The Research Of Speech Processing In Laser Listening System Based On DSP

In this paper, in order to advance the ability of the laser listening system to resist the atmospheric disturbance and improve the surweillant signal's SNR or definition, the research is aimed at the speech noise.The primary purpose of speech enhancement is to purify it from noise. Because it is very complicated to grasp the random noise's cause or characters, it is impossible to eliminate the random noise completely. Actually, goals of speech enhancement are to improve the quality of speech, to eliminate the background noise so that every hearer is willing to hear and wouldn't feel weary, and to upgrade the quality of speech and understandable level.Most speech signal processing systems are real-time operated. At the same time, along with the development of speech processing technology, and the complicated algorithms, the real-time systems need higher speed to accomplish expected goals. And in recent years, the DSP (Digital Signal Processor) has been well developed which makes speech processing technology also developed fast. As a result, many excellent real-time processing algorithms are realized by high quality Digital Signal Processors.In this paper, firstly, a kind of speech enhancements based on LMS will be introduced, secondly, a speech enhancement arithmetic based on an adjustable step size LMS is put forward which will be carried out by DSP.And the principles of DSP are introduced, especially about TMS320VC5416.The author designed a speech enhancement system and completed the design of hardware. According to the system, we choose the chip around the DSP and success-fully made the hardware, then designed the software of speech enhancement algorithm which is successful in hardware. And this system can restrain noise from noisy speech effectively.