针对Ka和Ku波段上、下变频装置对微波振荡器低相位噪声和小型化的要求,该文采用单环锁相式频率合成技术完成了微波振荡器的设计,并对锁相环的相位噪声进行了理论计算。分析了鉴相频率、鉴相器灵敏度和环路带宽对锁相环输出相位噪声的影响,根据分析结果对微波振荡器电路参数合理选择,同时兼顾了低相位噪声与小型化的设计要求。测试结果表明,振荡器的相位噪声指标与理论计算一致,各项指标均达到要求,可满足实际工程应用。
Aiming at the miniaturization and low phase noise requirements of microwave oscillator to the up and down frequency conversion devices operating at Ka and Ku band,using the single phase locked loop (PLL) frequency synthesizer technology, the microwave oscillator is designed and the PLL phase noise is calculated.The effect of the phase detector frequency,the phase detector sensitivity and the loop bandwidth on the output phase noise of the phase locked loop are analyzed.According to the analysis results,the microwave oscillator circuit parameters have been reasonably chosen and both low phase noise and small size have been taken into account.The test results show that the calculation and measurement of phase noise indexes agreed well and can meet the practical engineering application.