A fast computation algorithm for DOA evaluation function of MUSIC algorithm in circular array antennas

The MUSIC algorithm is an algorithm that can determine the direction of arr ival (DOA) for multiple radio waves with high precision. In the determinati on of DOA of radiowaves by the MUSIC algorithm, the DOA evaluation function is determined by a large number of the inner product operations between th e steering vector and the eigenvector of the correlation matrix correspondi ng to the receiver noise. A problem from the practical viewpoint is usually how to reduce the computational complexity in those inner product operatio ns. This paper notes that when the antenna is composed only of a circular a rray with equal spacing, the inner product operation depends only on the an gle difference between the element position vector and the Steering vector. Then, a fast operation algorithm is shown, in which the inner product oper ation is reduced to the cyclic convolution operation, and the computational complexity is reduced using the FFT. It is shown that the computational co mplexity is reduced by approximately 31% compared to the conventional metho d, when the array is composed of eight elements. (C) 2001 Scripta Technica