Researching On The Smart Antenna Technology Of The Wireless Mobile Communication

In these years, with the fast increase of the mobile users and the appearance of new type of wireless services, the wireless services become lager and lager. This results in too much serious Co-Channel Interruption and the Multiple Address Interruption. The band of the transported signals and the signal rate become restricted. At the same time, the transport environment of the wireless signals is complicated and uncertain. So the transported signals are declined and wear down. All this has strong bad effect on the capacity and performance of wireless communication system. The smart antenna technology is an effective solution to take good use of the frequency sources and to promote the capacity and the service quality of the communication system. As known to all, TD-SCDMA is one of the three world 3ird mobile communication standers. It is put forward by Datang Telecom Technology and Industry Group of China. The Smart Antenna technology is one of the key technologies of the TD-SCDMA. It can largely improve the performance of the wireless communication system.The Smart Antenna technology is originally used in military phase-control radar. It's formally called adaptive antenna array. The application research of the Smart Antenna technology in mobile communication filed is from 1990. With the development of the Digital Signal Processing technology and with the rise of the third generation mobile communication and broad-band CDMA, the Smart Antenna technology become a hot research point. The Smart Antenna technology introduce the forth concept of multiple access method SDMA (Space Division Multiple Access).All of the research work of this paper is based on the MATLAB software environment. In this paper, we make an introduction on the appearance background of the Smart Antenna technology and its relative theory and concept. After that, we do some research work on the estimation arithmetic of the signal DOA(Direction Of Arrival) using Smart Antenna Array. The research work is based on the ULA(uniform linear array) antenna. The advanced research work of this paper is: we realize two kinds of DOA estimation arithmetic on the MATLAB software environment. One arithmetic is traditional arithmetic, which include Time-delay method and Capon method. The other one is MUSIC(Multiple Signal Classification) arithmetic. Then we qualitatively compare the performance of these arithmetic with each other. On this basis, we investigate primarily the effects of the Gauss Random Noise caused by antenna array on the MUSIC arithmetic. And we find out the exiting problem. Through simulation of M-file on MATLAB, we innovatively bring forward a effective solution. With the adoption of this elicited solution, the effects of the Gauss Random Noise on the MUSIC arithmetic, which is use to estimate the user signal's DOA, is decreased in largely degree. Thus the DOA estimation performance of the MUSIC arithmetic under the background of Gauss Random Noise is improved.