JPS6489619A - Phase locked loop oscillator - Google Patents

Abstract

PURPOSE:To suppress the accumulation of output phase fluctuation by providing a means to measure a time, in which the fluctuation of the central frequency of a phase locked loop oscillator goes to be the integer-fold output frequency control resolution, and a means to detect a control value, in which an output frequency goes to be higher than an input reference clock frequency, and a control value in which it goes to be lower. CONSTITUTION:This device is composed ot a phase comparator 1, a processing circuit 2, a rubidium optical transmitter 3 and a phase locked loop oscillator 4. In this constitution, a phase difference between a reference input clock fin and an output clock fo is detected by the phase comparator 1 and the processing circuit 2 calculates the control value from the detected result. The output clock fo is made by a rubidium oscillator 3, which goes to be a reference oscillator at a selftraveling time, and the phase synchronizing oscillator 4 to be synchronized to it. For the phase locked loop oscillator 4, since an output clock frequency is controlled by the above mentioned control value, the output clock fo is synchronized to the rubidium oscillator 3 and the input clock fin.