Linear Multiuser Detection for Synchronous DS-CDMA Systems
نویسنده
چکیده
Direct sequence code division multiple access (DSCDMA) is a popular wireless technology. This system suffers from Multiple Access Interference (MAI) caused by Direct Sequence users and Near –far effect. Multi-User Detection schemes are used to detect the users’ data in presence of MAI and Nearfar problem. In this dissertation, we present comparative study between linear multiuser detectors and conventional single user matched filter in DS-CDMA system. Analysis and simulations are conducted in synchronous AWGN channel, and Gold sequence and Kasami sequence are used as the spreading codes. Simulation results depict the performance of three detectors, conventional detector, Decorrelating detector and MMSE (Minimum Mean Square Error) detector. It shows that the performance of these detectors depends on the length of PN code used and Number of users. Linear multiuser detectors perform better than the conventional matched filter in terms of BER performance. All the simulations have been performed on MATLAB 7.0.
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