嵩山遥感定标场靶标反射率的自动测量方法

利用自主研制的地表反射自动监测光谱仪 (ARMS) 和可见-短波红外光谱辐照度计 (HIM)， 实现了嵩山遥感 定标场内三种灰阶靶标反射率的自动测量， 并与使用ASD便携式光谱仪人工测量的靶标反射率开展了比对。两种方 法的比对结果表明： 在400～1600 nm范围内， 自动化测量与人工测量的反射率数据在非大气吸收波段的相对偏差优 于 ±2%。进一步基于自动化设备的观测数据， 分析了2019 年10 月至2020 年11 月场地内的靶标反射率。分析结果表 明， 受环境变化的影响， 嵩山场内灰阶靶标的反射率也会发生变化， 且反射率的变化趋势与波长范围及测量区域有 关。在整个波段范围内， 反射率的标准偏差在 ±2.5%以内。该工作的开展为基于嵩山遥感定标场的自动化、高频次在 轨辐射定标提供了有力的技术支撑。

Automatic measurement method of target reflectivity at Songshan Remote Sensing Calibration Field

Based on the self-developed automated reflectance monitoring spectrometer (ARMS) and hyperspectral irradiance meter (HIM) in visible-shortwave infrared band, the automatic measurement of the reflectance of three gray-scale targets in Songshan Remote Sensing Calibration Field, China, was realized, and the data obtained by the self-developed instruments was compared with the data acquired manually by the ASD portable spectrometer. The comparison results of the two methods show that the relative deviation of the reflectance data is better than ±2% in the range of 400-1600 nm for nonatmospheric absorption band. Then the target reflectance data in the site acquired by the automated equipments from October 2019 to November 2020 was analyzed in details. The analysis results show that the target reflectance of Songshan field is changeable with the environment, and the change trend of reflectance is related to the wavelength range and the measurement area, while the standard deviation of reflectance is within ±2.5% in the whole band. The work provides a strong technical support for the automatic and high-frequency on-orbit radiation calibration based on the Songshan Remote Sensing Calibration Field.