Response of Delta Modulation to Gaussian Signals

1.1 General Background and Broad Objectives Delta modulation (DM) has been known for almost two dccades; yet, little has been published comparing experiment with theory particularly for random inputs.f On the surface this might seem strange because of the apparent simplicity of the delta modulation system blocked out in Fig. 1(a). The waveforms depicted in Fig. 1(b) and the mathematical model in Fig. 1 (c) should suffice to explain how the system operates. The principal difficulty of the analysis is the absence of general tools for handling random processes in nonlinear systems with memory. From this viewpoint the simplicity of the delta t The first reference to delta modulation appeared in French patent literature (see Ref. 1) in 1946, but the first readily available description in English appeared in 1952 (see Ref. 2). 1167 1168 T H E BELL SYSTEM T E C H N I C A L J O U R N A L , M A Y - J U N E 1969 modulator is deceptive. However, if we make some inroads into the quantitative understanding of this seemingly simple case, it may give us courage to go on to more complicated situations. In this paper we concentrate on the development and exploitation of analytical, experimental, and computational techniques to enhance our understanding of the objective performance of delta modulation. We do not consider the correlation of objective measures with subjective effects for applications to either voice or video; rather, our main aim is to correlate what is known in theory, including our own developments with what has been achieved experimentally.