US 12,340,786 B2
Adaptive noise-canceling with dynamic filter selection based on multiple noise sensor signal phase differences
John Bryan-Merrett, Edinburgh (GB); Mert Salahi, Phoenix, AZ (US); Wilbur Lawrence, Tempe, AZ (US); Samuel P. Ebenezer, Gilbert, AZ (US); and Rachid Kerkoud, Gilbert, AZ (US)
Assigned to CIRRUS LOGIC, INC., Austin, TX (US)
Filed by CIRRUS LOGIC INTERNATIONAL SEMICONDUCTOR LTD., Edinburgh (GB)
Filed on Jul. 27, 2022, as Appl. No. 17/875,364.
Prior Publication US 2024/0038211 A1, Feb. 1, 2024
Int. Cl. G10K 11/178 (2006.01)
CPC G10K 11/17885 (2018.01) [G10K 11/17853 (2018.01); G10K 11/17881 (2018.01)] 32 Claims
OG exemplary drawing
 
17. A method of canceling effects of ambient noise, the method comprising:
sensing the ambient noise with a first acoustic sensor of an adaptive noise-canceling system at a first location to generate a first noise reference signal;
sensing the ambient noise with a second acoustic sensor of the adaptive noise-canceling system at a second location to generate a second noise reference signal;
generating an anti-noise signal with a filter having a selectable response to reduce the presence of the ambient noise, wherein the filter has a response selected by a set of coefficients selected from a collection of coefficient sets;
providing the anti-noise signal to an output electroacoustic transducer;
analyzing the first noise measurement signal and the second noise measurement signal to obtain a phase difference between the first noise measurement signal and the second noise measurement signal;
adjusting an adjustable gain stage coupled in functional series with the filter in response to the phase difference obtained by the analyzing, to obtain an operational gain state of a combination of the adjustable gain stage and the filter;
responsive to the operational gain state being achieved, controlling a response of the filter by selecting the set of coefficients for multiple on-ear conditions of operation, from the collection of coefficient sets according to the phase difference obtained by the analyzing; and
subsequent to selecting the set of coefficients, monitoring the phase difference and dynamically updating the selection of the set of coefficients to maintain the phase difference within a predetermined bound.