Investigation of an Optimum Sampling Interval for a Local Clock TIE Model with an Unbiased FIR Filtering Algorithm

Abstract

An investigation of the optimal time step (sampling interval) is provided for the time interval error (TIE) model of a local crystal clock in GPS-based timekeeping. For the sawtooth noise of a receiver, the local clock states are estimated employing an unbiased finite impulse response (FIR) filtering algorithm. We exploit the local crystal clock imbedded to the Stanford Frequency Counter SR620. The measurements are provided using the SynPaQ III GPS Sensor as a timing receiver and rubidium clock (SR625) as a reference source of time for the crystal clock