The effect of the chip rate on the performance of a CDMA system with a selective fading channel

The bit error probability is determined for direct-sequence code-division multiple-access (CDMA) system communications over doubly selective fading channels. The effect of the chip rate on the performance is considered for both a correlation receiver and a rake receiver. Several selective fading channels are employed as examples to illustrate that the choice of the best chip rate depends upon the characteristics of the channel and the number of taps in the rake receiver. The tradeoff between the number of taps and the bit error probability is investigated for different chip rates. Additionally, the effects of Doppler spread on the performance of the system and the choice of chip rate are considered