Simulation results for a CDMA Interference Cancellation technique in a Rayleigh fading channel
In a Code Division Multiple Access (CDMA) mobile radio communications system, interference from other users is one of the most critical drawbacks, and the Interference Cancellation (IC) technique is a method that, by exploiting orthogonal modulation properties, has been presented to reduce the effects and to increase the overall performance. The paper introduces some features of the CDMA-IC technique for the up-link (from mobile stations to base station) of a mobile radio system and describes a simple algorithm to generate the power list needed for the demodulation of the users' signals according to their received power. The use of non coherent reception has been investigated to avoid any channel estimation.
Performance in terms of Bit Error Ratio (BER.) has been evaluated in a Rayleigh fading channel and the behaviour of the system has been studied also with non perfect power control and chip synchronization.
Simulations have shown that the IC technique allows an improvement in performance with respect to the conventional CDMA and that the method is less sensitive to non perfect power control and chip synchronization.
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