Comparison of Error Probability Analyses for Asynchronous DS-CDMA Satellite Communication Systems

There is interest in spread spectrum technology in satellite communications due to its high security and multiple access capabilities. Analyzing the end-to-end communication performance using error probability is critical to optimize the spread spectrum system parameters during the design phase. However, the exact evaluation of error probability is considered a formidable task. In the past, several approximation methods for evaluating the error probability of asynchronous direct sequence CDMA (DS-CDMA) systems were developed, which include Standard Gaussian Approximation (SGA), Simplified Improved Gaussian Approximation (SIGA), Multiple Exponential Moment (MEM), and the characteristic function approach. In this paper, we compare the accuracy of these methods by developing a computer program to simulate the asynchronous DS-CDMA communication systems. Furthermore, we extend SIGA, MEM, and the characteristic function methods to the bandwidth limited chip waveform in the time domain.