Digital Radio Mondiale (DRM; ''mondiale'' being
Italian
Italian(s) may refer to:
* Anything of, from, or related to the people of Italy over the centuries
** Italians, an ethnic group or simply a citizen of the Italian Republic or Italian Kingdom
** Italian language, a Romance language
*** Regional Ita ...
and
French for "worldwide") is a set of
digital audio broadcasting
Digital radio is the use of digital technology to transmit or receive across the radio spectrum. Digital transmission by radio waves includes digital broadcasting, and especially digital audio radio services.
Types
In digital broadcasting sy ...
technologies designed to work over the bands currently used for analogue radio broadcasting including
AM broadcasting
AM broadcasting is radio broadcasting using amplitude modulation (AM) transmissions. It was the first method developed for making audio radio transmissions, and is still used worldwide, primarily for medium wave (also known as "AM band") transm ...
—particularly
shortwave—and
FM broadcasting
FM broadcasting is a method of radio broadcasting using frequency modulation (FM). Invented in 1933 by American engineer Edwin Armstrong, wide-band FM is used worldwide to provide high fidelity sound over broadcast radio. FM broadcasting is cap ...
. DRM is more spectrally efficient than AM and FM, allowing more stations, at higher quality, into a given amount of
bandwidth
Bandwidth commonly refers to:
* Bandwidth (signal processing) or ''analog bandwidth'', ''frequency bandwidth'', or ''radio bandwidth'', a measure of the width of a frequency range
* Bandwidth (computing), the rate of data transfer, bit rate or thr ...
, using
xHE-AAC
Unified Speech and Audio Coding (USAC) is an audio compression format and codec for both music and speech or any mix of speech and audio using very low bit rates between 12 and 64 kbit/s. It was developed by Moving Picture Experts Group (MPEG ...
audio coding format
An audio coding format (or sometimes audio compression format) is a content representation format for storage or transmission of digital audio (such as in digital television, digital radio and in audio and video files). Examples of audio coding ...
. Various other
MPEG-4 and
Opus
''Opus'' (pl. ''opera'') is a Latin word meaning "work". Italian equivalents are ''opera'' (singular) and ''opere'' (pl.).
Opus or OPUS may refer to:
Arts and entertainment Music
* Opus number, (abbr. Op.) specifying order of (usually) publicatio ...
codecs are also compatible, but the standard now specifies
xHE-AAC
Unified Speech and Audio Coding (USAC) is an audio compression format and codec for both music and speech or any mix of speech and audio using very low bit rates between 12 and 64 kbit/s. It was developed by Moving Picture Experts Group (MPEG ...
.
Digital Radio Mondiale is also the name of the international
non-profit
A nonprofit organization (NPO) or non-profit organisation, also known as a non-business entity, not-for-profit organization, or nonprofit institution, is a legal entity organized and operated for a collective, public or social benefit, in co ...
consortium that has designed the platform and is now promoting its introduction.
Radio France Internationale
Radio France Internationale, usually referred to as RFI, is the state-owned international radio broadcaster of France. With 37.2 million listeners in 2014, it is one of the most-listened-to international radio stations in the world, along with ...
,
TéléDiffusion de France
TDF (which stands for ''Télédiffusion de France'' officially renamed ''TDF'' in 2004) is a French company which provides radio and television transmission services, services for telecommunications operators, and other multimedia services ...
,
BBC World Service,
Deutsche Welle,
Voice of America
Voice of America (VOA or VoA) is the state-owned news network and international radio broadcaster of the United States of America. It is the largest and oldest U.S.-funded international broadcaster. VOA produces digital, TV, and radio content ...
,
Telefunken
Telefunken was a German radio and television apparatus company, founded in Berlin in 1903, as a joint venture of Siemens & Halske and the ''Allgemeine Elektrizitäts-Gesellschaft'' (AEG) ('General electricity company').
The name "Telefunken" ap ...
(now
Transradio) and Thomcast (now
Ampegon) took part at the formation of the DRM consortium.
The principle of DRM is that bandwidth is the limiting factor, and computer processing power is cheap; modern
CPU-intensive audio compression techniques enable more efficient use of available bandwidth, at the expense of processing resources.
Features
DRM can broadcast on frequencies below 30 MHz (
long wave
In radio, longwave, long wave or long-wave, and commonly abbreviated LW, refers to parts of the radio spectrum with wavelengths longer than what was originally called the medium-wave broadcasting band. The term is historic, dating from the e ...
,
medium wave and
short wave), which allow for very-long-distance signal propagation. The modes for these lower frequencies were previously known as "DRM30". In the
VHF bands, the term "DRM+" was used. DRM+ is able to use available broadcast spectra between 30 and 300 MHz; generally this means
band I (47 to 68 MHz),
band II (87.5 to 108 MHz) and
band III (174 to 230 MHz). DRM has been designed to be able to re-use portions of existing analogue
transmitter
In electronics and telecommunications, a radio transmitter or just transmitter is an electronic device which produces radio waves with an antenna. The transmitter itself generates a radio frequency alternating current, which is applied to the ...
facilities such as antennas, feeders, and, especially for DRM30, the transmitters themselves, avoiding major new investment. DRM is robust against the fading and interference which often plague conventional broadcasting in these frequency ranges.
The encoding and decoding can be performed with
digital signal processing, so that a low-cost
embedded system
An embedded system is a computer system—a combination of a computer processor, computer memory, and input/output peripheral devices—that has a dedicated function within a larger mechanical or electronic system. It is ''embedded'' ...
with a conventional transmitter and receiver can perform the rather complex encoding and decoding.
As a digital medium, DRM can transmit other data besides the audio channels (
datacasting
Datacasting (data broadcasting) is the broadcasting of data over a wide area via radio waves. It most often refers to supplemental information sent by television stations along with digital terrestrial television (DTT), but may also be applied ...
) — as well as
RDS-type
metadata or
program-associated data Program Associated Data (PAD) or Program Service Data (PSD) is the data displayed on many HD Radio and satellite radio receivers. It can describe the program being transmitted and other information such as the name of the song, the artist and the ge ...
as
Digital Audio Broadcasting
Digital radio is the use of digital technology to transmit or receive across the radio spectrum. Digital transmission by radio waves includes digital broadcasting, and especially digital audio radio services.
Types
In digital broadcasting sy ...
(DAB) does. DRM services can be operated in many different network configurations, from a traditional
AM one-service one-transmitter model to a multi-service (up to four) multi-transmitter model, either as a
single-frequency network
A single-frequency network or SFN is a broadcast network where several transmitters simultaneously send the same signal over the same frequency channel.
Analog AM and FM radio broadcast networks as well as digital broadcast networks can operate ...
(SFN) or
multi-frequency network Data networks, such as wireless communication networks, have to trade off between services customized for a single terminal and services provided to a large number of terminals. For example, the distribution of multimedia content to a large number o ...
(MFN). Hybrid operation, where the same transmitter delivers both analogue and DRM services simultaneously is also possible.
DRM incorporates technology known as Emergency Warning Features that can override other programming and activates radios which are in standby in order to receive emergency broadcasts.
Status
The technical standard is available free-of-charge from the
ETSI, and the
ITU
The International Telecommunication Union is a specialized agency of the United Nations responsible for many matters related to information and communication technologies. It was established on 17 May 1865 as the International Telegraph Unio ...
has approved its use in most of the world. Approval for
ITU region 2 is pending amendments to existing international agreements. The inaugural broadcast took place on June 16, 2003, in
Geneva
, neighboring_municipalities= Carouge, Chêne-Bougeries, Cologny, Lancy, Grand-Saconnex, Pregny-Chambésy, Vernier, Veyrier
, website = https://www.geneve.ch/
Geneva ( ; french: Genève ) frp, Genèva ; german: link=no, Genf ; it, Ginevr ...
,
Switzerland, at the ITU's
World Radio Conference
In its most general sense, the term "world" refers to the totality of entities, to the whole of reality or to everything that is. The nature of the world has been conceptualized differently in different fields. Some conceptions see the worl ...
.
Current broadcasters include
All India Radio
All or ALL may refer to:
Language
* All, an indefinite pronoun in English
* All, one of the English determiners
* Allar language (ISO 639-3 code)
* Allative case (abbreviated ALL)
Music
* All (band), an American punk rock band
* ''All'' (All ...
,
BBC World Service,
funklust (formerly known as BitXpress),
Radio Exterior de España
Radio Exterior de España (REE) or simply Radio Exterior is a Spanish free-to-air radio station owned and operated by Radio Nacional de España (RNE), the radio division of state-owned public broadcaster RTVE, Radiotelevisión Española (RTVE). I ...
,
Radio New Zealand International
RNZ Pacific or Radio New Zealand Pacific, sometimes abbreviated to RNZP, is a division of Radio New Zealand and the official international broadcasting station of New Zealand. It broadcasts a variety of news, current affairs and sports programme ...
,
Vatican Radio
Vatican Radio ( it, Radio Vaticana; la, Statio Radiophonica Vaticana) is the official broadcasting service of Vatican City.
Established in 1931 by Guglielmo Marconi, today its programs are offered in 47 languages, and are sent out on short wave, ...
,
Radio Romania International
Radio România Internaţional ( ro, Radio România Internaţional, or ) is a Romanian radio station owned by the Romanian public radio broadcaster Societatea Română de Radiodifuziune (SRR, the national public radio in Romania) that broadcasts ...
and Radio Kuwait.
Until now DRM receivers have typically used a
personal computer
A personal computer (PC) is a multi-purpose microcomputer whose size, capabilities, and price make it feasible for individual use. Personal computers are intended to be operated directly by an end user, rather than by a computer expert or tec ...
. A few manufacturers have introduced DRM receivers which have thus far remained niche products due to limited choice of broadcasts. It is expected that the transition of national broadcasters to digital services on DRM, notably All India Radio, will stimulate the production of a new generation of affordable, and efficient receivers.
Chengdu NewStar Electronics is offering the DR111 from May 2012 on which meets the minimum requirements for DRM receivers specified by the DRM consortium and is sold worldwide.
The General Overseas Service of
All India Radio
All or ALL may refer to:
Language
* All, an indefinite pronoun in English
* All, one of the English determiners
* Allar language (ISO 639-3 code)
* Allative case (abbreviated ALL)
Music
* All (band), an American punk rock band
* ''All'' (All ...
broadcasts daily in DRM to Western Europe on 9.95 MHz at 17:45 to 22:30 UTC.
All India Radio
All or ALL may refer to:
Language
* All, an indefinite pronoun in English
* All, one of the English determiners
* Allar language (ISO 639-3 code)
* Allative case (abbreviated ALL)
Music
* All (band), an American punk rock band
* ''All'' (All ...
is in the process of replacing and refurbishing many of its domestic AM transmitters with DRM. The project which began in 2012 is scheduled to complete during 2015.
The British Broadcasting Corporation
BBC #REDIRECT BBC #REDIRECT BBC
Here i going to introduce about the best teacher of my life b BALAJI sir. He is the precious gift that I got befor 2yrs . How has helped and thought all the concept and made my success in the 10th board exam. ...
...
. Th
lasted for a year (April 2007 – April 2008).
The
...