海面环境中红外偏振成像系统作用距离模型

诸多实验证明海面辐射具有偏振特性,目前还没有有效的红外偏振成像系统的海面目标探测能力的相关理论。利用T. Elfouhaily提出的海浪方向谱模型反演出海浪高度分布;通过一种基于Monte-Carlo光线逆追踪的方法分析了海面的红外偏振辐射特性;根据Stokes矢量分量的噪声特性建立了Stokes矢量各分量的最小可分辨温差值(MRTD)计算方法;并在此基础上,利用Stokes矢量分量的MRTD与场景的表观温差(ATD)的差异建立了海面环境中的红外偏振成像系统作用距离模型。

Distance model of infrared polarization imaging system used in sea-surface environment

The fact that infrared radiation of sea surface is polarized has been proved by many experiments. Searching and detecting ability of infrared polarization imaging systems in sea-surface environment was a major concern for polarization imaging research. Sea surface was realized by using a statistical model of oceanographic literature which originated from the spectrum for long and short wind-driven waves proposed by Eifouhaily. A Monte Carlo reverse ray-tracing method was used to investigate the behavior of mid/long-wave infrared Stokes radiance which included the information of radiance intensity, degree of polarization and angle of polarization, at the realized wind roughed sea surface. The minimum resolvable temperature difference(MRTD) parameters for Stokes-vector components were proposed based on standard error propagation method. Finally, detectable range of infrared polarization imaging used in sea surface environment was analyzed by comparing apparent-temperature differences(ATD) between target and sea background with the MRTD of Stokes-vector components.