摘要
非均匀性是影响红外遥感系统探测灵敏度的重要因素之一。随着红外遥感系统探测性能的提升,探测幅宽越大、辐射分辨率越高,对非均匀性要求也越高,而传统的非均匀性校正技术残差较大,难以满足要求,非均匀性已经成为限制红外系统在各领域深入应用的严重问题。针对高灵敏度长线阵推扫型海洋红外遥感系统,提出一种采用90°旋转定标(side-slither)和基于场景相结合的自适应校正技术。首先根据海洋背景红外辐射特性模型和系统响应特性,完成红外图像的仿真;通过side-slither定标技术,实现对图像的预校正以及盲元替换;根据side-slither原理,分析链路中影响校正残差的各因素,主要包括平台偏航和场景的高频动态变化,导致所有像元不能对同一辐射强度的场景成像,增大校正后图像的非均匀性残差。为进一步抑制非均匀性残差,对图像进行基于场景的自适应校正,仿真结果表明,经side-slither定标和恒定统计场景校正后,图像非均匀性残差能接近或小于时间噪声水平,满足高灵敏度探测需求,能够为后续红外弱目标的检出提供高品质图像。
Nonuniformity is one of the important factors influencing detection sensitivity. Following the performance promotion of infrared systems, nonuniformity became one of important factors influencing detection sensitivity. Higher sensitive system with larger swath width needs stricter requirements of NUC （Nonuniformity Corrected Technology, NUC）. For ocean push-broom infrared sensors, an NUC conjuncting side-slither and scened-based self-adaptive NUC method is proposed. Firstly, according to SNR models, infrared images with target and noise signals are simulated. By side-slither NUC, coarse correction is realized. Influence factors of side-slither NUC include platform yawing and scene dynamic changes with high frequency, which results in that all pixels can＇t image the same object and the residual nonunformity become higher. Secondly, scened-based NUC is introduced. Simulation results demonstrate that the residual space noise could be close to temporal noise and satisfy our needs of detection sensitivity.
作者
张丽莎
刘兆军
马文坡
龙亮
吴立民
阮宁娟
钱惟贤
ZHANGLisha LIUZhaojun MAWenpo LONGLiang WULimin RUANNingjuan QIANWeixian(Beijing Institute of Space Mechanics ＆ Electricity, Beijing 100094, China Nanjing Univereity of Science and Technology, Nanjing 210094, China)
出处
《航天返回与遥感》
CSCD
北大核心
2017年第1期78-87,共10页
Spacecraft Recovery & Remote Sensing
