Global mobile operators and device makers are betting that the next level of transmission technology will ramp up mobile phone usage in a way that third-generation technology has so far failed to do.

So-called fourth-generation (4G) mobile technology, now being developed, would allow two-way communication in voice, video and data on a scale that was previously impossible, companies said at a Samsung 4G Forum mobile conference.

4G would allow mobile users on the go to enjoy services that they can now get through personal computers with high-speed broadband connections.

4G is to deliver high-speed broadband for data- and visual- centric information. Everything before 4G is voice-centric, said Ali Tabassi, Sprint Nextel Corp. vice president for innovative technology.

Operators have spent billions of dollars to speed up their mobile networks to offer video, photos, Internet access and other services, which they hope will boost revenues and make up for the lackluster growth of voice calls.

But growth in usage of third-generation (3G) services has been slower than expected.

3G technology, which allows video calls and wireless Internet access, has yet to become widespread and has caused concerns that it may not generate enough profit to justify the amount spent to build the networks.

3G A FAILURE?

3G was a failure, said Kim Ki-ho, Samsung's senior vice president for telecommunications networks. The market did not respond, and it is already becoming an old-fashioned technology.

Others disagree. Kristin Rinne, chief technology officer for Cingular Wireless, said: We're just beginning to hit that exponential curve in terms of data usage (in 3G).

We're going to have to demonstrate we can deliver those products and services to customers. If that doesn't happen, there isn't a need for 4G, Rinne told Reuters.

Japan's NTT DoCoMo Inc. is among a handful of operators that have seen some success with 3G. Users of its 3G service known as FOMA amount to more than 50 percent of its total subscribers.

The International Telecommunication Union (ITU) defines 4G as a wireless technology that transfers data at 100 megabits per second while the user is moving and 1 gigabit per second when stationary.

At the highest speed, users can download a movie in 5.6 seconds and send 100 songs in 2.4 seconds, according to Samsung Electronics Co. Ltd., which presented a 4G service demonstration at the forum.

The spectrum for 4G service will be allocated at a global conference in October next year, and the commercial roll-out is expected after standard-setting around 2010.

After 2010, 4G will become the mobile service that embraces everything, Lee Ki-tae, president of Samsung's telecommunication networks business, told reporters.

Sprint Nextel said earlier this month it would spend up to $3 billion over two years to build a 4G network using WiMax technology, along with Samsung, Motorola Inc. and Intel Corp.

3G was too much technology-driven, said Hong Won-pyo, executive vice president for South Korea-based KT Corp.'s mobile Internet business. From now on, we need to see demand from users grow together (with technology).

Electronics