Flight Parameter Design And Implementation Of The System Of Record Voice Codec

In the paper, A voice codec that used in the flight data recorder (FDR) system was designed , The Codec is used to recorde the voice of cockpit in real time. It give the design of the codec's software and hardware . On the basis of the linear- prediction coding the code excited linear- prediction coding was analyzed. The software is based on A speech coding standard named conjugate structure algebraic-code-excited linear-prediction(CS-ACELP). An advanced digital signal processor (DSP) is selected as the main processor of the coder on the FDR. In order to give the DSP more time to compute an circuit can accomplish the A./D conversion the speech signal and buffer the digital speech signal datas in the FIFO memory temporarily was designed. Experiments proved that the codec can recode four channels speech in real time and the quality of the recovered speech is satisfying. And the design intention is realized.