july 2007 doc.: ieee 802.15-07-0766-00-003c project: ieee ......mrt1 2000 mbps ofdm mode mrt2 2500...

July 2007

France Telecom - IHPSlide 1

doc.: IEEE 802.15-07-0766-00-003c

Submission

Project: IEEE P802.15 Working Group for Wireless Personal Area NProject: IEEE P802.15 Working Group for Wireless Personal Area Networks (etworks (WPANsWPANs))

Submission Title: [France Telecom - IHP OFDM mode definition]

Date Submitted: [7 May 2007]

Source: [ Pascal Pagani1, Maxim Piz2,

Isabelle Siaud1, Eckhard Grass2,

Wei Li1, Klaus Tittelbach-Helmrich2 ,

Anne-Marie Ulmer-Moll1, Frank Herzel2,

Marie-Hélène Hamon1]

Company [1 France Telecom, 2 IHP]

Address []

Voice: [], Fax: [], E-Mail: []

Re: []

Abstract: [Proposition of a high data rate wireless system in the 60 GHz range.]

Purpose: []

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.

July 2007


doc.: IEEE 802.15-07-0766-00-003c

Submission

France Telecom – IHP TG3c Proposal

OFDM Mode Definition

July 2007


doc.: IEEE 802.15-07-0766-00-003c

Submission

Motivation

• France Telecom – IHP has agreed to create a joint submission with COMPA

• The proposed system features an LDR commonmode and both SC and OFDM HDR modes

• This document details FT-IHP OFDM modes

• Main features

– One mandatory channel size of 2 GHz and two possible optional channel sizes (500 MHz or 1 GHz)

– Data rates from 187.5 Mbps to 6 Gbps for applications suchas video streaming, file transfer, home network distribution or in-vehicle media supply

– OFDM based system providing high spectrum efficiency

– Scalable parameters for increased robustness

July 2007


doc.: IEEE 802.15-07-0766-00-003c

Submission

Channel Plan

1 2 4

240

MHz

120

MHz

816 MHz

1080 MHz

3

57 58 59 60 61 62 63 64 65 66 fGHz

Ch

#B1

Ch

#B2

Ch

#B3

Ch

#B4

Ch

#B2

57 58 59 60 61 62 63 64 65 66

fGHz

520 MHz

Ch

#B1

Ch

#B3

Ch

#B5

Ch

#B4

Ch

#B6

Ch

#B8

Ch

#B7

Ch

#B9

1040 MHz

Ch

#B11

Ch

#B10

Ch

#B12

• Mandatory channels: four 2 GHz channels

• Option #1 (recommended option): 500 MHz sub-channels

• Option #2: 1 GHz sub-channels

July 2007


doc.: IEEE 802.15-07-0766-00-003c

Submission

Applications

• Uncompressed video streaming (UM1)

• Kiosk file downloading (UM5)

• High data rate WPAN distribution

– Multiple user high data rate networking

– Home or office video streaming

– Express file transfer

LiveBox

home gateway

AP

UWB

AP

60 GHz 60 GHz

Shadow • Media supply in trains,

busses and aircraft

– Possibly use of

secondary system

(e.g. UWB) for 100%

coverage

July 2007


doc.: IEEE 802.15-07-0766-00-003c

Submission

PHY Baseband Architecture

• OFDM system architecture

Binary

source

Data

scrambler

Binary

interleaver

Constellation

Mapping

Tone

interleaver

S->P

Pilot

inser-

tion

IFFT P->SCP

insertion

cos(2πfct)

DAC

Guard

sub-carriers

insertion

FEC(Convolutional,

LDPC, TC)

July 2007


doc.: IEEE 802.15-07-0766-00-003c

Submission

System Parameters

1120 ns / 1184 ns / 1244 ns1120 ns / 1184 ns / 1244 ns1120 ns / 1184 ns / 1244 nsSymbol interval (TSYM

)

96 ns / 160 ns / 220 ns96 ns / 160 ns / 220 ns96 ns / 160 ns / 220 nsCyclic prefix duration

(TCP

)

1024 ns1024 ns1024 nsIFFT/FFT period

0.977 MHz0.977 MHz0.977 MHzSubcarrier frequency

spacing

2 GHz1 GHz500 MHzChannel bandwidth

(BFFT

)

20481024512FFT size (NFFT

)

23111354Number of guard

carriers

555Number of DC zero

carriers (NDC)

1326633Number of pilot carriers (N

SP)

1680840420Number of data

subcarriers (NSD

)

2 GHz channels1 GHz channels500 MHz channelsParameter

July 2007


doc.: IEEE 802.15-07-0766-00-003c

Submission

Modulation and Coding Schemes

2102/364-QAM1500 Mbps

1755/616-QAM1250 Mbps

1402/316-QAM1000 Mbps

1051/216-QAM750 Mbps

702/3QPSK500 Mbps

52.51/2QPSK375 Mbps

352/3BPSK250 Mbps

26.251/2BPSK187.5 Mbps

Data bytes

per OFDM

symbol

Coding RateModulationData Rate

Valid for CP duration of 96 ns.

500 MHz channels

July 2007


doc.: IEEE 802.15-07-0766-00-003c

Submission


4202/364-QAM3000 Mbps

3505/616-QAM2500 Mbps

2802/316-QAM2000 Mbps

2101/216-QAM1500 Mbps

1402/3QPSK1000 Mbps

1051/2QPSK750 Mbps

702/3BPSK500 Mbps

52.51/2BPSK375 Mbps

Data bytes

per OFDM

symbol



1 GHz channels

July 2007


doc.: IEEE 802.15-07-0766-00-003c

Submission


8402/364-QAM6000 Mbps

7005/616-QAM5000 Mbps

5602/316-QAM4000 Mbps

4201/216-QAM3000 Mbps

2802/3QPSK2000 Mbps

2101/2QPSK1500 Mbps

1402/3BPSK1000 Mbps

1051/2BPSK750 Mbps

Data bytes

per OFDM

symbol



2 GHz channels

July 2007


doc.: IEEE 802.15-07-0766-00-003c

Submission

Preamble Format and Utilization

Preamble Part 1 Pr. Part 2 SF Data Payload

A A A A A A A A A A A A A A A A A A

-A -A-A -A -A -A -A -A

8 A-symbols for

• AGC settling

11 A-symbols + 13 inverted A-symbols for

• frame detection

• frequency correction

• coarse frame synchronization

-A -A -A -A

A

-A

T1 = 1.024µs T2 = 3.072µs

CP(B) B B

2 long B-symbols for

• channel estimation

• fine frame synchronization

• (fine frequency estimation)

T3 = 0.384 µs + 2.048µs

Tpreamble = 6.528 µs

July 2007


doc.: IEEE 802.15-07-0766-00-003c

Submission

Frame Detection Mechanism

A’ A’ A’ A’ A’ A’ A’ A’ A’ A’ A’ A’ A’ A’ A’ A’ A’ A’ A’ A’ A’ A’ A’ A’

-A’-A’-A’-A’-A’-A’-A’-A’-A’-A’-A’-A’

A’


-A’ -A’-A’-A’-A’ -A’-A’-A’-A’-A’-A’-A’

A’

short ACFdelayed short ACF

short ACFdelayed short ACF

first peak

second peakR11 R12

R31

R21

R22

R32

R41 R42

],[ maxmin1 DDxx kk ∈−+

• a normalized autocorrelator is related to a delayed version

• samples satisfying an “antiphase-condition” are marked

• marked samples are grouped in clusters, such that the distance of

adjacent cluster samples is below some value d

• the middle point in each cluster is defined as a peak at position xk

• two peaks must be found in the frame with a distance

• with the first peak as a time reference, a second ACF is evaluated

for final frame detection and frequency offset correction


-A’-A’-A’-A’-A’-A’-A’-A’-A’-A’-A’-A’

A’

Applying second (long) ACF for frequency correction and final frame detectionSTEP 1

STEP 2

July 2007


doc.: IEEE 802.15-07-0766-00-003c

Submission

Channel Coding

• Convolutional encoder should be used for lowcomplexity implementation

• We propose to use an outer Reed-Solomon code with a code rate of about 95% to reduce the error

floor.

• Possibly, the convolutional codes can be replaced by

advanced codes:

– Turbo Codes

– LDPC codes

July 2007


doc.: IEEE 802.15-07-0766-00-003c

Submission

Binary Interleaving

• Optimized binary interleaver based on an iterative structure

• Effectively maximizes both intra- and inter- symbols interleavingspreading

• Efficiently improves decoder performance

( )

, ( )j

p qI k(2)

, ( )p q

I k

I I Ik I

, ( )p qI k

( )

, ( )j

p qI k(2)

, ( )p q

I k

I I Ik I

, ( )p qI k

( ) ( )( )

( ) [ ][ ]

( ) [ ][ ]KK

j

qp

j

qp

KKqp

j

qpINOUT

IpkpqkkI

kpkpqkkI

kIXkX

)1(

,

)(

,

)0(

,

)(

,

−⋅−−⋅⋅++=

⋅−−⋅⋅++=

=

α

α

parameterOffset :

parametersr Interleave : , ,

size,Block :

p

K

jqp

K

<α

July 2007


doc.: IEEE 802.15-07-0766-00-003c

Submission

Tone Interleaving

• After constellation mapping, the complex symbols assigned to different frequency tones are interleaved over 1 or 4 OFDM symbols

• Purpose : increase the system frequency diversity and reduceinterference from narrow band interferers

• Similar interleaving scheme is used as for binary interleaving

• Dynamic implementation: two different permutation rules are usedcyclically

Permutation rule #1 Permuation rule #2 Permutation rule #1 Permuation rule #2

#2#1 #4#3OFDM symbol

Two different permuation rules

f

f

f

f

YOUT

(k)=YIN

(L(k))

L1(k) L2(k)

July 2007


doc.: IEEE 802.15-07-0766-00-003c

Submission

OFDM Pilot Tones

• Channel estimation symbols and OFDM pilot tones carry highlysensitive information for the mitigation of channel and RF impairments

• It is recommended to allocate more power to these signals

• In addition, pilots should be assigned to different subcarriers in successive OFDM symbols, for a more efficient estimation of phase noise and frequency offsets ("Traveling pilots")

• These concepts have been implemented and assessed in the WiMax system (IEEE 802.16).

Example of travelingpilot scheme(from IEEE 802.16)OFDM symbol #1

OFDM symbol #2

… … …

data carrier

pilot carrier

July 2007


doc.: IEEE 802.15-07-0766-00-003c

Submission

1/2BPSK187.5 MbpsLRT1

2/3BPSK250 MbpsLRT2

1/2QPSK375 MbpsLRT3

2/3

Convolutional

Code + RS,

LDPC,

Turbo Codes

[TBD]

QPSK500 MHz

(incl. guard

band)

500 MbpsLRT4

OFDM

mode

1/216-QAM750 MbpsLRT5




2/3BPSK1000 MbpsLRT15

1/2BPSK2 GHz

(incl. guard

band)

750 MbpsLRT14

1/2QPSK1500 MbpsLRT16




2/3BPSK500 MbpsLRT10

1/2BPSK

1 GHz

(incl. guard

band)

375 MbpsLRT9

PHY ModeTransmission

Mode

PHY-SAP data

rateBandwidth Modulation Coding Code Rate

OFDM LRT Modes (up to 2 Gbps)

July 2007


doc.: IEEE 802.15-07-0766-00-003c

Submission

OFDM MRT Modes (from 2 to 3 Gbps)

2/3

Convolutional

Code + RS,

LDPC,

Turbo Codes

[TBD]

16-QAM1 GHz

(incl. guard

band)

2000 MbpsMRT1

OFDM

mode

5/616-QAM2500 MbpsMRT2


2/3QPSK2 GHz

(incl. guard

band)

2000 MbpsMRT4



ModePHY-SAP data


July 2007


doc.: IEEE 802.15-07-0766-00-003c

Submission

OFDM HRT Modes (over 3 Gbps)

2/3Convolutional

Code + RS,

LDPC,

Turbo Codes

[TBD]

16-QAM

2 GHz

(incl. guard

band)

4000 MbpsHRT1

OFDM

mode

5/616-QAM5000 MbpsHRT2

2/364-QAM6000 MbpsHRT3


ModePHY-SAP data


July 2007


doc.: IEEE 802.15-07-0766-00-003c

Submission

Conclusion

• In order to meet the requirements for different applications (file transfer, video streaming…), a dual PHY with both SC and OFDM modes is desirable

• This proposal describes the baseband design for an OFDM mode allowing 60 GHz transmission at data rates from 187 Mbps to 6 Gbps

• A scalable baseband design is proposed, allowing for transmission over 500 MHz, 1 GHz and 2 GHz wide channels

• We presented advanced techniques increasing the system efficiencyand robustness

• We are open to discussions with any companies interested in OFDM and encourage exchanges to further improve the definition of the TG3c OFDM modes

July 2007


doc.: IEEE 802.15-07-0766-00-003c

Submission

Thank you !

Questions ?

[email protected]

[email protected]

[email protected]

july 2007 doc.: ieee 802.15-07-0766-00-003c project: ieee ......mrt1 2000 mbps ofdm mode mrt2 2500...

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