Investigation On Adaptive Beamforming Algorithms For Smart Antenna System And FPGA Implementation

Smart antenna is the product of the development of array signal processing technology.It can be seen as a group of sensors placed at different locations in space at a certain way.The space communication signals received by the sensor array is processed through proper adaptive signal processing network, and extract the desired signal source and signal required attributes Essentially it is a spatial filter, and it is committed to the development of space resources.Adaptive algorithms for beamforming are used to produce spatial and directional beam in smart antenna. Then the main beam aims at the coming direction of desired user and the side lobe or null points to the coming directionof interference user,which is based on the spatial, information of users, so the signal of desired user will been hanced, the signal of interference user will be restrained,and the anti-noise ability of the system is remarkably developed. Adaptive algorithm forbeamforming obtain the optimal weight vector by iteration, so faster convergence rate and smaller steady-state error are adecision factors.for beamforming performance. Therefore, the paper study the antenna for adaptive beamforming in a deep research. Its includes the fellowing contents:firstly, introducing the principle structure of smart antenna that based on the analysis and comparison of various guidelines and typical beamforming algorithm;Then introduces algorithm based on time reference LMS, RLS and space-based DOA algorithm. And next by simulation of its convergence speed and the effect of the formation of beams were compared.Then for the LMS algorithm is not suitable for high speed real-time signal processing,is proves that the DLMS algorithm is derived.By analyzing and comparing,the simulation results show that DLMS algorithm is sacrifice some of the cost of convergence rate getting high-speed parallel processing capabilities. So using of the adaptive beamforming DLMS system can reach to the desired signal enhancement, for the purpose of nulling interference signals.Finally, A hardware implement scheme of DLMS algorithm based on FPGA is Designed in the article. Using Altera company Stratix series of EPIS10B672C6 chip and various EDA tools, hardware design and the FPGA simulation is finished.