CLAIM OF PRIORITY

This application is a National Phase Entry of PCT International Application No. PCT/KR2018/010038, which was filed on Aug. 30, 2018 and claims a priority to Korean Patent Application No. 10-2017-0112714, which was filed on Sep. 4, 2017, the contents of which are incorporated herein by reference.

TECHNICAL FIELD

Various embodiments relate to a signal processing method and electronic device for removing an echo signal being a sound that is again introduced into the electronic device after being reproduced by the electronic device.

BACKGROUND ART

An electronic device provides various calling schemes in a communication environment with another electronic device. For example, the electronic device provides a speaker phone call and/or a video call. In this calling scheme, the electronic device outputs, through a speaker, a sound signal received from the another electronic device. The outputted sound signal may be again introduced into the electronic device through a microphone of the electronic device. In other words, the electronic device may receive an echo signal (i.e., reverberation signal) that is the sound signal outputted through the speaker. The echo signal is a main cause of deteriorating a sound quality. Accordingly, the electronic device removes the echo signal by using a signal processing technique (e.g., echo cancellation) configured to remove the echo signal at calling.

DISCLOSURE OF INVENTION

Technical Problem

A feed-back modeled to remove a reverberation signal (or echo signal) of an electronic device has an attribute of linearity. Meantime, the reverberation signal can include a non-linear signal provided through an element, etc. of the electronic device. In this case, the modeled feed-back removes only a linear component of the echo signal, and there is a problem that it is difficult to remove the non-linear signal of the echo signal.

Various embodiments may provide an electronic device and method for modeling a non-linear signal among an echo component introduced into the electronic device, based on non-linear modeling, to remove the non-linear signal.

Various embodiments may provide an electronic device and method for removing a non-linear signal introduced into the electronic device, based on a filter having an attribute of non-linearity and a filter having an attribute of a neural network.

Solution to Problem

In various embodiments, an electronic device may include an audio input module, an audio output module, and a processor. The processor may be configured to identify a first audio signal that will be outputted through the audio output module, and provide a first signal into which the first audio signal is processed by using a first filter having a first attribute of non-linearity and a second signal into which the first audio signal is processed by using a second filter having a second attribute of non-linearity, and output the first audio signal through the audio output module, acquire an external audio signal comprising the first audio signal of the electronic device, through the audio input module, and acquire a first output value through a first input channel of an audio filter in which a first weight having a first non-linear characteristic is applied to a magnitude value corresponding to a first frequency among the first signal and a magnitude value corresponding to the first frequency among the second signal, acquire a second output value through a second input channel of the audio filter in which a second weight having a second non-linear characteristic, distinct from the first weight, is applied to a magnitude value corresponding to a second frequency among the first signal and a magnitude value corresponding to the second frequency among the second signal, and provide a second audio signal, based at least on a first difference value between the magnitude value corresponding to the first frequency of the external audio signal and the first output value and a second difference value between the magnitude value corresponding to the second frequency of the external audio signal and the second output value.

In various embodiments, a method of an electronic device may include identifying a first audio signal that will be outputted through an audio output module, and providing a first signal into which the first audio signal is processed by using a first filter having a first attribute of non-linearity and a second signal into which the first audio signal is processed by using a second filter having a second attribute of non-linearity, and outputting the first audio signal through the audio output module, and acquiring an external audio signal comprising the first audio signal of the electronic device, through an audio input module, and acquiring a first output value through a first input channel of an audio filter in which a first weight having a first non-linear characteristic is applied to a magnitude value corresponding to a first frequency among the first signal and a magnitude value corresponding to the first frequency among the second signal, and acquiring a second output value through a second input channel of the audio filter in which a second weight having a second non-linear characteristic, distinct from the first weight, is applied to a magnitude value corresponding to a second frequency among the first signal and a magnitude value corresponding to the second frequency among the second signal, and providing a second audio signal, based at least on a first difference value between the magnitude value corresponding to the first frequency of the external audio signal and the first output value and a second difference value between the magnitude value corresponding to the second frequency of the external audio signal and the second output value.

In various embodiments, an electronic device may include an audio input module, an audio output module, a memory storing instructions, and at least one processor. The at least one processor may be configured to execute the stored instructions so as to output a first audio signal through the audio output module, and model the first audio signal through a non-linear filter, based on an attribute of non-linearity, and model the first audio signal modeled based on the attribute of non-linearity, into a second audio signal, based on an attribute of linearity, through a linear filter, and model the first audio signal modeled based on the attribute of non-linearity, into a third audio signal through a neural network, and, in response to receiving an external audio signal related with the first audio signal through the audio input module, process the received external audio signal, based on the second audio signal and the third audio signal.

Advantageous Effects of Invention

According to various embodiments, the electronic device and an operation method thereof according to various embodiments may effectively remove an echo signal that a sound reproduced with a speaker is again introduced into a microphone in the electronic device including the speaker and the microphone.

According to various embodiments, the electronic device may forward only a target voice signal at voice recognition or calling of the electronic device, through effective echo signal removal, to more improve a voice recognition function, and prevent a deterioration of a sound quality beforehand.

According to various embodiments, the electronic device may real-time model and remove a non-linear signal among an echo component.

According to various embodiments, the electronic device may remove non-linearity provided in a speaker and a microphone, to improve non-linear modeling performance through modeling that uses a plurality of non-linear attribute filters (or sigmoid functions) having mutually different features.

According to various embodiments, the electronic device may improve non-linear modeling performance by using a filter having an attribute of a neural network at a frequency axis for a non-linear echo modeled by a plurality of non-linear attribute filters (i.e., sigmoid functions). According to various embodiments, the electronic device may minimize connection between a node of a neural network and a node while improving the non-linear modeling performance, to reduce real-time operation amount and memory use.

An effect that may be obtained from the present invention is not limited to the effects mentioned above, and other effects not mentioned would be able to be apparently understood from the above statement by a person having ordinary skill in the art to which the present disclosure pertains.

