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Regularized Optimum Beamforming for Downlink CDMA Systems

By Najib A. Odhah, Kamal Awadalla, Moawad Ibrahim Dessouky, and Fathi Abd El-Samie
Progress In Electromagnetics Research C, Vol. 5, 195-207, 2008


In this paper, we propose an efficient technique to mitigate the effects of both multiple access interference (MAI) and intersymbol interference (ISI) in downlink wireless CDMA systems. A hybrid scheme comprising beamforming at the base station and a regularized zero forcing equalizer at the mobile unit is suggested and studied. The proposed scheme uses the beamforming to reduce the effect of the MAI. Then, the regularized zero forcing equalizer is used to reduce the effect of ISI and provide a better estimate of the data. The performance of the proposed scheme is studied and compared with traditional schemes. Our simulation results show a noticeable performance improvement by using the proposed scheme with low complexity at the mobile unit.


Najib A. Odhah, Kamal Awadalla, Moawad Ibrahim Dessouky, and Fathi Abd El-Samie, "Regularized Optimum Beamforming for Downlink CDMA Systems," Progress In Electromagnetics Research C, Vol. 5, 195-207, 2008.


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