Title :
Performance of iterative DS-CDMA m-ary demodulation in the presence of synchronization errors
Author :
Xiao, Pei ; StröM, Erik
Author_Institution :
Dept. of Signals & Syst., Chalmers Univ. of Technol., Goteborg, Sweden
Abstract :
The robustness of different interactive schemes for demodulating M-ary orthogonal signaling formats in asynchronous DS-CDMA systems to the synchronization errors is addressed. The system under study resembles the uplink of an IS-95 system. The channel is assumed to be a time-varying flat Rayleigh-fading channel. Our simulation results show that the 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
Keywords :
Rayleigh channels; cellular radio; code division multiple access; demodulation; filtering theory; interference suppression; matched filters; multiuser channels; parameter estimation; radio links; radiofrequency interference; signal detection; spread spectrum communication; synchronisation; time-varying channels; IS-95 system; M-ary orthogonal signaling formats; asynchronous DS-CDMA systems; channel estimation; coherent detection algorithms; demodulation; flat Rayleigh-fading channel; iterative DS-CDMA M-ary demodulation; iterative interference suppression; matched filter; multiuser detectors; noncoherent detection algorithms; parallel interference cancellation; performance degradation; simulation results; synchronization errors; time-varying channel; uplink; Channel estimation; Degradation; Demodulation; Detection algorithms; Detectors; Discrete event simulation; Matched filters; Multiaccess communication; Rayleigh channels; Robustness;
Conference_Titel :
Vehicular Technology Conference, 2001. VTC 2001 Spring. IEEE VTS 53rd
Conference_Location :
Rhodes
Print_ISBN :
0-7803-6728-6
DOI :
10.1109/VETECS.2001.944985
