With the launch of 3G technology, there is movement in the mobile TV arena once again. Spencer Kelly has been finding out if it will ever be possible to put a TV in a mobile phone.
Mobile TV has been tried before, never with much success.
3G bandwidth allows users to watch news reports through their mobiles
The thing is, you are faced with the same old problems.
How do you get decent reception when your TV set is constantly on the move?
How do you keep the battery going long enough to watch a long-programme?
And anyway, what kind of programme would you want to watch on a tiny screen?
The truth is, the bar has been set high.
A mobile TV service has to live up to the expectations of the digital TV generation.
Mark Squires, of Nokia, says: "The most important thing to realise about the difference between mobile TV and digital TV is that with digital TV at home you've got an unlimited power supply and a large aerial on the roof of the building, both of which are quite handy."
Screen technology itself has advanced massively in the last few years, making the viewing experience much more enjoyable.
But TV screens are notoriously power hungry.
In mobile versions the backlight and speaker will need to be on throughout the programme.
However, a method called time slicing means that at least the receiver is not on all the time.
Mark Squires says: "Time slicing is a way of making the device's battery last a lot longer because it isn't running all the time.
What's actually happening is that the programme it's receiving is being sent to it in very intense bursts of data, and between those bursts it allows the device to completely shut down, apart, obviously, from the screen and the sound.
To the user it looks like the programme is being received constantly, all the time, but in fact the device is in a sleep state for the majority of the time."
The existing Korean 3G network is fast enough to stream live TV
Receiving the programme in short, high speed bursts means that the signal is received a few seconds before it is needed, and that buffering means that the device can also cope with short breaks in reception.
So if you go under a bridge you will not lose the picture.
Price of success
Korea and Japan are way ahead of the game.
They have been trialling several methods of reception for a couple of years.
The existing Korean 3G network is fast enough to stream live TV.
It is basically broadband TV on your mobile.
Mobile TV user Noh Eun Kyung says: "I first watched TV on my mobile phone when I went fishing.
"I had missed an episode of my favourite TV drama so I began watching it using my phone.
"The TV function is fun and convenient but also very expensive. I only watched about 45 minutes and it cost me about $50."
That is an expensive fishing trip!
Cost, then, will be an important factor in mobile TV's success.
It is generally agreed that content is also an issue. It will not simply be enough to rebroadcast the hundreds of existing channels to mobiles.
Steve Turner, of Philips semiconductors, says: "We are developing specific content for mobile portable devices.
Our expectations with the mobile environment is that you will want a quick fix.
"It won't be plain old TV. It'll be high priority content, whatever your personal profile is.
"It could be sports, could be music, could be anything, but it's something that you would probably not want to wait for."
In Asia, the race for the best mobile TV coverage is on.
SK Telecom will soon launch a rival to the 3G service. Mobile TV broadcast by satellite.
And, because consistency has never featured highly in technology circles, a third method is on its way.
Meanwhile, European trials in Berlin and Helsinki are using existing terrestrial TV masts to broadcast compressed signals to handsets with additional receivers.
All the technical problems appear to have been sorted and now it is all about making the right kind of programmes and making sure people can afford to watch them.
It is on its way, but it will be a little while yet before TV really breaks out of its box.
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