Digital to analog decoder.

摘要

A digital to analog decoder converts an input digital signal into an output analog signal and alters the spectral content of the output signal. An adaptive delta demodulator (42) converts the input digital signal into an analog signal to provide the output analog signal in accordance with a step-size control signal (28). Processing means (96) alter the spectral content of the output signal in accordance with a spectral control signal (82). The step-size and spectral control signals both have limited bandwidths (46, 80) so that substantially the same output signal is obtained irrespective of the order in which the delta demodulation (42) and altering of the spectral content (96) are performed.