EPISODE

2.4 RDS-TMC Standards

This section is intended to keep the reader as up to date as possible with the whole gamut of standards that need consideration in respect of RDS-TMC. This matter has been very fluid over the last 18 months, but some stability is now apparent, which will help initial implementation projects.

Note: Some of the standards listed have changed considerably since the last issue of this section.

2.4.1 RDS Standards - available from CENELEC, National Standards bodies or the EBU

EN 50067: 1992	Specification of the radio data system (RDS), April 1992

prEN 50067: 1997	Specification of the radio data system (RDS), July 1997 - this standard is an update of the 1992 edition and has undergone initial CENELEC voting. It has been elaborated by the RDS Forum and fully includes the ODA feature, originally suggested for RDS-TMC purposes and it includes specific references and "hooks" to EN 12313-1, where necessary. The former RDS-TMC references have not been removed, so the "door is left open" for non ODA implementations of RDS-TMC, in the short term. Currently Version 2.5 has been developed, with RDS Forum approval, to include all known editorial improvements and is submitted to CENELEC for final voting.

To obtain copies: go to the RDS Forum site, select item and place an electronic order.

2.4.2 RDS-TMC Standards - available from CEN only, at present

ENV 12313-1	Traffic and Traveller Information (TTI), TTI Messages via Traffic Message, part 1: Coding Protocol for RDS-TMC, (RDS-TMC using ALERT C) Version 3.0, June 1997 - this standard has recently been upgraded with changes (Note: a working version dated May 1997 is superseded) connected with the use of the RDS ODA feature to permit the Service and Network Layers to be included and to allow inter-working with the associated ALERT Plus protocol (ie incorporation of the so called Comparisons and Additions ). The Sub Working Group, CEN TC 278 SWG 4.1, has met and editorial work is being completed and then this *new* version will be submitted to CEN for voting..

prENV 12313-2	Traffic and Traveller Information (TTI), TTI Messages via Traffic Message Coding, Part 2: Event and Information codes for TMC Version 1.0, June 1996 DRAFT - this is not thought to require any further work, at present; it has been submitted to the WG4 Convenor for CEN TC 278 (Working document circulated to the CEN Technical Body). *Precise title wording changes have been proposed and may be seen on later issues.*

prENV278/7/3/0005	Geographic Road Database, Location Referencing, part 1: Location Referencing Rules for RDS-TMC, Version 1.1, March 1997 DRAFT - this work is progressing and FORCE has identified that there is considerable variation of interpretation of this standard, so that a subgroup on the Interpretation of Location Referencing Rules has been established. *Precise title wording changes have been proposed and may be seen on later issues.*

To obtain copies, apply to: CEN Central Secretariat, rue de Stassart 36, B-1050 Brussels, Belgium.

2.4.2.1 Event and Information codes

A number of projects are now working on the translation of the CEN-English Event List (to be found in prENV 12313-2) into nationally agreeable Lists. Details should be obtained from the FORCE/ECORTIS Projects Country Coordinators. The EPISODE Project may be contacted for assistance.

2.4.3 RDS Universal Encoder Communications Protocol - available from EBU only

EBU SPB 490

Universal Encoder Communications Protocol (5^th Revision) July 1997 - this de facto standard is now available in Version 5.1, dated 22 August 1997. It is operated by many major Broadcasters and Transmission Operators in Europe and defines the data stream used between broadcast centres and transmitters where the RDS Encoders are situated. It has been upgraded to include the full ODA set of commands and the special RDS-TMC commands. This has been undertaken by WG 5 of the RDS Forum and is now issued. It not only includes the commands, because the UECP also effectively provides the full "encoder model", to allow developers to satisfy the dynamic multiplex requirements of the RDS data stream to convey all RDS features, including the special timing requirements of RDS-TMC.

To obtain a copy: go to the RDS Forum site, select item (may still be referenced as Version 4.0 for a while, but you know what you want, now!) and place an electronic order.

2.4.4 Open Data Applications - Application Identification

The RDS Registrations Office has issued an Application ID (4.4.97) for use within ODA transmissions of RDS carrying TMC according to the so called "ALERT C" protocol, as described in the standards described above.

Application Name:	RDS-TMC: ALERT C
Application Description:	This Application is intended to provide an RDS-TMC service, using the ALERT C protocol in an ODA. It is fully described in the three specification references cited below.
Open Data mode:	1.1
Capacity requirements:	Maximum of 2 groups per second (including type 1A, 3A, and 8A groups). Subject to review in early 1999, after field implementation experiences.

Application ID:

decimal 52550
hex CD46
bin 1100 1101 0100 0110

Notes:

Transmissions carrying this AID must adhere fully to the specifications/provisions of the above references. (Any subsequent updates, that do not change the fundamental requirements for the transmission of RDS-TMC using ALERT C as an ODA, may allow continued use of the same AID, but advice should be sought from the RDS Registrations Office at the EBU.)
All transmissions must conform to CENELEC prEN 50067:1997, dated July 1997, Specification of the radio data system (RDS), Version 2.5 or later.
Users of this AID must satisfy themselves as to the validity of using it and the accuracy of all related information and must accept all due consequence. The RDS Registrations Office is not liable for any incidental, special or consequential damages arising out of the use or inability to use this AID, whether in transmission or reception equipment.

PREVIOUS PAGE			NEXT PAGE
HOME	CONTENTS	SPLIT SCREEN	FULL SCREEN