Scdma System Software Of The Speech Coding Algorithms To Achieve

Compressed coding of speech signals is one of the efficient methods to improve the capacity of channels. With the rapid development of communication technology, we need lower coding rate for speech communication without changing the speech quality. So we can save frequency resource for communication. Under this condition, speech coding technology develops fast. Many international standards come out one by one. They are widely used in communication, B-ISDN and multimedia etc. In this paper, I mainly research the standard of G.729 for speech compressed coding, which is constituted by International Telecommunication Union. At the same time, I realize the standard in real time by using of the fixed-point DSP chip- TMS320LC549. The Conjugate-Structure Algebraic Code-Excited Linear Prediction (CS-ACELP) arithmetic is used in the standard of 0.729. This arithmetic has low delay and high reconstructed speech quality. It can save greatly the comparatively congested frequency resource especially in the mobile communication field.