An Interleaver Estimation Algorithm for Turbo-code Based on Conformity of Parity-Check Equation

The most existing methods for estimation of interleaver are based on hard decision sequences, which has a poor fault tolerance. Moreover, some of them are only effective for specific interleavers. For traditional turbo code of rate 1/3, the estimation algorithm based on the average conformity of parity-check equation recognizes turbo-code interleaver by using soft decision sequences, which can get better anti-noise property. However this method must traverse the former permutation, which greatly increases the calculation of the algorithm. A novel algorithm of the aforementioned method is proposed in this paper. Permutation is recovered by employing the method of column vector comparison, which reduces the computational complexity and it still has an extremely great recognition performance in low signal-to-noise ratio (SNR).