Quiet zone control system
First Claim
1. A non-transitory computer-readable medium comprising a plurality of instructions executable by a processor to create a quiet zone in a listening area, the non-transitory computer-readable medium comprising:
- instructions to determine a first filter adjustment based on a first error signal indicative of an undesired sound in a first listening region included in the listening area;
instructions to determine a second filter adjustment based on a second error signal indicative of the undesired sound in a second listening region included in the listening area;
instructions to set and apply a first weighing factor to the first filter adjustment, and set and apply a second weighting factor to the second filter adjustment, the first and second weighting factors set to values selected from a plurality of non-zero incremental values; and
instructions to update a set of filter coefficients of an adaptive filter based on the first weighted filter adjustment and the second weighted filter adjustment, the adaptive filter configured to generate an anti-noise signal to destructively interfere with the undesired sound to create the quiet zone.
3 Assignments
0 Petitions
Accused Products
Abstract
An active noise control system generates an anti-noise signal to drive a speaker to produce sound waves to destructively interfere with an undesired sound in a quiet zone. The anti-noise signal is generated with an adaptive filter having filter coefficients. The coefficients of the adaptive filter may be adjusted based on a first filter adjustment from a first listening region, and a second filter adjustment from a second listening region. A first weighting factor may be applied to the first filter adjustment, and a second weighting factor may be applied to the second filter adjustment. The first and second weighting factors may dictate the location and size of the quiet zone as being outside or partially within at least one of the first listening region and the second listening region.
198 Citations
29 Claims
-
1. A non-transitory computer-readable medium comprising a plurality of instructions executable by a processor to create a quiet zone in a listening area, the non-transitory computer-readable medium comprising:
-
instructions to determine a first filter adjustment based on a first error signal indicative of an undesired sound in a first listening region included in the listening area; instructions to determine a second filter adjustment based on a second error signal indicative of the undesired sound in a second listening region included in the listening area; instructions to set and apply a first weighing factor to the first filter adjustment, and set and apply a second weighting factor to the second filter adjustment, the first and second weighting factors set to values selected from a plurality of non-zero incremental values; and instructions to update a set of filter coefficients of an adaptive filter based on the first weighted filter adjustment and the second weighted filter adjustment, the adaptive filter configured to generate an anti-noise signal to destructively interfere with the undesired sound to create the quiet zone. - View Dependent Claims (2, 3, 4, 5, 6)
-
-
7. A non-transitory computer-readable medium comprising a plurality of instructions executable by a processor to create a quiet zone in a listening area, the non-transitory computer-readable medium comprising:
-
instructions to retrieve a first set of weighting factors and a second set of weighting factors, a first location and size of a first quiet zone based on the first set of weighting factors, and a second location and size of a second quiet zone based on the second set of weighting factors, each of the first and second sets of weighting factors being different non-zero values from within range of non-zero values; instructions to calculate a first filter adjustment based on the undesired sound and a first error signal received from a first listening region; instructions to calculate a second filter adjustment based on the undesired sound and a second error signal received from a second listening region; instructions to apply the first set of weighting factors to the first filter adjustment and the second filter adjustment to update a first adaptive filter, the first adaptive filter configured to generate a first anti-noise signal to destructively interfere with the undesired sound to produce the first quiet zone; and instructions to apply the second set of weighting factors to the first filter adjustment and the second filter adjustment to update a second adaptive filter, the second adaptive filter configured to generate a second anti-noise signal to destructively interfere with the undesired sound to produce the second quiet zone. - View Dependent Claims (8, 9, 10, 11, 12, 13, 14)
-
-
15. An active noise control system for creating a quiet zone in a listening area, the active noise control system comprising:
-
a processor; a memory in communication with the processor; where the processor is configured to retrieve a first weighting factor and a second weighting factor from among a plurality of distinct non-zero values, the first weighting factor and the second weighting factor configured to shape an area of the quiet zone within the listening area; the processor further configured to apply the first weighting factor to a first filter adjustment of a first listening region included in the listening area and apply the second weighting factor to a second filter adjustment of a second listening region included in the listening area; the processor further configured to update filter coefficients of an adaptive filter included in the active noise control system based on the weighted first filter adjustment and the weighted second filter adjustment; and the processor further configured to generate an anti-noise signal with the updated set of filter coefficients of the adaptive filter to destructively interfere with an undesired sound and create the quiet zone. - View Dependent Claims (16, 17)
-
-
18. A method of creating a quiet zone with an active noise control system in a listening area, the method comprising:
-
receiving a first error signal indicative of undesired sound in a first listening region and receiving a second error signal indicative of undesired sound in a second listening region; calculating a first filter adjustment based on the first error signal and the undesired sound, and calculating a second filter adjustment based on the second error signal and the undesired sound; selecting each of a first weighting factor and a second weighting factor from a plurality of distinct non-zero values to modify the first filter adjustment and the second filter adjustment, respectively; applying the first weighting to the first filter adjustment of the first listening region included in the listening area and applying the second weighting to the second filter adjustment of the second listening region included in the listening area to establish the quiet zone within the listening area as non-inclusive of both the first listening region and the second listening region; adjusting filter coefficients of an adaptive filter based on the weighted first filter adjustment and the weighted second filter adjustment; and generating an anti-noise signal to substantially cancel the undesired sound and create the quiet zone. - View Dependent Claims (19, 20, 21)
-
-
22. A method of creating a quiet zone with an active noise control system, the method comprising:
-
calculating a first filter adjustment based on a first error signal representative of undesired sound in a first listening zone and calculating a second filter adjustment based on a second error signal representative of undesired sound in a second listening zone; setting each of a first weighting factor and a second weighting factor to respective values selected from a plurality of distinct non-zero values; applying the first weighting factor to the first filter adjustment and the second weighting factor to the second filter adjustment; and adjusting an adaptive filter based on the weighted first filter adjustment and the weighted second filter adjustment to establish a size of the quiet zone to exclude at least a part of the first listening zone and the second listening zone. - View Dependent Claims (23, 24)
-
-
25. A method of creating a quiet zone with an active noise control system, the method comprising:
-
providing a plurality of secondary path transfer functions representative of a plurality respective paths between at least one speaker and at least one error microphone; calculating a first filter adjustment for a first listening region based on at least a first one of the secondary path transfer functions and calculating a second filter adjustment for a second listening region based on at least a second one of the secondary path transfer functions that is different than the first one of the secondary path transfer functions; selecting a first weighting factor to adjust but not eliminate the first filter adjustment and a second weighting factor to adjust but not eliminate the second filter adjustment, the first weighting factor different from the second weighting factor; applying the first weighting factor to the first filter adjustment and the second weighting factor to the second filter adjustment; adjusting an adaptive filter with the weighted first filter adjustment and the weighted second filter adjustment to establish a size of the quiet zone; and generating an anti-noise signal with the adjusted adaptive filter to substantially cancel the undesired sound. - View Dependent Claims (26, 27, 28)
-
-
29. A method of creating a quiet zone with an active noise control system, the method comprising:
-
providing a plurality of secondary path transfer functions representative of a plurality respective paths between at least one speaker and at least one error microphone; receiving a first error signal from a first listening area and receiving a second error signal from a second listening area, the first listening area and the second listening area being subject to an undesired sound; calculating a first filter adjustment of an adaptive filter based on the first error signal and at least one of the secondary path transfer functions and calculating a second filter adjustment of the adaptive filter based on the second error signal at least one of the secondary path transfer functions; applying a first non-zero weighting factor to the first filter adjustment and a second non-zero weighting factor to the second filter adjustment, the first weighting factor different from the second weighting factor; and updating coefficients of the adaptive filter with both the weighted first filter adjustment and the weighted second filter adjustment to produce the quiet zone to exclude at least part of the second listening area.
-
Specification