Abstract:Based on analysis of the principle of Alamouti coding and decoding, a new decoding scheme, based on the symmetry of constellation, is proposed. The new scheme can reduce the calculated amount of calculation of the Alamouti decoding(Maximum Likelihood(ML)decoding). The Matlab software simulation results show that the new scheme can achieve the same BER performance as the old ML decoding scheme. And the new decoding scheme is better in terms of error performance than the old ML decoding scheme at high SNR.