Performance of Iterative DS-CDMA M-ary Demodulation in the Presence of Synchronization Errors
نویسندگان
چکیده
The robustness of different interactive schemes for demodulating M-ary orthogonal signaling formats in asynchronous DS-CDMA systems to the synchronization errors is addressed in this paper. The system under study resembles the uplink of an IS-95 system. The channel is assumed to be a time-varing flat Rayleigh-fading channel. Our simulation results show that performance degradation for the considered multi-user detectors increase linearly with synchronization errors and eventually converge to that of conventional matched filter. In order to see the impact of channel estimation on the performance of multi-user detectors, we made some comparisons between non-coherent and coherent variants of the detection algorithms.
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Synchronization algorithms for iterative demodulated M-ary DS-CDMA systems
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