Implementation of low delay cockpit voice encoder for flight data recorder using TMS320C6713 DSP processor

The paper presents a design of low delay audio coding scheme for Flight Data Recorder (FDR) and its implementation on TMS320C6713 DSP processor. The FDR needs very high speed of operation for data storage and maximum compression ratio due to limitation of hardware constraints. MPEG-4 Advance Audio Coder is a very efficient audio compression scheme that suites to the requirements of cockpit voice encoder. In the proposed coding algorithm, odd Discrete Fourier Transform (DFT) has been used in place of Modified Discrete Cosine Transform (MDCT) for filter bank analysis. Synthesis result shows that the proposed coder offers nearly 30% less delay and comparable compression ratio than the standard MPEG-4 audio coder. Further, a hardware implementation of proposed algorithm on DSP board is demonstrated with the promising results.