METHOD AND DEVICE FOR THE DIGITAL CONTROL OF A PHASE-LOCKED LOOP AND RELATIVE PHASE-LOCKED LOOP THUS OBTAINED

摘要

A method is described for the digital control of a phase-locked loop consisting in the separate estimation of both phase and frequency errors of the data source as compared with those of the local oscillator and in the separate a nd adaptive filtering of the two signals. The value of the VCO control voltage is calculated on the basis of the two filtered signals. The phase and frequency err or estimation and the frequency and phase error filtering are carried out in such a way as to eliminate the time-varying random components (jitter and noise) withou t delaying the feedback signals, since the portion of the signals that varies with time because of the variation of the commands, is subtracted before estimations and filterings.