锁相电路是相位锁定环(Phase Locked Loop)的简称，主要由鉴相器、环路滤波、压控振荡器成 。主要是要掌握LabVIEW图形化编程特点，-PLL circuit is phase-locked loop (Phase Locked Loop) for short, mainly by the phase detector, loop filter, VCO into. Mainly to grasp the features of LabVIEW graphical programm