The Research On Digtal Speech Compression System Based On ARM

With the development of electronic technology and the growing industry demand, the original voice recording device has not been able to fulfill demand for existing applications. Therefore, it is very necessary to develop a new type of voice recording devices. The continuous development of microarray technology and a new manufacturing process also provide technical support to development of voice recording devices. ditional voice recording device used 51 MCU + Speech Codec DSP mode . Speech Codec chip embedded in fixed speech compression algorithm, and 51 MCU control logic process. Due to the restrictions of traditional voice board hardware and software system, we would encounter that storage time is too short, external transmission speed is limited, and many other inconvenient lack of decompression operation in practical.So the new-type voice compression system is imperative.The research ARM-based digital voice compression system ,According to the current existing voice compression system is the problem,Designed with a more powerful processing capability, and more features new voice compression system(1) address the existing system capacity of the system to deal with the shortcomings, we design a new system,amsung S3C2440 is chosen as the main control system chip, use ARM+LINUX structure, lead the handling capacity of the whole system and the ability to external expansion have been greatly improved.(2) with regard to the existing system of a single external communications, storage inadequate short time Taking full advantage of the large-capacity memory, we can achieve a 60-hour store,and also very convenient to extension. By using USB high-speed transfer and the high transmission rate, large capacity storage system does not become a bottleneck. ARM+LINUX system has rich the peripherals, such as Ethernet, CAN, USB, 485 and so on. Compared with traditional system, this one has more transmission ways and more high speed.(3) FPGA chip is used as the main control logic chip,and DSP is used as a speech compression algorithm chip. Through the exchange of data between the three, we can achieve the multi-processor integration platform of ARM+FPGA+DSP.(4) The key speech compression algorithm uses MELP (mixed Excited Linear Predictive Coding) algorithm. It is 2.4K/bps low encoding rate, and maintains well voice quality. Through optimizing algorithm, DSP can handle two voice data at the same time, which greatly enhances practicality.(5) The new platform and software decompression algorithm play a crucial role in the promotion of the new voice recording device.the design of the new issue voice compression system through a rigorous testing and various tests, Various functions and indicators are at the design requirements , Is a perfect substitute for the original voice recording device .