为了处理二阶系统模型参数的大范围不确定性，提出了基于跟踪微分器的模型参考自适应控制，利用两个非线性跟踪微分器分别得到系统输出的微分信号和误差的微分信号，同时抑制了高频噪声放大效应。根据被控对象的数学模型，自适应调节律能自动实时调节控制律中的参数。实验结果表明,当雷达伺服系统被控对象模型的参数在较大范围内变化时，该新型控制器有效补偿了二阶系统参数的不确定性，提高了伺服系统稳态和动态跟踪精度，保证了系统的全局渐近稳定。

The model reference adaptive control based on tracking differentiators is proposed to deal with the parameters large-scale uncertainty of second-order systems model.It adopts two tracking differentiators to obtain respectively the differential signals of the system output and error，which can reject the high-frequency noise amplification effect.According to the mathematical model of the controlled plant，an adaptive regulator law can automatically adjust parameters of a control law.The experiments results show that the new controller can effectively compensate the parameters uncertainty of the second-order system when the controlled plant parameters of the radar servo system vary in large range and increase the steady and dynamic precision of the servo system.Thus can guarantee the global asymptotic stability of the system.