On the capacity of DS-CDMA systems in a Nakagami multipath channel

The coherence reception of direct-sequence/code-division multiple-access (DS/CDMA) signals in a multipath fading channel is considered. The channel model assumes independent paths with Nakagami fading statistics; this model includes the Rayleigh channel as a special case and is a reasonable model for a frequency-selective fading channel. The bit error rate (BER) performance of a RAKE receiver under various multipath fading conditions is derived and evaluated. The results indicate that, when channel coding is used, over 40 users may access the channel (assuming a processing gain of 127) simultaneously under typical fading conditions, and can achieve a BER of 0.001 with an average received signal-to-noise ratio (SNR) per bit of 5 dB.<
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