Multistage selective differential pulse code modulation system

摘要

A differential pulse code modulation system, in which an input signal is at first approximated to a stepwise waveform having level changes at a constant number n of sampling points selected in the order of level magnitude from a predetermined number N of samples in the input signal. The remainder of the above approximating operation is secondary followed-up by delta modulation, which uses a variable step level controlled in accordance with the variation feature of the remainder. The differential pulse code modulation output is provided by the above two approximating operations.