Dithering Control of Oscillator Frequency to Reduce Cumulative Timing Error in a Clock

摘要

A method for correcting time error in an oscillator operated clock according to one aspect of the invention includes at selected times determining at least one of a time error in the clock and a frequency difference between the oscillator and a reference oscillator by detecting a time reference signal. A change in the at least one of the time error and the frequency difference between a first one and a second one of the detecting the time reference signals is determined. A frequency of the oscillator is adjusted so as to substantially cancel a cumulative time error between the second one of the detecting the time reference signal and a selected detecting the time reference signal.