System and method for performing weighted processing on down link signal

摘要

A method, device, and communications system for performing weighted processing on a downlink signal are provided. The method includes: acquiring a first CIR from a BS to a relay station and a second CIR from the relay station to a MS; determining a pre-coding weight and a relay weight according to the first CIR and the second CIR; and respectively sending the pre-coding weight and the relay weight to the BS and the relay station, so that the BS is enabled to perform weighted processing on a downlink signal according to the pre-coding weight to obtain a downlink pre-coding weighted signal and send the downlink pre-coding weighted signal to the relay station, and the relay station is enabled to perform weighted processing on the downlink pre-coding weighted signal received by the relay station according to the relay weight to obtain a downlink relay weighted signal and send the downlink relay weighted signal to the MS. Thereby, the downlink signal is optimized at the BS and the relay station respectively, thus optimizing the network capacity and improving the communication quality.

主权项

1. A method for performing weighted processing on a downlink signal, comprising:
acquiring a first Channel Impulse Response (CIR) from a Base Station (BS) of a relay communications system to a relay station of a plurality of relay stations of the relay communication system and a second CIR from the relay station to a Mobile Station (MS); determining a pre-coding weight and a relay weight according to the first CIR and the second CIR; and sending the pre-coding weight to the BS and sending the relay weight to the relay station, so that the BS is enabled to perform weighted processing on a downlink signal according to the pre-coding weight to obtain a downlink pre-coding weighted signal and send the downlink pre-coding weighted signal to the relay station, and the relay station is enabled to perform weighted processing on the downlink pre-coding weighted signal received from the BS according to the relay weight to obtain a downlink relay weighted signal and send the downlink relay weighted signal to the MS, wherein the determining the pre-coding weight and the relay weight according to the first CIR and the second CIR comprises:
determining an initial iteration value of the relay weight and a downlink Signal to Noise Ratio (SINR) threshold,determining an initial iteration value of the pre-coding weight of a time when the downlink SINR threshold is reached and a total transmit power of the BS is minimum according to the initial iteration value of the relay weight, the downlink SINR threshold, the first CIR, and the second CIR,determining an iteration value of the relay weight of a time when the downlink SINR threshold is reached and a total transmit power of the plurality of relay stations is minimum according to the initial iteration value of the pre-coding weight,determining an iteration value of the pre-coding weight of a time when the downlink SINR threshold is reached and the total transmit power of the BS is minimum according to the iteration value of the relay weight, the downlink SINR threshold, and the second CIR,re-determining an iteration value of the relay weight of a time when the downlink SINR threshold is reached and the total transmit power of the plurality of relays stations is minimum according to the iteration value of the pre-coding weight; re-determining an iteration value of the pre-coding weight of a time when the downlink SINR threshold is reached and the total transmit power of the BS is minimum according to the re-determined iteration value of the relay weight, the downlink SINR threshold, and the second CIR; and iterating repeatedly until the minimum total transmit power of the plurality of relay stations converges to a fixed value, anddetermining that an iteration value of the pre-coding weight and an iteration value of the relay weight are respectively the pre-coding weight and the relay weight, where the iteration value of the pre-coding weight and the iteration value of the relay weight are of a time when the minimum total transmit power of the plurality of relay stations converges to a fixed value.