摘要
基于时间延迟积分的红外点目标探测系统在推扫成像过程中会受到速度失配的影响导致点目标的探测性能降低.基于调制传递函数的传统频域建模分析方法由于缺少相位传递函数的介入,无法对目标探测性能的影响进行有效分析.为了解决该问题,采用成像系统的点扩散函数以及线扩展函数建立了成像系统的速度失配模型,并对速度失配对目标检测系统的影响进行了研究.模型理论计算以及实际成像实验结果表明,当时间延迟积分级数为8级,速度失配量ΔV/V=25%时,点目标能量响应均值下降50%,当速度失配达到ΔV/V=12.5%时,点目标能量响应均值下降30%.研究结果可为后续红外时间延迟积分成像系统的设计提供参考.
The velocity mismatch would be inevitably in the push-broom imaging process based on time delay integration,which leading to a decrease in detection performance of point targets.Due to the lack of introduction of phase transfer function,the influence of the target detection performance can not be effectively analyzed by the frequency domain methods based on modulation transfer function.In order to solve this problem,the relationship between detection performance of point targets and velocity mismatch was studied with the establishment of the mathematical model by the point spread function and line spread function of the imaging system.The result of theoretical calculation and imaging experiment shows that the expectation of point target response will drop by approximately 50% by 8-stage time delay integration,when the velocity mismatch ratioΔV/V=25%.When the velocity mismatch ratioΔV/V=12.5%,the expectation of point target response decrease 30%.This research could provide reference for infrared time delay integration imaging system design.
引文
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