Study On Smart Antennas At Mobile Terminal For TD-SCDMA Systems

As a key technology of future mobile communication, smart antennas can increase cellular system capacity, extend radio coverage, and improve quality of services. Until now, smart antennas has been mainly studied for base station, little attention has been spend on mobile terminal because of its limit on space, processing power and cost. With the fast development of micro-electronics technology, high speed, low power, low cost processors can be available in near future that make the smart antenna at small mobile terminal possible. So, the study of smart antenna at mobile terminal is significative. This dissertation studied a dual smart antenna at mobile terminal for TD-SCDMA system. The job has been done are mainly presented as follows:Make an analysis to the characteristic of wireless mobile channel. Establish a statistical vector fading channel model applied to smart antenna simulation.Do simulations to several adaptive beamforming algorithms with MATLAB. We get the results that NLMS algorithm is feasible for smart antenna at mobile terminals. Propose a new half blind algorithm which is more robust than NLMS algorithm. Make an analysis to the interferes that mobile terminals may be suffered in TD-SCDMA system. Through MATLAB simulation we got the bit error rate performances of dual smart antenna and single antenna, then the superiority of dual smart antenna was proved. The performance analysis of dual smart antenna under different circumstance was be done. The space-time 2D-RAKE receiver was also been studied, its performance is better than smart antenna with the cost of more complexity.Use FPGA and DSP to implement the NLMS algorithm used by TD-SCDMA mobile terminal. The result shows that the FPGA method can satisfy the real time requirement easily.