Minimally sensitive digital filters for array data processing

Digital filters are derived for the off-line processing of the recordings of an array of sensors in order to extract a desired signal corrupted by coherent interference. If the values of the amplitudes and delay times of the coherent interfering signal at the sensors are known exactly, the derived array filters achieve an all pass condition for the desired signal and minimum array response to the coherent interference. More importantly, if only estimates of the amplitudes and delay times are known, the derived array filters are minimally sensitive to the perturbations in these parameters. An illustrative example demonstrates the superiority of the derived array filters-under parameter perturbations-when compared to similar array filters.