Noise canceling audio headset
AssigneeDevialet
InventorsEmil Garnell, Vu Hoang Co Thuy
Life of this patent
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Abstract
The headset includes an electro-acoustic transducer, at least one noise reduction processing chain including external and internal microphones, a processing filter including mounted in parallel between the external microphone and an adder, at least one elementary filter each including a recursive filter and an elementary variable gain amplifier, a control unit for the gain of each elementary amplifier according to a signal coming from the external microphone and an error signal coming from the internal microphone. The processing filter includes an open-loop main filter connected at the input to the external microphone and the output of which is connected, to the adder, and to the input of the or each elementary filter.
Claims10
An audio headset comprising:
- an electro-acoustic transducer placed in a sound-reproduction cavity;
- and
- at least one noise reduction processing chain, each comprising:
- an external microphone for capturing ambient sound exterior to the cavity;
- an internal microphone for capturing internal sound in the cavity;
- a noise reduction processing filter for a signal coming from said external microphone, for producing an external noise reduction signal, the noise reduction processing filter comprising:
- mounted in parallel between said external microphone and an adder at an output of which the external noise reduction signal is obtained, either (i) one elementary filter comprising at least one recursive filter and the elementary filter associated in series with an elementary variable gain amplifier, or (ii) at least two elementary filters mounted in parallel, each elementary filter comprising at least one recursive filter and each elementary filter associated in series with an elementary variable gain amplifier;
- a gain control unit for controlling the gain of each elementary variable gain amplifier according to an external noise reduction target signal coming from said external microphone and an error signal coming from said internal microphone;
- and
- an open-loop main noise reduction processing filter, the input of which is connected to said external microphone and the output of which is connected, both to the adder at the output of which the external noise reduction signal is obtained, and to the input of each elementary filter;
- and
- an amplifier for excitation of said electro-acoustic transducer, from at least the external noise reduction target signal.
Dependencies are inferred from the claim text.