A fast DOA estimation method based on cosine characteristic

The complicated operation of finding direction must be reduced to satisfy the real time finding direction processing. Now, there are many finding direction algorithms. The MUSIC like algorithm based on the uniform circle array is applied to the practice system. Because this algorithm has width frequency ranges. Both of the elevation and azimuth can be estimated. This algorithm also can provide accurate estimation efficiently. The performance of this algorithm is solidity and robust. The direction of arrival estimation has the same capability from the different azimuth. Analysis is done on the steering vector of the uniform circular array aiming at the geometry of the uniform circular array. Then, a fast DOA estimation method based on cosine characteristic is put forward. First, this method constructs the statistical variable. This variable has relation with elevation only, which has no relation with azimuth. So the estimation of elevation angle can be get by cosine characteristic. Then, the two dimensional search is replaced by the one dimensional search by the estimation of elevation angle. The complicated operation of finding direction is reduced consumedly. This algorithm can provide accurate estimation efficiently. This algorithm is suited to applied situation of the many array number. Compared with the existing 2-D direction of arrival estimation algorithm, the superiority of this algorithm is evident in the computational load. At the same time, there are two signals in the practice narrowband system. The two signals interacts each other. This paper distills the anticipant signal by digital filter to reduce the effect on small signal. The simulation results validate the efficiency of the method. Performance of this algorithm is robust than the other algorithms. Compared with the existing finding direction algorithm, the superiority of this algorithm is evident in the computational load.