Patent ID: 9549245
Date: 2017-01-17
CPC Classifications: G10L,H04R

Claim:
1. A device, comprising: at least three microphone elements; at least one additional microphone element; at least one loudspeaker; at least one housing, wherein the at least one housing is configured to support the at least three microphone elements and the at least one additional microphone element in a first orientation and the at least one loudspeaker in a second orientation; and the at least three microphones are substantially equispaced in a horizontal plane around a circle with a predetermined diameter approximately equal to the wavelength of a predetermined highest frequency of operation of the device and the at least one additional microphone element is positioned at the approximate center of the circle; the at least three microphone elements having substantially equal gain and substantially equal phase and the at least one additional microphone element having a gain substantially equal to the sum of the gains of the at least three microphone elements and a phase shift of about 180 degrees relative to the phase of the at least three microphone elements such that when the signals from the array of microphones are appropriately phased, weighted and summed, the resultant signal in a three-dimensional space is substantially zero in the vertical direction and substantially additive in the horizontal plane direction to achieve a substantial null response in positions having a substantially equal sound path from the at least three microphone elements over a desired audible range of frequencies; and the device is able to provide a response to sounds over a range of second oriented elevations away from the first orientation containing the at least three microphone elements.