Radio base station and method of controlling radio communications

摘要

The present invention provides a radio base station using the conventional downlink transmit diversity which can compensate for the degradation of transmission quality even when a plurality of users (mobile terminals) share a single time slot using a code division multiple system. The radio base station includes a channel estimator(16) for performing channel estimation of an uplink time slot; a transmit diversity controller (141 to 14N) for controlling the transmit diversity used for downlink time slots(DL#1 to DL#N) based on said channel estimation and the number of users sharing the downlink time slot when using a code division multiple system; a data transmitter (15) for transmitting data via downlink time slots (DL#1 to DL#N) using the controlled transmit diversity.