Frequency synthesizer for normalizing the frequency and time scales of crystal clocks on orbiting satellites

Crystal oscillators used in orbiting satellites to provide a working time scale are subject to drifts in frequency that cannot be predicted more than a few days at a time. A frequency synthesizer has been developed that will translate the input frequency to the output frequency according to precise mathematical formulation. This device provides the means to convert the satellite crystal oscillator to a prescribed frequency that will make the satellite clock agree in rate to clocks on the ground. A frequency tuning span of 65 parts per million is covered in 38 million discrete steps. The movement across this tuning range in the satellite is controllable from the ground either to specific steps or to a rate of progression through the steps. Short term instabilities attributed to the synthesizer have a one sigma deviation of 1 part in 100 billion averaged over 1 second.