can achieve a PER of 8% for a 90% link success probability is tabulated below:

Same performance as a cyclic prefix based MB-OFDM system that does not back-off at the transmitter.

Notes:1. Simulations includes losses due to front-end filtering, clipping at the DAC, DAC precision, ADC

degradation, multi-path degradation, channel estimation, carrier tracking, packet acquisition, overlap and add of 32 samples (equivalent to 60.6 ns of multi-path protection), etc.

2. Increase in noise power due to overlap and add is compensated by increase in transmit power (1 dB) same performance as an OFDM system using a cyclic prefix.

Range* AWGN CM1 CM2 CM3 CM4

110 Mbps 20.5 m 11.4 m 10.7 m 11.5 m 10.9 m

200 Mbps 14.1m 6.9 m 6.3 m 6.8 m 4.7 m

480 Mbps 7.8 m 2.9 m 2.6 m N/A N/A

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Ranging with MB-OFDMPresenter: Dave Leeper (Intel)

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MB-OFDM Ranging

Eliminating the turnaround latency issue

Obtaining high accuracy/precision ranging from MB-OFDM-based systems

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UWB Ranging via Two-Way Time Transfer*Results are Independent of “Turnaround-Time Latency”

Device A Device B

Two equations in two unknowns yield:

* US Naval Observatory, Telstar Satellite, circa 1962http://www.boulder.nist.gov/timefreq/time/twoway.htmUnmatched detect-delays in the two devices may require one-time offset calibration.

ptUnknown propagation delay

poATBR ttTT 11

Unknown clock offset 0tMessage 1

Message 2

BRBTATARp TTTTt 121221

poBTAR ttTT 22

ATARBRBTo TTTTt 121221

Multiple measurements of tp

and to yield finer precision &

accuracy, and allow frequency offset correction.

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SystemView

0

0

250e-9

250e-9

500e-9

500e-9

750e-9

750e-9

1e-6

1e-6

1.25e-6

1.25e-6

100

80

60

40

20

0

Am

plit

ude

Time in Seconds

127-bit PRBS Matched Filter Rel Power OutputSystemView

925e-9

925e-9

950e-9

950e-9

975e-9

975e-9

1e-6

1e-6

1.025e-6

1.025e-6

1.05e-6

1.05e-6

1.075e-6

1.075e-6

100

80

60

40

20

0

Am

plitu

de

Time in Seconds

127-bit PRBS Matched Filter Rel Power Output

SystemView

0

0

250e-9

250e-9

500e-9

500e-9

750e-9

750e-9

1e-6

1e-6

1.25e-6

1.25e-6

50

0

-50

-100

Am

plitu

de

Time in Seconds

Received Phase Angle on Power Peaks

A A A IA A …

A = 127-bit PRBS Inverted A

Time T “Strobes” Generation SimulationMultipath: Typical CM1 Channel; Noise: AWGN, 0 dB SNR

Time Quantized To: 1 / (528 MHz) = 1.9 ns stepsMax Quantizing Error ~ 1 ns => tp accuracy ~ 1 ns ~ 30 cm / measurement

Simplified Preamble

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Precision “Vernier” for Ranging(Byproduct of Sample Timing Clock Adjustment)

Sampler

SamplingClock

Phase Adjust

FIRBaseband

SignalFIR Matched to

Preamble Sequence

Vernier ReadoutStep Size = 250 ps or Less

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A A A IA A …

A = 127-bit PRBS Inverted A

Time T “Strobes” Generation SimulationMultipath: CM3 Channel #20; Noise: AWGN, 0 dB SNRSome Channels will Require Carefully Set Thresholds

Simplified Preamble

SystemView

0

0

250e-9

250e-9

500e-9

500e-9

750e-9

750e-9

1e-6

1e-6

1.25e-6

1.25e-6

5

4

3

2

1

0

Am

plitu

de

Time in Seconds

127-bit PRBS Matched Filter Rel Power OutputSystemView

995e-9

995e-9

1.045e-6

1.045e-6

1.095e-6

1.095e-6

5

4

3

2

1

0

Am

plit

ud

e

Time in Seconds

127-bit PRBS Matched Filter Rel Power Output

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MB-OFDM Ranging Summary TWTT removes the issue of “turnaround latency”.

MB-OFDM preamble alone enables ranging accurate to ~1 foot (30 cm) per measurement. Addition of sampling-clock phase-correction vernier yields precision better than 10 cm.

Techniques to yield even finer resolution per measurement are under study at Sony, U.Minn.

Multiple measurements over multiple 528 MHz sub-bands will enable preamble-ranging accuracy & precisions to 10 cm or better.

Conclusion: MB-OFDM is fully capable of high accuracy/precision ranging.

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Conclusions We have addressed all major points raised by the no-voters FCC asked MB-PFDM proponents to analyze interference scenariosl

Our studies show that MB-OFDM have similar (almost identical) effect compared to other UWB systems allowed by the rules

FCC said that a proposed UWB approach would likely be deemed compliant if it could be shown that it would not cause levels of interference beyond that already anticipated by the rules.

MB-OFDM proponents believe MB-OFDM is FCC compliant and is allowed to transmit the full transmit power of -41.25 dBm/MHz.

This PHY proposal has the support of all major CE and silicon companies that will ensure no delay in the deployment of products based on this PHY

Some technical enhancements were presented Time spreading, Interleaver design and zero padded cyclic prefix

Clarifications to concerns by no-voters in the following areas were addressed Guard tones, SOP, CCA, MAC, complexity, power consumption, scalability

and location awareness.

Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)

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Transcript of Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)