Direction-of-arrival and diffuseness estimation above spatial aliasing for symmetrical directional microphone arrays

A method for direction-of-arrival (DOA) and diffuseness estimation is presented, which proves to be effective above the spatial aliasing frequency of the microphone array in use. The method assumes symmetrical circular or spherical arrays of directional microphones or microphone mounted on a rigid baffle, and it exploits the inherent directionality of the array at high frequencies. The DOA and diffuseness estimators are shown to exhibit low estimation error above the spatial aliasing limit, compared to commonly used intensity-based estimators. A low-error broadband scheme that combines the intensity-based method and the new one is proposed for the ranges below and above aliasing respectively.