Research And Simulation Of Speech Coding Algorithm Based On MELP

Speech Coding is of great importance for many applications in the digital communica tion system. At the situation where the transmission rate is limited very strict, Low Bit Rate Speech Coding is especially of important significance.Mixed Excitation Linear Prediction coder which adopted as the new U.S. Federal Standard at 2.4kb/s is one of the best coders currently.This article analyzes the theory of MELP, Including the procedure of coding and decoding. A concept of similarity is applied to pitch detection and correlation between successive frames. This method not only gives a simple and effective pitch detection way but also reduces the transmission bit rate of the coding system. In chapter one, we briefly introduce the developing status of the technology of voice coding and decoding, the method of appraising the performance of voice coding and the structure of this paper. Chapter two shows the general situation and the new five characters of MELP. In chapter three, the definition of similarity and its application is introduced. We introduce the coding procedure and the decoding procedure in chapter four.