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ISO 22642:2015

(Main)

Space data and information transfer systems — TC synchronization and channel coding

Space data and information transfer systems — TC synchronization and channel coding

ISO 22642:2015 defines synchronization and channel coding schemes in terms of: a) the services provided to the users of this specification; b) data formats; and c) the procedures performed to generate and process the data formats. It does not specify: a) individual implementations or products; b) the methods or technologies required to perform the procedures; or c) the management activities required to configure and control the system.

Systèmes de transfert des données et informations spatiales — Synchronisation TC et codage de canal

General Information

Status
Published
Publication Date
15-Nov-2015
ICS
49.140 - Space systems and operations
Technical Committee
ISO/TC 20/SC 13 - Space data and information transfer systems
Drafting Committee
ISO/TC 20/SC 13 - Space data and information transfer systems
Current Stage
9093 - International Standard confirmed
Start Date
14-Nov-2023
Completion Date
19-Apr-2025
Ref Project

Relations

Revises
ISO 22642:2005 - Space data and information transfer systems — TC (telecommand) synchronization and channel coding
Effective Date
06-Jul-2012
ISO 22642:2015 - Space data and information transfer systems -- TC synchronization and channel codingISO 22642:2015 - Space data and information transfer systems -- TC synchronization and channel coding
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ISO 22642:2015 - Space data and information transfer systems -- TC synchronization and channel coding
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INTERNATIONAL ISO
STANDARD 22642
Second edition
2015-11-15
Space data and information transfer
systems — TC synchronization and
channel coding
Systèmes de transfert des données et informations spatiales —
Synchronisation TC et codage de canal

Reference number
©
ISO 2015
©  ISO 2015
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any
means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission.
Permission can be requested from either ISO at the address below or ISO’s member body in the country of the requester.
ISO copyright office
Case postale 56  CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Published in Switzerland
ii © ISO 2015 – All rights reserved

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
This International Standard cancels and replaces ISO 22642:2005 which has been technically revised. It also
incorporates ISO 22642:2005/Cor.1:1997.
ISO 22642 was prepared by the Consultative Committee for Space Data Systems (CCSDS) (as CCSDS
231.0-B-2, September 2010) and was adopted (without modifications except those stated in clause 2 of this

International Standard) by Technical Committee ISO/TC 20, Aircraft and space vehicles, Subcommittee
SC 13, Space data and information transfer systems.

Recommendation for Space Data System Standards
TC SYNCHRONIZATION
AND CHANNEL CODING
RECOMMENDED STANDARD
CCSDS 231.0-B-2
BLUE BOOK
September 2010
AUTHORITY
Issue: Recommended Standard, Issue 2
Date: September 2010
Location:
This document has been approved for publication by the Management Council of the
Consultative Committee for Space Data Systems (CCSDS) and represents the consensus
technical agreement of the participating CCSDS Member Agencies. The procedure for
review and authorization of CCSDS documents is detailed in the Procedures Manual for the
Consultative Committee for Space Data Systems, and the record of Agency participation in
the authorization of this document can be obtained from the CCSDS Secretariat at the
address below.
This document is published and maintained by:

CCSDS Secretariat
Space Communications and Navigation Office, 7L70
Space Operations Mission Directorate
NASA Headquarters
Washington, DC 20546-0001, USA
STATEMENT OF INTENT
The Consultative Committee for Space Data Systems (CCSDS) is an organization officially
established by the management of its members. The Committee meets periodically to address
data systems problems that are common to all participants, and to formulate sound technical
solutions to these problems. Inasmuch as participation in the CCSDS is completely
voluntary, the results of Committee actions are termed Recommended Standards and are
not considered binding on any Agency.
This Recommended Standard is issued by, and represents the consensus of, the CCSDS
members. Endorsement of this Recommendation is entirely voluntary. Endorsement,
however, indicates the following understandings:
o Whenever a member establishes a CCSDS-related standard, this standard will be in
accord with the relevant Recommended Standard. Establishing such a standard
does not preclude other provisions which a member may develop.
o Whenever a member establishes a CCSDS-related standard, that member will
provide other CCSDS members with the following information:
-- The standard itself.
-- The anticipated date of initial operational capability.
-- The anticipated duration of operational service.
o Specific service arrangements shall be made via memoranda of agreement. Neither
this Recommended Standard nor any ensuing standard is a substitute for a
memorandum of agreement.
No later than five years from its date of issuance, this Recommended Standard will be
reviewed by the CCSDS to determine whether it should: (1) remain in effect without change;
(2) be changed to reflect the impact of new technologies, new requirements, or new
directions; or (3) be retired or canceled.
In those instances when a new version of a Recommended Standard is issued, existing
CCSDS-related member standards and implementations are not negated or deemed to be
non-CCSDS compatible. It is the responsibility of each member to determine when such
standards or implementations are to be modified. Each member is, however, strongly
encouraged to direct planning for its new standards and implementations towards the later
version of the Recommended Standard.
FOREWORD
This document is a technical Recommended Standard for use in developing synchronization
and channel coding systems and has been prepared by the Consultative Committee for Space
Data Systems (CCSDS). The synchronization and channel coding concept described herein
is intended for missions that are cross-supported between Agencies of the CCSDS.
This Recommended Standard establishes a common framework and provides a common
basis for the synchronization and channel coding schemes to be used by space missions with
the TC Space Data Link Protocol (reference [1]) over ground-to-space and space-to-space
communications links. This Recommended Standard was developed from an older CCSDS
Recommended Standard (reference [C2]), which defines essentially the same schemes but in
a slightly different context.
This Recommended Standard does not change the major technical content defined in
reference [C2], but the presentation of the specification has been changed so that:
a) these schemes can be used to transfer any data over any space link in either direction;
b) all CCSDS space link protocols are specified in a unified manner;
c) the layered model matches the Open Systems Interconnection (OSI) Basic Reference
Model (reference [2]).
Together with the change in presentation, a few technical specifications in reference [C2]
have been changed in order to define all Space Data Link Protocols in a unified way. Also,
some technical terms in reference [C2] have been changed in order to unify the terminology
used in all the CCSDS Recommended Standards that define space link protocols and to
define these schemes as general communications schemes. These changes are listed in
annex D of this Recommended Standard.
Through the process of normal evolution, it is expected that expansion, deletion, or
modification of this document may occur. This Recommended Standard is therefore subject
to CCSDS document management and change control procedures, which are defined in the
Procedures Manual for the Consultative Committee for Space Data Systems. Current
versions of CCSDS documents are maintained at the CCSDS Web site:
http://www.ccsds.org/
Questions relating to the contents or status of this document should be addressed to the
CCSDS Secretariat at the address indicated on page i.
At time of publication, the active Member and Observer Agencies of the CCSDS were:
Member Agencies
– Agenzia Spaziale Italiana (ASI)/Italy.
– Canadian Space Agency (CSA)/Canada.
– Centre National d’Etudes Spatiales (CNES)/France.
– China National Space Administration (CNSA)/People’s Republic of China.
– Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR)/Germany.
– European Space Agency (ESA)/Europe.
– Instituto Nacional de Pesquisas Espaciais (INPE)/Brazil.
– Japan Aerospace Exploration Agency (JAXA)/Japan.
– National Aeronautics and Space Administration (NASA)/USA.
– Russian Federal Space Agency (RFSA)/Russian Federation.
– UK Space Agency/United Kingdom.
Observer Agencies
– Austrian Space Agency (ASA)/Austria.
– Belgian Federal Science Policy Office (BFSPO)/Belgium.
– Central Research Institute of Machine Building (TsNIIMash)/Russian Federation.
– China Satellite Launch and Tracking Control General, Beijing Institute of Tracking
and Telecommunications Technology (CLTC/BITTT)/China.
– Chinese Academy of Sciences (CAS)/China.
– Chinese Academy of Space Technology (CAST)/China.
– Commonwealth Scientific and Industrial Research Organization (CSIRO)/Australia.
– CSIR Satellite Applications Centre (CSIR)/Republic of South Africa.
– Danish National Space Center (DNSC)/Denmark.
– Departamento de Ciência e Tecnologia Aeroespacial (DCTA)/Brazil.
– European Organization for the Exploitation of Meteorological Satellites
(EUMETSAT)/Europe.
– European Telecommunications Satellite Organization (EUTELSAT)/Europe.
– Geo-Informatics and Space Technology Development Agency (GISTDA)/Thailand.
– Hellenic National Space Committee (HNSC)/Greece.
– Indian Space Research Organization (ISRO)/India.
– Institute of Space Research (IKI)/Russian Federation.
– KFKI Research Institute for Particle & Nuclear Physics (KFKI)/Hungary.
– Korea Aerospace Research Institute (KARI)/Korea.
– Ministry of Communications (MOC)/Israel.
– National Institute of Information and Communications Technology (NICT)/Japan.
– National Oceanic and Atmospheric Administration (NOAA)/USA.
– National Space Agency of the Republic of Kazakhstan (NSARK)/Kazakhstan.
– National Space Organization (NSPO)/Chinese Taipei.
– Naval Center for Space Technology (NCST)/USA.
– Scientific and Technological Research Council of Turkey (TUBITAK)/Turkey.
– Space and Upper Atmosphere Research Commission (SUPARCO)/Pakistan.
– Swedish Space Corporation (SSC)/Sweden.
– United States Geological Survey (USGS)/USA.
DOCUMENT CONTROL
Document Title Date Status
CCSDS TC Synchronization and Channel September Original Issue
231.0-B-1 Coding, Issue 1 2003
CCSDS TC Synchronization and Channel September Current issue:
231.0-B-2 Coding, Recommended Standard, 2010 – adds an option for
Issue 2 repeated
transmissions of
Transfer Frames
(note).
NOTE – Substantive changes from the previous issue are indicated by change bars in the
inside margin.
CONTENTS
Section Page
1  INTRODUCTION . 1-1

1.1  PURPOSE . 1-1
1.2  SCOPE . 1-1
1.3  APPLICABILITY . 1-1
1.4  RATIONALE . 1-2
1.5  DOCUMENT STRUCTURE . 1-2
1.6  CONVENTIONS AND DEFINITIONS. 1-2
1.7  REFERENCES . 1-5

2  OVERVIEW . 2-1

2.1  ARCHITECTURE . 2-1
2.2  SUMMARY OF FUNCTIONS . 2-1
2.3  INTERNAL ORGANIZATION OF SUBLAYER . 2-3

3  BCH CODING . 3-1

3.1  INTRODUCTION . 3-1
3.2  CODEBLOCK FORMAT . 3-1
3.3  ENCODING PROCEDURE . 3-1
3.4  FILL DATA . 3-2
3.5  DECODING PROCEDURE . 3-3

4.1  INTRODUCTION . 4-1
4.2  CLTU UNIT FORMAT . 4-1
4.3  CLTU RECEPTION LOGIC . 4-2

5  RANDOMIZER . 5-1

5.1  INTRODUCTION . 5-1
5.2  RANDOMIZER DESCRIPTION . 5
...

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