A general construction for orthogonal code set in multicarrier wideband CDMA system

The complete complementary (CC) codes [Suehiro, N et al., 1988] have been used in multicarrier wideband CDMA system [Chen Hsiao-Hua et al., 2001] to improve the performance except that a relatively small number of users can be supported by the codes. In this paper, a general method to construct the orthogonal code set using the sequence with ideal two-level autocorrelation is proposed. The maximal length sequence (M-sequence) is taken as an example to generate the modified M-sequence set. The BER performance of the modified M-sequence is evaluated and compared with the CC code and M-sequence using the simulation. The results indicate that the performance of modified M-sequence is comparable to CC code and much better than M-sequence. The proposed construction method for CC code can remove the drawback of the CC codes, which are limited by relatively small code set