APPARATUS AND METHOD FOR MICROWAVE FIELD STRENGTH STABILIZATION IN CELL TYPE ATOMIC CLOCKS

摘要

The microwave field intensity of a cell type atomic clock is stabilized through time division feedback control of the power of the microwave signal implemented by a microcontroller. The depth of the microwave dip is calculated from differences in measurements of the optical signal when the microwave signal is dithered around the atomic transition frequency of the active medium, and measurements taken when the optical signal is dithered around the optical wavelength of the active medium while the microwave signal is adjusted to produce no microwave absorption, either by reducing the microwave power to zero or by detuning it from the atomic transition frequency of the active medium. RF synthesizers suitable for regulating microwave power include a synthesizer using a step recovery diode for frequency multiplication and having the power to a driver amplifier or the bias applied to the diode regulated. A digital synthesizer can also be used to generate a regulated microwave signal.