Acoustic Echo Method Using Least Mean Square Algorithm :Result& Implementation
Keywords:
cancellation, occurrence, telecommunication, delayedAbstract
Acoustic echo cancellation is a common occurrence in todays telecommunication systems. It occurs when an audio source and sink operate in full duplex mode, an example of this is a hands-free loudspeaker telephone. In this situation the received signal is output through the telephone loudspeaker (audio source), this audio signal is then reverberated through the physical environment and picked up by the systems microphone (audio sink). The effect is the return to thedistant user of time delayed and attenuated images of their original speech signal.
Thesignalinterferencecausedbyacousticechois distracting to both users and causes a reduction in the quality of the communication.This thesis focuses on the use of Least Mean Square Algorithm to reduce this unwanted echo, thus increasing communication quality.
Adaptive filters are a class offilters that iteratively alter their parameters in order to minimise a function of the difference betweena desired target output andtheiroutput.Inthe case of acoustic echo in telecommunications, the optimal output is an echoed signal that accurately emulates the unwanted echo signal. This is then used to negate the echo in the return signal. The better the adaptive filter emulates this echo, the more successful the cancellationwillbe.
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