Noise cancellation enabled audio device and noise cancellation system
A noise cancellation enabled audio device, in particular a headphone, comprises a speaker which is arranged within the audio device and which has a preferential side for sound emission. The audio device further comprises a first cavity enclosing a first volume of air, where the first cavity is arranged at the preferential side for sound emission of the speaker, and an error microphone which is arranged within a second cavity within the audio device. The first cavity comprises a first opening to the outside of the audio device and the second cavity comprises a second opening to the outside of the audio device. The first and the second opening are both arranged on a side of the audio device which is arranged to face an ear canal of a user. Furthermore, a noise cancellation system is provided.
1. A noise cancellation enabled audio device, the audio device comprising
a speaker which is arranged within the audio device and which has a preferential side for sound emission,
a first cavity enclosing a first volume of air, where the first cavity is arranged at the preferential side for sound emission of the speaker, and
an error microphone which is arranged within a second cavity within the audio device, wherein:
the first cavity comprises a first opening to an outside of the audio device and the second cavity comprises a second opening to the outside of the audio device,
the first and the second opening are both arranged on a side of the audio device which is arranged to face an ear canal of a user,
the error microphone is directly coupled to the volume of air within the ear canal, and
the second cavity is separated from the first cavity by a separating wall.
2. The noise cancellation enabled audio device according to claim 1 , wherein once the audio device is placed in the ear canal of a user a channel remains in places between the audio device and the ear canal of the user.
3. The noise cancellation enabled audio device according to claim 2 , wherein the channel is permeable for air and sound waves.
4. The noise cancellation enabled audio device according to claim 1 , wherein the second opening is the only opening in the second cavity.
5. The noise cancellation enabled audio device according to claim 1 , wherein the second cavity encloses a second volume of air which is directly coupled to a volume of air within the ear canal of a user in case that the audio device is placed within the ear canal of the user.
6. The noise cancellation enabled audio device according to claim 1 , wherein a mesh is arranged over the first opening.
7. The noise cancellation enabled audio device according to claim 1 , wherein a mesh is arranged over the second opening.
8. The noise cancellation enabled audio device according to claim 1 , wherein the error microphone is arranged to primarily record sound within the ear canal of a user.
9. The noise cancellation enabled audio device according to claim 1 , wherein the error microphone acts as a feedback microphone.
10. The noise cancellation enabled audio device according to claim 1 , wherein the error microphone is arranged within the second opening at least partially such that the error microphone terminates flush with a housing of the audio device.
11. The noise cancellation enabled audio device according to claim 1 , wherein the first and the second opening are arranged adjacent to each other.
12. The noise cancellation enabled audio device according to claim 1 , wherein the first opening and the second opening are parallel to one another.
13. The noise cancellation enabled audio device according to claim 1 , wherein the first opening and the second opening are not parallel to one another.
14. The noise cancellation enabled audio device according to claim 1 , wherein the error microphone is arranged at a shorter distance to the side of the audio device than the speaker.
15. The noise cancellation enabled audio device according to claim 1 , wherein a feed-forward microphone is arranged at a side of the audio device which faces away from the side where the error microphone is arranged.
16. The noise cancellation enabled audio device according to claim 15 , wherein the feed-forward microphone is arranged to record sound from the environment of the audio device and to provide a noise signal related to the recorded sound.
17. The noise cancellation enabled audio device according to claim 1 , wherein the noise cancellation enabled audio device is a headphone.
18. The noise cancellation enabled audio device according to claim 1 , wherein the second cavity is delimited by the separating wall, a housing of the audio device, and the second opening.
19. The noise cancellation enabled audio device according to claim 1 , wherein the error microphone is directly coupled to the second cavity.
20. The noise cancellation system comprising the audio device according to claim 15 , wherein the noise cancellation system comprises a filter which is coupled between the feed-forward microphone and the speaker.
21. The noise cancellation system according to claim 20 , wherein the filter is arranged to provide a noise cancellation signal based on the noise signal to the speaker.
22. The noise cancellation system according to claim 21 , wherein the noise cancellation signal is further based on an error signal provided by the error microphone where the error signal is related to the sound recorded by the error microphone.