Analysis and Example of Operating Range Calculation Method for Point Target in Infrared System
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摘要: 红外系统的作用距离参数是表征红外系统成像性能的重要指标。目前,红外系统作用距离的计算方法有多种,但都有其各自的适用性和局限性,因此需要考虑不同条件下多种因素对作用距离的影响。本文基于探测能量、基于噪声等效温差(NETD)的和基于对比度的3种点目标探测的作用距离模型,发现在不同条件下应用的局限性。当观测目标为人时,基于NETD的模型计算作用距离为8.74 km,与外场实验数据更为接近。而当观测目标为飞机时,基于能量的模型计算作用距离为32.04 km,与外场实验数据更为接近。结果表明,针对不同特征的目标,选取适当的作用距离计算方法有助于提高系统作用距离估算的准确度。Abstract: The operating range parameter of an infrared system is an important index for characterizing its imaging performance. At present, there are many methods to calculate the operating distance of infrared systems, but they all have their own applicability and limitations. It is necessary to consider the influence of various factors on the operating distance under different conditions. In this study, based on the detection energy, noise equivalent temperature difference (NETD), and contrast, we found limitations under different conditions. When the observation target was a human, the calculated operating distance based on the NETD model was 8.74 km, which is closer to field experimental data. When the observation target was an aircraft, the calculated operating distance based on the energy model was 32.04 km, which is also closer to field experimental data. These results show that, according to the different characteristics of the target, selecting the appropriate calculation method for the operating distance is helpful in improving the accuracy of the system operating distance estimation.
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Key words:
- infrared system /
- operating range /
- point target /
- NETD /
- contrast
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表 1 目标作用距离计算结果
Table 1. Target action distance calculation results
Target Human beings Aircraft Emissivity 0.98 0.6 Temperature/K 296 800 Experimental data of typical target in outfield/km 5.6 27.7 Action distance algorithm based on energy/km 10.63 32.04 Distance algorithm based on NETD/km 8.74 38.45 Action distance algorithm based on contrast/km 12.04 46.82 -
[1] 王永仲. 现代军用光学技术[M]. 北京: 科学出版社, 2003.WANG Yongzhong. Modern Military Optical Technology[M]. Beijing: Science Press, 2003. [2] 杨宜禾, 岳敏, 周维真. 红外系统[M]. 北京: 国防工业出版社, 1995.YANG Yihe, YUE Min, ZHOU Weizhen. Infrared System[M]. Beijing: National Defense Industry Press, 1995. [3] 哈得逊 R D. 红外系统原理[M]. 北京: 国防工业出版社, 1975.Hudson R D. Principles of Infrared Systems[M]. Beijing: National Defense Industry Press, 1975. [4] 郭晓东. 红外点目标探测系统的作用距离理论模型分析[J]. 红外, 2019, 40(7): 18-25. doi: 10.3969/j.issn.1672-8785.2019.07.003GUO Xiaodong. Theoretical model analysis of operating range of infrared point target detection system[J]. Infrared, 2019, 40(7): 18-25. doi: 10.3969/j.issn.1672-8785.2019.07.003 [5] 罗振莹, 白璐, 宁辉, 等. 基于NETD的红外探测系统作用距离分析[J]. 红外, 2017, 38(5): 27-30. doi: 10.3969/j.issn.1672-8785.2017.05.005LUO Zhenying, BAI Lu, NING Hui, et al. Distance analysis of infrared detection system based on NETD[J]. Infrared, 2017, 38(5): 27-30 doi: 10.3969/j.issn.1672-8785.2017.05.005 [6] 李希希, 张葆, 洪永丰. 红外系统对点源目标的作用距离估算模型[J]. 电光与控制, 2016, 23(3): 16-18. https://www.cnki.com.cn/Article/CJFDTOTAL-DGKQ201603005.htmLI Xixi, ZHANG Bao, HONG Yongfeng. Effect distance estimation model of infrared system on point source target[J]. Electro-optics and Control, 2016, 23(3): 16-18. https://www.cnki.com.cn/Article/CJFDTOTAL-DGKQ201603005.htm [7] 苏䶮, 王前学, 周海渊, 等. 中波红外系统探测能力计算方法[J]. 价值工程, 2018, 37(25): 177-180. https://www.cnki.com.cn/Article/CJFDTOTAL-JZGC201825083.htmSU Yan, WANG Qianxue, ZHOU Haiyuan, et al. Calculation method for detection capability of medium wave infrared system[J]. Value Engineering, 2018, 37(25): 177-180. https://www.cnki.com.cn/Article/CJFDTOTAL-JZGC201825083.htm [8] 孙明昭, 田超, 王佳笑. 不同大气条件下红外成像系统作用距离评估[J]. 激光与红外, 2017, 47(3): 304-307. doi: 10.3969/j.issn.1001-5078.2017.03.009SUN Mingzhao, TIAN Chao, WANG Jiaxiao. Evaluation of operating distance of infrared imaging system under different atmospheric conditions [J]. Laser and Infrared, 2017, 47(3): 304-307 doi: 10.3969/j.issn.1001-5078.2017.03.009 [9] 巢时宇, 李桂祥, 李志淮, 等. 红外系统距离方程与作用距离分析[J]. 空军雷达学院学报, 2011, 25(5): 318-321. https://www.cnki.com.cn/Article/CJFDTOTAL-KLDX201105003.htmCHAO Shiyu, LI Guixiang, LI Zhihuai, et al. Distance equation and action distance analysis of infrared system [J]. Journal of Air Force Radar College, 2011, 25(5): 318-321. https://www.cnki.com.cn/Article/CJFDTOTAL-KLDX201105003.htm