Receive-Path Signal Gain Operations for Echo Reduction

Solution Overview

Problem

Communication devices face challenges in effectively reducing echo signals during communication sessions, particularly in double-talk situations, where both parties speak simultaneously, leading to interference between the receive and transmit audio signals.

Innovation Solution

The system performs gain operations on the receive-path signal by identifying and attenuating frequency components corresponding to echo speech signals while preserving those corresponding to the receive speech signals, using digital signal processing techniques to differentiate between voiced and unvoiced speech for precise amplification and attenuation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If echo cancellation is performed on the receive-path signal, then echo interference is reduced, but the receive speech signal quality deteriorates due to interference during double-talk situations

Engineering Contradiction:

Improveecho interferenceVSAvoidreceive speech signal quality

Core Design Contradiction:

Object-affected harmful factorsVSReliability

Solution Approach 1:

The patent segments the receive-path signal into multiple frequency components, identifying and separately processing echo speech signal components versus receive speech signal components. By dividing the signal processing into distinct frequency domain operations, the system can selectively attenuate echo components while preserving receive speech components, resolving the contradiction between echo reduction and speech quality maintenance.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent applies different gain operations to different frequency components of the receive-path signal. Specifically, it applies attenuation to frequency components corresponding to echo speech signals while applying preservation or amplification to frequency components corresponding to receive speech signals. This localized differential processing resolves the contradiction by treating different parts of the signal differently based on their source.

Inventive Principle:

Principle #3Local quality

2Measurement precision

If gain operations are applied to the receive-path signal, then speech clarity is improved, but echo signals are also amplified causing interference

Engineering Contradiction:

Improvespeech clarityVSAvoidecho signals

Core Design Contradiction:

Measurement precisionVSObject-generated harmful factors

Solution Approach 1:

The patent applies different gain operations to different frequency components of the receive-path signal. Specifically, it applies attenuation to frequency components corresponding to echo speech signals while applying preservation or amplification to frequency components corresponding to receive speech signals. This localized differential processing resolves the contradiction by treating different parts of the signal differently based on their source.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent segments the receive-path signal into multiple frequency components, identifying and separately processing echo speech signal components versus receive speech signal components. By dividing the signal processing into distinct frequency domain operations, the system can selectively attenuate echo components while preserving receive speech components, resolving the contradiction between echo reduction and speech quality maintenance.

Inventive Principle:

Principle #1Segmentation

Data Source

PatentUS11363147B2Receive-path signal gain operations

Publication Date: 2022.06.14 SORENSON IP HOLDINGS LLC

AI summary

Operations related to performing gain operations with respect to a receive-path signal of a first device may be performed. The operations may include obtaining the receive-path signal, which includes an echo speech signal and a receive speech signal originating at a second device. In addition, the operations may include identifying a portion of the receive-path signal that includes, at a particular time, a first frequency component that corresponds to the echo speech signal and a second frequency component that corresponds to the receive speech signal in which the first frequency component is different from the second frequency component. Moreover, the operations may include attenuating the first frequency component of the portion while avoiding attenuating the second frequency component of the portion based on the first frequency component corresponding to the echo speech signal and the second frequency component corresponding to the receive speech signal.