通过构建适用于HJ-1B 热红外通道(IRSB08)特性的有效波段宽度计算方法, 提高HJ-1B B08 在轨星上绝 对辐射定标的精度。根据HJ-1B 星上定标原理、利用卫星发射前地面实验数据和Planck 方程, 建立基于定标黑体 温度的有效波段宽度计算的查找表法, 结果表明查找表法得到的有效波段宽度为2.01 ?m 左右, 介于半高宽法 1.940 ?m 和矩方法2.394 ?m 之间, 且与定标黑体温度的关联性很小, 在低温点和高温点之间的相对差异在0.3%以 内。半高宽法和矩方法分别低估和高估有效波段宽度, 导致定标后的表观辐射亮度分别偏高和偏低, 不适用于 HJ-1B B08 特点, 查找表法定标的表观辐亮度与星地同步实验结果非常相近, 绝对误差为0.04 W·m?2·sr?1·?m?1, 对 应的亮度温度误差为0.4 K 左右, 能很好的应用于HJ-1B B08 在轨星上绝对辐射定标。

Improve HJ-1B B08 on-board absolutely radiometric calibration precision by virtue of a constructed lookup table (LUT) method that fit for HJ-1B B08 characteristic to calculate its effective bandwidth. LUT method is based on HJ-1B on-board radiometric calibration theory, pre-launched experiment datum and Planck formula. As a result, HJ-1B B08 effective bandwidths are 2.01m, 1.940 m and 2.394m corresponding to LUT method, FWHM method and moments method (MM). LUT method has low association to blackbody temperature, and the relative difference is 0.3% between normal temperature and high temperature state. FWHM method and MM method are either higher or lower, and the calibrated top of atmospheric(TOA) radiance is either lower or higher, so they are not fit for HJ-1B B08 characteristic. LUT method gives a result that very close to field experiment, and the absolutely error is 0.04 W·m 2·sr?1·m 1corresponding to approximately 0.4 K TOA radiant temperature error, so it can be better when used to HJ-1B B08 on-board absolutely radiometric calibration.