The range of features on your mobile phone already goes well beyond nattering to your friends. Now, another could be on the way – TV on your phone.

Mobile phone manufacturers and network operators around the globe are banking on mobile TV taking off. The surge in interest comes as the mobile industry explores new ways to generate revenue beyond its cash-cow telephony business. For sure, mobile TV could be a new money spinner, provided the technology works and the service is affordable. Early developments are encouraging.

For those not familiar with mobile TV, the service has two primary and potentially competing distribution channels. With one, mobile phones receive regular TV broadcasts using special antennas. With the other, the signal is transmitted over the mobile network as a stream of video data. The big difference between the two is broadcast's one-to-many relationship versus mobile's one-to-one.

The broadcast technology isn't entirely new. Some countries, notably Japan and South Korea, have been working on it for the past few years. Unfortunately, each has developed its own standard. That's a problem for the global mobile market.

The Japanese format, called ISDB-T (Integrated Services Digital Broadcasting - Terrestrial), is still undergoing field tests. The South Korean format, DMB (Digital Media Broadcasting), is featured in a phone that LG unveiled in November. Rival Samsung is following with its own DMB-enabled phone.

The US’ broadcasting standard ATSC (Advanced Television Systems Committee) lacks a mobile component. Qualcomm is trying to fill that void with its own proprietary MediaFLO (Forward Link Only) multicasting technology – an alternative to digital broadcasting.

Broadcast standards

The technology, which would also accommodate the streaming of content over 3G networks, transmits in the 700MHz range and requires 30 to 50 times fewer towers than a cellular network. Qualcomm has announced plans to provide a chip that promises playback at up to 30fps.

A European format, DVB-H (Digital Video Broadcasting - Handheld), also appears to be gaining traction. Last year, Finnish mobile phone maker Nokia and cell-tower operator Crown Castle began trials of the technology in Pittsburgh.

Indeed, DVB-H has the potential to become a global standard, which, in turn, could help drive down production costs. The format is backed by some of the world's largest handsets makers, including Motorola, NEC, Nokia, Siemens, and Sony Ericsson. The European Telecommunications Standards Institute (ETSI) selected it as a standard in November.

The DVB-H standard has addressed – and largely resolved – two problems plaguing mobile TV: frame rates and battery life, according to Jouni Kämäräinen, director of rich media technology at Nokia. The standard, he says, supports rates of up to 25fps, compared to earlier formats that ranged from one to five. By comparison, standard TV broadcasts have rates of between 25 and 30fps.

As for battery life, DVB-H temporarily shuts off tuner chips between broadcast bursts, a technique known as time slicing. The result is a huge increase in battery life, according to Kämäräinen. "In our pilots, we have achieved up to four hours of uninterrupted TV viewing, compared with 15 to 30 minutes with other technology," he said.

Channel hopping

Nokia has been testing broadcast mobile TV with its new model 7710 smart phone and an attachable DVB-H receiver. The company is also developing models that will integrate the receiver into the handset.

Phones equipped with DVB-H receivers have a few advantages. For example, many users in one spot, say a football stadium, can receive the same signal simultaneously. That makes live coverage relatively easy. The broadcast service can also support more than 30 channels.

Perhaps the only significant drawback of DVB-H is cost. Digital broadcasters must invest in new hardware and software to build a network that supports this standard, in addition to securing licensed spectrum, according to Mark Heath, an analyst with Analysys.

That's going to take some time. Analyst group Gartner says it doesn't expect real-time mobile TV services to be commercially available in Europe until 2007 at the earliest.

This gap, however, could be an opportunity for mobile operators. "While digital broadcasters carefully weigh an investment in DVB-H, 3G operators could push their video streaming services," Heath said.

In Europe, several operators are doing just that, including Hutchison 3G, Vodafone, and Mobilkom Austria.

In the US, Verizon Wireless and Sprint have launched similar forms of mobile TV service.

Television networks

Mobile TV delivered over a cellular network has a couple of advantages, according to Heath. First, many new 3G networks are now up and running, and desperate for business, he says. Second, they are well suited for providing chunks of content on demand – watching condensed news programs whenever you want, for example. And finally, from an operator's perspective, a sophisticated back-end billing system can easily manage payments for premium content.

And the disadvantages? There seems to be really only one, but it could be significant: capacity.

If several hundred customers want to watch streamed video content in roughly the same area at the same time, their mobile phone operator must provide sufficient network capacity, which is costly.

"If mobile TV becomes really popular, which is possible, then both the broadcast and video streaming channels will be necessary and can complement each other," Heath says. "Customers could use the broadcast service to watch a live sports game and the video streaming service to download a music clip or an entertainment program on demand."

Even if mobile TV is being hyped by the mobile phone industry as the next big application, users will ultimately determine its success. Which brings us to the issue of screen size. Frame rates and resolution are improving but images are – and will remain – difficult to make out and uncomfortable to view for long periods on a small screen.

That's why some mobile operators see the future of mobile TV not in movies or entire shows but in condensed content streamed to handsets on demand. "I'm keen to watch 30 seconds or two minutes or even four minutes of news or sports or a video clip, but I'm not going to watch a movie or soap opera on a small screen," said Boris Nemsic, CEO of Mobilkom Austria. "It's just too hard on my eyes."

Pricing, too, will be critical. Consumers may balk at fees that add up quickly on top of their monthly bill.

Where the nascent market for mobile TV is headed is anyone's guess. But one thing is certain: it's gaining momentum – so stay tuned.