A 600bps MELP-Based Speech Quantization Scheme for Underwater Acoustic Channels

The MELP is the U.S. Federal Standard operated at 2.4kbps, it could achieve equal to or better than the performance of the 4.8kbps CELP vocoder. However, for channels like underwater acoustic channel, the condition is very bad that even the 2.4kbps MELP data could not be transferred. A new 600 bps quantization method based on the MELP parameters is proposed. The new scheme contains methods like inter-frame prediction, linear interpolation and so on. Though the bit rate is only a quarter of the original MELP algorithm, the scheme could also synthesize a reconstruction speech which is understandable.