Mobile television is being hailed as the next big thing for anyone with a GSM phone, letting them tune into their favourite program or catch a football match no matter where they are. Only currently available in a few cities in Europe, it could soon become a universal service thanks to a recently standardised technology. Clients and customers are lining up for it.
A European technology, called Digital Video Broadcast – Satellite services to Handheld devices (DVB-SH), will make television broadcasts available to mobile phone users not just in urban areas covered by third-generation (3G) cellular networks, but also in rural areas, where it would be too costly for operators to send a terrestrial signal.
A hybrid solution employing both terrestrial and satellite signals, DVB-SH also offers more bandwidth to allow for more television channels, and, perhaps most importantly, at a lower cost than other available solutions.
In effect, it solves the fundamental problem facing the widespread rollout of mobile TV: how to provide content, efficiently and cost-effectively, to millions of subscribers at the same time within the bandwidth constraints of the already busy radio spectrum.
One-to-many solutions
“Existing mobile cellular technologies are based on the assumption that only a few users want to connect to the same content at the same time. These point-to-point connections work fine for voice, data services and video-on-demand,” says Herbert Mittermayr, vice president of marketing at Alcatel Mobile Broadcast. But television is watched by many people at the same time, with the same content. “For that, you need a broadcast network.”
Mittermayr is overseeing Alcatel’s Unlimited Mobile TV initiative, which aims to start providing mobile TV services to all of Europe from next year. The technology it uses is based in part on the results of the Maestro project, a European Commission-funded initiative that successfully tested a hybrid satellite-terrestrial broadcast system and contributed to the DVB-SH standard. That standard, in turn, is an evolution of another standardised technology, DVB-H, or Digital Video Broadcast – Handheld.
Today, 3G streaming is behind many of the nascent and trial-stage mobile TV services being rolled out in European cities. However, it places the burden for delivering broadcast signals on 3G UMTS networks, which must also use their limited bandwidth for voice and other data communications. A UMTS network, which requires base stations, is also relatively expensive to deploy – and in sparsely populated areas, mobile operators risk never seeing a return on investment.
“In a densely populated area it is easy to cover many subscribers with a few base stations, but in rural areas you might need one base station for only one farm. Return-on-investment is difficult to achieve if the farmer turns out not to be a high-value client,” Mittermayr notes.
Sending signals for less
However, through DVB-SH, a single satellite can provide mobile TV coverage to the whole of Europe. The black spots in urban areas (say where buildings block satellite signals) are covered by repeater stations that can be installed at sites that already exist to provide 3G cellular services, avoiding the hassle of having to install more unpopular and unsightly antennas.
Satellite broadcasts are carried over the S-band, a 30-MHz chunk of Europe’s radio spectrum dedicated to satellite mobile communications that has been unused since its designation 15 years ago even as other segments of the spectrum have rapidly filled up. The S-band has the advantage of being adjacent to the area of the radio spectrum dedicated to 3G mobile communications, meaning that existing antennas on existing sites can be reused.
Further, the S-band frequency is more favourable to the receiver systems in today’s cell phones and PDAs.
Thanks to the use of a similar frequency to 3G it is possible to piggyback DVB-SH on existing infrastructure and “deployment costs are minimised”, confirms Mittermayr. “Operators can save up to 50 percent compared to alternative technologies,” he adds.
With 30MHz of bandwidth available it would be possible to blanket Europe with up to 90 mobile television channels, although Nicolas Chuberre, Maestro’s coordinator at Thales Alenia Space, says 27 channels using only half of the existing spectrum (15 MHz) would be a more realistic number to ensure quality of service initially. “These could cover the whole of Europe providing content in different languages through a clever frequency reuse pattern,” Chuberre explains.
And soon they will.
Thales Alenia Space is currently building a satellite (due to be launched in March 2009) for operators Eutelsat and SES Global to provide mobile TV coverage to Europe. Next year, Alcatel-Lucent plans to start deploying the technology terrestrially over existing UMTS networks, and is currently carrying out evaluations and trials with mobile operators, among them Vodafone, Orange and Telefónica.
In the United States, Alcatel recently signed an agreement with ICO Global Communications to provide its DVB-SH solution. For a standard that is barely six months old, the imminent roll out of commercial systems based on DVB-SH promises a bright future for the technology.
“Analysts are saying that mobile TV will be a big market with more than 100 million subscribers by 2010-2011, each paying 5 euros or more every month. It has the potential to become mobile operators’ biggest revenue driver,” Mittermayr says. “The technology is there to achieve this. What we need now is appealing content for people to enjoy it!”
