采用四象限探测器的激光跟踪系统设计

为简化自由空间激光通信的跟踪系统,本文采用四象限探测器检测目标位置,通过峰值保持电路稳定激光脉冲峰值并计算脱靶量,结合角速率和角位置信息,采用基于位置环、速率环、电流环的闭环控制算法实现视轴稳定与目标跟踪。仿真设定载体扰动频率为3 Hz时,系统的隔离度达到1.0%；目标位置±20°正弦变化时,能稳定跟踪；脱靶量噪声是跟踪误差的主要因素,峰值信噪比20 dB时,跟踪误差0.07°。结果证明系统设计可行,为激光跟踪样机研制奠定了基础。

Design of laser tracking system with quadrant detector

In order to simplify the tracking system of free space laser communication,a quadrant detector was used to detect the target position in tracking system. Peak hold circuit was designed to maintain the peak voltage of laser pulse and calculate miss angle. According to angle velocity and angle position information,Control algorithm based on position loop,velocity loop and current loop was used to realize optical axis stabilization and target tracking. The isolation is 1.0% when the set perturbing frequency is 3Hz in simulation. And the system can track the target stably when target position varies sinusoidally from -20° to 20° . Noise of miss angle is the main factor of tracking error. When the signal to noise ratio of peak is 20 dB,tracking error is 0.07°. The results prove that the system design is feasible,which provides a good foundation for the development of laser tracking prototype.