System and method for providing a quiet zone
View Patent ↗A system and method for quieting unwanted sound. As a non-limiting example, various aspects of this disclosure provide a system and method, for example implemented in a premises-based or home audio system, for quieting unwanted sound at a particular location.
1. An audio system comprising:
at least one module operable to, at least:
characterize, utilizing at least a first microphone positioned at a location, a relationship between a sound signal used to cause a loudspeaker to output an output sound and the output sound received at the location;
identify, utilizing at least a second microphone and not the first microphone, an unwanted sound at the location;
determine, based at least in part on the determined characterization, a cancellation signal that, when used to cause the loudspeaker to output a counteracting sound, will quiet the unwanted sound at the location; and
generate the cancellation signal to cause the loudspeaker to output the counteracting sound.
2. The audio system of claim 1 , wherein the at least one module is operable to characterize the relationship by, at least in part, operating to determine a transfer function.
3. The audio system of claim 1 , wherein the at least one module is operable to characterize the relationship by, at least in part, operating to:
generate a test stimulus signal to cause the loudspeaker to output a test stimulus;
receive the test stimulus at the location; and
analyze the test stimulus signal and the received test stimulus to determine a functional relationship between the test stimulus signal and the received test stimulus.
4. The audio system of claim 3 , wherein the test stimulus signal comprises a pseudo-random noise signal comprising a pink noise signal.
5. The audio system of claim 3 , wherein the test stimulus signal comprises a swept frequency signal comprising frequencies in a range up to at least twice a quieting passband of the audio system.
6. The audio system of claim 1 , wherein the at least one module is operable to determine the cancellation signal by, at least in part, operating to determine the cancellation signal based, at least in part, on the identified unwanted sound and the characterized relationship.
7. The audio system of claim 6 , wherein the at least one module is operable to determine the cancellation signal by, at least in part, operating to:
determine an inverse of an unwanted sound signal that represents the unwanted sound;
determine the cancellation signal based, at least in part, on the determined inverse.
8. The audio system of claim 1 , wherein the at least one module is operable to determine the cancellation signal by, at least in part, operating to, independent of user input, set a magnitude of the cancellation signal to a level below that determined for ideal cancellation.
9. An audio system comprising:
at least one module operable to, at least:
identify a location;
identify an unwanted sound at the location;
identify, based at least in part on the identified location, a loudspeaker to utilize to quiet the unwanted sound;
determine a counteracting sound that, when output by the loudspeaker, will quiet the unwanted sound at the location; and
output the counteracting sound at the loudspeaker.
10. The audio system of claim 9 , wherein the at least one module is operable to identify the location by, at least in part, operating to receive an input from a user that is unrelated to audio presentation.
11. The audio system of claim 9 , wherein the at least one module is operable to identify the location based, at least in part, on performing sound-based triangulation on a sound made by the user.
12. The audio system of claim 9 , wherein the at least one module is operable to identify the location based, at least in part, on a wireless signal received from a personal electronic device that is independent of the audio system.
13. The audio system of claim 9 , wherein the at least one module is operable to identify the unwanted sound at the location by, at least in part, operating to receive the unwanted sound using at least one sound sensor positioned at the location.
14. The audio system of claim 13 , wherein the at least one module is operable to determine a direction of the unwanted sound, and to determine the counteracting sound based at least in part on the determined direction.
15. The audio system of claim 9 , wherein the at least one module is operable to identify the unwanted sound at the location by, at least in part, operating to receive the unwanted sound using at least one sound sensor positioned at a distance away from the location at least one fourth of a wavelength of a lower bound of a frequency band of sound to be counteracted.
16. The audio system of claim 15 , wherein the at least one module is operable to determine a direction of the unwanted sound, and to determine a counteracting sound based at least in part on the determined direction.
17. The audio system of claim 16 , wherein:
the at least one module is operable to identify the unwanted sound at the location by, at least in part, operating to receive the unwanted sound using at least a first sound sensor positioned away from the location and a second sound sensor positioned away from the location, wherein the first sound sensor and the second sound sensor are positioned at a distance away from the location at least one fourth of a wavelength of a lower bound of a frequency band of sound to be canceled; and
the at least one module is operable to determine the direction of the unwanted sound by, at least in part, operating to determine the direction based at least in part on the unwanted sound received at each of the first and second sound sensors.
18. An audio system comprising:
at least one module operable to, at least:
identify an unwanted sound to counteract;
analyze the identified unwanted sound;
select, based at least in part on the analysis of the identified unwanted sound and independent of user input, between a plurality of different types of countermeasure strategies for counteracting the unwanted sound; and
implement the selected strategy.
19. The audio system of claim 18 , wherein the plurality of different types of countermeasure strategies comprises:
a first countermeasure strategy comprising performing sound cancellation; and
a second countermeasure strategy comprising performing sound masking with a noise signal.
20. The audio system of claim 18 , wherein the plurality of different types of countermeasure strategies comprises:
a first countermeasure strategy comprising performing sound cancellation;
a second countermeasure strategy comprising performing sound masking; and
a third countermeasure strategy comprising performing sound cancellation and sound masking on a same sound to be counteracted.
21. The audio system of claim 20 , wherein the third countermeasure strategy comprises simultaneously performing sound masking and sound cancellation on different respective portions of the same sound to be counteracted.
22. The audio system of claim 20 , wherein the third countermeasure strategy comprises performing sound masking on a first frequency range of the same sound to be counteracted and performing sound cancellation on a second frequency range, different from the first frequency range, of the same sound to be counteracted.