CPC G10K 11/17879 (2018.01) [G10K 11/17833 (2018.01); H04R 3/00 (2013.01); G10K 2210/1282 (2013.01); H04R 2499/13 (2013.01)] | 16 Claims |
1. A noise-cancellation system, comprising:
a noise-cancellation filter in communication with at least one speaker, the noise-cancellation filter generating a noise-cancellation signal;
an amplifier disposed between the noise-cancellation filter and the at least one speaker, the amplifier applying a first scaling gain to a current sample of the noise-cancellation signal and outputting a scaled noise-cancellation signal to the at least one speaker, the scaled noise-cancellation signal being a linear reduction of the current sample of the noise-cancellation signal when the first scaling gain is less than unity; and
a limiter disposed between the amplifier and the at least one speaker;
wherein the first scaling gain is set to less than unity in response to a signal representative of the noise-cancellation signal exceeding a threshold, wherein, the scaled noise-cancellation signal, when actuated by the at least one speaker, cancels noise within at least one cancellation zone, wherein the signal representative of the noise-cancellation signal is the scaled noise-cancellation signal from a previous sample of the noise-cancellation signal, wherein the threshold is the threshold of the limiter.
|