A broadband high resolution direction of arrival estimation algorithm based on conditional wavenumber spectral density

A broadband high resolution direction of arrival(DOA) estimation algorithm named the conditional wavenumber spectral density based(CWSD-based) is proposed in this paper aimed at the problem of large error and high complexity of wideband high resolution DOA.The super-resolution DOA estimation,minimal main-lobe width,ultra-low side-lobe and high precision target resolution performance can be obtained after transforming the array signals to f-k space and using the characteristic of wideband signal power distributed as a line on the conditional wavenumber spectral density.Moreover,there are no DOA pre-estimates of the incident signals and the number of sources to be required in this algorithm.Computer simulations indicate that the theoretical resolution of the algorithm is inversely proportional to the highest processing frequency,the estimated mean square error is about 0.1°,and also is robust to array shape distortion and has high computing efficiency.Experimental data on the sea indicates that the proposed algorithm,whose performance is superior to CBF and MVDR in the aspects of resolution,weak target detection,non-target direction noise suppression and robustness et al.,can achieve ultra-low sidelobe high resolution DOA in the actual ocean.