Improved Log-MAP decoding algorithm for turbo-like codes

In this letter, a new method for decoding turbo-like codes is proposed to simplify the hardware implementation of Log-MAP algorithm. In our method, the multivariable Jacobian logarithm in Log-MAP algorithm is actually concatenated by recursive 1D Jacobian logarithm units. Two new approximations of Log-MAP algorithm based on these 1D units are then presented, which have good approximated accuracy and is simple for hardware implementation. We further suggest a novel decoding scheme that its complexity is near the Max-Log-MAP while the performance is close to the Log-MAP algorithm.