Turbo Code Interleaver Design Based On An Integrated Optimization Considerations

Since the first appearance of Turbo codes and a related structure in 1993, Turbo codes are deemed to be one of the most exciting and potentially important developments in coding theory in many years. Turbo codes also introduce a further dimension to interleaver requirements. Appropriate choice of interleavers is important to take advantage of coding gains that Turbo codes can offer.Main requirements for interleaver design are discussed in the paper. Using a flexible software Turbo codec and simulation environment we established., the performances of various classical interleavers are compared and analyzed. An optimized interleaver design technique based on S-random algorithm is proposed to simultaneous optimization of several requirements for interleaver design - the results obtained show that it is an effective technique. After analyzing the results we obtained, some key requirements and suggestions for simultaneous optimization in interleaver design are given.As a soft-decision algorithm for optimization, Simulated-Annealing algorithm has proved effective in interleaver design. In this paper, we also demonstrate how to use it in simultaneous optimization of several optimization requirements for interleaver design. Some small block size Simulated-Annealing interleavers are designed and BER performances of Turbo codec systems with these interleavers are obtained from simulation.