Digital phase-locked loop filter

摘要

A phase processing system which includes at least one digital phase-locked loop wherein the phase of the input signal to the loop is compared with the phase of the loop output signal to produce a pulse-width modulated phase error signal. The error signal is digitally integrated, as by a counting means which cyclically counts the pulse widths thereof and provides a first control signal when the count reaches a first value and a second control signal when the count reaches a second value. The control signals are used to control the pulse rate of a clock signal to produce an intermediate clock signal such that when the first control signal is present a pulse is added thereto and when the second control signal is present a pulse is deleted therefrom. The intermediate clock signal is then fed to a feedback divider counting means which provides the loop output signal.