Radio frequency chain of rubidium frequency scale

Abstract

The invention discloses a radio frequency chain of a rubidium frequency scale. A direct digital synthesizer is respectively connected with a voltage controlled crystal oscillator and an acoustic surface wave filter, a radio-frequency amplifier is connected with the acoustic surface wave filter and a phase step diode, a frequency divider is connected with the voltage controlled crystal oscillator, and a single chip microcomputer is connected with the direct digital synthesizer. The output of the 60MHz voltage controlled crystal oscillator is divided into two ways, one way of the output is given to the direct digital synthesizer as a clock signal, and the other way of the output passes through the frequency divider and outputs a 10MHz signal as an output signal of the rubidium frequency scale. A low phase noise reference clock phase locking frequency multiplier is integrated in a chip of the direct digital synthesizer. One way of the output of the 60MHz voltage controlled crystal oscillator passes through the 16 frequency multiplication of a phase-locked loop in the direct digital synthesizer to be a 960MHz clock signal, the 960MHz clock signal is taken as the reference, and the direct digital synthesizer outputs a 179.86MHz signal with square wave modulation. The radio frequency chain is simple in structure, high in integration degree, good in power stability, easy to debug, low in power consumption and low in cost, and has proper phase noise.

Description

technical field [0001] The invention relates to the fields of microwave and atomic frequency standards, and more specifically relates to a radio frequency chain of a rubidium frequency standard, which can be widely used in the fields of radar, miniaturized rubidium atomic frequency standard, variable frequency source and the like. Background technique [0002] The rubidium atomic frequency standard uses double resonance and frequency-locked loop of light, microwave and atom to combine 87 The stability and accuracy of the 0-0 transition line of the Rb atom is transmitted to the local oscillator to form a passive atomic frequency standard. [0003] It has smaller size, lower power consumption, better ability to resist harsh environments, and has better indicators, which can meet the needs of most military and civil projects. It is currently the most widely used atomic frequency standard, accounting for 95% of the current atomic frequency standard market share. It can be used...

AI Technical Summary

Problems solved by technology

However, the inherent characteristics of the phase-locked loop itself make the resolution of the phase-locked frequency synthesizer and the conversion speed inversely proportional to each other

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