Study Of Smart Antenna Algorithm And Its Implementation On DSP

Digital signal processing technologies were used to produce spatial and directional beam in smart antennas. Then the main beam aims at the coming direction of reference user and the side lobe points to the coming direction of interference user. The Smart Antenna Systems (SAS) has become one of the key techniques of the Third Generation Mobile Communication Systems (3G) for its advantages on multiple access interference (MAI) suppression by using spatial information. It can be compatible with the present techniques (TDMA, FDMA and CDMA), and can remarkably improve the performance and the capacity of communication systems.In this paper, firstly, the author illustrates the principles of smart antenna and adaptive beamforming, and then introduces some typical adaptive algorithms used in CDMA systems, but they have the disadvantage of high complexity, so they are not fit for practice. Based on these works, the author proposes two novel, low computational load DS-CDMA uplink blind beamforming algorithms, simulates the algorithms and analyses the performance. One of which is based on the maximum signal-to-noise ratio (MSNR) criterion, it can improve the performance of the array system only when the processing gain of the given CDMA system is high enough such that the desired signal can become dominant after dispreading. The other is based on the maximum signal-to-interference- plus-noise ratio (MSINR) criterion, and it has well performance when strong interferers occur. In the last chapter, the author introduces some knowledge of Digital Signal Processor (DSP), and in order to research the real-time performance, the author implements the above algorithms on TMS320C5402 DSP chip, and its processing speed is 100MIPS. It is of great value in engineering application and is a good guide to theory study in the future.