Dsp Acoustic Echo Canceling System

Offsetting of echoes has become the bottleneck of the modern comm-unication technology. An acoustic echo cancellation effects the quality o-f telephoning directly. Modern communications is that it's the quickest a-nd most effective means of communication, but this system to introduce more time, the phenomenon of the features that will seriously affect the q-uality of the network.The adaptive technology, which is one of the development trend in t-he future,is applied in the acoustic echo cancellation.It includes two parts: the adaptive algorithm and the detection of the sound.The whole system o-f the convergence of speed, the imbalance of the stationary and the comp-utation complex etc are decided by the adaptive algorithm.The effect of t-he echoes offseting is the key to the detection of the sound.In this article,we studied to the adaptive filter of some of the relevan knowledge firstly,including to filter the basic concepts and implementat-ion of network and the representative of the LMS and RLS algorithm. In modern figures for internet communications, as for the echo,long taps to f-ilter for a computational large problems,find a kind of guarantee the con-vergence and a steady state the case,effectively reduce the degree of com-plexity.This article introduced block of the adaptive filter and fast adapta-tion to filter.On the basis of the LMS algorithm,we start with the researc-h for the bloch adaptive algorithm and the digital signal processing of rela-ted theory.The time-domain block LMS was implemented quieckly in th-e frequency domain Of the block algorithm for the convergence of the sp-eed slackened.In the paper the step size was adjusted by the frequency do-main of the data to improving the FBLMS algorithm.The simulation exa-mination for traditional time-domain LMS and frequeney-domain block LMS with normalized step size and RLS adaptive filtering algorithm wer-e completed in the platform of Matlab. While two algorithms were analyz-ed in the size of computational and convergence speed and stationary imb-alance,have provened superiority by FBLMS algorithm with normalize-d step size.Finally,an acoustic echo cancellation system has been made u -sing TMS320C5416DSP, the system was designed to the echo of the FB-LMS algorithms with normalized step size,based on the Geigel algorit-hm and analyed using CCSlink of Matlab.In the next,an acoustic echoc-ancellation was tested simulatly in the hardware platform of DSP.Testing results indicated that are designed to counteract the echoes meet the requi-rements of the ITU-G.168 actual performance indicators.