Assistant Professor,Electronics and Communication

Abstract. In acoustic echo cancellation the highly correlated speech input signal and very large impulse response path of echo signal will slow down the convergence rate of adaptive filters if full band adaptive filter is used. To solve these problems sub band adaptive filters are used. Adaptive combination methods provide an interesting way to improve adaptive filter’s performance. Adaptive combination of normalized sub band adaptive filters is used. In our proposed method, adaptive combination of sub band signals before going to the adaptive filters. Experimental results show that the combination method can obtain both fast convergence rate and small steady state MSE by using less number of adaptive filters by adjusting step size parameter and mixing parameter