Patent ID: 11922918
Assignee: FAURECIA CREO AB
Field: Other consumer goods (Other fields)
Classification: CPC G | IPC G

Claim 13:
14. A noise controlling system, comprising:
one reference sensor configured to generate one reference signal representing a primary noise;
one sound source configured to generate one secondary noise in response to a control signal, for cancelling the primary noise; and
one error sensor configured to generate one error signal representing a superposition of the primary noise and the one secondary noise at a position;
wherein the system further comprises:
an additional reference sensor configured to generate an additional reference signal;
and/or an additional sound source configured to generate an additional secondary noise in response to an additional control signal;
and/or an additional error sensor configured to generate an additional error signal; and
a control circuit configured to generate the control signal(s) for generating the secondary noise(s), by executing an adaptive subband filtering algorithm based on the reference signal(s) and the error signal(s);

wherein the control circuit is further configured to:
decompose the reference signal(s) and the error signal(s) into subband reference signal(s) and subband error signal(s), respectively, for each subband of a plurality of subbands;
provide subband adaptive filters for each subband for processing the subband reference signal(s) and the subband error signal(s);
update only a subset of the subband adaptive filters for at least one subband of the plurality of subbands, based on only a subset of the subband reference signal(s) of the at least one subband and only a subset of the subband error signal(s) of the at least one subband, wherein at least one of the three said subsets is a proper subset;
update at least one fullband adaptive filter based on the updated subband adaptive filter(s); and
generate the control signal(s) by filtering the reference signal(s) by the updated at least one fullband adaptive filter.