Grundig Digital Radio - Manual (Page 107)

DIGITAL RADIO GUIDE APPENDIX A: EUREKA 147
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TPEG can be transported within the DAB system in the Transparent Data Channel (TDC) in a
stream-like format; bytes come out in the same order they go in.
29 The TDC Specification allows
TPEG data to be carried in three modes: packet mode, stream mode and X-PAD. Nevertheless,
this approach which is specified in the present version of the DAB standard, involves several
problems in terms of reception reliability and interpretation. It has therefore been proposed to
transport TPEG as one of the multimedia applications in the MOT data channel. This would imply
the following main advantages: MOT is already implemented in most receivers and enables
efficient object compression, power saving and delta updates and has much lower overhead than
TDC.
Advanced demodulation technique for COFDM
The Communications Research Centre Canada (CRC) developed an advanced COFDM
demodulation technique
30
which reduces the effect of the Doppler effect and therefore increases
the maximum speed, allowing vehicle speeds up to 140 km/s while achieving a target bit error
rate (BER) of 10-4 . Canadian DAB broadcasters use L-Band (1452 to 1492 MHz) and would like
to use Transmission Mode IV instead of Mode II, because the former allows for a larger
separation distance between on-channel re-transmitters than in the case of Mode II. However,
Mode IV in L-Band limits the speed to less than 100 km/h, so this new technique could help.
Further studies are required to investigate whether this technique could be useful for VHF bands
and whether the chip manufacturers could accommodate it readily into their chip design.
Technical Standards
International Standards
ETSI Standards
31
Eureka 147 standards are formalised by ETSI and are available for download. The current list of
ETSI standards relating to Eureka 147 are in Table A.3. The main ETSI standard for Eureka 147
is EN 300 401.
Table A.3: ETSI Standards relating to Eureka 147
Number Title
EN 300 401 V1.3.3
(May 2001) Digital Audio Broadcasting (DAB); DAB to mobile, portable and fixed
receivers
(THIRD EDITION)
EN 300 797 V1.1.1 Digital Audio Broadcasting (DAB); Distribution interfaces; Service
Transport Interface (STI)
EN 300 798 V1.1.1 Digital Audio Broadcasting (DAB); Distribution interfaces; Digital
baseband In-phase and Quadrature (DIQ) Interface
EN 301 234 V1.2.1 Digital Audio Broadcasting (DAB); Multimedia Object Transfer (MOT)
protocol
EN 301 700 V1.1.1 Digital Audio Broadcasting (DAB); Service Referencing from FM-RDS;
29 Guidelines for TPEG in DAB, B/TPEG Plenary Group 00/113 available from www.ebu.ch/bmc_btpeg.htm
30 Thibault, Zhang, Boudreau, Taylor, Chouinard: Advanced Demodulation Technique for COFDM in Fast Fading
Channels, IBC 2003 Proceedings, p. 416 to 422
31 EBU BPN 062