1. Submission Title: [FEC and modulations options and proposal for TG4a ]
Sept 2005
Project: IEEE P Working Group for Wireless Personal Area Networks (WPANs)
Submission Title: [FEC and modulations options and proposal for TG4a ]
Date Submitted: [30-Sep-2005]
Source: [Laurent Ouvry, Samuel Dubouloz]
Company [CEA-Leti]
Address [17 rue des Martyrs Grenoble]
Voice:[ ], FAX: [ ],
E−Mail:
Re: [ a.]
Abstract: [Gives the current FEC and modulation proposals for TG4a]
Purpose: [To promote discussion in a.]
Notice: This document has been prepared to assist the IEEE P 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 P
L. Ouvry, S. Dubouloz, CEA-Leti

2. Outline Reference documents Baseline What we propose Simulations
Sept 2005
Outline
Reference documents
Baseline
What we propose
Simulations
L. Ouvry, S. Dubouloz, CEA-Leti

3. Reference documents to build this one
Sept 2005
Reference documents to build this one
IEEE XXX-0Y-004a
XXXrY (…)
424r1 (simulation framework)
389r2 (band plan)
456r1 and 456r2 (preamble)
466r0 (amendment to the preamble)
428r0 (PRF and peak power)
528r0 (modulation and scrambler structure)
600r0 (FEC options and their numbering !)
L. Ouvry, S. Dubouloz, CEA-Leti

4. Sept 2005
Modulation(from 582r0)
L. Ouvry, S. Dubouloz, CEA-Leti

5. Scrambler example (from 582r0)
Sept 2005
Scrambler example (from 582r0)
L. Ouvry, S. Dubouloz, CEA-Leti

6. Modulation : bursts and peak PRF
<month year>
doc.: IEEE <doc#>
Sept 2005
Modulation : bursts and peak PRF
symbol duration ~ 1.0us = 512 chips = 64 TB (FEC 5 option)
1 chip ~ 2 ns
S =
burst duration = TB
= 8 chips ~ 16 ns S =
Proposed peak PRF of 494 MHz, with S code of length 8 (TBC)
S code duration = 8 / peak PRF ~ 16 ns
Chip duration is 1/peak PRF
L. Ouvry, S. Dubouloz, CEA-Leti
<author>, <company>

7. Modulation : base is FEC 5 see slide 12 or 600r0
<month year>
doc.: IEEE <doc#>
Sept 2005
COH.
NON COH. 00
0 - 01 10
1 - 11
Modulation : base is FEC 5 see slide 12 or 600r0
PPM bit (seen by coherent and non coherent receiver)
BPSK bit (seen by coherent receiver only) S 1 31 32 33 63 15 16 47 48 -S 1 31 32 33 63 15 16 47 48 S 1 31 32 33 63 15 16 47 48 -S 1 31 32 33 63 15 16 47 48
symbol duration ~ 1.0us = 64 TB (FEC 5 option)
PPI = 32 bursts = 512ns
burst
L. Ouvry, S. Dubouloz, CEA-Leti
<author>, <company>

8. doc.: IEEE 802.15-<doc#>
<month year>
doc.: IEEE <doc#>
Sept 2005
COH.
NON COH. 00
0 - 01 10
1 - 11
Scrambling (TBC)
possible positions obtained through scrambling
Guard time for channel delay spread (260ns) S S 1 31 32 33 63 15 16 47 48 -S -S 1 31 32 33 63 15 16 47 48 S S 1 31 32 33 63 15 16 47 48 -S -S 1 31 32 33 63 15 16 47 48
Remark : S value is also changed at each symbol
L. Ouvry, S. Dubouloz, CEA-Leti
<author>, <company>

9. doc.: IEEE 802.15-<doc#>
<month year>
doc.: IEEE <doc#>
Sept 2005
Proposal 6 : 4-PPM + BPSK
Guard time for channel delay spread (130ns) C NC
000
00 -
001
010
01 -
011
110
11 -
111
100
10 -
101 S 31 32 63 7 16 39 40 8 15 24 23 47 48 56 57 -S 31 32 63 7 16 39 40 8 15 24 23 47 48 56 57 S 31 32 63 7 16 39 40 8 15 24 23 47 48 56 57 -S 31 32 63 7 16 39 40 8 15 24 23 47 48 56 57 S 31 32 63 7 16 39 40 8 15 24 23 47 48 56 57 -S 31 32 63 7 16 39 40 8 15 24 23 47 48 56 57 S 31 32 63 7 16 39 40 8 15 24 23 47 48 56 57 -S 31 32 63 7 16 39 40 8 15 24 23 47 48 56 57
L. Ouvry, S. Dubouloz, CEA-Leti
<author>, <company>

10. doc.: IEEE 802.15-<doc#>
<month year>
doc.: IEEE <doc#>
Sept 2005
Proposal 6 : 4-PPM + BPSK C NC
000
00 -
001
010
01 -
011
110
11 -
111
100
10 -
101
PPM bits (seen by both receivers) S -S 31 32 63 7 16 39 40 8 15 24 23 47 48 56 57
BPSK bit (seen by coherent receiver only)
L. Ouvry, S. Dubouloz, CEA-Leti
<author>, <company>

11. doc.: IEEE 802.15-<doc#>
<month year>
doc.: IEEE <doc#>
Sept 2005
FEC 6 Details
Viterbi
1/2
Common Rb at PHY SAP +
Coder + Modulation Mapping
Non Coherent Receiver
(only 4-PPM)
Convolutional
1/3
Non Coherent Receiver
(4-PPM + Polarity)
Viterbi
1/3
L. Ouvry, S. Dubouloz, CEA-Leti
<author>, <company>

12. Convolutional Encoder
Sept 2005
FEC Options (from 600r0)
SOC code
K= 3,4 or 5
R = 1/4
Coherent Receiver: True Rate = ¼
Non Coherent Receiver: Equivalent to Rate = ½
(Rate ¼ with erasures)
FEC 1
Convolutional Encoder
K= 3,4 or 5
R= 1/4
Coherent Receiver: True Rate = ¼
Non Coherent Receiver: Equivalent to Rate = ½
(Rate ¼ with erasures)
FEC 2
Systematic
Convolutional
Encoder
K= 3,4 or 5
R = 1/2
Convolutional
Encoder
K=3, R= 1/2
FEC 3
Coherent Receiver: Concatenated code, Rate = ¼
Non Coherent Receiver: Convolutional code, Rate = ½
Systematic
Convolutional
Encoder
K= 3,4 or 5
R = 1/2
BCH or RS
GF(28): RS(40,32)
GF(26): RS(53,43)
Coherent Receiver: Concatenated code Rate = 0.4
Non Coherent Receiver: RS code, Rate = 0.8
FEC 4
Systematic Convolutional Encoder
K= 3,4 or 5
R= 1/2
FEC 5
Coherent Receiver: Convolutional code Rate = ½
Non Coherent Receiver: Uncoded
Convolutional Encoder
K= 3,4 or 5
R= 1/3
Coherent Receiver: Convolutional code Rate = 1/3
Non Coherent Receiver: Convolutional code Rate = 1/2
FEC 6
L. Ouvry, S. Dubouloz, CEA-Leti

13. So what we propose in FEC 6 is:
Sept 2005
So what we propose in FEC 6 is:
Coherent
Non-Coherent Tx
(Common for Coherent and Non Coherent)
Symbol Time
~1µs
PHY-SAP
~1 Mbps
FEC 6
Convolutional 1/3
Modulation
4-PPM + Polarity
(3 bits per symbol)
Channel
Raw Rate
3 Mbps Rx
Demodulation
4PPM + Polarity
(3 bits/symbol)
4PPM only
(2 bits/symbol)
Decoder
Viterbi 1/3
Viterbi 1/2
~1Mbps
 Perfect compatibility between Tx and coherent and
non-coherent Rx
L. Ouvry, S. Dubouloz, CEA-Leti

14. Summary of rates (modifed from 600r0)
Sept 2005
Summary of rates (modifed from 600r0)
Options we intend to simulate and compare
L. Ouvry, S. Dubouloz, CEA-Leti

15. Simulations under work
Sept 2005
Simulations under work
Options 3, 5 and 6 :
For coherent and non coherent
With soft and hard decisions
With K=3 and 5
Then with :
Scrambling and peak PRFs of 494 & 247 MHz
Checking of spectrum compliance with FCC (thanks to a-UWB-Power-Measurements.zip)
L. Ouvry, S. Dubouloz, CEA-Leti