If you have any queries/comments regarding this web site please email: info at drmradio
dot co dot uk
Welcome to the DRMradio website
International Telecommunications Union (ITU) 2002, International Electrotechnical
Committee (IEC) 2003, and the European Telecommunications Standardisation Institute
(ETSI) 2003, have all approved DRM broadcasts for frequencies below 30 MHz.
As a replacement for AM the existing channel spacing, medium and long wave 9 kHz
and 10 kHz for short wave, is maintained. Audiences for AM radio have declined, most
people will relate to the poor audio quality of AM music.
AM is inefficient in terms of spectrum usage as it requires twice the bandwidth to
transmit audio as the same audio information is contained in both side bands. It
is also inefficient in terms of transmitter power as 50% of the broadcast power goes
into the ‘carrier’. It is not necessary to transmit the carrier although this complicates
the receiver design slightly.
Radio amateurs gave up using AM many decades ago and use Single Side Band (SSB) or
more accurately Single Side Band - Suppressed Carrier. Radio amateurs sometimes refer
to AM as ‘Ancient Modulation’.
When receiving DRM any audio deterioration due to radio propagation fading or interference
is not so evident compared to AM. Providing the DRM decoder software receives enough
digital data correctly then it will be able to accurately rebuild the audio or data
as it was originally coded at the transmitter.
Also the display of the name of the radio station, programme text, and automatic
tuning to alternative frequencies will make DRM receivers easier to operate. DRM
can also transmit multimedia pages and data.
If you listen to a DRM broadcast on an ordinary short wave AM radio then all you
will hear is noise. There is no discernible modulation pattern when listening to
DRM using a AM demodulator.
The Digital Radio Mondiale (DRM) consortium was founded in 1998. Twenty organizations signed a Memorandum of Understanding in Guangzhou, China. These organizations represent broadcasters, academic institutions, and manufacturers. Its purpose is to develop a non-proprietary technical standard for the replacement of analogue AM (Amplitude Modulation) radio with digital radio, also called DRM. [Mondiale is the French word for world].
Not to be confused with the other DRM acronym - Digital Rights Management.