1. July 12, 2000
doc.: IEEE <00210>
March 2001
Project: IEEE P802.11b Working Group for Wireless Local Area Networks (WLANs)
Submission Title: [Summary of SG Proposal to TGg]
Date Submitted: [ 12 March 2001 ]
Source: [ T. O’Farrell, L.E. Aguado & C. Caldwell] Company [Supergold Communication Ltd. ]
Address [ 2-3 Sandyford Village, Sandyford, Dublin 18, Ireland ]
Voice:[ ], FAX: [ ], [ ]
Re: [ Physical layer modulation proposal for the Higher Rate Extension to b Standard]
Abstract: [ This contribution is a summary presentation of Supergold’s MBCK proposal for the Higher Rate Extension to b Standard]
Purpose: [ Proposal for the Higher Rate Extension to b Standard]
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
O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.
<author>, <company>

2. Outline of the Presentation
July 12, 2000
doc.: IEEE <00210>
March 2001
Outline of the Presentation
Comparison Criteria
Performance Evaluation
MBCK Attributes
Soft Decision Decoding
Conclusions
O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.
<author>, <company>

3. Comparison Criteria MBCK Performance with an DFE equaliser
July 12, 2000
doc.: IEEE <00210>
March 2001
Comparison Criteria
The following new results have been included in documents 336r48G and 1017r28G
MBCK Performance with an DFE equaliser
Timing off-set performance
Jamming test completed for PER=10-2
O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.
<author>, <company>

4. Comparison Criteria – Cont.
July 12, 2000
doc.: IEEE <00210>
March 2001
Comparison Criteria – Cont.
Anomalies addressed
PA back-off figures
ISI only multipath performance at 25 ns rms delay spread
O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.
<author>, <company>

5. Performance Evaluation
March 2001
Performance Evaluation
Note: performance of reference systems from IEEE /064r1, “Comparison of g Proposals”
PER vs Eb/No (1000B)
O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.

6. Performance Evaluation
March 2001
Performance Evaluation
Note: performance of reference systems from IEEE /064r1, “Comparison of g Proposals”
PER vs SNR (1000B)
O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.

7. Performance Evaluation
March 2001
Performance Evaluation
Note: performance of reference systems from IEEE /064r1, “Comparison of g Proposals”
PER vs SNR (1000B)
O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.

8. M-ary Bi-Code Keying Inner MBCK 64 state quaternary block code
March 2001
M-ary Bi-Code Keying
Supergold’s solution is a concatenated coding scheme consisting of:
Inner MBCK 64 state quaternary block code
Maps to 16 QAM constellation and spans 4 symbols.
Outer Reed Solomon (63,k) code
k=41 for 22 Mb/s and k=57 for 30 Mb/s
O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.

9. MBCK-RS Encoding Chain
July 12, 2000
doc.: IEEE <00210>
March 2001
MBCK-RS Encoding Chain
32-Correlator Bank
Greatest
Peak Detector
RS Decoder 6 1
Rx I IN
Rx Q IN rI rQ c’
DATA OUT y
64-ary Bi-Code Keying
Select 1 of 64 Sequences
RS Encoder
DATA IN d c xI xQ 8
I OUT
Q OUT
32 Sequences +
Complements
O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.
<author>, <company>

10. March 2001
MBCK Attributes
Thorough evaluation of MBCK according to the comparison criteria completed: (ref. 336r48G and 1017r28G).
Good coding gain
PA non-linearity effects are constrained for back-offs > 4 dB
MBCK waveform ameanable to equalisation by all the key equalisation techniques
O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.

11. MBCK Attributes - Cont Supports 22 and 30 Mb/s modes
March 2001
MBCK Attributes - Cont
Supports 22 and 30 Mb/s modes
Tolerant to 10% rms timing jitter
Tolerant to 4o rms phase noise
O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.

12. March 2001
MBCK Attributes - Cont
MBCK is a robust coding scheme that meets the TGg comparision criteria
Low complexity code (7 kgates for MBCK and 7 kgates for Reed Solomon Code)
Works with the same radio as b
Low cost solution
Readily implementable giving short time to market (RTL code for MBCK available)
O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.

13. Soft Decision Decoding with MBCK
March 2001
Soft Decision Decoding with MBCK
A soft metric can be readily obtained from the MBCK signal set using common symbol-to-bit mapping techniques
Allows the use of binary convolutional codes (bcc) with MBCK; two codes investigated
Rate 2/3 Punctured [ ] – p133171
Rate 2/3 bcc (64 state trellis code)
O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.

14. Soft Decision Decoding with MBCK
March 2001
Soft Decision Decoding with MBCK
Rate 2/3 code supports 22 and 29 Mb/s rates
22 Mb/s mode uses 64-ary BCK
29 Mb/s mode uses 256-ary BCK
Both MBCK codes span 4 symbols
No change in clocks, radio or baseband processor.
O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.

15. Soft Decision Decoding with MBCK
March 2001
Soft Decision Decoding with MBCK
BER vs. Eb/N0 in the AWGN for bcc
O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.

16. Soft Decision & MBCK – 22 Mb/s
March 2001
Soft Decision & MBCK – 22 Mb/s
BER vs. SNR for MBCK in the AWGN for p and bcc
(100 B/Pk)
BER vs. SNR for MBCK in the AWGN for p and bcc
(100 B/Pk)
O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.

17. Soft Decision & MBCK – 29 Mb/s
March 2001
Soft Decision & MBCK – 29 Mb/s
BER vs. SNR for MBCK in the AWGN for p and bcc
(100 B/Pk)
O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.

18. Soft Decision & MBCK – Summary
March 2001
Soft Decision & MBCK – Summary
22 Mb/s mode gives 1.25 dB coding gain over RS at 10-2 PER
29 Mb/s mode gives 2.25 dB coding gain over RS at 10-2 PER
64 state code offers enhanced PER performance for reasonable complexity
O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.

19. MBCK-BCC Encoding Chain
March 2001
MBCK-BCC Encoding Chain 1
DATA IN xI 8
I OUT 1 6
Select 1 of 64 Sequences d
BCC Encoder c xQ 1
Q OUT
32 Sequences +
Complements rI 1
Rx I IN
Soft Decision Metric 1 c’ 6
Viterbi Decoder y rQ 1
Rx Q IN
DATA OUT
M-ary Bi-Code Keying
O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.

20. 8-ary BCK Example using Length 4 Quanternary Codes
March 2001
8-ary BCK Example using Length 4 Quanternary Codes
Quaternary
Code LUT
I/Q Tx Waveform
I&D
Greatest Peak Detector & Sign
20 -20
0 0
0 0 0
0 0 1
0 1 0
0 1 1
1 0 0
1 0 1
1 1 0
1 1 1
Data
LUT
Tx Function
Rx Function
O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.

21. Conclusions MBCK is a low complexity code that
March 2001
Conclusions
MBCK is a low complexity code that
Meets the WLAN robustness criteria
Is a mature concept based on MBOK
Uses same radio as b
Can be used with all equaliser types
Can use Hard & Soft Decision FEC
Is an inexpensive solution for WLANs
A road map exists to achieve even higher data rates with MBCK
O'Farrell, Aguado & Caldwell, Supergold Comm. Ltd.