الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
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Abstract
In this thesis we discuss the troublesome existence of multipath fading in communication channels. In those channels (such as ionospheric and tropospheric channels), the signal proceeds to the receiver along not one, but many paths. The receiver performance is analyzed usmg eigen analysis via the Karhunen-Loeve transformation (KLT) in the cases of single antenna and of uncorrelated space diversity reception. This discussion is made by taking into consideration the effect of non zero sidelobe levels of spread spectrum codes taken as shaping pulses. This analysis is extended to the case of correlated antennas diversity reception which results from closely placed antennas. In this extension a modified KLT receiver is proposed to combat the effect of this correlation. The proposed receiver uses a decorrelation filter based on adaptive cascaded Gram Schmidt processor.”The effect of reducing the number of eigen correlators at the receiver is also studied for different multipath situations. A complete comparison of the KLT receiver and a RAKE receiver with multipath decorrelation is made for different number of paths, and of symbol shaping Pulses. The performance of the RAKE receiver is slightly better than the KLT receiver because we use a multipath decorrelation filter.
Finally all previous. performance analysis is extended to multi-user detection in synchronous Code Division Multiple Access (CDMA) in Rayleigh fading multipath communication channels. An interference cancellation receiver is suggested to reduce the bad effects of the users’ crosscorrelations and the diversity branches correlation