A 32 KBPS codec for satellite communication

A 32 kbps ADPCM codec has been developed by combining a robust predictor with a predictor-driven locking quantizer. The algorithm has been chosen through careful studies on combinations of several prediction algorithms and a dynamic locking quantization scheme. By introducing a new speech and data discrimination function in the prediction algorithm, high performance encoding capability very close to that for 64 kbps PCM on both speech and modem signals has been realized without losing robustness in its ability to operate properly in spite of transmission bit errors. This codec enables channel capacity doubling in any digital network, including satellite communications.