Grundig Digital Radio User Manual
DIGITAL RADIO GUIDE
TERRESTRIAL TRANSMISSION SYSTEMS - DRM
18
Extensive field tests have verified these performance statements.
(2)
Selecting, demodulating and decoding of a DRM system signal at a receiver
A receiver must be able to detect which particular DRM system mode is being
transmitted to handle it properly. This is done by way of the use of many of the
field entries within the FAC and SDC.
transmitted to handle it properly. This is done by way of the use of many of the
field entries within the FAC and SDC.
Once the appropriate mode is identified (and is repeatedly verified), the
demodulation process is the inverse of that shown in Figure 4.1. Similarly, the
receiver is also informed which services are present, and, for example, how source
decoding of an audio service should be performed.
demodulation process is the inverse of that shown in Figure 4.1. Similarly, the
receiver is also informed which services are present, and, for example, how source
decoding of an audio service should be performed.
For much more detail on DRM system, refer to the following references
•
ETSI ES 201 980 v 2.1.1 (2004-06): the “signal in the air” specification
•
ETSI TS 101 968 v0.0.2 (2002-08): the data applications specification
•
ETSI TS 102 820 and TS 102 821: the distribution interface specifications
4.1.4
DRM+
While DRM currently covers the broadcasting bands below 30 MHz, the DRM consortium
voted in March 2005 to begin the process of extending the system to the broadcasting
bands up to 120 MHz. DRM Plus will be the name of this technology and wider bandwidth
channels will be used, which will allow radio stations to use higher bit rate, thus providing
higher audio quality. One of the new channel bandwidths that is likely to be specified is
50 kHz, which will allow DRM+ to carry radio stations at near CD-quality. The design,
development and testing phases of DRM’s extension, which are being conducted by the
DRM consortium are expected to be completed by 2007-2009. A 100 kHz DRM+
channel has sufficient capacity to carry one mobile TV channel: it would be feasible to
distribute mobile TV too over DRM+ than via either DAB or DVB-H.
voted in March 2005 to begin the process of extending the system to the broadcasting
bands up to 120 MHz. DRM Plus will be the name of this technology and wider bandwidth
channels will be used, which will allow radio stations to use higher bit rate, thus providing
higher audio quality. One of the new channel bandwidths that is likely to be specified is
50 kHz, which will allow DRM+ to carry radio stations at near CD-quality. The design,
development and testing phases of DRM’s extension, which are being conducted by the
DRM consortium are expected to be completed by 2007-2009. A 100 kHz DRM+
channel has sufficient capacity to carry one mobile TV channel: it would be feasible to
distribute mobile TV too over DRM+ than via either DAB or DVB-H.