IEC PAS 62272-1:2002

IEC/PAS 62272-1
Edition 1.0
2002-05
Digital Radio Mondiale (DRM) –
System specification
for digital transmissions
in the broadcasting bands
below 30 MHz
PUBLI C LY AVAI LABLE SPECI F I CATI O N
IN TER N A TION AL
E L E C T R OT E CHNI CA L
Reference number
C O MMI S S I O N
IEC/PAS 62272-1
ETSI TS 101 980 V1.1.1 (2001-09)

Technical Specification
Digital Radio Mondiale (DRM);
System Specification
INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
DIGITAL RADIO MONDIALE (DRM) –

System specification for digital transmissions

in the broadcasting bands below 30 MHz

FOREWORD
A PAS is a technical specification not fulfilling the requirements for a standard, but made available to the
public and established in an organization operating under given procedures.
IEC-PAS 62272-1 is identical to ETSI specification TS 101980. The ETSI document is the result of a co-operation
between Digital Radio Mondiale Consortium (DRM) and the European Telecommunications Standards Institute
(ETSI)
Both ETSI and DRM expressed their willingness to have this ETSI document published as an IEC PAS.
IEC-PAS 62272-1 has been processed by IEC technical committee 103: Transmitting equipment for radio-
communication.
The text of this PAS is based on the This PAS was approved for
following document: publication by the P-members of the
committee concerned as indicated in
the following document:
Draft PAS Report on voting
103/24/PAS 103/25/RVD
Following publication of this PAS, the technical committee or subcommittee concerned will investigate the
possibility of transforming the PAS into an International Standard.
1) The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprising all
national 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
addition to 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 IEC collaborates closely with the International Organization for Standardization (ISO) in accordance

with conditions determined by agreement between the two organizations.
2) The formal decisions or agreements of the IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all interested
National Committees.
3) The documents produced have the form of recommendations for international use and are published in the form of
standards, technical specifications, technical reports or guides and they are accepted by the National Committees in
that sense.
4) In order to promote international unification, IEC National Committees undertake to apply IEC International Standards
transparently to the maximum extent possible in their national and regional standards. Any divergence between the
IEC 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
equipment declared to be in conformity with one of its standards.
6) Attention is drawn to the possibility that some of the elements of this PAS may be the subject of patent rights. The
IEC shall not be held responsible for identifying any or all such patent rights.
Page i
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Contents
Intellectual Property Rights.6

Foreword .6

Introduction .6

1 Scope.8

2 References.8

3 Definitions, symbols and abbreviations .9
3.1 Definitions . 9
3.2 Symbols . 9
3.3 Abbreviations. 10
4 General characteristics .11
4.1 System overview. 11
4.2 System architecture. 11
4.3 Source coding . 13
4.4 Transmission modes . 14
4.4.1 Signal bandwidth related parameters. 14
4.4.2 Transmission efficiency related parameters . 14
4.4.2.1 Coding rates and constellations . 14
4.4.2.2 OFDM parameter set . 14
5 Source coding modes .16
5.1 Overview. 16
5.1.1 AAC Audio Coding. 17
5.1.2 MPEG CELP coding . 17
5.1.3 MPEG HVXC coding. 18
5.1.4 SBR coding . 18
5.2 UEP and audio super framing. 18
5.3 AAC coding. 19
5.3.1 AAC . 19
5.3.1.1 AAC audio super frame. 20
5.3.2 AAC + SBR. 22
5.4 MPEG CELP coding. 23
5.4.1 MPEG CELP. 23
5.4.1.1 CELP audio super frame. 25
5.5 HVXC. 27
5.5.1 Definitions. 28
5.5.1.1 HVXC source coder parameters . 28
5.5.1.2 CRC bits for fixed bit rate modes . 28

5.5.2 HVXC decoder. 28
5.5.3 HVXC encoder. 29
5.5.3.1 LPC analysis and LSP quantization. 30
5.5.3.2 Open loop pitch search . 30
5.5.3.3 Harmonic magnitude and fine pitch estimation. 30
5.5.3.4 Vector quantization of harmonic magnitudes. 30
5.5.3.5 Voiced/Unvoiced decision. 30
5.5.3.6 VXC coding of unvoiced signals. 30
5.5.4 HVXC channel coding . 31
5.5.4.1 Protected Bit Selection . 31
5.5.4.2 Syntax of DRM HVXC error resilience (ErHVXCfixframe_CRC) . 33
5.5.5 Category Interleaving. 37
5.5.6 HVXC error detection and concealment . 38
5.5.6.1 Cyclic Redundancy Code (CRC). 38
5.5.6.2 Error concealment. 38
5.5.6.2.1 Parameter replacement. 39
5.6 SBR. 41

– 3–
5.6.1 Conceptual overview. 41

5.6.2 AAC + SBR Decoding Process. 42

5.6.2.1 Analysis Filterbank. 42

5.6.2.2 Synthesis Filterbank . 42

5.6.2.3 Gain Control . 43
5.6.2. 4 T/F Grid Control. 43
5.6.2.5 Huffman Decoder . 43

5.6.3 AAC + SBR Protocol. 46

5.6.3.1 AAC + SBR syntax . 46

5.6.3.2 SBR bit stream element definitions . 52

6 Multiplex definition .56
6.1 Introduction. 56
6.2 Main Service Channel. 56

6.2.1 Introduction. 56
6.2.2 Structure . 56
6.2.3 Building the MSC. 57
6.2.3.1 Multiplex frames. 57
6.2.3.2 Hierarchical frames. 57
6.2.4 Reconfiguration. 57
6.3 Fast Access Channel . 57
6.3.1 Introduction. 57
6.3.2 Structure . 57
6.3.3 Channel parameters. 58
6.3.4 Service parameters . 59
6.3.5 CRC. 61
6.3.6 FAC repetition. 61
6.4 Service Description Channel. 61
6.4.1 Introduction. 61
6.4.2 Structure . 61
6.4.3 Data Entities. 62
6.4.3.1 Multiplex description data entity - type 0. 63
6.4.3.2 Label data entity - type 1 . 64
6.4.3.3 Conditional access parameters data entity - type 2. 64
6.4.3.4 Frequency information data entity - type 3. 64
6.4.3.5 Frequency schedule data entity - type 4. 67
6.4.3.6 Application information data entity - type 5. 68
6.4.3.7 Announcement support and switching entity - type 6 . 69
6.4.3.8 Region definition data entity - type 7 . 70
6.4.3.9 Time and date information data entity - type 8. 71
6.4.3.10 Audio information data entity - type 9. 71
6.4.3.11 FAC channel parameters data entity - type 10. 73
6.4.3.12 Linkage data entity - type 11 . 75
6.4.3.13 Language and country data entity - type 12. 75
6.4.3.14 Other data entities. 76
6.4.4 Summary of data entity characteristics. 76

6.4.5 Changing the content of the SDC. 76
6.4.6 Signalling of reconfigurations. 77
6.4.6.1 Service reconfigurations . 77
6.4.6.2 Channel reconfigurations. 77
6.5 Text message application. 78
6.5.1 Structure . 78
6.6 Packet mode. 79
6.6.1 Packet structure . 80
6.6.1.1 Header . 80
6.6.1.2 Data field . 81
6.6.2 Asynchronous streams. 81
6.6.3 Files. 81
6.6.4 Choosing the packet length . 81
7 Channel coding and modulation.82
7.1 Introduction. 82

– 4–
7.2 Transport multiplex adaptation and Energy dispersal. 82

7.2.1 Transport multiplex adaptation . 82

7.2.1.1 MSC. 82

7.2.1.2 FAC . 85

7.2.1.3 SDC . 85
7.2.2 Energy dispersal . 86
7.3 Coding. 87

7.3.1 Multilevel coding . 87

7.3.1.1 Partitioning of bitstream in SM and HMsym. 89

7.3.1.2 Partitioning of bitstream in HMmix. 90

7.3.2 Component Code. 91

7.3.3 Bit Interleaving. 97

7.3.3.1 FAC . 97

7.3.3.2 SDC . 98
7.3.3.3 MSC. 98
7.4 Signal constellations and mapping. 100
7.5 Application of coding to the channels. 104
7.5.1 Coding the MSC. 104
7.5.1.1 SM . 104
7.5.1.2 HMsym. 105
7.5.1.3 HMmix . 105
7.5.2 Coding the SDC . 106
7.5.3 Coding the FAC . 106
7.6 MSC Cell Interleaving . 106
7.7 Mapping of MSC cells on the transmission super frame structure . 108
8 Transmission structure .109
8.1 Transmission frame structure and modes. 109
8.2 Propagation-related OFDM parameters . 111
8.3 Signal bandwidth related parameters . 111
8.3.1 Parameter definition . 111
8.3.2 Simulcast transmission. 113
8.4 Pilot cells . 113
8.4.1 Functions and derivation . 113
8.4.2 Frequency references. 113
8.4.2.1 Cell positions. 113
8.4.2.2 Cell gains and phases. 114
8.4.3 Time references. 114
8.4.3.1 Cell positions and phases. 115
8.4.3.2 Cell gains. 116
8.4.4 Gain references. 117
8.4.4.1 Cell positions. 117
8.4.4.2 Cell gains. 117
8.4.4.3 Cell phases. 118
8.4.4.3.1 Procedure for calculation of cell phases. 118
8.4.4.3.2 Robustness mode A. 118

8.4.4.3.3 Robustness mode B. 119
8.4.4.3.4 Robustness mode C. 119
8.4.4.3.5 Robustness mode D. 119
8.5 Control cells. 120
8.5.1 General . 120
8.5.2 FAC cells. 121
8.5.2.1 Cell positions. 121
8.5.2.2 Cell gains and phases. 122
8.5.3 SDC cells. 123
8.5.3.1 Cell positions. 123
8.5.3.2 Cell gains and phases. 123
8.6 Data cells . 123
8.6.1 Cell positions. 123
8.6.2 Cell gains and phases . 123

– 5–
Annex A (informative): Simulated system performance .124

Annex B (informative): Definition of channel profiles.125

Annex C (informative): Example of mapping of logical frames to multiplex frames .128

Annex D (normative): Calculation of the CRC word .129

Annex E (informative): Indicative RF Protection ratios .131

Annex F (informative): Guidelines for emitter implementation.133

Annex G (informative): Guidelines for receiver implementation .134

G.1 Alternative frequency checking and switching (AFS) .134
G.2 Character sets .136
Annex H (informative): Service capacity and bit rates .137
Annex I (normative): Audio tables.138
Annex J (informative): Numbers of input bits.141
Annex K (informative): Simulcast transmission.146
Annex L (informative): Pilot reference illustrations.148
Annex M (informative): MSC configuration examples.152
Annex N (informative): HVXC parameters.155
Annex O (informative): Bibliography.157
History.158

– 6–
Intellectual Property Rights
IPRs essential or potentially essential to the present document may have been declared to ETSI. The information
p ertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found
i n ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in
respect of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web

server (http://www.etsi.org/legal/home.htm).

Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee

can be given as to the existence of other IPRs not referenced in ETSI SR 000 314 (or the updates on the ETSI Web

server) which are, or may be, or may become, essential to the present document.

Foreword
This Technical Specification (TS) has been produced by Joint Technical Committee (JTC) of the European
Broadcasting Union (EBU), Comité Européen de Normalization Electrotechnique (CENELEC) and the European
Telecommunications Standards Institute (ETSI).
NOTE: The EBU/ETSI JTC Broadcast was established in 1990 to co-ordinate the drafting of standards in the
specific field of broadcasting and related fields. Since 1995 the JTC Broadcast became a tripartite body
by including in the Memorandum of Understanding also CENELEC, which is responsible for the
standardization of radio and television receivers. The EBU is a professional association of broadcasting
organizations whose work includes the co-ordination of its members' activities in the technical, legal,
programme-making and programme-exchange domains. The EBU has active members in about
60 countries in the European broadcasting area; its headquarters is in Geneva.
European Broadcasting Union
CH-1218 GRAND SACONNEX (Geneva)
Switzerland
Tel: +41 22 717 21 11
Fax: +41 22 717 24 81
Introduction
The frequency bands used for broadcasting below 30 MHz are:
• 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 from
525 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 or
period in the (approximately) 11 year sunspot cycle;
• Portable and mobile reception with relatively little impairment caused by the environment surrounding the
receiver.
– 7–
There is thus a desire to continue broadcasting in these bands, perhaps especially in the case of international

broadcasting where the HF bands offer the only reception possibilities which do not also involve the use of local

repeater 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 in

this 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 reception

techniques in order to provide the increase in quality which is needed to retain listeners who, increasingly, have a wide
variety 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 Digital
Radio Mondiale (DRM) consortium was formed in early 1998. The DRM consortium is a non-profit making body
which seeks to develop and promote the use of the DRM system worldwide. Its members include broadcasters, network
providers, receiver and transmitter manufacturers and research institutes. More information is available from their
website (http://www.drm.org/).

– 8–
DIGITAL RADIO MONDIALE (DRM) –

System specification for digital transmissions

in the broadcasting bands below 30 MHz

1 Scope
T he present document gives the specification for the Digital Radio Mondiale (DRM) system for digital transmissions in
the broadcasting bands below 30 MHz.

2 References
The following documents contain provisions which, through reference in this text, constitute provisions of the present
document.
• References are either specific (identified by date of publication and/or edition number or version number) or
non-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: "Information technology - Coding of audio-visual objects - Part 3: Audio".
[3] ISO/IEC 14496-3/Amd 1: "Audio extensions".
[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 the
frequency 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: Latin alphabet No. 1".
[10] ETSI TS 101 756: "Digital Audio Broadcasting (DAB); Registered Tables".
[11] ITU-R Recommendation BS.559-2: "Objective measurement of radio-frequency protection ratios
in LF, MF and HF broadcasting".
[12] ITU-R Recommendation SM.328-10: "Spectra and bandwidth of emissions".

– 9–
3 Definitions, symbols and abbreviations

3.1 Definitions
F or the purposes of the present document, the following terms and definitions apply:

cell: sine wave portion of duration T , transmitted with a given amplitude and phase and corresponding to a carrier
s
position
NOTE 1: Each OFDM symbol is the sum of K such sine wave portions equally spaced in frequency.

energy dispersal: operation involving deterministic selective complementing of bits in the logical frame, intended to
reduce the possibility that systematic patterns result in unwanted regularity in the transmitted signal
Fast Access Channel (FAC): channel of the multiplex data stream which contains the information that is necessary to
find services and begin to decode the multiplex
Main Service Channel (MSC): channel of the multiplex data stream which occupies the major part of the transmission
frame and which carries all the digital audio services, together with possible supporting and additional data services
mod: the modulo operator
NOTE 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 held
constant on each of the equally-spaced carriers in the signal
reserved for future addition (rfa): bits with this designation shall be set to zero
NOTE 3: Receivers shall ignore these bits.
reserved for future use (rfu): bits with this designation shall be set to zero
NOTE 4: Receivers shall check that these bits are zero in order to determine the valid status of the other fields in
the same scope.
Service Description Channel (SDC): channel of the multiplex data stream which gives information to decode the
services included in the multiplex
NOTE 5: The SDC also provides additional information to enable a receiver to find alternative sources of the same
data.
Single Frequency Network (SFN): network of transmitters sharing the same radio frequency to achieve a large area
coverage
transmission frame: a number of consecutive OFDM symbols (duration of 400 ms), whereby the first OFDM symbol
contains the time reference cells
transmission super frame: three consecutive transmission frames (duration of 1 200 ms), whereby the first OFDM
symbols contain the SDC block
logical frame: contains data of one stream during 400 ms
multiplex 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 Symbols
For the purposes of the present document, the following symbols apply:
E[ ] expectation value of the expression in brackets

– 10 –
f reference frequency of the emitted signal
c
K number of active carriers in the OFDM symbol

K carrier index of the upper active carrier in the OFDM signal
max
K carrier index of the lower active carrier in the OFDM signal
min
L number of input bits per multiplex frame for the multilevel encoding
MUX
N number of MSC cells (QAM symbols) per multiplex frame
MUX
1/3
T elementary time period, equal to 83 μs (1/12 kHz)

T duration of the transmission frame, equal to 400 ms
f
T duration of the guard interval
g
T duration of an OFDM symbol
s
T duration of the transmission super-frame built from three transmission frames
sf
T duration of the useful (orthogonal) part of an OFDM symbol, excluding the guard interval
u
X* complex conjugate of value X
round towards plus infinity

round towards minus infinity

3.3 Abbreviations
For the purposes of the present document, the following abbreviations apply:
AAC Advanced Audio Coding
AFS Alternative Frequency Switching
BER Bit Error Ratio
CELP Code Excited Linear Prediction
CRC Cyclic Redundancy Check
DFT Discrete Fourier Transform
EEP Equal Error Protection
FAC Fast Access Channel
HF High Frequency
HVXC Harmonic Vector eXcitation Coding
IFFT Inverse Fast Fourier Transform
ISO International Organization for Standardization
LF Low Frequency
LPC Linear Predictive Coding
LSb Least Significant bit
LSP Line Spectral Pairs
MF Medium Frequency
MPEG Moving Picture Experts Group
MSb Most Significant bit
MSC Main Service Channel
OFDM Orthogonal Frequency Division Multiplexing

PRBS Pseudo-Random Binary Sequence
QAM Quadrature Amplitude Modulation
RF Radio Frequency
rfa reserved for future addition
rfu reserved for future use
SBR Spectral Band Replication
SDC Service Description Channel
SFN Single Frequency Network
SM Simple Modulation
SPP Standard Protecte
...