Novel frequency stability measurement method with whole sample time range.

A method to measure the frequency stabilities with a nearly whole range of sample time is presented. Precision as high as 10-5/100 ns has been obtained by it when measuring transient stability with 100 ns sample time, 10-12/s has been obtained toward short-term stability with 1 s sample time, and 10-16/day has been obtained with regard to long-term stability with 1 day sample time. In addition, because the frequency stabilities in a wider range of sample time can correspond to the phase noise index more accurately, the phenomena which are difficult to be observed in a phase noise curve can be detected through this measurement.