The Design And Research Of 4GHz DRO With Low Phase Noise

Dielectric Resonator Oscillator (DRO) with high stability,low phase noise,good spectrum purity and many other advantages,is widely applied in microwave oscillator.Therefore,the indepth research and analysis can give rise to some guiding significance for engineering application.A 4GHz DRO with low phase noise is designed by using the package circuit model of the bipolar transistor AT-42035 and the impact of various parameters on the circuit is studied in ADS and the 4GHz DRO designed is manufactrued and measured in this thesis.The main contents in this thesis is carried out as follows:(1) The dielectric resonator and microstrip line coupled model is established by using CST software and the impact of various parameters on the resonant characteristics of the resonant circuit is also studied.(2) The negative resistance circuit part of DRO is designed by using the package equivalent circuit model of the bipolar transistor AT-42035 and the impact of various parameters on the circuit negative resistance characteristics is studied.(3) The resonant network part of DRO is designed and researched by using the dielectric resonator model and CST model in ADS respectively.(4) A feedback type DRO is designed and the phase noise characteristics,frequency stability characteristics and output power characteristics about DRO are analyzed in this thesis.(5) A 4GHz DRO is manufactured,debugged and measured.The debugging methods are summarized and the measured results are also compared with the simulated results.Finally,the 4GHz DRO with low phase noise is implemented and the phase noise is showed as follows:-106.51dBc/Hz@10kHz,-123.86dBc/Hz@100kHz,-148.0dBc/Hz@1MHz.Based on the measurement data,some improvements on the deficiencies are proposed.