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Mobile TV gives a new view of Games

Apple may be doing well selling downloadable TV shows for viewing on iPods, but the world-first technology being demonstrated by Telstra and Microsoft at Melbourne's Commonwealth Games could soon knock the download-and-watch model on its head.

Apple may be doing well selling downloadable TV shows for viewing on iPods, but the world-first technology being demonstrated by Telstra and Microsoft at Melbourne's Commonwealth Games could soon knock the download-and-watch model on its head.

Telstra representatives have fanned the city demonstrating 75 eTEN M600 Pocket PCs that can tune into any of seven video channels carrying live, unedited Channel 9 video feeds of Games events as they happen. In a world-first display of the technology's potential, there is also a data channel carrying up-to-the-minute event results, schedules and other information. The handhelds have been available for public viewing at the Telstra Discovery Centre in Melbourne's Birrarung Marr during the course of the Games and have aroused considerable interest from passers-by.

The video channels are encoded using Windows Media 10 in real time, then broadcast over conventional UHF TV frequencies (in the 578 MHz band, next to conventional station Channel 31) across the city of Melbourne. Digitised video uses a high-bandwidth signal following the DVB-H (Digital Video Broadcasting-Handheld) video standard. Because the system operates in conventional TV frequencies, range is measured in tens of kilometres.

The eTEN M600s run on Microsoft's Windows Mobile 5 operating system and tune in using purpose-built software and DiBcom expansion cards that fit into a handheld PC's SDIO slot, allowing users to pick the channel they want and view high-quality, 25fps video in landscape mode.

Over the past year, DVB-H technology has been tested in Sydney and around the world for delivery of pre-encoded content. However, the Games trial marks the first time the technology has been used to simultaneously encode and broadcast multiple video channels and data information in real time. That's a big step forward given that a major market for such technology is the broadcasting of live sports events.

Broadcasts were not without their problems: the demonstration unit CNET Australia observed had some trouble locking in a signal from a café in inner-city Richmond, approximately 4km from the transmitter. Rob Spaits, senior emerging technology specialist with Telstra and the man behind the current trial, attributes this to the tight power level restrictions placed on the current trial, and says a properly amped-up broadcast signal would have blanketed much of the city and suburbs with up to around 14 video channels.


When the signal did work, however, the video was impressive: quite smooth and very watchable, it well demonstrated the potential appeal of DVB-H for bringing live video to handhelds. Broadcasts of game venues were sharp and detailed given the screen size; on a sample channel with a live feed of the colourful beach boxes and Brighton Beach, the detail of small waves was clearly visible.

Technical issues could quickly grow DVB-H to become more than just a novelty. The current most popular method of distributing videos to mobiles - as downloads via third-generation mobile networks - was recently called into question by UK research firm Analysys, which said 3G networks could run out of bandwidth by 2007 if 40 percent of their subscribers watched just eight minutes of video a day.

DVB-H, by contrast, uses a completely different set of radio spectrum and a one-way broadcast delivery method that is not constrained in the same ways as session-based 3G services. That has made it a popular target for mobile service providers, who have tested DVB-H based mobile TV services in numerous overseas trials. Nokia, Motorola, Siemens, Samsung and other mobile manufacturers are working with Microsoft and chipmakers like Broadcom and Intel to integrate DVB-H chips into their devices.

Mass-market availability of the technology would enable commercially viable pay-per-view subscription models: access to specific DVB-H content can be limited using Windows Media's built-in digital rights management capabilities, so it would be relatively easy to order a sporting event and have it charged to your mobile bill. That would make it a more than capable delivery platform to improve coverage of one-off sporting events and provide consumers with live music downloads, pay-per-view movies, and other content.

The technology is ready, says Spaits, who believes the real obstacles to adoption will come from other quarters - particularly the government, which last week released a controversial digital TV policy that favours existing commercial networks and supports the regulation of upcoming IPTV services - a category that would technically include DVB-H.

"The biggest hurdle to these services is going to be legislation," he explains. "We're hoping this trial will generate the sort of interest in the technology to ensure that when politicians look at legislation, they think about more than just digital TV."