Interpolation array technique for direction finding via Taylor series fitting

Interpolation array approach based on Taylor series fitting for arbitrary geometry array is developed in this paper. As the steering vector is a function of direction-of-arrival (DOA), Taylor series fitting for the steering vector is conducted within an angle range, and the steering matrix is decomposed into a coefficient matrix multiplying by a Vandermonde structure vector bearing the DOA information. Moreover, the coefficient matrix is calculated by the least squares method. Results show that the proposed approach has a better DOA estimation performance over the traditional interpolation array technique under uncorrelated and correlated signal conditions.