Research And Realization Of Voice Signal Recognition System Based On DSP

Speech Recognition is the best way of the personal-machine communication.By the development of computer technology, It has been implemented into product in many areas such as control, communication and consumption Not only is speech recognition a theoretical problem, but also an engineering problem. It integrates theoretic achievements of many disciplines, for example, acoustics, phonetics, linguistics, physiology, digital processing, information engineering, computer science,pattern recognition and artificial intelligence. Speech recognition technology developed to cater for the usual application . But the speech recognition system in the commercialization process there, such as the recognition speed (real time), robustness of the system and higher rates of specific issues identified . How to improve the performance of speech recognition systems, the system faster and more stable employment is the focus of the study.How to make the speech recognition put to practical uses is the hotspots of current research of speech recognition technology.This thesis makes some discussion on speaker-independent isolated word speech recognition system in this case.The thesis first introduces the background and significance of the subject. Focus on speech recognition technology from the status quo and the current speech recognition technology challenges two aspects of the narrative. Which describes the subject of research.Secondly, The thesis introduces the elementary theory of isolated word speech recognition system and analyses the basic work process of isolated word speech recognition. Then it introduced the characteristic parameters and isolated word speech recognition algorithms in common use, and carrying on the comparison to the all.According to the comparison results and considering this system's characteristic,it adopts MFCC characteristic parameters and the classical dynamic time warping (DTW) recognition algorithm to improve recognition rate.In this paper,it proposes the noise short-term energy endpoint detection method ,and using MATLAB7.1 software simulation.As for hardware design aspect, it elaborates the system constitution of isolated word speech recognition, which taking TMS320C6713 DSP as the processing center, and gives concrete hardware design of every part. The hardware system is mainly composed of four major modules: DSP module, voice acquisition and processing module, spread memory module (SDRAM and FLASH ROM and SD card), the power supply module and micro-controller module.As for software design aspect,aiming at the characteristic of isolated word recognition, it elaborats the design process of system software. The software design is primarily includes the following areas: speech signal conditioning, activity detection, feature extraction, establish a voice template library, pattern matching, etc. In the software design processing, It also gives the flow chart of every part about speech recognition and the simulation results of every part by using MATLAB7.1 software. It also elaborates the guidance loading procedure's design process of TMS320C6713 with external FLASH. According to software system debugging, the speech recognition system has a higher recognition rate .