Tiêu chuẩn iso 11754 2003 scan

INTERNATIONAL STANDARD IS0 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 IS0 11754:2003(E) Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS @ Not for Resale IS0 2003 IS0 11754:2003(E) PDF disclaimer This PDF file may contain embedded typefaces In accordance with Adobe's licensing policy, this file may be printed or viewed but shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing In downloading this file, parties accept therein the responsibility of not infringing Adobe's licensing policy The IS0 Central Secretariat accepts no liability in this area Adobe is a trademark of Adobe Systems Incorporated Details of the sofiware products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation parameters were optimized for printing Every care has been taken to ensure that the file is suitable for use by IS0 member bodies In the unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below `,,,`-`-`,,`,,`,`,,` - O IS02003 All rights reserved Unless othetwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either IS0 at the address below or ISOs member body in the country of the requester IS0 copyright office Case postale 56 CH-I211 Geneva 20 Tel + 41 22 749 O1 11 Fax + 41 22 749 O9 47 E-mail copyright@iso.org Web www.iso.org Published in Switzerland ii Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS O IS0 2003 -All rights reserved Not for Resale IS0 11754:2003(E) Foreword IS0 (the International Organization for Standardization) is a worldwide federation of national standards bodies (IS0 member bodies) The work of preparing International Standards is normally carried out through IS0 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 SO, also take part in the work IS0 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 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 IS0 shall not be held responsible for identifying any or all such patent rights International Standard IS0 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 of this International Standard) by Technical Committee ISOíTC 20, Aircraft and space vehicles, Subcommittee SC 13, Space data and information transfer systems This second edition cancels and replaces the first edition (IS0 11754:1994), which has been technically revised `,,,`-`-`,,`,,`,`,,` - iii O IS0 2003 -All rights reserved Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS Not for Resale `,,,`-`-`,,`,,`,`,,` - Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS Not for Resale INTERNATIONAL STANDARD IS0 11754:2003(E) Space data and information transfer systems - Telemetry channel coding 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 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: [I] Document CCSDS 102.0-B-5, November 2000, is equivalent to IS0 13419:2003 [2] Document CCSDS 701.0-B-3, June 2001, is equivalent to IS0 13420:-1) Revision of publication CCSDS 101.0-B-5 It has been agreed with the Consultative Committee for Space Data Systems that Subcommittee ISOíTC 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 SO 1) To be published (Revision of I S 13420:1997) `,,,`-`-`,,`,,`,`,,` - O IS0 2003 -All rights reserved Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS Not for Resale IS0 11754:2003(E) (Blank page) `,,,`-`-`,,`,,`,`,,` - O IS0 2003 -All rights reserved Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS Not for Resale IS0 11754:2003(E) Consultative Committee for Space Data Systems RECOMMENDATION FOR SPACE DATA SYSTEM STANDARDS `,,,`-`-`,,`,,`,`,,` - TELEMETRY CHANNEL CODING CCSDS 101.0-B-5 BLUE BOOK June 2001 O IS0 2003 -All rights reserved Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS Not for Resale IS0 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 Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS O IS0 2003 -All rights reserved Not for Resale IS0 11754:2003(E) CCSDS RECOMMENDATION FOR TELEMETRY CHANNEL CODING AUTHORITY Issue: Blue Book, Issue Date: June 2001 Location: Oxfordshire, UJS 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 [Dl], and the record of Agency participation in the authorization of this document can be obtained fi-om 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 `,,,`-`-`,,`,,`,`,,` - June 2001 CCSDS 101.0-B-5 O IS0 2003 -All rights reserved Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS Not for Resale IS0 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: o The standard itself The anticipated date of initial operational capability The anticipated duration of operational service 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 fi-om 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 CCSDSrelated 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 June 200 11 `,,,`-`-`,,`,,`,`,,` - Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS O IS0 2003 -All rights reserved Not for Resale IS0 11754:2003(E) CCSDS RECOMMENDATIONFOR TELEMETRY CHANNEL CODING POLY IN ALPHA 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 01101011 11010110 00101011 01010110 10101100 11011111 00111001 01110010 11100100 01001111 10011110 10111011 11110001 01100101 11001010 00010011 00100110 01001100 10011000 10110111 11101001 o 1o 1o 1o 1o 1o 1o 1o 11010011 00100001 01000010 10000100 10001111 10011001 10110101 11101101 01011101 CCSDS 101.0-B-5 POLY IN ALPHA e0 1234567 00101101 11010010 11000010 01011111 00000010 01010011 11101011 00101010 00010111 01011000 11000111 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 11001001 01110011 11100001 00110111 01010010 11011010 10001100 11110001 1o 1o 1o 1o 00001111 10001011 00110100 00110000 10010111 118 119 12o 121 122 123 124 01000000 00010100 00111010 10001010 00000101 10010110 01110001 125 126 A-6 52 Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS 10111010 11110011 01100001 11000010 00000011 00000110 00001100 00011000 00110000 01100000 11000000 00000111 00001110 00011100 00111000 01110000 11100000 01000111 10001110 10011011 10110001 11100101 01001101 10011010 10110011 11100001 01000101 10001010 10010011 10100001 11000101 00001101 e0 1234567 10110010 11011100 01111000 11001101 11010100 00110110 01100011 01111100 01101010 00000011 01100010 01001101 11001100 11100101 10010000 10000101 10001110 10100010 01000001 00100101 10011100 01101100 11110111 01011110 00110011 11110101 00001101 11011000 11011111 00011010 10000000 00011000 June 2001 O IS0 2003 -All rights reserved Not for Resale `,,,`-`-`,,`,,`,`,,` - Table A-1: Cont’d IS0 11754:2003(E) CCSDS RECOMMENDATIONFOR TELEMETRY CHANNEL CODING Table A-1: Cont’d POLY IN ALPHA 127 `,,,`-`-`,,`,,`,`,,` - 128 129 13O 131 132 133 134 135 136 137 138 139 14O 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 00011010 00110100 01101000 11010000 00100111 01001110 10011100 10111111 11111001 01110101 11101010 01010011 10100110 11001011 00010001 00100010 01000100 10001000 10010111 10101001 11010101 00101101 01011010 10110100 11101111 01011001 10110010 11100011 01000001 10000010 10000011 10000001 CCSDS 1O 1.0-B-5 POLY IN ALPHA e01234567 11010011 11110011 11111001 11100100 10100001 00100011 01101000 01010000 10001001 01100111 11011011 10111101 01010111 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 01001100 11111101 01000011 01110110 01110111 01000110 11100000 00000110 11110100 00111100 01111110 00111001 11101000 01001000 01011010 10010100 00100010 01011001 11110110 178 179 180 181 182 183 184 185 186 187 188 189 190 A-7 01101111 10010101 00010011 11111111 00010000 10011101 01011101 01010001 10111000 11000001 00111101 01001111 10011111 00001110 10111010 10010010 11010110 01100101 10001000 01010110 01111101 01011011 10100101 10000100 10111111 00000100 10100111 11010111 01010100 00101110 10110000 10001111 June 2001 53 O IS0 2003 -All rights reserved Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS 10000101 10001101 10011101 10111101 11111101 01111101 11111010 01110011 11100110 01001011 10010110 10101011 11010001 00100101 01001010 10010100 10101111 11011001 00110101 01101010 11010100 00101111 01011110 10111100 11111111 01111001 11110010 01100011 11000110 00001011 00010110 00101100 e01234567 Not for Resale IS0 11754:2003(E) CCSDS RECOMMENDATION FOR TELEMETRY CHANNEL CODING Table A-1: Concluded P O W E R 191 192 193 194 195 196 197 198 199 200 201 202 203 04 205 206 207 208 209 210 211 212 213 14 215 216 217 218 219 220 221 222 POLY IN ALPHA 01011000 10110000 11100111 01001001 10010010 10100011 11000001 00000101 00001010 00010100 00101000 01010000 10100000 11000111 00001001 00010010 00100100 01001000 10010000 10100111 11001001 00010101 00101010 01010100 10101000 11010111 00101001 01010010 10100100 11001111 00011001 00110010 CCSDS 101.0-B-5 P O e0 1234567 W E R 10010011 11100111 11000011 01101110 10100100 10110101 00011001 11100010 o 1o 1o 1o 00011111 00010110 01101001 01100001 00101111 10000001 00101001 01110101 00010101 00001011 00101100 11100011 01100100 10111001 11110000 10011011 223 224 225 226 227 228 229 23 O 231 232 233 234 235 236 237 238 239 24 O 241 242 243 244 245 246 247 10101001 01101101 248 249 250 251 252 253 54 11000110 11111000 11010101 00000111 11000101 POLY IN ALPHA e01234567 01100100 11001000 00010111 00101110 01011100 10111000 11110111 01101001 11010010 00100011 01000110 10001100 10011111 10111001 11110101 01101101 11011010 00110011 01100110 11001100 00011111 00111110 01111100 11111000 01110111 11101110 01011011 10110110 11101011 01010001 10100010 11000011 10011010 10011000 11001011 00100000 00001010 00011101 01000101 10000010 01001011 00111000 11011001 11101110 10111100 01100110 11101010 00011011 10110001 10111110 00110101 00000001 00110001 10100110 11100110 11110010 11001000 01000010 01000111 11010001 10100000 00010010 11001110 10110110 June 2001 A-8 `,,,`-`-`,,`,,`,`,,` - 54 Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS O IS0 2003 -All rights reserved Not for Resale `,,,`-`-`,,`,,`,`,,` - IS0 11754:2003(E) CCSDS RECOMMENDATION FOR TELEMETRY CHANNEL CODING ANNEX B EXPANSION OF REED-SOLOMON COEFFICIENTS (This annex is not part of the Recommendation.) Purpose: While the equations given in the Reed-Solomon Coding Section of this recommendation are fully specifjmg, this Annex provides additional assistance for those implementing either the B = 16 or the B = code ForB= 16: COEFFICIENTS OF g(x) POLYNOMIAL IN a a7 a6 a5 a4 a3 a2 al 0 0 0 0 1 1 ao 0 0 1 0 0 0 0 1 1 0 0 1 1 0 1 0 0 0 1 0 0 1 1 1 1 1 1 0 0 0 1 0 1 0 1 0 1 0 0 1 1 0 0 1 0 1 1 0 1 1 0 1 Note that G3 = G29 = G13 = G19 Further information, including encoder block diagrams, is provided by Perlman and Lee in Reference [D3] CCSDS 101.0-B-5 B- 55 O IS0 2003 -All rights reserved Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS June 2001 Not for Resale IS0 11754:2003(E) `,,,`-`-`,,`,,`,`,,` - CCSDS RECOMMENDATION FOR TELEMETRY CHANNEL CODING For B = 8: COEFFICIENTS OF g(x) CCSDS 101.0-B-5 POLYNOMIAL IN a a7 a6 a5 a4 a3 a2 al ao O o O o o o 0 0 1 1 o 0 1 0 1 1 0 0 1 1 1 1 0 0 1 0 0 0 0 B-2 June 2001 56 Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS O IS0 2003 -All rights reserved Not for Resale IS0 11754:2003(E) CCSDS RECOMMENDATION FOR TELEMETRY CHANNEL CODING `,,,`-`-`,,`,,`,`,,` - ANNEX C GLOSSARY OF ACRONYMS AND TERMS (This annex is not part of the Recommendation.) C PURPOSE This annex defines key acronyms and terms that are used throughout this Recommendation to describe telemetry channel coding C TERMS BLOCK ENCODING: A one-to-one transformation of sequences of length k of elements of a source alphabet to sequences of length n of elements of a code alphabet, n>k CHANNEL SYMBOL: The unit of output of the innermost encoder CODEBLOCK A codeblock of an (n,k) block code is a sequence of n channel symbols which were produced as a unit by encoding a sequence of k information symbols, and will be decoded as a unit CODE RATE: The average ratio of the number of binary digits at the input of an encoder to the number of binary digits at its output CODEWORD: In a block code, one of the sequences in the range of the one-to-one transformation (see BLOCK ENCODING) CONCATENATION: The use of two or more codes to process data sequentially with the output of one encoder used as the input of the next CONNECTION VECTOR (FORWARD): In convolutional and turbo coding, a vector used to specify one of the parity checks to be computed by the shift register(s) in the encoder For a shift register with s stages, a connection vector is an s-bit binary number A bit equal to “one” in position i (counted fi-om the left) indicates that the output of the ith stage of the shift register is to be used in computing that parity check CONNECTION VECTOR (BACKWARD): In turbo coding, a vector used to specify the feedback to the shift registers in the encoder For a shift register with s stages, a backward connection vector is an s-bit binary number A bit equal to “one” in position i (counted fi-om the left) indicates that the output of the ith stage of the shift register is to be used in computing the feedback value, except for the leftmost bit which is ignored CCSDS 1O 1.0-B-5 c-1 57 O IS0 2003 -All rights reserved Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS June 2001 Not for Resale IS0 11754:2003(E) CCSDS RECOMMENDATION FOR TELEMETRY CHANNEL CODING CONSTRAINT LENGTH: In convolutional coding, the number of consecutive input bits that are needed to determine the value of the output symbols at any time CONVOLUTIONAL CODE: As used in this document, a code in which a number of output symbols are produced for each I input information bit Each output symbol is a linear combination of the current input bit as well as some or all of the previous k-1 bits where k is the constraint length of the code GF(n): The Galois Field consisting of exactly “n” elements `,,,`-`-`,,`,,`,`,,` - INNER CODE: In a concatenated coding system, the last encoding algorithm that is applied to the data stream The data stream here consists of the codewords generated by the outer decoder MODULATING WAVEFORM: A way of representing data bits (“1” and “û”) by a particular waveform NRZ-L: A modulating waveform in which a data “one” is represented by one of two levels, and a data “zero” is represented by the other level NRZ-M: A modulating waveform in which a data “one” is represented by a change in level and a data “zero” is represented by no change in level OUTER CODE: In a concatenated coding system, the first encoding algorithm that is applied to the data stream PUNCTURED CODE: As used in this document, a code obtained by deleting some of the parity symbols generated by the convolutional encoder before transmission The bandwidth efficiency obtained by puncturing is increased compared to the original code, although the minimum weight (and therefore its error-correcting performance) will be less than that of the original code REED-SOLOMON (R-S) SYMBOL: A set of J bits that represents an element in GF(2J), the code alphabet of a J-bit Reed-Solomon code SYSTEMATIC CODE: A code in which the input information sequence appears in unaltered form as part of the output codeword TRANSPARENT CODE: A code that has the property that complementing the input of the encoder or decoder results in complementing the output TRELLIS TERMINATION: The operation of filling with zeros the s stages of each shift register used in the turbo encoder, after the end of the information block During trellis termination the encoders continue to output encoded symbols for s-1 additional clock cycles TURBO CODE: As used in this document, a block code formed by combining two component recursive convolutional codes A turbo code takes as input a block of k information bits The input block is sent unchanged to the first component code and bit-wise interleaved (see CCSDS 101.0-B-5 c-2 June 2001 50 Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS O IS0 2003 -All rights reserved Not for Resale IS0 11754:2003(E) CCSDS RECOMMENDATION FOR TELEMETRY CHANNEL CODING TURBO CODE PERMUTATION) to the second component code The output is formed by the parity symbols contributed by each component code plus a replica of the information bits TURBO CODE PERMUTATION: A fixed bit-by-bit permutation of the entire input block of information bits performed by an interleaver, used in turbo codes VIRTUAL FILL: In a systematic block code, a codeword can be divided into an information part and a parity (check) part Suppose that the information part is N symbols long (a symbol is defined here to be an element of the code?s alphabet) and that the parity part is A4 symbols long A ?shortened? code is created by taking only S (S < N ) information symbols as input, appending a fixed string of length N-S and then encoding in the normal way This fixed string is called ?fill? Since the fill is a predetermined sequence of symbols, it need not be transmitted over the channel Instead, the decoder appends the same fill sequence before decoding In this case, the fill is called ?Virtual Fill? CCSDS 1O 1.0-B-5 c-3 June 2001 `,,,`-`-`,,`,,`,`,,` - 59 O IS0 2003 -All rights reserved Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS Not for Resale IS0 11754:2003(E) `,,,`-`-`,,`,,`,`,,` - (Blank page) O IS0 2003 -All rights reserved 60 Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS Not for Resale IS0 11754:2003(E) CCSDS RECOMMENDATION FOR TELEMETRY CHANNEL CODING ANNEX D INFORMATIVE REFERENCES (This annex is not part of the Recommendation.) [Dl] Procedures Manual for the Consultative Committeefor Space Data Systems CCSDS AOO.O-Y-7 Yellow Book Issue Washington, D.C.: CCSDS, November 1996 [D2] Channel Coding-Summary of Concept and Rationale Report Concerning Space Data System Standards, CCSDS 100.0-G-2 Green Book Issue Washington, D.C.: CCSDS, [under development] [D3] M Perlman and J Lee Reed-Solomon Encoders-Conventional vs Berlekamp 's Architecture JPL Publication 82-71 Pasadena, California: NASA-Jet Propulsion Laboratory, December 1982 CCSDS 1O 1.0-B-5 D- June 2001 `,,,`-`-`,,`,,`,`,,` - 61 O IS0 2003 -All rights reserved Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS Not for Resale IS0 11754:2003(E) (Blank page) `,,,`-`-`,,`,,`,`,,` - O IS0 2003 -All rights reserved 62 Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS Not for Resale IS0 11754:2003(E) CCSDS RECOMMENDATION FOR TELEMETRY CHANNEL CODING ANNEX E COMPATIBLE FRAME^ LENGTHS FOR CCSDS CODEBLOCKS (This annex is not part of the Recommendation.) El PURPOSE The purpose of this annex is to summarize the length constraints on fi-ames imposed by the use of the Channel Codes specified in this Recommendation NOTES Recommendations [i] and [2] require that any Transfer Frame or VCDU not operating on a channel using the Reed-Solomon Code of Section must include a Cyclic Redundancy Check (CRC) to be included to provide validation It follows that a fi-ame on an uncoded channel must also carry the CRC None of the coding techniques recommended (except for the rate=1/2 convolutional code with the inverter) can by itself guarantee sufficient transitions to keep receiver symbol synchronizers in lock Unless the data, coding, or modulation technique chosen can guarantee sufficient transitions, the pseudo-randomizer is required by Section of this recommendation E2 FRAME LENGTHS WITH CONVOLUTIONAL CODING The Convolutional Codes of Section are not block-oriented codes, so they impose no constraint on the length of the transfer fi-ame or VCDU However, other length constraints specified in [ 11 and [2] must still be observed Frame, as used in this annex, includes the Telemetry “Transfer Frame” as defined in [i] and the AOS “Virtual Channel Data Unit” (VCDU) as defined in [2] CCSDS 101.0-B-5 E- June 200 `,,,`-`-`,,`,,`,`,,` - 63 O IS0 2003 -All rights reserved Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS Not for Resale IS0 11754:2003(E) CCSDS RECOMMENDATION FOR TELEMETRY CHANNEL CODING E3 E3.1 FRAME LENGTHS WITH REED-SOLOMON CODING GENERAL With the Reed-Solomon Codes specified in Section 3, only certain specific lengths of transfer fi-ames may be contained within the codeblock’s data space In some cases these lengths may be shortened in discrete steps by using virtual fill at a small sacrifice in coding gain Since these R-S codes have a symbol length of bits, the length of the codeblock must be a combined multiple of bits and the interleaving depth This will give “octet compatibility” If high-speed efficiency is needed for “32-bit compatibility” (with 32-bit processors, for example) then the length of the codeblock must be a combined multiple of bits, the interleaving depth, and 32 bits NOTES The Advanced Orbiting Systems Recommendation [2] specifies a limited set of codeblock lengths, and only the E=16 case for the channel code It is undergoing revision by the CCSDS to include the E=8 option In each table below, lengths are given in bits with equivalent octets in (parentheses) `,,,`-`-`,,`,,`,`,,` - E3.2 TRANSFER FRAMES FOR OCTET COMPATIBILITY, E=16 The following are allowed lengths for Transfer Frames when octet compatibility is sufficient and the Reed-Solomon E=16 code is selected Maximum lengths are shown; shorter lengths are permitted in discrete steps using the concept of “Virtual Fill” and shortening the transmitted codeblock length by the steps shown in the last column Reed-Solomon Interleave Depth (I) CCSDS 1O 1.0-B-5 Maximum Transfer Frame Length Maximum Transmitted Codeblock Length, E=16 Transfer Frame (and transmitted codeblock) may be shortened in multiples of 1784 (223) 3568 (446) 5352 (669) 7136 (892) 8920 (1 115) 2040 (255) 4080 (510) 6120 (765) 8160 (1020 10200 (1275) (1) 16 (2) 24 (3) 32 (4) 40 ( ) E-2 June 2001 64 Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS O IS0 2003 -All rights reserved Not for Resale IS0 11754:2003(E) CCSDS RECOMMENDATION FOR TELEMETRY CHANNEL CODING E3.3 TRANSFER FRAMES FOR OCTET COMPATIBILITY, E=8 The following are allowed lengths for Transfer Frames when octet compatibility is sufficient and the Reed-Solomon E=8 code is selected Maximum lengths are shown; shorter lengths are permitted in discrete steps using the concept of “Virtual Fill” and shortening the transmitted codeblock length by the steps shown in the last column R-S Interleave Depth Maximum Transfer Frame Length Maximum Transmitted Codeblock Length, E=8 1912 (239) 3824 (478) 5736 (717) 7648 (956) 9560 (1 195) 2040 (255) 4080 (510) 6120 (765) 8160 (1020) 10200 (1275) (I) E4 Transfer Frame (and transmitted codeblock) may be further shortened in multiples of FRAME LENGTHS WITH TURBO CODING The Turbo Codes specified in Section of this Recommendation are block codes Therefore, the fi-ame length must match the information block lengths for the selected turbo code `,,,`-`-`,,`,,`,`,,` - Performance for only the following information block lengths have been validated by CCSDS and approved for use These lengths will accommodate both Version Transfer Frames [ 11 and Version VCDUs [2] Values are in bits 1784, 3568, 7136, 8920, 16384’ NOTES Frame synchronizers should be set to account for the Attached Sync Marker, whose length must be added to the turbo codeblock length as specified in Table 4-2 The ASM pattern and length depend on the turbo code rate as shown in Figure 4-4 Recommendations [ 11 and [2] require that if the Reed-Solomon Code is not used, a Cyclic Redundancy Check (CRC) is required as part of the Transfer Frame or VCDU for validation purposes Interleaver parameters for the length 16384 bits are under study by the CCSDS Until finalized, use of this option is not recommended CCSDS 101.0-B-5 E-3 65 O IS0 2003 -All rights reserved Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS June 2001 Not for Resale `,,,`-`-`,,`,,`,`,,` - IS0 11754:2003(E) ICs 49.140 Price based on 47 pages O IS0 2003 -All rights reserved Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS Not for Resale