DS-CDMA performance of random orthogonal codes over Nakagami multipath fading channels

The performance of direct-sequence code division multiple-access communication over Nakagami multipath fading channel is examined. Systems employing M-ary random orthogonal signature sequence (or code) modulation and coherent demodulation are investigated. The channel itself is modeled as an independent finite length tapped delay line, and multipath diversity reception is discussed. An approximation to the bit error probability is given by using a Gaussian approximation for the multiple-access interference. Results show that path diversity combining reception can improve the BER performance greatly. Moreover, the analysis shows that the Nakagami-m distribution makes the analysis simpler than the Rician distribution, and models the channel properly.