Digital Multimedia Broadcasting

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For other uses, see DMB (disambiguation).

Digital Multimedia Broadcasting (DMB) is a digital radio transmission system for sending multimedia (radio, TV, and datacasting) to mobile devices such as mobile phones. It can operate via satellite (S-DMB) or terrestrial (T-DMB) transmission. DMB is based on the Eureka 147 Digital Audio Broadcasting (DAB) standard, and has some similarities with the main competing mobile TV standard, DVB-H.

Like DAB, T-DMB is made for transmissions on radio frequency bands band III (VHF) and L (UHF), mainly for terrestrial and satellite, respectively. Because the United States has so far failed to allocate these two bands as most of the rest of the world has, DMB is still unavailable there. Qualcomm's MediaFLO is a proprietary system used there instead. In Japan, 1seg is the standard, using ISDB.

T-DMB uses MPEG-4 Part 10 (H.264) for the video and MPEG-4 Part 3 BSAC or HE-AAC V2 for the audio. The audio and video is encapsulated in MPEG-2 TS. The stream is RS encoding and the parity word is 16 bytes length. There is convolutional interleaving made on this stream, then the stream is broadcast in data stream mode on DAB. In order to diminish the channel effects such as fading and shadowing, DMB modem uses OFDM-4DPSK modulation. A single-chip T-DMB receiver is also provided by an MPEG-2 transport stream demultiplexer. DMB has several applicable devices such as mobile phone, portable TV, PDA and telematics devices for automobiles.

T-DMB is an ETSI standard (TS 102 427 and TS 102 428).

1 Deployment
- 1.1 South Korea
- 1.2 Europe and some other countries
2 See also
3 External links

[edit] Deployment

Currently, DMB is being put into use in a number of countries.

[edit] South Korea

In 2005, South Korea started S-DMB and T-DMB service on May 1 and December 1, respectively. [1] [2]

As of April 2006, T-DMB service in South Korea consists of, 7 TV channels, 13 radio channels, and 8 data channels. These are broadcast on six multiplexes in the VHF band on TV channels 8 and 12 (6MHz raster).

As of April 2006, S-DMB service in South Korea consists of 7 TV channels and 20 radio channels.

S-DMB service in South Korea is provided on a subscription basis through TU Media and is accessible throughout the country. T-DMB service is provided free of charge, but access is limited in selected regions.

Around one million receivers have been sold as of June 2006. Receivers are integrated in car navigation systems, mobile phones, personal video players, laptop computers and personal digital cameras.

[edit] Europe and some other countries

Some T-DMB trials are currently planned around Europe:

Germany will launch a T-DMB commercial service for the World Cup 2006
France is currently running a trial in Paris
Switzerland and Italy have prepared for trials in 2006
China and the UK have planned launches of commercial services for middle of 2006
Indonesia is currently running a trial in Jakarta