射频锁相环电路工作特性仿真与分析

射频锁相环是一种能够跟踪输入信号相位变化的闭环自动跟踪系统,此类电路具有负反馈闭环特点、系统状态多,工作特性复杂,其故障诊断和定位是无线电设备维修保障中的难点问题。针对上述问题,研究了射频锁相环电路的工作特性与故障定位方法。首先,针对典型射频锁相环电路,推导得到了其数学模型。然后,建立了其电路仿真的模型,仿真分析了环路四种主要工作状态和各模块对环路整体性能的影响。最后,采用开环故障隔离与关键节点信号比对法进行环路故障定位。研究结果为模拟锁相环电路故障诊断提供了理论依据,对实际电路故障诊断具有一定参考价值。

Simulation and Performance Analysis of Radio Frequency Phase Locked Loop Circuit

RF PLL is a closed-loop automatic tracking system which can track the phase change of input signal.This kind of circuit has the characteristics of negative feedback closed-loop,multi-state and complex working characteristics.Its fault diagnosis and location is a difficult problem in the maintenance and support of radio equipment.In view of the above problems,the working characteristics and fault location methods of RF PLL circuit were studied in this paper.First,the mathematical model of a typical RF PLL circuit was derived.Then,the circuit simulation model was established,and the influence of each module on the loop performance was analyzed.Finally,the open loop fault isolation and key node signal comparison method were used for loop fault location.This paper provides a theoretical basis for fault diagnosis of analog PLL circuit,and has a certain reference value for practical circuit fault diagnosis.