期刊名称：International Journal of Advanced Research In Computer Science and Software Engineering
印刷版ISSN：2277-6451
电子版ISSN：2277-128X
出版年度：2013
卷号：3
期号：9
出版社：S.S. Mishra
摘要：In a Code Division Multiple Access (CDMA) system, many users use simultaneously the entire frequency band to transmit their data and users' data is separated on the basis of their unique spreading code. It is logical that the user spreading code be mutually orthogonal so as to avoid interference among different users. The DS-CDMA system is well known for eliminating the effects of Multiple Access Interference (MAI) which limits the capacity and degrades the BER performance of the system. This paper deals with the bit Error Rate (BER) performance of a DS-CDMA system over AWGN and on different modulation techniques, which is affected by the different number of users. In DS-CDMA systems, overcoming near/far effects and fading is imperative for satisfactory performance. One way to combat the near/far effect is to use stringent power control, as is done in most of the commercial systems. Another approach is Multi-User Detection (MUD). In addition to mitigating the near/far effect, MUD has the more fundamental potential of raising capacity by cancelling MAI. This paper also shows performance evaluation of DS-CDMA with Successive Interference Cancellation (SIC) receiver, which is a sub -optimal method of Multiuser detector (MUD).
