The Research Of Smart Antenna Beamforming Based On OFDM System

As the use of the Chinese third-generation mobile communications technology standard - TD-SCDMA, smart antenna technology is one of the most active researching fields in the mobile communications systems. Smart Antenna technology has many advantages, such as the characteristic of the SDMA, restraining the same frequency interferences and so on. Facing the issues of the decreasing of the frequency resources and the deteriorated space electromagnetic environment, smart antenna has a good using prospect. Personal mobile communications provides private, independent, convenient communication modes for users which results in the explosive growth of the amount of personal mobile communications users and business flow. To meet the needs of users, increasing the system capacity and the high-speed data transmission and restraining the interferences become the main features of the next generation mobile communication systems.Because OFDM technology has excellent performance in these areas , it become one of the most popular hotspots of the next generation mobile communication systems. The combine of the smart antenna and OFDM technology will make the next generation communication systems have a qualitative leap.In the OFDM system with smart antennas, the beamforming technology is one of the key technologies. In this paper the academic background and the status of the OFDM system with smart antennas are introduced. The OFDM system with smart antennas are analyzed to study the corresponding mathematical model.This paper focuses on the beam-forming algorithms of the OFDM system with smart antennas. The main applications of the classification are analyzed and simulated. And its error rate performance is compared and analyzed. On this basis, this paper presents a beam forming interpolation algorithm, which uses the characteristics of regularity changes in every sub-carriers DOA. a linear interpolation method is used to make every sub-carriers beam referencing the pilot beams.Theoretical analysis and computer simulation results show that the algorithm has a better performance than the others which reduce the complexity of the algorithm.