Performance analysis of DS-CDMA wireless communication system with and without diversity

In this paper, performance of a novel analytic model of direct sequence code division multiple accesses (DS-CDMA) using diversity with maximal ratio combining (MRC) scheme is observed under the influence of multipath Rayleigh fading and multi-access interference (MAI) varying different system parameters and properties of PN sequences. The analysis presents a mathematical expression for bit error rate (BER) of the novel DS-CDMA model using diversity with MRC when signal to interference plus noise ratio (SINR) per bit follows a chi-square distribution. Performance results are evaluated in terms of average bit error rate (BER) at the output of MRC receiver by averaging the conditional BER over the probability density function (pdf) of signal to interference plus noise ratio (SINR). In addition to that the receiver sensitivity of the model is observed for different transmit and receive diversity in a proposed multiple input multiple output (MIMO) system model varying Rayleigh fading co-efficient. Variants of simulation result at various cases are also analyzed.