On Soft-Decision Demodulation for PCM- and DPCM- Encoded Speech

In a simulation of soft decision demodulation-interpolation for digital speech transmission, it has been noted that signal-to-noise ratio gains due to the technique are greater with nonadaptive and periodically adaptive quantizers than with instantaneously adaptive quantizers; further, the gains are greater with PCM than with differential PCM. Our results for nonadaptive PCM reinforce those in a recent analytical paper by Sundberg [1].