Tuesday, May 15, 2007

Sneak Peek at Cellphone Future


Most of today’s cell phones are 3rd generation cell phone (3G) who promised to transform the speech and message handset into an exciting multimedia tool. That promise has been largely unfulfilled mainly because bandwidths have been limited to between 384 kilobits per second and 2 megabits per second at best. Companies are looking at getting it right with next-generation (4G) technology; in particular one of Japan’s largest mobile phone company, NTT DoCoMo Inc. They have successfully been able to transmit 2.5 GB/s of packet data in a downlink to a vehicle moving at 20Km/h.

The key to make this work is by using the bandwidth more efficiently by using two key technologies: multiple-input-multiple-output (MIMO) and quadrature amplitude modulation (QAM).

MIMO is a data transmission scheme in which different data steams can be sent over the same radio frequency using multiple transmitter and receiver antenna. QAM is a modulation technique that uses variation in signal amplitude to transmit data.

Although the immediate challenges are mostly related to the size of the unit, future technological advances should allow for smaller scale cell phones. The company is looking a wide implementation around 2013. If the technology pans out, the wait could be worth it. Four generation cell phones have the potential to provide a lot more than the current 3G such as realistic videoconferencing, interactive online gaming and high definition video. This new technology would also allow users to access Internet sites without long delays.

No comments: