Patent ID: 8611552
Filing Date: 2013-12-17
Classification: A61F,G10K,H04R

Abstract:
1. A method for reducing an acoustic energy level at a listening position, the method comprising: receiving a primary acoustic wave at a first reference position to form a first reference signal; receiving the primary acoustic wave at a second reference position to form a second reference signal; separating each of the first reference signal and the second reference signal into a plurality of sub-band signals in the frequency domain; determining, in the frequency domain, a direction of propagation of the primary acoustic wave for each sub-band of the first reference sub-band signal and each sub-band of the second reference sub-band signal based on the first and second reference sub-band signals; forming, in the frequency domain, a feedforward sub-band signal based on the determined direction of propagation of the primary acoustic wave; and generating a secondary acoustic wave based on the feedforward sub-band signal, the secondary acoustic wave adapted to reduce the acoustic energy level at the listening position.