RESPONSE OF DELTA MODULATION TO GAUSSIAN SIGNALS

Analytical, experimental, and computer simulation results are given for the error spectrum of a delta modulator when probed by stationary, band limited, gaussian noise. These three complementary methods are used to increase our quantitative understanding of the nonlinear system with memory. The error is conveniently split into two components: one linearly dependent on the input signal and one linearly independent of the input signal. In order to isolate these two types of errors we use two measurement techniques. For purposes of analysis we show that the delta modulator can be replaced by an equivalent linear system with additive noise at its output which is linearly uncorrelated with the input. The equivalent linear system may be approximated by using methods involving statistical linearization or the deterministic describing junction. Alternately, the equivalent linear system may be obtained from computer simulation. © 1969 The Bell System Technical Journal