On a high resolution array processing method non-based on the eigenanalysis approach

A concept for array processing was recently introduced under the name of `propagator´. The properties of this concept have since been proven useful for source bearing estimation problems in difficult situations. The propagator is a linear operator which can easily be extracted from the cross-spectral matrix of the signals received on the array without any eigendecomposition of this matrix. It is shown that the propagator method, used for the multiple source direction of arrivals estimation may have a theoretically asymptotical high resolution power. This is true if the noise correlation matrix is known except for a constant multiple as it is also required for the eigendecomposition-based methods. It is shown that a joint estimation of the propagator, the noise variance, and the number of sources can be performed and that the solution is unique