EN 62272-1:2003

STANDARDDigitalni radio Mondiale (DRM) - 1. del: Sistemska specifikacija (IEC 62272-1:2003)Digital Radio Mondiale (DRM) - Part 1: System
specification (IEC 62272-1:2003)©
Standard je založil in izdal Slovenski inštitut za standardizacijo. Razmnoževanje ali kopiranje celote ali delov tega dokumenta ni dovoljenoReferenčna številkaSIST EN 62272-1:2004(en)ICS33.170

EUROPEAN STANDARD
EN 62272-1 NORME EUROPÉENNE EUROPÄISCHE NORM
December 2003 CENELEC European Committee for Electrotechnical Standardization Comité Européen de Normalisation Electrotechnique Europäisches Komitee für Elektrotechnische Normung
Central Secretariat: rue de Stassart 35, B - 1050 Brussels
© 2003 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 62272-1:2003 E
ICS 33.060.20
English version
Digital Radio Mondiale (DRM) Part 1: System specification (IEC 62272-1:2003)
Digital Radio Mondiale (DRM) Partie 1: Spécification du système (CEI 62272-1:2003)
Digital Radio Mondiale (DRM) Teil 1: Systemspezifikation (IEC 62272-1:2003)
This European Standard was approved by CENELEC on 2003-09-23. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CENELEC member into its own language and notified to the Central Secretariat has the same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Lithuania, Luxembourg, Malta, Netherlands, Norway, Portugal, Slovakia, Spain, Sweden, Switzerland and United Kingdom.

Foreword The text of document 103/32/FDIS, future edition 1 of IEC 62272-1, prepared by IEC TC 103, Transmitting equipment for radiocommunication, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 62272-1 on 2003-09-23. The following dates were fixed: – latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement
(dop) 2004-07-01 – latest date by which the national standards conflicting
with the EN have to be withdrawn
(dow) 2006-10-01
Annexes designated "normative" are part of the body of the standard.
Annexes designated "informative" are given for information only.
In this standard, annexes D and I are normative and annexes A to C and E to H and J to N are informative. __________ Endorsement notice The text of the International Standard IEC 62272-1:2003 was approved by CENELEC as a European Standard without any modification. __________

NORMEINTERNATIONALECEIIECINTERNATIONALSTANDARD62272-1Première éditionFirst edition2003-03Digital Radio Mondiale (DRM) –Partie 1:Spécification du systèmeDigital Radio Mondiale (DRM) –Part 1:System specificationPour prix, voir catalogue en vigueurFor price, see current catalogue© IEC 2003
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Copyright - all rights reservedAucune partie de cette publication ne peut être reproduite niutilisée sous quelque forme que ce soit et par aucun procédé,électronique ou mécanique, y compris la photocopie et lesmicrofilms, sans l'accord écrit de l'éditeur.No part of this publication may be reproduced or utilized in anyform or by any means, electronic or mechanical, includingphotocopying and microfilm, without permission in writing fromthe publisher.International Electrotechnical Commission,
3, rue de Varembé, PO Box 131, CH-1211 Geneva 20, SwitzerlandTelephone: +41 22 919 02 11
Telefax: +41 22 919 03 00
E-mail: inmail@iec.ch
Web: www.iec.chCODE PRIXPRICE CODEXJCommission Electrotechnique InternationaleInternational Electrotechnical Commission

62272-1 © IEC:2003– 3 –CONTENTSFOREWORD.11INTRODUCTION.151Scope.172References.173Definitions, symbols, abbreviations and conventions.173.1Definitions.173.2Symbols.193.3Abbreviations.213.4Convention.214General characteristics.234.1System overview.234.2System architecture.234.3Source coding.274.4Transmission modes.294.4.1Signal bandwidth related parameters.294.4.2Transmission efficiency related parameters.294.4.2.1Coding rates and constellations.294.4.2.2OFDM parameter set.295Source coding modes.335.1Overview.335.1.1AAC Audio Coding.335.1.2MPEG CELP coding.355.1.3MPEG HVXC coding.355.1.4SBR coding.375.2UEP and audio super framing.375.3AAC coding.395.3.1AAC.395.3.1.1AAC audio super frame.415.3.2AAC + SBR.455.4MPEG CELP coding.475.4.1MPEG CELP.475.4.1.1CELP audio super frame.495.5HVXC.555.5.1Definitions.575.5.1.1HVXC source coder parameters.575.5.1.2CRC bits for fixed bit rate modes.575.5.2HVXC decoder.575.5.3HVXC encoder.595.5.3.1LPC analysis and LSP quantization.615.5.3.2Open loop pitch search.615.5.3.3Harmonic magnitude and fine pitch estimation.615.5.3.4Vector quantization of harmonic magnitudes.615.5.3.5Voiced/Unvoiced decision.615.5.3.6VXC coding of unvoiced signals.615.5.4HVXC channel coding.635.5.4.1Protected Bit Selection.635.5.4.2Syntax of DRM HVXC error resilience (ErHVXCfixframe_CRC).675.5.5Category Interleaving.75

62272-1 © IEC:2003– 5 –5.5.6HVXC error detection and concealment.775.5.6.1Cyclic Redundancy Code (CRC).775.5.6.2Error concealment.775.5.6.2.1Parameter replacement.795.6SBR.835.6.1Conceptual overview.835.6.2AAC + SBR Decoding Process.855.6.2.1Analysis Filterbank.875.6.2.2Synthesis Filterbank.875.6.2.3Frequency Band Tables.915.6.2.3.1Master Frequency Band Table.915.6.2.3.2Derived Frequency Band Tables.935.6.2.4T/F Grid Control.1015.6.2.5Huffman Decoder.1055.6.2.5.1Envelope and Noise Floor Decoding.1055.6.2.5.2Dequantization and Stereo Decoding.1075.6.2.6HF Generator.1095.6.2.6.1Limiter Frequency Band Table<0}.1155.6.2.7High frequency adjustment.1195.6.2.7.1Mapping.1195.6.2.7.2Estimation of Current Envelope.1195.6.2.7.3Calculation of Noise Levels.1215.6.2.7.4Calculation of Gain.1215.6.2.7.5Assembling HF Signals.1235.6.2.8Low Complexity Stereo.1255.6.2.8.1Process.1255.6.3AAC + SBR Protocol.1295.6.3.1AAC + SBR syntax.1295.6.3.2SBR bit stream element definitions.1436Multiplex definition.1516.1Introduction.1516.2Main Service Channel.1516.2.1Introduction.1516.2.2Structure.1516.2.3Building the MSC.1536.2.3.1Multiplex frames.1536.2.3.2Hierarchical frames.1536.2.4Reconfiguration.1536.3Fast Access Channel.1536.3.1Introduction.1536.3.2Structure.1536.3.3Channel parameters.1556.3.4Service parameters.1576.3.5CRC.1616.3.6FAC repetition.1616.4Service Description Channel.1616.4.1Introduction.1616.4.2Structure.1636.4.3Data Entities.1636.4.3.1Multiplex description data entity - type 0.1656.4.3.2Label data entity - type 1.1676.4.3.3Conditional access parameters data entity - type 2.1696.4.3.4Frequency information data entity - type 3.1696.4.3.5Frequency schedule data entity - type 4.1756.4.3.6Application information data entity - type 5.1756.4.3.7Announcement support and switching entity - type 6.179

62272-1 © IEC:2003– 7 –6.4.3.8Region definition data entity - type 7.1816.4.3.9Time and date information data entity - type 8.1816.4.3.10Audio information data entity - type 9.1816.4.3.11FAC channel parameters data entity - type 10.1856.4.3.12Linkage data entity - type 11.1896.4.3.13Language and country data entity - type 12.1916.4.3.14Other data entities.1916.4.4Summary of data entity characteristics.1916.4.5Changing the content of the SDC.1936.4.6Signalling of reconfigurations.1936.4.6.1Service reconfigurations.1956.4.6.2Channel reconfigurations.1956.5Text message application.1956.5.1Structure.1956.6Packet mode.1996.6.1Packet structure.1996.6.1.1Header.2016.6.1.2Data field.2016.6.2Asynchronous streams.2016.6.3Files.2036.6.4Choosing the packet length.2037Channel coding and modulation.2037.1Introduction.2037.2Transport multiplex adaptation and Energy dispersal.2057.2.1Transport multiplex adaptation.2057.2.1.1MSC.2057.2.1.2FAC.2097.2.1.3SDC.2097.2.2Energy dispersal.2117.3Coding.2137.3.1Multilevel coding.2137.3.1.1Partitioning of bitstream in SM.2177.3.1.2Partitioning of bitstream in HMsym.2197.3.1.3Partitioning of bitstream in HMmix.2217.3.2Component Code.2217.3.3Bit Interleaving.2337.3.3.1FAC.2337.3.3.2SDC.2337.3.3.3MSC.2357.4Signal constellations and mapping.2377.5Application of coding to the channels.2457.5.1Coding the MSC.2457.5.1.1SM.2457.5.1.2HMsym.2477.5.1.3HMmix.2477.5.2Coding the SDC.2497.5.3Coding the FAC.2497.6MSC Cell Interleaving.2517.7Mapping of MSC cells on the transmission super frame structure.2538Transmission structure.2578.1Transmission frame structure and modes.2578.2Propagation-related OFDM parameters.2598.3Signal bandwidth related parameters.2598.3.1Parameter definition.2598.3.2Simulcast transmission.263

62272-1 © IEC:2003– 9 –8.4Pilot cells.2638.4.1Functions and derivation.2638.4.2Frequency references.2638.4.2.1Cell positions.2658.4.2.2Cell gains and phases.2658.4.3Time references.2658.4.3.1Cell positions and phases.2678.4.3.2Cell gains.2718.4.4Gain references.2718.4.4.1Cell positions.2718.4.4.2Cell gains.2718.4.4.3Cell phases.2738.4.4.3.1Procedure for calculation of cell phases.2738.4.4.3.2Robustness mode A.2738.4.4.3.3Robustness mode B.2758.4.4.3.4Robustness mode C.2758.4.4.3.5Robustness mode D.2758.5Control cells.2778.5.1General.2778.5.2FAC cells.2778.5.2.1Cell positions.2778.5.2.2Cell gains and phases.2818.5.3SDC cells.2818.5.3.1Cell positions.2818.5.3.2Cell gains and phases.2818.6Data cells.2818.6.1Cell positions.2818.6.2Cell gains and phases.283Annex A (informative)
Simulated system performance.285Annex B (informative)
Definition of channel profiles.287Annex C (informative)
Example of mapping of logical frames to multiplex frames.291Annex D (normative)
Calculation of the CRC word.293Annex E (informative)
Indicative RF Protection ratios.297Annex F (informative)
Guidelines for transmitter implementation.301Annex G (informative)
Guidelines for receiver implementation.303Annex H (informative)
Service capacity and bit rates.311Annex I (normative)
SBR tables.313Annex J (informative)
Numbers of input bits.353Annex K (informative)
Simulcast transmission.361Annex L (informative)
Pilot reference illustrations.365Annex M (informative)
MSC configuration examples.373Annex N (informative)
HVXC parameters.379Bibliography.383

62272-1 © IEC:2003– 11 –INTERNATIONAL ELECTROTECHNICAL COMMISSION____________Digital Radio Mondiale (DRM)Part 1: System specificationFOREWORD1)The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprising allnational electrotechnical committees (IEC National Committees). The object of the IEC is to promote international co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and in additionto other activities, the IEC publishes International Standards. Their preparation is entrusted to technical committees;any IEC National Committee interested in the subject dealt with may participate in this preparatory work. International,governmental and non-governmental organizations liaising with the IEC also participate in this preparation. The IECcollaborates closely with the International Organization for Standardization (ISO) in accordance with conditionsdetermined by agreement between the two organizations.2)The formal decisions or agreements of the IEC on technical matters express, as nearly as possible, an internationalconsensus of opinion on the relevant subjects since each technical committee has representation from all interestedNational Committees.3)The documents produced have the form of recommendations for international use and are published in the form ofstandards, technical specifications, technical reports or guides and they are accepted by the National Committees inthat sense.4)
In order to promote international unification, IEC National Committees undertake to apply IEC International Standardstransparently to the maximum extent possible in their national and regional standards. Any divergence between theIEC Standard and the corresponding national or regional standard shall be clearly indicated in the latter.5)
The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any equipmentdeclared to be in conformity with one of its standards.6)
Attention is drawn to the possibility that some of the elements of this International Standard may be the subject ofpatent rights. The IEC shall not be held responsible for identifying any or all such patent rights.International standard IEC 62272-1 has been prepared by IEC technical committee 103:Transmitting equipment for radiocommunication.This standard is based on the technical specification ETSI TS 101 980 V1.2.1 (2002) and wasprepared by Joint Rapporteur Group ITU/IEC (CA Decision 110/20) which includes TC 103,Transmitting equipment for radiocommunication, working group dealing with this matter: document103/18/NP(Digital radio in the bands below 30 MHz - Part 1: System aspects)The joint rapporteur Group has been set up to achieve a double logo standard (IEC and ITU).The double logo standard may be published after the approval of the content of this standard byITU.The text of this standard is based on the following documents:FDISReport on voting103/32/FDIS103/33/RVDFull information on the voting for the approval of this standard can be found in the report on votingindicated in the above table.This standard does not follow the rules for structuring International Standards as given in Part 2 ofthe ISO/IEC Directives.NOTE
This standard has been reproduced without significant modification to its original content or drafting.

62272-1 © IEC:2003– 13 –The committee has decided that the contents of this publication will remain unchanged until 2005.At this date, the publication will be•reconfirmed;•withdrawn;•replaced by a revised edition, or•amended.

62272-1 © IEC:2003– 15 –INTRODUCTIONThis part of IEC 62272 describes as follows the frequency bands used for broadcasting below 30 MHz:•Low frequency (LF) band - from 148,5 kHz to 283,5 kHz, in ITU Region 1 [1]* only;•Medium frequency (MF) band - from 526,5 kHz to 1 606,5 kHz, in ITU Regions 1 [1] and 3 [1] and from525 kHz to 1 705 kHz in ITU Region 2 [1];•High frequency (HF) bands - a set of individual broadcasting bands in the frequency range 2,3 MHz to 27 MHz,generally available on a Worldwide basis.These bands offer unique propagation capabilities that permit the achievement of:•Large coverage areas, whose size and location may be dependent upon the time of day, season of the year orperiod in the (approximately) 11 year sunspot cycle;•Portable and mobile reception with relatively little impairment caused by the environment surrounding thereceiver.There is thus a desire to continue broadcasting in these bands, perhaps especially in the case of internationalbroadcasting where the HF bands offer the only reception possibilities which do not also involve the use of localrepeater stations.However, broadcasting services in these bands:•use analogue techniques;•are subject to limited quality;•are subject to considerable interference as a result of the long-distance propagation mechanisms which prevail inthis part of the frequency spectrum and the large number of users.As a direct result of the above considerations, there is a desire to effect a transfer to digital transmission and receptiontechniques in order to provide the increase in quality which is needed to retain listeners who, increasingly, have a widevariety of other programme reception media possibilities, usually already offering higher quality and reliability.In order to meet the need for a digital transmission system suitable for use in all of the bands below 30 MHz, the DigitalRadio Mondiale (DRM) consortium was formed in early 1998. The DRM consortium is a non-profit making bodywhich seeks to develop and promote the use of the DRM system worldwide. Its members include broadcasters, networkproviders, receiver and transmitter manufacturers and research institutes. More information is available from theirwebsite (http://www.drm.org/).
*
The figures in square brackets refer to the references given in clause 2.

62272-1 © IEC:2003– 17 –Digital Radio Mondiale (DRM)Part 1: System specification1 ScopeThis part of IEC 62272 gives the specification for the Digital Radio Mondiale (DRM) system for digital transmissionsin the broadcasting bands below 30 MHz.2 ReferencesThe following documents contain provisions which, through reference in this text, constitute provisions of the presentdocument.•References are either specific (identified by date of publication and/or edition number or version number) ornon-specific.•For a specific reference, subsequent revisions do not apply.•For a non-specific reference, the latest version applies.[1]ITU-R Radio Regulations.[2]ISO/IEC 14496-3:2001, Information technology - Coding of audio-visual objects - Part 3: Audio[3]Not used[4]ETSI EN 300 401: Radio Broadcasting Systems; Digital Audio Broadcasting (DAB) to mobile,portable and fixed receivers[5]EN 50067: Specification of the radio data system (RDS) for VHF/FM sound broadcasting in thefrequency range from 87,5 to 108,0 MHz[6]ISO/IEC 10646-1: Information technology - Universal Multiple-Octet Coded Character Set(UCS) - Part 1: Architecture and Basic Multilingual Plane[7]ISO 639-2: Codes for the representation of names of languages - Part 2: Alpha-3 code[8]ISO 3166 (all parts): Codes for the representation of names of countries and their subdivisions[9]ISO 8859-1: Information technology - 8-bit single-byte coded graphic character sets - Part 1: Latinalphabet No. 1[10]ITU-R Recommendation BS.559-2: Objective measurement of radio-frequency protection ratios inLF, MF and HF broadcasting[11]ITU-R Recommendation SM.328-10: Spectra and bandwidth of emissions[12]ITU-R Recommendation XXX: RF protection ratios for digital sound broadcasting (DRM system)in the broadcasting bands below 30 MHz. (under consideration)3 Definitions, symbols, abbreviations and conventions3.1 DefinitionsFor the purposes of the present document, the following terms and definitions apply:cell: sine wave portion of duration sT, transmitted with a given amplitude and phase and corresponding to a carrierpositionNOTE 1:Each OFDM symbol is the sum of K such sine wave portions equally spaced in frequency.

62272-1 © IEC:2003– 19 –energy dispersal: operation involving deterministic selective complementing of bits in the logical frame, intended toreduce the possibility that systematic patterns result in unwanted regularity in the transmitted signalFast Access Channel (FAC): channel of the multiplex data stream which contains the information that is necessary tofind services and begin to decode the multiplexMain Service Channel (MSC): channel of the multiplex data stream which occupies the major part of the transmissionframe and which carries all the digital audio services, together with possible supporting and additional data servicesmod: the modulo operatorNOTE 2:(x mod y) = z, where y > 0, such that x = qy + z, q is an integer, and 0 ≤ z < y.OFDM symbol: transmitted signal for that portion of time when the modulating amplitude and phase state is heldconstant on each of the equally-spaced carriers in the signalreserved for future addition (rfa): bits with this designation shall be set to zeroNOTE 3:Receivers shall ignore these bits.reserved for future use (rfu): bits with this designation shall be set to zeroNOTE 4:Receivers shall check that these bits are zero in order to determine the valid status of the other fields inthe same scope.Service Description Channel (SDC): channel of the multiplex data stream which gives information to decode theservices included in the multiplexNOTE 5:The SDC also provides additional information to enable a receiver to find alternative sources of the samedata.Single Frequency Network (SFN): network of transmitters sharing the same radio frequency to achieve a large areacoveragetransmission frame: a number of consecutive OFDM symbols (duration of 400 ms), whereby the first OFDM symbolcontains the time reference cellstransmission super frame: three consecutive transmission frames (duration of 1 200 ms), whereby the first OFDMsymbols contain the SDC blocklogical frame: contains data of one stream during 400 msmultiplex frame: logical frames from all streams form a multiplex frame (duration of 400 ms)NOTE 6:It is the relevant basis for coding and interleaving.3.2 SymbolsFor the purposes of the present document, the following symbols apply:E[ ]expectation value of the expression in bracketscfreference frequency of the emitted signalKnumber of active carriers in the OFDM symbolmaxKcarrier index of the upper active carrier in the OFDM signalminKcarrier index of the lower active carrier in the OFDM signalLMUXnumber of input bits per multiplex frame for the multilevel encodingNMUXnumber of MSC cells (QAM symbols) per multiplex frameTelementary time period, equal to 831/3µs (1/12 kHz)fTduration of the transmission frame, equal to 400 msgTduration of the guard interval

62272-1 © IEC:2003– 21 –sTduration of an OFDM symbolTsfduration of the transmission super frame built from three transmission framesuTduration of the useful (orthogonal) part of an OFDM symbol, excluding the guard intervalX*complex conjugate of value Xªºround towards plus infinity¬¼round towards minus infinity3.3 AbbreviationsFor the purposes of the present document, the following abbreviations apply:AACAdvanced Audio CodingAFSAlternative Frequency SwitchingBERBit Error RateCELPCode Excited Linear PredictionCRCCyclic Redundancy CheckDFTDiscrete Fourier TransformEEPEqual Error ProtectionFACFast Access ChannelHFHigh FrequencyHVXCHarmonic Vector eXcitation CodingIFFTInverse Fast Fourier TransformISOInternational Organization for StandardizationLFLow FrequencyLPCLinear Predictive CodingLSbLeast Significant bitLSPLine Spectral PairsMFMedium FrequencyMPEGMoving Picture Experts GroupMSbMost Significant bitMSCMain Service ChannelOFDMOrthogonal Frequency Division MultiplexingPRBSPseudo-Random Binary SequenceQAMQuadrature Amplitude ModulationRFRadio Frequencyrfareserved for future additionrfureserved for future useSBRSpectral Band ReplicationSDCService Description ChannelSFNSingle Frequency NetworkSMStandard MappingSPPStandard Protected PartUEPUnequal Error Protectionuimsbfunsigned integer most significant bit firstVSPPVery Strongly Protected Part3.4 ConventionUnless otherwise stated, the following convention, regarding the order of bits within each step of processing is used:-in figures, the bit shown in the left hand position is considered to be first-in tables, the bit shown in the left hand position is considered to be first-in numerical fields, the Most Significant Bit (MSb) is considered to be first and denoted by the higher number.For example, the MSb of a single byte is denoted "b7" and the Least Significant Bit (LSb) is denoted "b0"-in vectors (mathematical expressions), the bit with the lowest index is considered to be first

62272-1 © IEC:2003– 23 –4 General characteristics4.1 System overviewThe DRM system is designed to be used at any frequency below 30 MHz, i.e. within the long wave, medium wave andshort wave broadcasting bands, with variable channelization constraints and propagation conditions throughout thesebands. In order to satisfy these operating constraints, different transmission modes are available. A transmission mode isdefined by transmission parameters classified in two types:-signal bandwidth related parameters;-transmission efficiency related parameters.The first type of parameters defines the total amount of frequency bandwidth for one transmission. Efficiency relatedparameters allow a trade-off between capacity (useful bit rate) and ruggedness to noise, multipath and Doppler.4.2 System architectureThis subclause gives a general presentation of the system architecture, based on the synoptic diagram of figure 1, whichgives reference to the subclauses defining the individual parts of the system.Figure 1 describes the general flow of different classes of information (audio, data, …) and does not differentiatebetween different services that may be conveyed within one or more classes of information. A detailed description onthe distribution of services onto those classes can be found in clause 6.

62272-1 © IEC:2003
– 25 –sourceencoder(s)pre-coderpre-coderpre-codermultiplexerenergydispersalenergydispersalenergydispersalchannelencoderchannelencoderchannelencoderOFDM signalgeneratormodulatoraudio datastreamSDCinformationFACinformationdatastreamFACSDCMSCnormal prot.[high prot.]DRM transmission signalflow of informationnormal prot.[high prot.]cellinterleavernormal/[high]protectionOFDM cell mapperpilot generatorFigure 1 – Conceptual DRM transmission block diagramIEC
479/03
62272-1 © IEC:2003– 27 –The source encoder and pre-coders ensure the adaptation of the input streams onto an appropriate digital transmissionformat. For the case of audio source encoding, this functionality includes audio compression techniques as described in4.3 and in clause 5. The output of the source encoder(s) and the data stream pre-coder may comprise two parts requiringdifferent levels of protection within the subsequent channel encoder. All services have to use the same two levels ofprotection.The multiplexer combines the protection levels of all data and audio services as described in clause 6.The energy dispersal provides a deterministic selective complementing of bits in order to
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