Abstract: An electro-optic delay line frequency discriminator has an optical signal source providing first and second optical signals that are directed along first and second paths, respectively. In the first path, the first optical signal is converted to a first corresponding optical signal that corresponds to an electrical input signal, and the first corresponding optical signal is then delayed. In the second path, the second optical signal is delayed, and the delayed second optical signal is then converted to a second corresponding optical signal that corresponds to the electrical input signal. The first and second corresponding optical signals are converted to first and second corresponding electrical signals, respectively; and a detector, responsive to the first and second corresponding electrical signals, provides an electrical output signal from the discriminator. Optical source relative intensity noise (RIN) is canceled out and does not degrade the signal-to-noise ratio of the discriminator output.

Abstract: An RF chain having a high-frequency oscillator providing first, second and third outputs. The first output is multiplied to provide a microwave signal to an atomic beam tube; the second output is divided to provide a standard output frequency; and the third output is divided to provide a first input to a phase detector. The phase detector receives a second input from a low-frequency oscillator which is controlled by a servo signal from the atomic beam tube. The output of the phase detector provides a control signal to the high-frequency oscillator.