Transmit Diversity versus Beamforming System in Correlated Fading Channel

Abdul W. Umrani, Yong L. Guan, Fahim A. Umrani
DOI: 10.4236/ijcns.2010.38089                

Abstract

The performance analysis, using outage capacity for a forward link cellular communications system is presented. The effects of correlated fading, the distribution of angle of arrivals, and the array configurations are considered. The objective is to examine the effect of angle of arrival (AOA) energy distributions on two systems (transmit diversity and beamforming) with angle spread. We do so by comparing the performance of transmit diversity with a system that uses beamforming to point a relatively narrow beam at the mobile station. Analytical results show that the transmit diversity system using uniform linear arrays (ULA) and uniform circular arrays (UCA) with truncated Laplacian AOA, performs better even at smaller angle spreads as compared to other energy distributions. The ULA geometry is a preferable configuration for transmit diversity system as compared to UCA.

Keywords

Antenna Arrays, Angle Spread, Fading Correlation, Diversity Performance, Fading Channels, Cellular Radio

Conflicts of Interest

The authors declare no conflicts of interest.

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