红外图像导引头的视场、作用距离及识别概率是评价该系统性能的重要指标。文中提出大小视场切换的概念,用大视场捕获区域大和小视场识别概率高的特点解决了视场与作用距离的矛盾,通过Johnson判别准则论证不同视场下的作用距离和探测识别概率。利用大小视场切换概念设计的导引头通过了外场试验验证,该方法能够为系统设计与性能评估提供参考。

The infrared imaging seeker field of view, effect distance and identify probability are important index for evaluating the system. In this paper, the concept of switching between wide and narrow field of view was proposed, and the problem between field of view and effect distance was solved by using characteristic featured with larger engage area in wide field of view and higher identify probability in narrow field of view. The effect distance and identify probability in wide and narrow field of view were estimated by Johnson criterion. The seeker designed with the concept of switching between wide and narrow field of view was validated by aviation test, and this way can be referred for system design and performance evaluation.