Spreading Codes Combined Multiple Access and Encryption for ACDMA System

In this paper, the requirements for the spreading codes combined multiple access and encryption for CDMA systems are presented using asynchronous direct sequence CDMA (A-CDMA) systems as a model.In order to investigate the effect of this soft spreading codes on operational performance of A-CDMA system,the probability distribution functions of the even cross-correlation functions of the purely random sequences and Gold codes is compared. Finally, some useful conclusions are obtained.