Abstract:

To solve the problem of direction of arrival (DOA) estimation, generalized oblique projection operators are constructed to cancel incident signals coming from undesired directions. Since the signals impinging on the array may have different power, one kind of weighting factor is used to balance the height of the spactial spectrum adaptively. Through synchronously suppressing interference and implementing spatial spectrum estimation, a high resolution of the source’s DOA parameters is realized and the phenomenon that the peaks of weak signals are covered by strong ones is avoided. Both the theoretical analyses and the numerical simulation experiments indicate that the proposed approach has good robustness against direction finding of signals, especially the weak sources, with distinct power. The bad influences introduced by the signals’ power can be overcome by the proposed approach, and a high resolution of signals’ DOA parameters can be effectively achieved with different incident angles. What’s more, the standard deviations of the estimated DOAs are asymptotically close to the corresponding Cramer-Rao bound along with the increased snapshots and signal to noise ratio.