A New Method Of Determining The Performance Of Delta Modulation Systems

A formula for signal to quantizing noise ratio in delta modulation systems is derived assuming only stationarity of the signal source. The three interesting terms in this expression are examined as a function of quantizing step size and relative sampling rate for three types of signal inputs. Computer simulation is used to obtain empirical results concerning the behavior of the three terms and a qualitative explanation for this behavior is offered. The analysis is undertaken from a total quantizing noise point of view; this gives an insight into system behavior that cannot be obtained by considering the effects of the signal-correlated and signal-uncorrelated components of quantizing noise separately. (Author).

Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.

Delta Modulation Systems.- Some Existing Approaches of Linear Arithmetic Operations on Binary Delta Modulated Pulse Stream.- Basic Ternary Logic Circuits.- Arithmetic Operations on Multi-Valued Delta Modulation Systems.- Nonlinear Arithmetic Operations on Delta Modulated Pulse Stream.- Mixed Processing of Delta Modulated Pulse Stream.- Decoding of First Order Delta-Sigma Sequences.- PCM - Delta-Sigma-Mu Converters.- Stochastic Processing using Delta-Sigma-Mu.- Measurements Based on Delta Modulation.- Delta-Sigma Compander Circuits

The report describes the results of a study of Statistical Delta Modulation (SDM) a new mthod of digital transmission of analog information. In this method the system design is tailored to the statistical properties of the input data so as to provide analog reconstruction values with a minimum mean squared error. The method of system design is an iterative procedure in which conditional means are evaluated based upon actual input data. The report presents the theory of operation of the system and describes the results of a computer simulation in which such questions as the effects of sampling rate, channel noise, system memory, and mismatched input processes are discussed. Due to time limitations only a brief comparison was made with conventional techniques. It was found that at low sampling rates and for a second order Gaussian Markoff process, sampling rate reductions of 38% could be achieved relative to a conventional delta modulation system at the same SNR performance. (Author).