The launch of third-generation cellphone systems nearly five years ago promised to transform the speech-and-message handset into an exciting multimedia tool. It is a promise largely unfulfilled. But network operators are looking ahead -- admittedly rather far ahead -- to get things right with next-generation (4G) technology: it will be an all-packet service that integrates voice and data transmitted at high speeds and capacities. With an eye to 4G, Japan's largest mobile phone company, NTT DoCoMo Inc., has successfully transmitted 2.5 Gb/s of packet data in a downlink to a vehicle moving at 20 kilometers per hour. Though the equipment in the vehicle is about the size of a refrigerator, at least the principle is demonstrated.
See "Sneak Peek at Cellphone Future," by John Boyd: http://www.spectrum.ieee.org/jun06/3672
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