Acoustic echo arise in hand free communication environment due to poor voice coupling between Microphone and Loudspeaker. This paper shows the implementation of Acoustic echo cancellation using gradient based LMS algorithm it also focused on NLMS algorithm to remove the unwanted echo and increase the quality of speech in communication applications . The LMS algorithms uses the estimates of the gradient vector from the available data. LMS and NLMS incorporates an iterative procedure that updates weight vector in the direction opposite of the gradient vector which evenly leads to the minimum mean square error.

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Lms And Lms Algorithm Error Estimation Adaptive Filter