VOIP Acoustic Echo Cancellation To The Research Based On Normalized Algorithm

With today's rapid development of network technology, the case of widely available Internet, IP Phone has good prospects for development. Especially for mines and other wired LAN has been built or wireless local area network of industry-specific environmental, the application has its own unique advantages. Therefore, to carry out based on wireless IP voice calls technology research has a good practical application of important the oretical significance and research value. VoIP application of echo cancellation is an important basic algorithms, for improving the practical application experience of VoIP phone, to really bring to the practical application has great significance. It is more difficult and costly for VoIPPhone hardware echo cancellation, relatively speaking, the software can save the cost, Software implementation of the algorithm is mainly improved, there is some flexibility for users, users only need to adjust the parameters in the echo cancellation algorithm, to achieve the purpose of better Echo cancellation.First, it illustrates the source, purpose and the significance of the paper; Secondly, it discussed in detail of the development of IP phone background,development,coding techniques and technology development,working principle,system and network hardware and software implementation of telephone equipment design functions. Then it described of the basic concept of VoIP,voice recognition,system components,key technologies,features and principles of echo cancellation, In order to improve the echo of the program this paper uses LMS adaptive filtering algorithm and normalized LMS adaptive filtering algorithm. Focus on detailing the LMS (Least Mean Square, LMS algorithm)adaptive filtering algorithm works,performance analysis,the core of LMS algorithm and normalized LMS algorithm. And compared with the classical RLS, LMS Newton adaptive filtering algorithm's advantages and disadvantages.Using MATLAB simulation tool for the text proposed by the two algorithm for emulation experiment and performance analysis. Proved to be based on a LMS algorithms are regulated on the speed and to improve performance, To modular design Of echo cancellation technology in the mines on the application of DSP platform; Finally, the full text is summarized and outlooked.