Multi-band Excitation Speech Encoder And Broadband Voice Applications

In this paper, the author research, simulate and improve the Multiband Excitation speech coding algorithm. First, the principle of Multiband Excitation Model and its analytical and synthetical method are presented. MBE applies a new excitation spectrum, thus it provides high quality speech reproduction for both clean and noisy speech. It is a relatively ideal speech coding algorithm at low rate. Second, this paper illustrates the simulation of MBE encoder and provides the flow chat of the program and the result of the simulation. The coding and decoding method is also given. Based on the simulation of the algorithm, the application of the algorithm is analyzed. The result shows the synthetical speech and the original speech are similar on the time region and the frequency region, and the synthetical speech is of high definition and understandable, so the speaker can be easy to be distinguished. But it needs relatively long time delay. At last, the author apply the algorithm on wide-band speech. In order to reducing the amount of computation and the time delay of this algorithm, some improved measures are proposed. In the end of the paper, the author points out the direction of the research work in the future.