1

Montreal – Spring 2004

SPACE LINK SERVICES CODING AND SYNCHRONIZATION WORKING GROUP

SLS-C&S WG

Spring 2004 MeetingSummary to SLS Area Director

2

Montreal – Spring 2004

SPACE LINK SERVICES CODING AND SYNCHRONIZATION WORKING GROUP

SLS-C&S WG summary

• Problems report:– Missing consensus.

• Future work/charter:– Future work will continue as BOF. Charter to be produced.

• See further for details.

3

Montreal – Spring 2004

SPACE LINK SERVICES CODING AND SYNCHRONIZATION WORKING GROUP

Discussed Topics (1/3)

• Serial Concatenated Convolutional Codes for 8PSK (ESA/ESTEC/Polito)– Proposal currently ongoing in RFM;

informative for C&S. Possible future options together with new modulation schemes.

• Complexity Comparison of Coding Schemes (ESA/ESTEC/Polito)

4

Montreal – Spring 2004

SPACE LINK SERVICES CODING AND SYNCHRONIZATION WORKING GROUP

Discussed Topics (2/3)

• Requirements, Benchmarking & Overview of Proposed LDPCC (ESA/ESOC/UniBO)– Initial proposal to be discussed and refined with

WG Members.• Generalized IRA LDPCC

(ESA/ESOC/UniBO)– Further possibility for refining LDPCC

selection.

5

Montreal – Spring 2004

SPACE LINK SERVICES CODING AND SYNCHRONIZATION WORKING GROUP

Discussed Topics (3/3)

• Orange Book Progress & Considerations on Requirements (NASA/GSFC)

• JPL Proposal for LDPCC (NASA/JPL)• CNES proposal supporting DVB-S2

adoption (CNES)

6

Montreal – Spring 2004

SPACE LINK SERVICES CODING AND SYNCHRONIZATION WORKING GROUP

Problem & Way Out (Hopefully)

• Three Different proposals tabled– NASA/GSFC Quasi-Cyclic LDPCC– NASA/JPL Protograph LDPCC– CNES support to DVB-S2

NO CONSENSUS• WG not justified any more• Migration to BOF or complete stop?

7

Montreal – Spring 2004

SPACE LINK SERVICES CODING AND SYNCHRONIZATION WORKING GROUP

Migration to BOF or complete stop?• Member Agencies recognize the difficult

status without consensus and take proactive approach.

• Principle agreement for a set of “agreeable” codes reached.

• Codes shall be evaluated by BOF work and eventually generate consensus proposal for WG.

• Resolution: Convert WG to BOF.

8

Montreal – Spring 2004

SPACE LINK SERVICES CODING AND SYNCHRONIZATION WORKING GROUP

Agreed Set

• Rate ½ Code to be derived by JPL proposal• Rate 7/8 Code to be derived by GSFC

proposal C2• Rates 2/3, ¾ and 5/6 Quasi-Cyclic Codes to

be proposed by GSFC

• All codes to be validated by BOF taking as reference DVB-S2 characteristics.

9

Montreal – Spring 2004

SPACE LINK SERVICES CODING AND SYNCHRONIZATION WORKING GROUP

Objectives of BOF1. Identify a set of mandatory/desirable

requirements (addressing also interaction with modulation).

2. Define a Benchmark Matrix for evaluation of proposed codes wrt identified req’s.

3. Identify a set of Quasi-Cyclic LDPCC for frames of (approx) 8 & 16k bits (des.32k).

4. Select the proposed codes by proper benchmarking.

10

Montreal – Spring 2004

SPACE LINK SERVICES CODING AND SYNCHRONIZATION WORKING GROUP

Schedule of BOF1. Identify requirements.2. Define a Benchmark Matrix.

By Fall 20043. Identify a set of Quasi-Cyclic LDPCC for

frames of (approx) 8 & 16k bits (des.32k).4. Select the proposed codes by proper

benchmarking.By Spring 2005 (Initial results)By Fall 2005 (Finalized results)

11

Montreal – Spring 2004

SPACE LINK SERVICES CODING AND SYNCHRONIZATION WORKING GROUP

One task for the WG?

• The Orange Book Task is not dropped.• Shall it continue as (only) task of the WG

while the code selection is moved to the newly created BOF?