A combined determination-estimation method for direction of arrival estimation

A combined determination-estimation method is proposed for direction finding of multiple source locations in this paper. The method is based on the conditional mean multiple signal classification (MUSIC) null-spectrum, and does not require a priori decision on the number of signal sources. It is shown that the shapes of the MUSIC and conditional mean MUSIC null-spectra are not quite different. To see the resolution performance, the probability of resolution (PR) of the MUSIC null-spectrum and that of the conditional mean MUSIC null-spectrum are obtained by computer simulation, from which it is seen that the PRs of these two null-spectra are almost the same. In addition it is found that the information theoretic criterion and Bayesian approach (maximum a posteriori estimation method) for determining the number of signal sources would give the same result.