正交四元探测器是第3代红外导引头的核心传感器，为了对该型导引头实施有效干扰，探讨了其探测工作机理，有针对性地提出影响其自动增益控制(AGC)电路工作的干扰策略，对干扰实施过程进行了仿真分析。采用蒙特卡洛方法模拟了在干扰存在频差，干扰占空比改变，干扰相位变化条件下的平均有效干扰率。仿真结果表明：以同频或倍频、0.25占空比、较高功率激光可影响导引头AGC电路正常工作，适时通过调整干扰相位可以影响干扰效果，最终破坏其信号提取逻辑，实现欺骗干扰。分析结果对于激光定向红外对抗系统的研制具有一定理论指导意义。

Quad-element detector is a key sensor of the third generation infrared seeker. In order to implement effective jamming to the seeker, this paper firstly discusses the detection mechanism,and secondly proposes the interference strategy which disturbs the auto gain control (AGC) circuit working.The jamming process is then simulated and analyzed.Finally,the average effective jamming ratio is acquired by Monte Carlo method when frequency difference exists,or duty cycle varies,or phase changes on jamming laser.The simulation conclusions are as follows:at the same or multiple frequency with the seeker and 0.25 duty cycle,high power jamming laser can lead the AGC circuit working abnormal;moreover,adjusting the pulse laser phase can influence the jamming effect and destroy the signal extraction logic,finally，the deception is achieved.The analysis and results of this paper are of theoretical significance for the development of laser directional infrared countermeasure system.