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194

ETSI ES 201 980 V4.1.2 (2017-04)

Annex T (informative):

Assignment of Service identifiers

T.0 Introduction

The Service identifier is defined to be a 24-bit number (see clause 6.3.4). To achieve reliable receiver behaviour, care need to be taken to ensure that Service identifiers are unique worldwide. This annex describes how to manage the assignment of Service identifiers.

T.1 Domestic services

These services, primarily designed to be consumed in the country of transmission, are generally regulated by national authorities. Therefore, it makes sense for national bodies to allocate Service identifiers to ensure uniqueness. Conflict between Service identifiers would only come from the reception of transmissions from neighbouring countries, or from international services. The former can be dealt with by coordination between countries and the latter can be achieved by ensuring that international services and domestic services are restricted to using particular ranges of the 24-bit coding space.

The RDS system (see IEC 62106 [13]) has allocated Country Codes (CC) and Extended Country Codes (ECC) for most countries. It is recommended that domestic services construct the 24-bit Service identifier by allocating the 8-most significant bits to the ECC, the next 4-bits to the CC(s), and the remaining 12-bits for individual services. In general, this provides a maximum of 4 096 services per country, although some countries have more than one country code (e.g. the USA has 14 providing 57 344 service codes).

To allow for future provision, all codes from 0xA00000 to 0xFFFFFF are designated for allocation using this method (total of 6 291 456 services).

T.2 International services

The High Frequency Coordination Committee (HFCC) and some other bodies coordinate frequencies used in the HF bands for international services. The HFCC has indicated that it will allocate and coordinate DRM Service identifiers for the services for which it provides frequency coordination. The 24-bit code, in the range 0x000000 to 0x9FFFFF (total of 9 437 184 services), should be allocated by a random mechanism. This is because DRM provides service information via the FAC and SDC describing each broadcast in terms of language, label, etc., and it is therefore not necessary to include this information in the Service identifier in any form; indeed doing so causes limitations to the total number of codes that can be allocated because certain combinations will never be used. It is further recommended that no system is applied to the allocation relating the code to any physical characteristics of the broadcast (e.g. DRM mode, frequency, etc.) for the same reasons.

It is recommended that the HFCC (or other issuing body) should generate Service identifier codes randomly from the available stock and allocate them to services. When a service ceases to be transmitted, the code is released back to the issuing body for re-use after a suitable period. The issuing body maintains a central database of codes that have been allocated, but it is not necessary to publish that information.

Broadcaster's have the responsibility to check to the best of their ability that no other current broadcast is using the same Service identifier value. In case a clash of identifiers is detected, the involved broadcasters should resolve the situation as quickly as possible to avoid unexpected receiver behaviour.

ETSI

195

ETSI ES 201 980 V4.1.2 (2017-04)

Annex U (informative):

Bibliography

DRM Output Requirements, November 1999.

ITU-R Circular letter LCCE/39: "Submission of candidate systems for digital sound broadcasting at frequencies below 30 MHz", September 1999.

Recommendation ITU-R BS.1348: "Service requirements for digital sound broadcasting at frequencies below 30 MHz".

Recommendation ITU-R BS.1349: "Implementation of digital sound broadcasting to vehicular, portable and fixed receivers using terrestrial transmitters in the LF, MF and HF bands".

Recommendation ITU-R BS.559-2: "Objective measurement of radio-frequency protection ratios in LF, MF and HF broadcasting".

Recommendation ITU-R SM.328-10: "Spectra and bandwidth of emissions".

ETSI

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