Synopsis
We discuss 3G’s background and spectrum allocations, DoCoMo’s FOMA WCDMA system, the Time Division Duplex WCDMA technologies TD-CDMA and TD-SCDMA - the latter being developed by China. We also provide a tutorial on frequency spreading and scrambling, which are the two key techniques underlying CDMA, CDMA2000 and the WCDMA 3G technologies.