Research On The Direction Of Arrival Estimation Algorithms Of Smart Antenna

The smart antenna is one of the key technology in the third generation system. And it has been the present focuses in signal processing field. The smart antenna, which is adapted in the wireless mobile communication systems, in fact, forms an antenna with a high gain. Thus communication in all directions can be proceeded, then base station antenna coverage, system capacity and service quality are improved, also inter-symbol interferes and multi- access interfere are reduced. The space division multiple access (SDMA) is introduced, and users can be distinct from each other through their special location. So the DOA of users plays a very important role in smart antenna systems.The author does some research work on several methods of estimating the number of signal source, and several DOA estimating algorithms. Then the performance of these is compared. An improved MUSIC algorithm based on DCT is presented in this paper. It can estimate the number of signal source and the DOA of the space source effectually without calculating eigenvalues. So the improved algorithm can be faster and easier. The simulation results show the validity of this algorithm.