[Sls-ngu] Re: Update to NGU Greenbook

[Kazz, Greg J (313B)]

Tomaso,

Here is an explanation of the complexity column given to me by Ken Andrews, which I will factor into the text in abreviated form:

The "Memory" column gives the number of kilobits of storage required to decode the listed code.  For example, a BCH decoder in SEC mode requires only a 6-bit shift register, and so its memory is listed as 0.006 kbits.  At the other extreme, the (128,64) LDPC code requires about two bytes per graph edge (512 edges x 2 x 8 = 8192 bits) plus some memory per channel symbol, for a total of about 8.2 kbits.  Unfortunately, these complexity metrics depend on details of the implementation, so different decoders will vary somewhat.  However, these numbers give a good sense of the complexity landscape, and are useful for comparison.

Regards,

Greg

From: "Tomaso.deCola at dlr.de<mailto:Tomaso.deCola at dlr.de>" <Tomaso.deCola at dlr.de<mailto:Tomaso.deCola at dlr.de>>
Date: Tuesday, September 11, 2012 7:51 AM
To: "Kazz, Greg J (313B)" <greg.j.kazz at jpl.nasa.gov<mailto:greg.j.kazz at jpl.nasa.gov>>
Cc: "Gianluigi.Liva at dlr.de<mailto:Gianluigi.Liva at dlr.de>" <Gianluigi.Liva at dlr.de<mailto:Gianluigi.Liva at dlr.de>>, "sls-ngu at mailman.ccsds.org<mailto:sls-ngu at mailman.ccsds.org>" <sls-ngu at mailman.ccsds.org<mailto:sls-ngu at mailman.ccsds.org>>
Subject: RE: Update to NGU Greenbook

Greg,

Please find attached the new version with inputs from DLR. Please note that most of contributions concern the coding part; there are also some comments on part of the text that can be improved in our opinion. In particular Table 5-1 is not editable and some explanation on the column complexity_memory should be given.

Unless other comments are expected, this document version could be used as baseline for the discussion during the meeting in Cleveland

Best Regards,

Tomaso

————————————————————————
Deutsches Zentrum für Luft- und Raumfahrt (DLR)
German Aerospace Center
Institute of Communications und Navigation | Satellite Networks | Oberpfaffenhofen | 82234 Wessling | Germany
Tomaso de Cola, Ph.D.
Telefon +49 8153 28-2156 | Telefax  +49 8153 28-2844 |tomaso.decola at dlr.de<mailto:sandro.scalise at dlr.de>
http://www.dlr.de/kn/institut/abteilungen/san
From: Kazz, Greg J (313B) [mailto:greg.j.kazz at jpl.nasa.gov]
Sent: Wednesday, July 25, 2012 8:13 PM
To: Cola, Tomaso de
Cc: Liva, Gianluigi; sls-ngu at mailman.ccsds.org<mailto:sls-ngu at mailman.ccsds.org>
Subject: Re: Update to NGU Greenbook

Tomaso,

I've transferred the word version now to the same directory that the pdf file is in.
Thanks in advance for your contribution to the NGU Greenbook !

Easily accessed via this URL below:

http://tiny.cc/9rk0hw

Best regards,

Greg

From: "Tomaso.deCola at dlr.de<mailto:Tomaso.deCola at dlr.de>" <Tomaso.deCola at dlr.de<mailto:Tomaso.deCola at dlr.de>>
Date: Wednesday, July 25, 2012 12:45 AM
To: "Kazz, Greg J (313B)" <greg.j.kazz at jpl.nasa.gov<mailto:greg.j.kazz at jpl.nasa.gov>>
Cc: "Gianluigi.Liva at dlr.de<mailto:Gianluigi.Liva at dlr.de>" <Gianluigi.Liva at dlr.de<mailto:Gianluigi.Liva at dlr.de>>, "sls-ngu at mailman.ccsds.org<mailto:sls-ngu at mailman.ccsds.org>" <sls-ngu at mailman.ccsds.org<mailto:sls-ngu at mailman.ccsds.org>>
Subject: RE: Update to NGU Greenbook

Greg,

Could you please also upload a word version of the document so that we can update it with details about the codes we presented in the last two CCSDS meetings, as recently agreed?

Thanks in advance

Tomaso

————————————————————————
Deutsches Zentrum für Luft- und Raumfahrt (DLR)
German Aerospace Center
Institute of Communications und Navigation | Satellite Networks | Oberpfaffenhofen | 82234 Wessling | Germany
Tomaso de Cola, Ph.D.
Telefon +49 8153 28-2156 | Telefax  +49 8153 28-2844 |tomaso.decola at dlr.de<mailto:sandro.scalise at dlr.de>
http://www.dlr.de/kn/institut/abteilungen/san
From:sls-ngu-bounces at mailman.ccsds.org<mailto:sls-ngu-bounces at mailman.ccsds.org> [mailto:sls-ngu-bounces at mailman.ccsds.org] On Behalf Of Kazz, Greg J (313B)
Sent: Tuesday, July 03, 2012 1:35 AM
To: sls-ngu at mailman.ccsds.org<mailto:sls-ngu at mailman.ccsds.org>; Massimo.Bertinelli at esa.int<mailto:Massimo.Bertinelli at esa.int>
Subject: [Sls-ngu] Update to NGU Greenbook

NGU WG members,

Please find the latest update to the NGU WG Green book dated July 5 (in advance of the US 4th of July holiday) on the CWE under the URL:
http://tiny.cc/13dugw

The purpose of this update is to address the ESA concerns documented in the viewgraph package (also loaded – same URL above) which we did not have time to discuss during the meeting in Darmstadt.  I believe I was able to resolve most of the ESA issues by making changes to the green book.  Changes are shown in red using the Word revision feature so that they are easily found.

Issues that did not require rewording but rather clarification outside of the document are:

Chapter 4 – FECF presence not required for LDPC codes.
Chapter 4.2 – ARQ sent via telemetry. It is envisioned that LTP will provide another alternative (selective repeat) along with COP-1 (go-back-N) for TC.
Table 5.1 – How is convolutional code evaluated wrt CWER – I asked the coding group to comment on this one – waiting on response now.

Your comments are as always welcome.

Best regards,

Greg Kazz
Chairman SLS-NGU WG

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