微弱信号检测的锁相放大电路仿真

Simulation of phase locked amplifier circuit for weak signal detection

在实际传感器检测领域中,微弱信号通常被噪声信号所淹没,为有效的获取微弱信号本身并将其放大测量,设计了一种微弱信号检测的电路,利用互相关原理将微弱信号提取,同时去除噪声的干扰,该微弱信号检测电路可在大量非相关噪声中检测出频率已知的确定信号,经Multisim仿真表明,系统在无噪声信号输入时,完成了线性度较完好的,且测试精度小于4.2%的微弱信号检测电路。

In the field of actual sensor detection,weak signals are usually submerged by noise signals.In order to effectively obtain weak signals themselves and amplify them for measurement,a weak signal detection circuit is designed.The weak signals are extracted by using the principle of cross-correlation,and noise interference is removed.The weak signal detection circuit can detect the determined signals with known frequencies in a large number of non-correlated noises.The Multisim simulation shows that when no noise signal is input,the system completes a weak signal detection circuit with good linearity and less than 4.2%test accuracy.