Mobile television – what's happening?

Watching video clips on your mobile phone is nothing new, but some technologies waiting in the wings promise to turn your handset into a fully fledged television set.

Rather than being restricted to short viewing sessions and a limited number of programs, the technologies will let you watch for as long as you wish, and choose from a large number of channels.

Such services are already being rolled out overseas and, if a few regulatory hurdles can be overcome, they may soon be available in Australia.

With Nokia poised to launch its anticipated N96 that includes DVB-H capabilities, will it be a case of "sell them and they will come" for the television operators? (Credit: Nokia)

Competing standards
As is often the case in the world of technology, there are a variety of competing standards when it comes to getting television onto you mobile. Each has its backers and all are vying to be the final choice. But, just as VHS won over Beta and Blu-ray saw off HD-DVD, in the end it's likely there will be just one winner.

The main contenders are:

• DVB-H (Digital Video Broadcasting for Handhelds)
  

Backed by handset heavyweight Nokia and a range of European mobile carriers, DVB-H works in the same way as existing digital television services. Signals are broadcast from towers direct to compatible handsets, bypassing the mobile phone networks altogether.

Proponents say the system is best because it is not constrained by the capacity of the networks. So, if thousands of people want to watch a sporting event at the same time, the system can deliver them good-quality video and sound.

The downside is that the service requires the allocation of a chunk of radio spectrum and the installation of new broadcast equipment.

• MBMS (Multimedia Broadcast Multicast Service)
  

Backed by Ericsson and another group of mobile carriers, MBMS piggybacks on existing mobile networks. Video is carried over the network in the same way as phone calls and delivered to compatible handsets.

MBMS-enabled networks actively monitor the number of subscribers viewing particular feeds. When the number rises above a pre-determined level, the streams are switched automatically from uni-cast (one-to-one transmission) to a broadcast feed sent over the mobile network. That way, large numbers of viewers can be catered for without running into network capacity limits.

One big advantage of MBMS technology for mobile operators is that it requires only a software upgrade to their existing 3G networks. This does away with the need for extra radio spectrum and broadcast equipment.

• MediaFLO (Media Forward Link Only)
  

A third alternative, created by US-based Qualcomm, uses a broadcast technique similar to that of DVB-H. However, rather than making it an open standard, the company has opted for a closed shop. In the US, the company has been busy acquiring its own radio spectrum and building its own network, keeping the whole thing very close to its corporate chest.

According to Qualcomm, MediaFLO can offer more choice for users because the compression techniques used mean more channels can be broadcast in a given chunk of spectrum.

Industry watchers expect that the technology will prove popular in the US, but remain less convinced of its potential for success in other parts of the world.