宽动态范围红外辐射测量系统快速定标算法

High-speed calibration algorithm for wide dynamic range infrared radiometric system

红外辐射测量系统的宽动态范围定标通常是在多个温度点下,设置多个积分时间并适当加入衰减片的方式实现的。其不仅效率低、耗时长、成本高且影响整个红外辐射测量系统实时性和机动性。对此,在考虑积分时间的定标模型基础上,提出宽动态范围快速定标方法。只需调节一次积分时间和一次温度即得到宽动态范围任意积分时间的定标方程。利用Φ400 mm红外辐射测量系统对快速定标方法的定标精度、测量精度进行验证。实验结果表明:快速定标方法与直接定标结果之间最大误差为2.75%,该方法外场测量时最大辐射测量误差为11.69%,相比传统辐射测量最大误差不超过1.52%。说明快速定标方法能有效地保证系统辐射定标精度,提高辐射测量系统的定标效率,缩短定标时间,实现对系统宽动态范围任意积分时间的定标。整个辐射测量过程实时性好,操作简单、易实现且可靠性高,适应针对外场条件下红外辐射特性测量系统的要求,外场测量结果也说明快速定标可以直接应用于靶场目标的红外辐射测量任务中。

Several different integral times at multiple temperatures added by the attenuators are often required for the wide dynamic range infrared radiometric systems. It＇s not only inefficient, time- consuming and costly, but also affects real-time and mobility when used for the missions. Based on the calibration model considered integral time, the high-speed calibration algorithm was proposed for wide dynamic range and random integral time. The algorithm can obtain calibration equation for wide dynamic range and random integral time mainly by only turning one temperature point and one integral time point. The verifying experiments were performed by the Φ400 mm infrared radiometric systems, for purpose of the accuracy of calibrations and measurements by the algorithm mentioned above. Experimental resultsshow that the high-speed calibration algorithm compared with the direct calibration results maximum error is 2.75%, the maximum error radiant measurement is 11.69% and the maximum error compared to the conventional radiant measurement result is not more than 1.52%. The high-speed calibration algorithm can improve the efficiency of radiometric calibration, shorten the calibration time and achieve the equation of calibration at random time on the premise of the accuracy of consequences. The entire process of mission is real-time, simple operation, high reliability, easy to implement and suitable for the measurement requirements to infrared radiometric system, that can be directly applied to the target range of infrared radiometric missions.