基于锁相环和混沌振子的微弱信号检测

为精确检测纳伏级微弱正弦信号的频率和幅值,构建了基于锁相环和Duffing振子的微弱信号混合检测系统。首先通过锁定输入锁相环的待测信号,完成信号频率的检测;然后利用锁相环输出的已知频率信号作为混沌系统的内置策动力信号,将输入到混沌系统的待测信号用Duffing振子进行幅值检测。仿真结果表明,混合系统可同时完成纳伏级微弱正弦信号的频率和幅值的检测,检测信号的最低信噪比为-22.23dB,且操作简单,工作量小,易于实现。

Weak Signal Detection Based on Phase Locked Loop and Chaotic Oscillator

In order to detect accurately the amplitude and frequency of a nV-level sine signal,a hybrid detection system of weak signal based on phase locked loop and chaotic oscillator was built.First,by locking the measured signal which is input to phase locked loop,the signal frequency detection is completed.Then,taking the phase locked loop output signal whose frequency is known as the internal motive power signal of the chaos system,the amplitude of the input measured signal to the chaos system can be detected by Duffing oscillator.Simulation results show that: the hybrid system can detect the frequency and the amplitude of a nv-level weak signal at the same time;the lowest SNR of the signal is-22.23dB,and the hybrid system is easy to operate,which needs small amount of work and is easy to realize.