张瑜,贺秋瑞.基于锁相环和混沌振子的微弱信号检测[J].电测与仪表,2012,49(7):37-40. ZHANG Yu , HE Qiu-rui.Weak Signal Detection Based on Phase Locked Loop and Chaotic Oscillator[J].Electrical Measurement & Instrumentation,2012,49(7):37-40.
基于锁相环和混沌振子的微弱信号检测
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.