W-CDMA terminal

摘要

We have developed a W-CDMA (wideband code-division multiple access) terminal for IMT-2000 (International Mobile Telecommunication 2000) field experiments. Although many efforts are ongoing to merge candidate systems, we selected the 1997 versionW-CDMA from ARIB.For multimedia functions, an 1.430 interface was installed and an MPEG-4(Moving Picture Experts Group-4)-based moving picture terminal was connected to realize a mobile TV-phone. Two problems were encountered: how to realize a giant-scale digital circuit, and how to realize a 2 GHz low-distortion power amplifier. In response to these problems, we developed four LSIs and constructed a digital circuit with these LSIs together with a digital signal processor (DSP) and field programmable gate arrays (FPGAs).We also developed a power amplifier with a feed-forward type linearizer.Although the terminal is currently large in size (approximately 20 liters), it can be used for field experiments. We expect this terminal to contribute to the development of IMT-2000 systems.