Beamforming is a general signal processing technique used to control the directionality of the reception or transmission of a signal on a transducer array.
Using beamforming you can direct the majority of signal energy you transmit from a group of transducers (like audio speakers or radio antennae) in a chosen angular direction. Or you can calibrate your group of transducers when receiving signals such that you predominently receive from a chosen angular direction. The physics and math are essentially the same for both the transmitting and receiving cases.
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