Performance boosting approach of S-Random interleaver for IDMA system using Walsh code

This paper presents S-Random interleaver based Interleave Division Multiple Access (IDMA) scheme. S-Random interleaver provides good spreading parameter which produce less correlated extrinsic values and also lowers down the error floor, hence better the system performance. As interleavers in IDMA used to recognize the different signal from the different users, S-Random interleavers are employed in IDMA for user separation and also provide significant improvement in BER performance as compared to that of conventional random interleaver. In this paper performance analysis of S-Random and random interleaver for iterative IDMA system have been evaluated with BPSK modulation in Rayleigh Fading channel. Further, the system performance can be improved significantly by the inclusion of optimal spread code such as Walsh-Hadamard code. Simulation results are given in terms of spread parameter, BER performance.