Searching for quasi-optimal subfamilies of m-sequences for CDMA systems

Abstract

This paper studies several algorithms for constructing quasi-optimal m-sequence subfamilies in terms of minimized BER under co-channel interference. The results show that the performance of resultant sub-families is sensitive to the sub-family sizes and the algorithms employed. A new criterion based on combinational (even plus odd) maximum cross-correlation for the code selection is introduced, based on which both highest-peak-deleting and most-peak-deleting algorithms are effective to construct the quasi-optimal subfamilies.