Patent ID: 6791967
Filing Date: 2004-09-14
Classification: H04J,H04L

Abstract:
A method in a wireless base station that uses time-division duplexing and communicates with a plurality of mobile stations, the wireless base station repeatedly executing a cycle including a reception period and a transmission period, the method comprising the steps of:calculating, during the reception period, a first weight vector for each of the plurality of mobile stations and obtaining transmission signals transmitted by the plurality of mobile stations by weighting signals received by a plurality of antennas using the calculated first weight vectors for the mobile stations; transmitting signals, during the transmission period, which have been weighted using the first weight vectors corresponding to the mobile stations, to the plurality of mobile stations via the plurality of antennas; calculating, from current response vectors of other mobile stations, a second weight vector that has null directivity for the other mobile stations, when the wireless base station detects an error in a signal obtained from an arbitrary mobile station during the reception period in a cycle; and weighting a signal transmitted to the arbitrary mobile station using the second weight vector instead of using the first weight vector and transmitting the weighted signal via the plurality of antennas when the error is detected during the transmission period in the same cycle as the reception period.