Research On Performance Of Smart Antenna In Rayleigh Fading Channel

Employing antenna array and adaptive array signal processing, the Smart Antenna technique can extend communication resources form the conventional frequency domain, time domain and code domain to the space domain. In mobile communications, Smart Antenna can greatly improve the system reliability and capacity. At the present time, smart antenna technique has become one of the key techniques of the 3rd generation mobile communication.The author's main research work was focused on UCA (Unit Circular Array), analyzed its beam-forming property with the array's radius and the number of antennas. Then several familiar adaptive algorithms were researched and compared. The LS-CMA (Least Square- Constant Modular Algorithm) was selected to process the data received by UCA for its rapid convergence performance in blind adaptive algorithms. At last, the author simulated the performance of UCA in macrocell and microcell assuming the channel being Rayleigh fading. Theoretical analysis and numerical simulation indicated that in macrocell the multipath number and angle spread were both little, so UCA could get great performance improvement than single omni antenna; But in microcell multipath number were commonly much bigger than elements of UCA, and the angle spread was also large, in this environment the performance of UCA was badly depressed, and sometimes it would be worse than diversity antennas. So we could suppose that smart antenna was more suitable to macrocell environment.