The Embedded Speech Processing System Based On ARM

Recording telephone, tape recording machine controlled by the single chip, magnetic disk or tape controlled by the microcomputer are all used in the speech monitoring systems such as electric systems, rail-way, factory at present, these storage mediums are easily influenced by the surrounding environment like temperature and humidity, so the data tends to be destroyed, lost, short-lifespan conserved and inconvenient monitored and manipulated.The quality of speech recorded in the complicated practical situation such as railway, factory, etc is poor due to the big background noise and the weak speech signal, sometimes the speech signal can not even be clearly obtained. Furthermore, under some conditions, the recorded data is too large that we need high capacity of memory storage, thus the cost of the hardware in the system increases. Digital recording system based on the microcomputer usually belongs to the complicated multi-channel monitoring and controlling of speech system, so the cost is relatively high and is not fitted to the occasions discussed above.Based on the existing condition mentioned above, in this thesis, the principle of embedded system and the algorithm of digital signal processing about noise-immunization and speech compression are studied, in addition, the transplantation of μC/OS-Ⅱ and processing program to ARM microprocessor are realized, a portable and large capacity embedded speech processing system is designed based on the ARM chip and the semiconductor memory technology. The system which is composed of embedded kernel and peripheral circuit can accomplish many manipulations, such as noise immunization, compression, storage, extracting and playing, etc.Moreover, the system has many functions that it can be programmed, the hardware and software can be extended and updated, the data can be highly compressed, speech can be real-time remote inquired and played one by one, data can be exported and restored in the other computers to replay through the interface port.The principal contents of this thesis are as follow:...