【摘要】 在使用π网络零相位法对高频石英晶体进行测试时,相位检测技术是关键。本文所设计的鉴相系统采用混频技术,降低所要鉴相的频率,对固定频率进行相位检测。经实验验证,本测试系统的测试频率范围1MHz~200MHz,相位检测的精度能够满足串联谐振频率的测试精度±2ppm的要求,重复精度大于0.5ppm。更多还原

【Abstract】 The technique of phase detector is important in measuring the high frequency quartz crystal resonant frequency by zero phase technique in a π- network . On the basis of research, the measuring experiment system is designed which uses mixer to fall down the frequency which will be detected , then measures the phase error of the two signals which have the same frequency . From the result of the experiment, the measuring frequency range of this method is 1MHz~200MHz; the measuring accuracy of series resonant frequency is ± 2ppm.Repeated measuring experiments, the result shows that the maximum standard difference is 0.5ppm.更多还原