SIMPLIFICATION OF LOG-MAP ALGORITHM USED FOR TURBO ITERATIVE DECODING
用于Turbo迭代译码的log-MAP算法的简化

In this paper, logarithm MAP algorithm used for turbo iterative decoding is analyzed and deduced. Based on the characteristic of turbo coding and decoding and the analysis of branch metric in the trellis, methods of simplifying computation of branch metric and extrinsic information are obtained. And then it is done with the computation of ln(ex + ey) in the log-MAP algorithm to further simplify the complexity of log-MAP. Finally, simulation results and analysis are carried out.