Interleaver design for turbo codes based on divisibility

Interleaver design is important in turbo codes, especially for short turbo codes. Weight-2 input sequences to the interleaver are often used to search for “good” interleavers. We use D-transform to represent the information sequence and parity sequences of a turbo code and introduce an interleaver design principle based on divisibility of information polynomials. Simulation results are obtained for turbo codes using our interleavers, showing a magnitude of improvement in bit error rate (BER) compared to turbo codes using block interleavers and pseudo-random interleavers