【摘 要】
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Microwave oscillator based on cryogenically cooled sapphire cavity has advantages of extremely high-Q factor and low noise,thus it has a wide application prospect.On the basis of theoretical calculati
【机 构】
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Beijing Institute of Radio Measurement and Metrology,Beijing 100854,China
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Microwave oscillator based on cryogenically cooled sapphire cavity has advantages of extremely high-Q factor and low noise,thus it has a wide application prospect.On the basis of theoretical calculation by HFSS software,a sapphire- dielectric resonator working at whispery gallery (WG) mode is developed.Cooperate with servo loop,an oscillator is constructed.In order to ensure high-Q factor,low temperature device based on digital PID control program is used to stablize temperature of the resonator within a range of 4.2 K to 15 K,with fluctuation below 1 mK.To further reduce phase noise,Pound circuitry is used to control phase of the oscillating frequency signal.When oscillating frequency is 9.2 GHz,single sideband (SSB) phase noise are measured.
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