Study and Simulation of DS-CDMA over Communication Channels

Performance of synchronous DS-CDMA systems over multipath fading channel and AWGN Channel is evaluated. The synchronous DS-CDMA system is well known for eliminating the effects of multiple access interference which limits the capacity and degrades the BER performance of the system. This paper investigated the bit error rate (BER) performance of a synchronous DS-CDMA system over AWGN and Rayleigh channel, which is affected by the different number of users, as well as different types spreading codes. The promising simulation results explore the comparative study of different DS-CDMA system parameter and showed the possibility of applying this system to the wideband channel. In this paper, Rayleigh channel and AWGN Channel are introduced and investigated the bit error rate (BER) performance of a synchronous DS-CDMA system over these channels. In the DS-CDMA system, the narrowband message signal is multiplied by a large bandwidth signal, which is called the spreading of a signal. The spreading signal is generated by convolving a GOLD sequence code with a chip waveform whose duration is much smaller than the symbol duration.