Accession Number : AD0437495


Title :   SUPPRESSION OF NOISE EFFECTS IN PULSE WIDTH MODULATED SYSTEMS,


Corporate Author : ILLINOIS UNIV URBANA COORDINATED SCIENCE LAB


Personal Author(s) : Stein,H J


Report Date : Jan 1964


Pagination or Media Count : 55


Abstract : Investigation is made of a sampled data feedback system, consisting of a lead type pulse width modulator, a general (n-th order), linear, timeinvariant plant, and unity feedback. The closed loop system is assumed to be stable, and it is assumed that plant time constants are of the order of, or shorter than, the pulsing period. The modulator is assumed to be imperfect (noisy), in that it emits pulses, the durations of which differ from the correct values. The deviation of the pulse width is assumed to be a Gaussian random variable with zero mean and a given standard deviation, and it is assumed that there is no correlation between samples at different sampling instants. Equations are derived which predict the probability distribution of the plant output after any number of sampling instants. (Author)


Descriptors :   *NOISE(RADIO) , PULSE MODULATION , CONTROL SYSTEMS , SAMPLING , FEEDBACK , EQUATIONS , PROBABILITY , MATHEMATICAL ANALYSIS , STATISTICAL PROCESSES


Distribution Statement : APPROVED FOR PUBLIC RELEASE