Mobile Broadcast with DMB, DVB-H and DXB
“Mobile broadcast” is the generic term for systems which provide broadcast and multimedia services for small, portable terminal devices such as mobile phones, pocket TVs, portable radios, etc. The existing digital-broadcast systems DAB and DVB-T, which enable radio and TV reception on the go, belong in the category “mobile broadcast” as do their respective upgraded standards, DMB and DVB-H. Additional examples include mobile communication systems (such as UMTS), which in conjunction with MBMS, for example, also facilitate broadcasting services for third-generation mobile phones.
From a technological perspective, the transmission systems for mobile-broadcast applications in Europe fall into four categories:
- DAB-based systems (e.g. DMB, DXB, BT Livetime)
- DVB-T-based systems (e.g. DVB-H)
- Mobile communication systems (e.g. GPRS, UMTS, S-UMTS, HSDPA, Beyond 3G)
- IT-based systems (e.g. WLAN, WIMAX)
System Comparisons, Expert Advice
IRT takes a neutral approach to assessing these systems. We try out these technologies in field tests and analyse their audio and video quality as well as the transmission control protocols with current and next-generation receivers. IRT helps those designing potential services to select the right technical options and aids in the planning and commissioning of network structures.
In future, content providers will transmit universal services to terminal devices, allowing consumers to use services as they choose - thanks to Mobile API. Advanced functionalities such as the following could thus become reality: recording broadcasts, managing content on receivers by means of metadata, and interacting freely with content providers via return channels. IRT also examines methods such as MPEG-4 LASER, MPEG-4 BIFS, JSR272 and DAB middleware.
DXB - Digital eXtended Broadcasting
The DXB project coordinated by the German Ministry for Education and Research (BMBF) seeks to harmonise DVB-H, DAB/DMB and MBMS so as to prevent fragmentation in the market for multimedia content and receivers. Broadcasting services and content are to be made available via a standard IP interface and various carrier media. This would ensure that content is generated in a uniform manner.
IRT is refining DXB technology to achieve enhanced transmission of audio and video data as well as optimised error control for truly robust reception. A complete DXB transmission chain lays the foundation for not only measuring coverage and bit errors but also a test field for demonstrations.
IRTs Contribution to MIFRIENDS
The Bavarian Regulatory Authority For Commercial Broadcasting (BLM) started the European project MIFRIENDS (German acronym for: mobile, interactive television, radio, interactivity, entertainment and new digital services) to study new, mobile media technologies in and near southern Germany. IRT also provides technological assistance to the Bavarian Broadcasting Network (Bayerischer Rundfunk) and other project partners. And during the 2006 World Cup, IRT broadcast content via its test transmitter in Munich.
Homepage of MIFRIENDS
Image Copyright: BR, Schläger