1. Field
This disclosure relates to audio signal processing.
2. Background
Beamforming is a signal processing technique originally used in sensor arrays (e.g., microphone arrays) for directional signal transmission or reception. This spatial selectivity is achieved by using fixed or adaptive receive/transmit beampatterns. Examples of fixed beamformers include the delay-and-sum beamformer (DSB) and the superdirective beamformer, each of which is a special case of the minimum variance distortionless response (MVDR) beamformer.
Due to the reciprocity principle of acoustics, microphone beamformer theories that are used to create sound pick-up patterns may be applied to speaker arrays instead to achieve sound projection patterns. For example, beamforming theories may be applied to an array of speakers to steer a sound projection to a desired direction in space.