Robust Speech Coding Algorithm
Speech communication in Electronic Warfare (EW) environment should be resistant to interception, masquerade and tolerant to communication channel errors. In this paper, the authors described an algorithm which provides speech compression, strong encryption, error tolerance and speaker authentication features. This Robust Speech Coder (RSC) is backward compatible with the existing codecs with capability to opt for additional features as and when required. Speech coders are classified into waveform coders, parametric and hybrid coders. Waveform coders like Pulse Code Modulation (PCM) and Adaptive Differential PCM (ADPCM) attempt to preserve the original shape of the input signal and work at bit rate of 32 kbps and above.