Active noise cancellation in audio output device

Patent metadata

Field	Value
Publication number	US-2016240185-A1
Application number	US-201615044381-A
Country	US
Kind code	A1
Filing date	Feb 16, 2016
Priority date	Feb 16, 2015
Publication date	Aug 18, 2016
Grant date	—

Abstract

An audio output device controls the application of active noise cancellation (ANC) levels based on a current status of the device. The audio output device includes a communication interface configured to provide a wired or wireless connection to a playback device, a signal detector configured to detect an audio signal provided through the communication interface, an ANC module configured to apply a first-level ANC to the audio signal, and a control unit configured to determine a level of the ANC to be applied by the ANC module. Upon determining that the audio signal is not provided based on information provided from at least one of the communication interface or the signal detector, the control unit instructs the ANC module to perform a second-level ANC.

First claim

What is claimed is:

1 . An audio output device comprising:
a communication interface including one or more of a wired or wireless connection to a playback device; a signal detector configured to detect an audio signal received through the communication interface; a control unit configured to determine a particular level of active noise cancellation (ANC) to be applied to the audio signal; an ANC module configured to apply the particular level of ANC determined by the control unit, wherein the ANC module applies a first-level ANC to the audio signal; and if the control unit determines that the audio signal has not been detected based on information received from at least one of the communication interface and the signal detector, the control unit controls the ANC module to perform a second-level ANC.

2 . The audio output device of claim 1 , wherein the ANC module performs the second-level ANC to the audio signal by increasing a gain of a microphone connected to the ANC module to be higher than a gain for an application of the first-level ANC.

3 . The audio output device of claim 2 , wherein the ANC module receives a noise through the microphone and performs the ANC on the noise in a feedforward, feedback, or hybrid manner.

4 . The audio output device of claim 1 , further comprising a noise reducer configured to remove a noise generated due to performance of the second-level ANC.

5 . The audio output device of claim 4 , wherein the noise reducer comprises a notch filter circuit, and wherein the notch filter circuit is configured to remove a hissing noise generated by performance of the second-level ANC.

6 . The audio output device of claim 1 , wherein the control unit determines the particular level of the ANC to be applied by the ANC module as the second level upon receiving, from the communication interface, information indicating that the wired or wireless connection is not established between the audio output device and the playback device.

7 . The audio output device of claim 1 , wherein the control unit determines the level of the ANC to be applied by the ANC module as the second level upon receiving, from the communication interface, information indicating that the audio output device is connected to the playback device by wire and receiving, from the signal detector, information indicating that a level of the audio signal is lower than a threshold value.

8 . The audio output device of claim 7 , wherein the communication interface further comprises an ear connector including at least four poles for the wired connection to the playback device, and
wherein, if a connection to a microphone terminal of the ear connector is detected, the communication interface outputs to the control unit, information indicating that the audio output device is connected to the playback device by wire.

9 . The audio output device of claim 1 , wherein the control unit determines the level of the ANC to be applied by the ANC module as the first level upon receiving, from the communication interface, information indicating that the audio output device is connected to the playback device wirelessly and receiving, from the signal detector, information indicating that a digital audio signal is received through the wireless connection.

10 . The audio output device of claim 1 , wherein the communication interface provides to the control unit an audio codec on/off information of the playback device received from the playback device, and
wherein the control unit determines the level of the ANC to be applied based on the audio codec on/off information.

11 . An audio output device comprising:
an active noise cancellation (ANC) module configured to perform ANC using a noise received through at least one microphone; and a control unit configured to determine a gain of the at least one microphone, wherein the control unit determines the gain of the microphone as a first level of gain if it is determined that an audio signal is received from a playback device connected to the audio output device by wire or wirelessly, or the control; unit determines the gain of the microphone as a second level of gain if the audio signal is not received from the playback device, and wherein the second level of gain is higher than the first level of gain.

12 . The audio output device of claim 11 , wherein the control unit determines the gain of the microphone as the second level if the playback device is not connected to the audio output device by wire or wirelessly.

13 . The audio output device of claim 11 , wherein the audio output device includes a switch module having an input terminal connected to the ANC module and an output terminal selectively connectable to an output unit or to a noise reducer circuit, and
wherein, if the control unit determines that the audio signal has not been transferred, the control unit controls the switch module so that the ANC module is connected to the noise reducer.

14 . The audio output device of claim 11 , wherein the control unit determines the gain of the microphone based on audio codec on/off information received from the playback device by wire or wirelessly.

15 . An active noise cancellation (ANC) method of an output device, comprising:
determining a state of connection of a communication interface between a playback device and the output device; detecting an audio signal received through the connection; determining a particular level of ANC to be applied based on at least one of the state of the connection or state of the audio signal; and performing the ANC at a determined level on a signal to be output.

16 . The ANC method of claim 15 , wherein the performing the ANC comprises:
setting a gain of a microphone connected to an ANC circuit based on the particular level; receiving a noise through the microphone; and applying the ANC to a signal to be output based on a value of the received noise.

17 . The ANC method of claim 16 , wherein the performing the ANC further comprises reducing a noise generated due to application of the ANC using a noise reduction filter, with respect to the signal to which the ANC is applied.

18 . The ANC method of claim 15 , wherein the performing the ANC comprises applying a first level of the ANC to the audio signal if it is determined that the playback device is connected to the output device and the audio signal is provided from the playback device to the output device.

19 . The ANC method of claim 18 , wherein the performing the ANC comprises applying a second level of the ANC to an output signal if it is determined that the playback device is connected to the output device but the audio signal is not provided from the playback device to the output device,
wherein the second level of ANC causes a larger amount of a frequency response distortion compared to the ANC of the first level.

20 . The ANC method of claim 19 , wherein the performing of the ANC comprises applying the second level of the ANC to the output signal if it is determined that the playback device is not connected to the output device.

Assignees

• Samsung Electronics Co Ltd

Inventors

• Park Cheol Yong
• Chang Ju Hee
• Na Se Jeong
• Park Sung Kyu
• Shim In Seok
• Jeong Sung Hoon
• Hwang Ho Chul

Classifications

• G10K2210/3016

  Control strategies, e.g. energy minimization or intensity measurements · CPC title

• H04R1/1041

  Mechanical or electronic switches, or control elements (switches in general H01H) · CPC title

• H04R2460/01

  Hearing devices using active noise cancellation · CPC title

• G10K11/1782 Primary

  Physics · mapped topic

• H04R2420/05

  Detection of connection of loudspeakers or headphones to amplifiers · CPC title