Improvement And Application Of DOA Estimation Algorithm

As a key problem for signal processing, the direction of arrival(DOA) estimation has been playing an increasingly important role in many aspects of social life like sensor networks, public security, environmental monitoring, resource survey, etc. With the widely application of the 3rd generation mobile communication and promoting the fourth generation of mobile communications, new situation brings new problem, such as "multiple access interference". The new environment, therefore, puts forward new requirements on DOA estimation algorithm in order to make the accuracy of algorithm higher, system response faster and more flexible.In this paper, the main work includes:1、Do a study based on MUSIC and MSCS and put forward an improved algorithm. Analysis of characteristics for the MUSIC algorithm and MSCS algorithm is first. When MSCS algorithm searchs near the extreme value, we will use MUSIC algorithm instead of MSCS to guarantee the estimated precision, and retain the MSCS algorithm to reduce the computational complexity at the same time, also improve the algorithm accuracy effectively. The core idea of this method is: in different conditions, we adopt different algorithms(MUSIC or MSCS algorithm) to make best use of the advantages and bypass the disadvantages.2、Study the application of the DOA estimation when array location error exists. The position error of antenna array element will bring inconvenience to other parameter estimation and the subsequent signal processing work. In this paper, we utilize self-calibration thought and a self-calibration weighting function which can be used for the weighed sum of the spectrum values from different directions is constructed.3、A soft frequncy reuse interference coordination scheme combined with DOA beamforming technology will be proposed on the basis of analysis and research for beamforming technology, the simulations verifies that the scheme also improves the performance of system. Numerical result shows that the DOA and beamforming technology can effectively reduce the interference and improve the system performance.