New TWELP 2400 bps Robust and 4800 bps Robust vocoders provide highest speech quality in very noisy channel- much better than any known vocoders as, for example, MELPe 2400 bps and GSM AMR 4750 bps vocoders respectively.
TWELP 2400 bps Robust vocoder
TWELP 4800 bps Robust vocoder