ISO 11754:2003

Space data and information transfer systems — Telemetry channel coding

ISO 11754:2003 specifies the requirements for telemetry channel coding of space data and information transfer systems used in civil space applications.

Systèmes de transfert des informations et données spatiales — Codage de canal pour télémesure

General Information

• Status: Withdrawn
• Publication Date: 11-Feb-2003
• Withdrawal Date: 11-Feb-2003
• 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: 9599 - Withdrawal of International Standard
• Completion Date: 02-Mar-2007

Relations

• Revises: ISO 11754:1994 - Space data and information transfer systems — Telemetry channel coding
• Effective Date: 15-Apr-2008

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 11754
Second edition
2003-02-15

Space data and information transfer
systems — Telemetry channel coding
Systèmes de transfert des informations et données spatiales —
Codage de canal pour télémesure




Reference number
ISO 11754:2003(E)
©
ISO 2003

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ISO 11754:2003(E)
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ISO 11754:2003(E)
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.
International Standard ISO 11754 was prepared by the Consultative Committee for Space Data Systems
(CCSDS) (as CCSDS 101.0-B-5, June 2001) 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.
This second edition cancels and replaces the first edition (ISO 11754:1994), which has been technically
revised.



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INTERNATIONAL STANDARD ISO 11754:2003(E)

Space data and information transfer systems — Telemetry
channel coding
1 Scope
This International Standard specifies the requirements for telemetry channel coding of space data and
information transfer systems used in civil space applications.
The scope and field of application are furthermore detailed in subclauses 1.2 and 1.3 of the enclosed CCSDS
publication.
2 Requirements
Requirements are the technical recommendations made in the following publication (reproduced on the
following pages), which is adopted as an International Standard:
CCSDS 101.0-B-5, June 2001, Recommendation for space data system standards — Telemetry channel
coding.
For the purposes of international standardization, the modifications outlined below shall apply to the specific
clauses and paragraphs of publication CCSDS 101.0-B-5.
Pages i to v
This part is information which is relevant to the CCSDS publication only.
Page 1-3
Add the following information to the references indicated:
[1] Document CCSDS 102.0-B-5, November 2000, is equivalent to ISO 13419:2003.
1)
[2] Document CCSDS 701.0-B-3, June 2001, is equivalent to ISO 13420:— .
3 Revision of publication CCSDS 101.0-B-5
It has been agreed with the Consultative Committee for Space Data Systems that Subcommittee
ISO/TC 20/SC 13 will be consulted in the event of any revision or amendment of publication
CCSDS 101.0-B-5. To this end, NASA will act as a liaison body between CCSDS and ISO.

1) To be published. (Revision of ISO 13420:1997)
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ISO 11754:2003(E)

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ISO 11754:2003(E)

Consultative
Committeefor
SpaceDataSystems





RECOMMENDATION FOR SPACE
DATA SYSTEM STANDARDS



TELEMETRY
CHANNEL CODING



CCSDS 101.0-B-5

BLUE BOOK


June 2001


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ISO 11754:2003(E)
DEDICATION

This document is dedicated to the memory of Mr. Warner H. Miller of NASA.
Warner had been with the CCSDS since its beginning and throughout the years
he was a major contributor to numerous standards for error control coding, radio
frequency modulation, data architecture, and data compression. Warner was a
superb technologist, a gentleman, and a friend always ready to help, especially
young colleagues. Warner and his approach to work and life in general will be
deeply missed by his many friends and colleagues in the CCSDS.


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ISO 11754:2003(E)
CCSDS RECOMMENDATION FOR TELEMETRY CHANNEL CODING
AUTHORITY



Issue: Blue Book, Issue 5
Date: June 2001
Location: Oxfordshire, UK




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 Recommendations is detailed in reference [D1], and the
record of Agency participation in the authorization of this document can be obtained from the
CCSDS Secretariat at the address below.




This Recommendation is published and maintained by:

CCSDS Secretariat
Program Integration Division (Code MT)
National Aeronautics and Space Administration
Washington, DC 20546, USA
CCSDS 101.0-B-5 i June 2001
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ISO 11754:2003(E)
CCSDS RECOMMENDATION FOR TELEMETRY CHANNEL CODING
STATEMENT OF INTENT

The Consultative Committee for Space Data Systems (CCSDS) is an organization officially
established by the management of member space Agencies. 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
Recommendations and are not considered binding on any Agency.

This Recommendation is issued by, and represents the consensus of, the CCSDS Plenary
body. Agency endorsement of this Recommendation is entirely voluntary. Endorsement,
however, indicates the following understandings:

o Whenever an Agency establishes a CCSDS-related standard, this standard will be in
accord with the relevant Recommendation. Establishing such a standard does not

preclude other provisions which an Agency may develop.

o Whenever an Agency establishes a CCSDS-related standard, the Agency will provide
other CCSDS member Agencies 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
Recommendation nor any ensuing standard is a substitute for a memorandum of
agreement.

No later than five years from its date of issuance, this Recommendation 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 Recommendation is issued, existing CCSDS-
related Agency standards and implementations are not negated or deemed to be non-CCSDS
compatible. It is the responsibility of each Agency to determine when such standards or
implementations are to be modified. Each Agency is, however, strongly encouraged to direct
planning for its new standards and implementations towards the later version of the
Recommendation.
CCSDS 101.0-B-5 ii June 2001
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ISO 11754:2003(E)
CCSDS RECOMMENDATION FOR TELEMETRY CHANNEL CODING
FOREWORD

This document is a technical Recommendation for use in developing channel coding systems
and has been prepared by the Consultative Committee for Space Data Systems (CCSDS).
The telemetry channel coding concept described herein is the baseline concept for spacecraft-
to-ground data communication within missions that are cross-supported between Agencies of
the CCSDS.

This Recommendation establishes a common framework and provides a common basis for
the coding schemes used on spacecraft telemetry streams. It allows implementing
organizations within each Agency to proceed coherently with the development of compatible
derived Standards for the flight and ground systems that are within their cognizance. Derived
Agency Standards may implement only a subset of the optional features allowed by the
Recommendation and may incorporate features not addressed by the Recommendation.


Through the process of normal evolution, it is expected that expansion, deletion, or
modification of this document may occur. This Recommendation is therefore subject to
CCSDS document management and change control procedures as defined in reference [D1].
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.

CCSDS 101.0-B-5 iii June 2001
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ISO 11754:2003(E)
CCSDS RECOMMENDATION FOR TELEMETRY CHANNEL CODING

At time of publication, the active Member and Observer Agencies of the CCSDS were:

Member Agencies

– Agenzia Spaziale Italiana (ASI)/Italy.
– British National Space Centre (BNSC)/United Kingdom.
– Canadian Space Agency (CSA)/Canada.
– Centre National d’Etudes Spatiales (CNES)/France.
– Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR)/Germany.
– European Space Agency (ESA)/Europe.
– Instituto Nacional de Pesquisas Espaciais (INPE)/Brazil.
– National Aeronautics and Space Administration (NASA)/USA.
– National Space Development Agency of Japan (NASDA)/Japan.
– Russian Space Agency (RSA)/Russian Federation.

Observer Agencies

– Austrian Space Agency (ASA)/Austria.
– Central Research Institute of Machine Building (TsNIIMash)/Russian Federation.
– Centro Tecnico Aeroespacial (CTA)/Brazil.
– Chinese Academy of Space Technology (CAST)/China.
– Commonwealth Scientific and Industrial Research Organization (CSIRO)/Australia.
– Communications Research Centre (CRC)/Canada.
– Communications Research Laboratory (CRL)/Japan.
– Danish Space Research Institute (DSRI)/Denmark.
– European Organization for the Exploitation of Meteorological Satellites
(EUMETSAT)/Europe.
– European Telecommunications Satellite Organization (EUTELSAT)/Europe.
– Federal Service of Scientific, Technical & Cultural Affairs (FSST&CA)/Belgium.
– Hellenic National Space Committee (HNSC)/Greece.
– Indian Space Research Organization (ISRO)/India.
– Institute of Space and Astronautical Science (ISAS)/Japan.
– Institute of Space Research (IKI)/Russian Federation.
– KFKI Research Institute for Particle & Nuclear Physics (KFKI)/Hungary.
– MIKOMTEK: CSIR (CSIR)/Republic of South Africa.
– Korea Aerospace Research Institute (KARI)/Korea.
– Ministry of Communications (MOC)/Israel.
– National Oceanic & Atmospheric Administration (NOAA)/USA.
– National Space Program Office (NSPO)/Taipei.
– Swedish Space Corporation (SSC)/Sweden.
– United States Geological Survey (USGS)/USA.

CCSDS 101.0-B-5 iv June 2001
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ISO 11754:2003(E)
CCSDS RECOMMENDATION FOR TELEMETRY CHANNEL CODING

DOCUMENT CONTROL

Document Date Status and Substantive Changes

CCSDS Telemetry Channel May Original Issue
101.0-B-1 Coding, Issue 1 1984

CCSDS Telemetry Channel January 1. Supersedes Issue 1.
101.0-B-2 Coding, Issue 2 1987 2. Removes ASM from R-S encoded data space.
3. Specifies marker pattern for ASM.
4. Transfers Annex A (“Rationale”) to Green
Book.

CCSDS Telemetry Channel May 1. Supersedes Issue 2.
101.0-B-3 Coding, Issue 3 1992 2. Deletes Section 3 (“Convolutional Coding
with Interleaving for Tracking and Data
Relay Satellite Operations”).
3. Adds R-S interleave depths of I=2,3,4 to
existing I=1 and 5.
4. Allows R-S code to be operated in
“Standalone Mode” (i.e., not concatenated
with the convolutional code).
5. Consolidates codeblock and transfer frame
sync specifications (new Section 5).
6. Specifies a standard Pseudo-Randomizer to
improve bit synchronization (new Section 6).
7. Corrects several editorial errors.

CCSDS Telemetry Channel May 1. Supersedes Issue 3.
101.0-B-4 Coding, Issue 4 1999 2. Adds turbo code specification (new Section
4).
3. Moves normative references from front
matter to Section 1.
4. Moves informative references to Annex D.

CCSDS Telemetry Channel June 1. Supersedes Issue 4.
101.0-B-5 Coding, Issue 5 2001 2. Corrects misleading encoder diagrams.
3. Adds the following options to help near-earth
users:
– Reed-Solomon 8-error correcting code;
– a set of punctured convolutional codes
comparable to the DVB-S standard.
4. Specifies maximum frame lengths.


NOTE – Substantive technical changes from the previous issue are flagged with change
bars in the right margin.
CCSDS 101.0-B-5 v June 2001
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ISO 11754:2003(E)
CCSDS RECOMMENDATION FOR TELEMETRY CHANNEL CODING

CONTENTS

Section Page

1 INTRODUCTION.1-1

1.1 PURPOSE.1-1
1.2 SCOPE.1-1
1.3 APPLICABILITY.1-2
1.4 BIT NUMBERING CONVENTION AND NOMENCLATURE.1-2
1.5 RATIONALE.1-3
1.6 REFERENCES.1-3

2 CONVOLUTIONAL CODING .2-1

2.1 BASIC CONVOLUTIONAL CODE .2-1
2.2 PUNCTURED CONVOLUTIONAL CODES .2-4

3 REED-SOLOMON CODING .3-1

3.1 INTRODUCTION.3-1
3.2 SPECIFICATION.3-1

4 TURBO CODING .4-1

4.1 INTRODUCTION.4-1
4.2 SPECIFICATION.4-2

5 FRAME SYNCHRONIZATION .5-1

5.1 INTRODUCTION.5-1
5.2 THE ATTACHED SYNC MARKER (ASM) .5-1
5.3 ASM BIT PATTERNS .5-1
5.4 LOCATION OF ASM.5-3
5.5 RELATIONSHIP OF ASM TO REED-SOLOMON AND TURBO
CODEBLOCKS .5-3
5.6 ASM FOR EMBEDDED DATA STREAM.5-3

6 PSEUDO-RANDOMIZER .6-1

6.1 INTRODUCTION.6-1
6.2 PSEUDO-RANDOMIZER DESCRIPTION.6-1
6.3 SYNCHRONIZATION AND APPLICATION OF PSEUDO-RANDOMIZER.6-2
6.4 SEQUENCE SPECIFICATION.6-2
6.5 LOGIC DIAGRAM.6-2
CCSDS 101.0-B-5 vi June 2001
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ISO 11754:2003(E)
CCSDS RECOMMENDATION FOR TELEMETRY CHANNEL CODING

CONTENTS (continued)

Section Page

ANNEX A TRANSFORMATION BETWEEN BERLEKAMP AND
CONVENTIONAL REPRESENTATIONS .A-1
ANNEX B EXPANSION OF REED-SOLOMON COEFFICIENTS . B-1
ANNEX C GLOSSARY OF ACRONYMS AND TERMS.C-1
ANNEX D INFORMATIVE REFERENCES.D-1
ANNEX E COMPATIBLE FRAME LENGTHS FOR CCSDS CODEBLOCKS. E-1

Figure

1-1 Bit Numbering.1-2
2-1 Convolutional Encoder Block Diagram .2-3
2-2 Punctured Encoder Block Diagram.2-4
3-1 Functional Representation of R-S Interleaving .3-3
3-2 Reed-Solomon Codeblock Partitioning.3-5
4-1 Interpretation of Permutation .4-4
4-2 Turbo Encoder Block Diagram .4-5
4-3 Turbo Codeblocks for Different Code Rates.4-7
4-4 Turbo Codeblock with Attached Sync Marker.4-8
5-1 ASM Bit Pattern for Non-Turbo-Coded Data .5-2
5-2 ASM Bit Pattern for Turbo-Coded Data .5-2
5-3 Embedded ASM Bit Pattern.5-3
6-1 Pseudo-Randomizer Configuration.6-1
6-2 Pseudo-Randomizer Logic Diagram .6-3
A-1 Transformational Equivalence.A-2

Table

2-1 Puncture Code Patterns for Convolutional Code Rates .2-5
4-1 Specified Information Block Lengths .4-2
4-2 Codeblock Lengths for Supported Code Rates (Measured in Bits) .4-3
4-3 Parameters k and k for Specified Information Block Lengths.4-4
1 2
A-1 Equivalence of Representations .A-5




CCSDS 101.0-B-5 vii June 2001
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ISO 11754:2003(E)
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ISO 11754:2003(E)
CCSDS RECOMMENDATION FOR TELEMETRY CHANNEL CODING

1 INTRODUCTION

1.1 PURPOSE

The purpose of this document is to establish a common Recommendation for space telemetry
channel coding systems to provide cross-support among missions and facilities of member
Agencies of the Consultative Committee for Space Data Systems (CCSDS). In addition, it
provides focusing for the development of multi-mission support capabilities within the
respective Agencies to eliminate the need for arbitrary, unique capabilities for each mission.

Telemetry channel coding is a method of processing data being sent from a source to a
destination so that distinct messages are created which are easily distinguishable from one
another. This allows reconstruction of the data with low error probability, thus improving the
performance of the channel.

1.2 SCOPE

Several space telemetry channel coding schemes are described in this document. The
characteristics of the codes are specified only to the extent necessary to ensure
interoperability and cross-support. The specification does not attempt to quantify the relative
coding gain or the merits of each approach discussed, nor the design requirements for
encoders or decoders. Some performance information is included in Reference [D2].

This Recommendation does not require that coding be used on all cross-supported missions.
However, for those planning to use coding, the recommended codes to be used are those
described in this document.

The rate 1/2 convolutional code recommended for cross-support is described in Section 2,
“Convolutional Coding”. Depending on performance requirements, this code alone may be
satisfactory.

For telecommunication channels which are bandwidth-constrained and cannot tolerate the
increase in bandwidth required by the basic convolutional code specified in 2.1, the
punctured convolutional code specified in 2.2 has the advantage of smaller bandwidth
expansion. The Reed-Solomon code specified in Section 3 also has the advantage of smaller
bandwidth expansion and has the capability to indicate the presence of uncorrectable errors.

Where a greater coding gain is needed than can be provided by the convolutional code or
Reed-Solomon code alone, a concatenation of the convolutional code as the inner code with
the Reed-Solomon code as the outer code may be used for improved performance. The turbo
codes recommended in Section 4 may be used to obtain even greater coding gain where the
environment permits.

The recommended methods for frame (or codeblock) synchronization are described in
Section 5.
CCSDS 101.0-B-5 1-1 June 2001
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ISO 11754:2003(E)
CCSDS RECOMMENDATION FOR TELEMETRY CHANNEL CODING

To improve bit transition density as an aid to bit synchronization, a recommended method of
pseudo-randomizing data to be sent over the telemetry channel is described in Section 6.

Annex A provides a discussion of the transformation between the Berlekamp and
conventional Reed-Solomon symbol representations; Annex B provides a table showing the
expansion of Reed-Solomon coefficients; and Annex C is a glossary of coding terminology
used in this document.


1.3 APPLICABILITY

This Recommendation applies to telemetry channel coding applications of space missions
anticipating cross-support among CCSDS member Agencies at the coding layer. In addition,
it serves as a guideline for the development of compatible internal Agency Standards in this
field, based on good engineering practice.

In addition to being applicable to conventional Packet Telemetry systems [1], the codes in
this recommendation are applicable to the forward and return links of Advanced Orbiting
Systems (AOS) [2]. For coding purposes, the terms “Transfer Frame” and “Reed-Solomon
Codeblock” as used in this recommendation are understood to be equivalent to the AOS
terms “Virtual Channel Data Unit” (VCDU), and “Coded Virtual Channel Data Unit”
(CVCDU), respectively.


1.4 BIT NUMBERING CONVENTION AND NOMENCLATURE

In this document, the following convention is used to identify each bit in a forward-justified
N-bit field. The first bit in the field to be transmitted (i.e., the most left justified when
drawing a figure) is defined to be “Bit 0”; the following bit is defined to be “Bit 1” and so on
up to “Bit N-1”, as shown in Figure 1-1. When the field is used to express a binary value
(such as a counter), the Most Significant Bit (MSB) shall be the first transmitted bit of the
field, i.e., “Bit 0”.

BIT 0 BIT N-1
N-BIT DATA FIELD
FIRST BIT TRANSMITTED = MSB


Figure 1-1: Bit Numbering
CCSDS 101.0-B-5 1-2 June 2001
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ISO 11754:2003(E)
CCSDS RECOMMENDATION FOR TELEMETRY CHANNEL CODING
In accordance with modern data communications practice, spacecraft data fields are often
grouped into 8-bit “words” which conform to the above convention. Throughout this
Recommendation, the following nomenclature is used to describe this grouping:

8-BIT WORD = “OCTET”



1.5 RATIONALE

The CCSDS believes it is important to document the rationale underlying the standards
chosen, so that future evaluations of proposed changes or improvements will not lose sight of
previous decisions. The concept and rationale for Telemetry Channel Coding may be found
in Reference [D2].



1.6 REFERENCES

The following documents are referenced in this Recommendation. At the time of
publication, the editions indicated were valid. All documents are subject to revision, and
users of this Recommendation are encouraged to investigate the possibility of applying the
most recent editions of the documents indicated below. The CCSDS Secretariat maintains a
register of currently valid CCSDS Recommendations.


[1] Packet Telemetry. Recommendation for Space Data System Standards, CCSDS 102.0-
B-5. Blue Book. Issue 5. Washington, D.C.: CCSDS, November 2000.

[2] Advanced Orbiting Systems, Networks and Data Links: Architectural Specification.
Recommendation for Space Data System Standards, CCSDS 701.0-B-3. Blue Book.
Issue 3. Washington, D.C.: CCSDS, June 2001.

[3] Recommendation 2.4.9, “Minimum Modulated Symbol Transition Density on the
Space-to-Earth Link” in Radio Frequency and Modulation Systems—Part 1: Earth
Stations and Spacecraft. Recommendations for Space Data System Standards, CCSDS
401.0-B. Blue Book. Washington, D.C.: CCSDS, June 2001.

CCSDS 101.0-B-5 1-3 June 2001
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ISO 11754:2003(E)
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ISO 11754:2003(E)
CCSDS RECOMMENDATION FOR TELEMETRY CHANNEL CODING

2 CONVOLUTIONAL CODING

2.1 BASIC CONVOLUTIONAL CODE

2.1.1 BASIC CONVOLUTIONAL CODE DESCRIPTION

The basic convolutional code is a rate 1/2, constraint-length 7 transparent code which is well
suited for channels with predominantly Gaussian noise. This code is defined in 2.1.2. When
this code is punctured according to 2.2, higher code rates (lower overhead) may be achieved,
although with somewhat lower error correcting performance.

The convolutional decoder is a maximum-likelihood (Viterbi) decoder.

NOTES

1 Basic convolutional code, by itself, cannot guarantee sufficient symbol transitions
when multiplexi
...