DOA estimation with fourth order propagator

In this paper, we derive a new propagator operator for estimating the Angles Of Arrival (AOA) of farfield narrowband electromagnetic waves impinging on antenna array when its number of sensors is larger than the number of radiating sources. The fourth order partition, of the array steering matrix, is presented to estimate the noise subspace using non diagonal partial cross correlation sub-matrices without the eigendecomposition while using all the sensors of the antenna. The Simulation results in presence of an additive white noise and real symmetric Toeplitz noise proved the efficiency of the proposed method comparatively to the ESPRIT estimator.