一种微弱光电信号调制解调电路设计研究

本文针对微弱光电信号或弱信噪比条件下的光电信号检测及数据采集,设计了一种基于自相关检测原理的调制解调电路,旨在用于传感器的光电强度调节及低信噪比信号检测.该电路利用自相关特性较明显的伪随机码与光纤传感器对被检测微弱信号进行调制解调,通过检测输出光强度达到检测微弱信号的目的.同时,对该电路方案进行了强噪声条件下的检测性能仿真研究,仿真结果表明,该电路方案能够有效地实现弱信噪比条件下的光电信号检测及数据采集.

Design of modulation/demodulation circuit based on the weak photoelectric signal

In allusion to the photoelectric signal detection or data acquisition under the condition of the weak photoelectric signal or weak signal to noise ratio, the modulation/demodulation circuit based on the autocorrelation detection principle is proposed. It is aimed at the photoelectric intensity adjustment of the modulation sensor and the detection of weak signal.The circuit uses pseudo random code and optical fibre sensor to modulate the weak signal and detects the weak signal according to the output light intensity. Meanwhile, the numerical simulation for the sensing circuit with strong noise is carried out. According to the simulation results, photoelectric signal detection and data acquisition based on the weak signal to noise ratio conditions are realized effectively.