Geneva - Sep 2, 2009 - The Digital Radio Mondiale (DRM) system enhancement has been approved by the European Standards Organisation ( ETSI). The DRM system revision v3.1.1 offers two major improvements including the extension to all broadcast bands up to 174MHz and the introduction of MPEG surround support. The DRM system specification was revised to incorporate an additional mode designed for the lower VHF band broadcast frequencies between 30MHz and 174MHz allowing operation in bands I and II (the FM band). This standard enhancement is called DRM+.
The membership vote for the new DRM System Specification (ETSI ES 201 980 v3.1.1) was closed and approved at the end of August by a majority of members, including Russia and the United States. The DRM system specification is available on the ETSI website.
The DRM+ initiative began with a vote at the 2005 General Assembly of the DRM Consortium deciding to extend the standard to higher frequencies. The additional mode for DRM+ was agreed and finalized after testing and verifying the design with both laboratory and field based tests. Then the ETSI standardized DRM system specification was updated.
This extension shares the design philosophy of the DRM standard. Therefore, DRM+ has the same multiplex and signaling scheme, the same OFDM design and the same audio codecs as DRM30 (DRM on broadcast frequencies up to 30MHz). DRM+ is implemented in the standard as robustness mode E. Its spectrum usage parameters are determined from the internationally agreed norms in the FM band (88 to 174MHz). Therefore it has an occupied bandwidth of 95kHz and a frequency grid of 100kHz.