A method for use in a communication system, wherein the communication system comprises three base stations (BS1, BS2 and BS3) adjacent to each other, each base station serving at least one user equipment UE (MS1, MS2 and MS3), the method comprises: acquiring, by each base station, channel matrices of channels between any two adjacent base stations; and calculating an interference alignment-based transmission precoding matrix for each base station based on the channel matrices of the channels between the base stations; wherein interferences to a base station from two base stations adjacent to the base station are aligned to an identical sub-space; characterized in that the method further comprises: acquiring an instantaneous downlink channel matrix and instantaneous downlink channel quality information of a channel from each base station to one of the at least one UE which the base station serves; multiplying the instantaneous downlink channel matrix by the interference alignment-based transmission precoding matrix, so as to obtain an equivalent channel matrix; optimizing the interference alignment-based transmission precoding matrix based on the equivalent channel matrix and the instantaneous downlink channel quality information according to a predetermined optimization criterion, so as to obtain an optimized interference alignment-based transmission precoding matrix; and precoding the data to be transmitted using the optimized interference alignment-based transmission precoding matrix. acquiring, by each base station, channel matrices of channels between any two adjacent base stations; and calculating an interference alignment-based transmission precoding matrix for each base station based on the channel matrices of the channels between the base stations; wherein interferences to a base station from two base stations adjacent to the base station are aligned to an identical sub-space; characterized in that the method further comprises: acquiring an instantaneous downlink channel matrix and instantaneous downlink channel quality information of a channel from each base station to one of the at least one UE which the base station serves; multiplying the instantaneous downlink channel matrix by the interference alignment-based transmission precoding matrix, so as to obtain an equivalent channel matrix; optimizing the interference alignment-based transmission precoding matrix based on the equivalent channel matrix and the instantaneous downlink channel quality information according to a predetermined optimization criterion, so as to obtain an optimized interference alignment-based transmission precoding matrix; and precoding the data to be transmitted using the optimized interference alignment-based transmission precoding matrix. acquiring an instantaneous downlink channel matrix and instantaneous downlink channel quality information of a channel from each base station to one of the at least one UE which the base station serves; multiplying the instantaneous downlink channel matrix by the interference alignment-based transmission precoding matrix, so as to obtain an equivalent channel matrix; optimizing the interference alignment-based transmission precoding matrix based on the equivalent channel matrix and the instantaneous downlink channel quality information according to a predetermined optimization criterion, so as to obtain an optimized interference alignment-based transmission precoding matrix; and precoding the data to be transmitted using the optimized interference alignment-based transmission precoding matrix.