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Digital Multimedia Broadcasting ('''DMB''') is a Digital Radio Transmission system for sending Multimedia ( Radio , TV , and Datacasting ) to Mobile Device s such as Mobile Phone s. This technology is an offshoot of DAB which was originally developed as a research project for the European Union (Eureka project number EU147). DMB was developed in South Korea under the national IT project and the world's first official DMB broadcast started in South Korea in 2005, although trials were available much earlier. 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 Band s band III ( VHF ) and L ( UHF ), for terrestrial. Because the United States and Canada still Allocate the first band as for television broadcasting (VHF channels 7 to 13) and the United States reserves the L band for military applications, DMB is still unavailable in North America. 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 Convolution al 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 - DQPSK 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 Automobile s. T-DMB is an ETSI standard (TS 102 427 and TS 102 428). DEPLOYMENT Currently, DMB is being put into use in a number of countries, although mainly used in South Korea. South Korea In 2005 , South Korea started S-DMB and T-DMB service on May 1 and December 1 , respectively. [http://www.asiamedia.ucla.edu/article.asp?parentid=34172 As Of December 2006 , T-DMB service in South Korea consists of, 7 TV channels, 12 radio channels, and 8 data channels. These are broadcast on six Multiplex es in the VHF band on TV channels 8 and 12 (6MHz faster). As of April 2007, S-DMB service in South Korea consists of 15 TV channels and 19 radio channels and 3 data 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 System s, Mobile Phone s, Portable Media Player s, Laptop Computer s and Digital Camera s. Today, South Korea has Full T-DMB serviced that include JSS(Jpeg Slide Show),DLS(Dynamic Label Segment),BWS, and TPEG. In Mid August 2007, Iriver, a multimedia and micro-technology company released their "NV", which utilizes South Korea's DMB service. Europe and some other countries Some T-DMB Trial s are currently planned or available around Europe and other countries:
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