Mobile Terminal Acoustic Echo Control Using Distributed Reference Signals
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Distributed voice conferencing systems face challenges with acoustic echo due to spatial audio processing, where echo signals from one mobile terminal are not effectively attenuated by other devices in the same acoustical space, disrupting communication quality.
Innovation Solution
The method involves each mobile terminal receiving reference signals for downlink audio from other devices, processing echo signals using adaptive filters to attenuate echoes from both its own and other devices' audio transducers, ensuring reduced echo signals are transmitted during distributed voice conferencing sessions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If spatial audio processing is used in distributed voice conferencing, then speech intelligibility and speaker identification are improved, but acoustic echo from other devices is not effectively attenuated
Solution Approach 1:
The patent segments the echo attenuation function by providing each mobile terminal with reference signals from multiple sources (its own downlink audio and downlink audio from other terminals). Each terminal independently processes these segmented reference signals through adaptive filters to address echoes from different sources, rather than relying on a single centralized echo cancellation approach.
Solution Approach 2:
The patent applies preliminary action by providing reference signals to each mobile terminal before echo attenuation is needed. The host device generates and distributes reference signals containing downlink audio from multiple terminals in advance, enabling each terminal to pre-configure its adaptive filters for effective echo cancellation when spatial audio processing is active.
2Measurement precision
If each mobile terminal uses its own loudspeaker and microphone for distributed conferencing, then speech quality on the far end is improved, but acoustic echo control becomes more complex
Solution Approach 1:
The patent applies universality by making each mobile terminal multi-functional: each terminal not only processes its own downlink audio for echo cancellation but also receives and utilizes reference signals from other terminals. This universal approach allows each device to handle multiple echo sources simultaneously, simplifying the overall system architecture while maintaining effective echo control across all terminals.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach effectively reduces or eliminates acoustic echo signals, enhancing communication quality by leveraging spatial audio processing while maintaining improved speech intelligibility and speaker identification.
Implementation Method 1
Acoustic echo control (AEC) has been developed in order to attenuate the acoustic coupling between the audio signals reproduced by the loudspeaker and the audio signals received by the microphone of the same device. AEC generally utilizes an adaptive filter positioned between the downlink and uplink signals
Implementation Method 2
AEC generally utilizes an adaptive filter positioned between the downlink and uplink signals followed by a residual echo suppression unit
Data Source
AI summary
A method, apparatus computer program product provide acoustical echo control for distributed voice conferencing including distributed voice conferencing that utilizes spatial audio processing. In the context of a method, a reference signal and one or more other reference signals may be received by a mobile terminal. The reference signal is associated with downlink audio to be reproduced by the mobile terminal and the one or more other reference signals are associated with downlink audio to be reproduced by one or more other mobile terminals. The method also includes processing an echo signal from uplink audio due to the downlink audio reproduced by the audio transducer of the mobile terminal based upon the reference signal. The method also processes an echo signal from uplink audio due to the downlink audio reproduced by respective audio transducers of the one or more other mobile terminals based upon the one or more other reference signals.