Sub-Nyquist spatial sampling using arrays of directional microphones

Microphone arrays are commonly used for spatial filtering or beamforming. A variety of beamforming techniques offering high spatial resolution have been developed and are described in the literature. However, improved resolution may require an increase in the number of sensors and channels, resulting in complicated and expensive systems. In the current paper the use of arrays composed of directional sensors is proposed and the consequent benefit in terms of a reduction in the number of sensors is analyzed. It is shown that a reduction in the number of sensors can be achieved at the expense of reduced steering capabilities.