| Satellite radio systems are actually part of a larger | | | | transmission. Since the wider spectrum of broadcasts |
| group of broadcasting mediums, which specialists | | | | has to be covered, digital multimedia broadcasting |
| refer to as Digital Multimedia Broadcasting or DMB. | | | | uses OFDM-4DPSK modulation and a chip of T-DMB |
| This digital transmission system is used in order to | | | | receiver is also provided by MPEG-2 Transport |
| send data to different receivers such as radios, | | | | Stream De-multiplexer. This helps reduce the negative |
| television sets or mobile phones and PDAs. There are | | | | effects of shadowing and fading, present in many |
| two different ways of using digital multimedia | | | | digital transmissions. |
| broadcasting - S-DMB which is broadcasting via a | | | | The future of digital multimedia broadcasting |
| satellite or T-DMB which uses terrestrial emitters. The | | | | The transfer from the analog world to the digital one |
| complexity of the entire digital multimedia | | | | is obvious in all fields of work. Since digital multimedia |
| broadcasting field is huge. Out of all the features and | | | | broadcasting is developing so quickly, there is a silent |
| characteristics digital broadcasting offers, satellite | | | | battle going on between the new age digital |
| radio is probably the most spectacular as it generated | | | | technology and the classic analog one. OF course, |
| immense interest and triggered an intense | | | | many compare the transition from the analog to the |
| competition between the two main satellite radio | | | | completely digital era with the way audio cassettes |
| broadcasters, Sirius and XM Radio. The development | | | | were replaced by CDs and later on even DVDs. |
| of satellite radio and other forms of digital | | | | However, the development of digital multimedia |
| broadcasting is spectacular because it offers two | | | | broadcasting is slower since it happens on so many |
| main qualities that terrestrial emitters are deficient in: | | | | levels at the same time. Digital television is taking us |
| quality and coverage. In the case of satellite radio, | | | | into new spaces that are basically hybrids of the |
| for example, the sound quality from a satellite | | | | features of regular TV and characteristics of the |
| broadcast is much higher than AM or FM broadcasts, | | | | Internet. Satellite radio is also taking huge leaps |
| as the hissing noises and transmission disturbances | | | | forward, with more and more programs having |
| are eliminated. | | | | satellite radio exclusivity. There are even discussion of |
| Technical features of digital multimedia broadcasting - | | | | moving events like the MLB exclusively on satellite |
| overview | | | | radio, which would provide one of the first deadly |
| Whether it refers to television, satellite radio or cell | | | | strikes against terrestrial radio broadcasting. Digital |
| phone transmissions, digital multimedia broadcasting is | | | | data transmission is fast and accurate, and so far |
| based on the Eureka 147 DAB standard. Digital | | | | reality proves that the satellites used in order to |
| television uses the T-DMB which is made for | | | | facilitate broadcasting and reliable. Most digital |
| transmissions on frequency bands III (VHF) and L | | | | multimedia broadcasting companies that own satellites |
| (SHF). T-DMB is an ETSI standard (TS 102 427 and | | | | also have backup ones ready to go in orbit and |
| TS 102 428). | | | | replace a defective one. Some other benefits of |
| T-DMB uses MPEG-4 Part 10 (H264) for the video | | | | digital multimedia broadcasting recommend it as a |
| and MPEG-4 Part 3 BSAC or HE-AAC V2 for the | | | | next step in the development of broadcasting. From |
| audio. When it comes to satellite radio, there were | | | | the consumer's point of view, the quality and |
| a few issues to be resolved by the main satellite | | | | interactivity options of digital TV or satellite radio |
| radio broadcasters. The satellite radio receiver needs | | | | broadcasts are important features. Although most |
| to be in the line of sight of the satellite to receive | | | | digital multimedia broadcasting channels and |
| the transmission - and there is the problem of having | | | | technologies are still complex and sometimes |
| different landscaping objects block the direct | | | | expensive, the evolution of digital broadcasting seems |
| transmission. Land based devices were installed in | | | | to be here to stay. |
| order to eliminate the lack of direct satellite | | | | |