DMB - Mobile Television
What is DMB?
Digital Multimedia Broadcasting (DMB) is a video and multimedia technology based on DAB. It offers a wide range of new innovative services, such as mobile TV, traffic and safety information, interactive programmes, data information and many other applications. DMB is currently the world's most successful mobile TV standard, with over 8 million devices sold. Countries in Europe and Asia have implemented commercial services.
Since DMB is based on the globally used digital audio broadcasting (DAB) core standard, DMB devices are always backwards compatible and can receive not only DMB multimedia services but also DAB audio services.
On the broadcaster side, this means that the conventional DAB transmission system can be used for DMB transmission by simply adding a DMB video encoder to the existing DAB system.
Benefits of DMB
- A wide range of TV and interactive services to be broadcast simultaneously on the same multiplex (video services, DAB and DAB+ radio services, file downloading (podcasting), electronic programme guide, slide show, broadcast website, BIFS)
- Exisiting DAB transmitter networkds to be adapted to carry these new services
- Robust reception of mobile TV at highway speeds (>300km/h)
- Multimedia content to be delivered without the risk of network congestion
- Both DMB and DAB services to be accessed on the same receiver
- DMB is an open European Standard
DMB demands less spectrum commitment than other mobile TV standards, which typically use 6-8 MHz blocks. In contrast, DMB can offer both TV and radio services within a multiplex of just 1.5 MHz. Whilst this spectrum would deliver a range of approximately 7 DMB services, extra services can be made available simply by adding further multiplexes.
DMB has the further benefit of being broadcast in Band III or L-Band, where higher powers give rise to broader and more comprehensive coverage. Other mobile TV standards must use UHF Bands IV or V. As a result, transmitter powers are low and coverage areas from a single transmitter are typically small. However, since DMB is in Band III and L-Band higher powers give rise to broader and more comprehensive coverage.
Success of DMB
With the addition of the video application DMB, the WorldDMB forum has seen remarkable growth and interest throughout the industry. On 1st December 2005 Korea became the first country to ever launch a consumer facing mobile TV service. This was done via DMB. In Europe, Germany soon followed suit with DMB mobile TV services launched to coincide with the 2006 FIFA World Cup. The technology has since proven popular on a worldwide scale: 14 European countries and 9 further countries have carried out test or trials. These include: Australia, the Czech Republic, Denmark, France, Ghana, Indonesia, Italy, Kuwait, Luxembourg, Malaysia, Malta, the Netherlands, New Zealand, Norway, Portugal, Singapore, South Africa, Spain, Sweden, Switzerland and the UK.
Read a detailed account on how DMB works or visit www.t-dmb.org for more information.