Mitigation of Close-Bearing Interference in Horizontal Arrays Using Frequency–Wavenumber Deconvolution

Close-bearing sources produce overlapping spatial responses in finite-aperture horizontal arrays, affecting amplitude-envelope estimation. This letter evaluates frequency–wavenumber Richardson–Lucy deconvolution using paired simulations of incoherent narrowband sources. At a bearing separation of 0.6°, the median normalized envelope deviation is reduced by 22.9% relative to conventional beamforming. Improvements occur at the tested separations from 0.2° to 0.8°, but reverse at 1.0° and above. With a 6 dB source-level difference, both the improvement at 0.6° and the degradation at 1.0° are more pronounced for the weaker source. Comparisons with the prescribed source envelopes confirm the same trends in normalized envelope error.