Differential Space-Time Block Code Modulation for DS-CDMA Systems
نویسندگان
چکیده
A differential space-time block code (DSTBC) modulation scheme is used to improve the performance of DS-CDMA systems in fast time-dispersive fading channels. The resulting scheme is referred to as the differential space-time block code modulation for DS-CDMA (DSTBC-CDMA) systems. The new modulation and demodulation schemes are especially studied for the down-link transmission of DS-CDMA systems. We present three demodulation schemes, referred to as the differential space-time block code Rake (D-Rake) receiver, differential space-time block code deterministic (D-Det) receiver, and differential space-time block code deterministic de-prefix (D-Det-DP) receiver, respectively. The D-Det receiver exploits the known information of the spreading sequences and their delayed paths deterministically besides the Rake type combination; consequently, it can outperform the D-Rake receiver, which employs the Rake type combination only. The D-Det-DP receiver avoids the effect of intersymbol interference and hence can offer better performance than the D-Det receiver.
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عنوان ژورنال:
- EURASIP J. Adv. Sig. Proc.
دوره 2002 شماره
صفحات -
تاریخ انتشار 2002