CAJ | 학술논문

HJ-1B卫星自发射以红外通道共进行了7次星上黑体定标，针对星上定标系数的验证工作开展较少，以MODIS第31、32通道为参考源，分别基于光谱响应差异和线性统计关系两种方法对HJ-1B红外通道星上定标系数进行验证。首先，计算两个传感器表观辐亮度的匹配关系，进而计算出HJ-1B红外通道的等效离表亮温，通过与HJ-1B红外通道基于星上定标系数反演得到的离表亮温进行比较，实现对星上定标系数的验证。通过半高宽法、矩方法和查找表法这三种不同的方法计算得到了2009年9月14日星上定标系数。结果表明：三种方法中，查找表法精度较高，且HJ-1B查找表法星上定标系数反演亮温与基于光谱响应差异和线性统计关系计算的等效亮温偏差较小，分别为0.02 K和0.81 K。这两种交叉验证方法的精度均在1 K以内，证明了该方法的可行性，且基于光谱响应差异的验证方法精度更高。该研究为光学载荷在轨辐射定标的验证提供了理论基础。
HJ-1B위성자발사이홍외통도공진행료7차성상흑체정표，침대성상정표계수적험증공작개전교소，이MODIS제31、32통도위삼고원，분별기우광보향응차이화선성통계관계량충방법대HJ-1B홍외통도성상정표계수진행험증。수선，계산량개전감기표관복량도적필배관계，진이계산출HJ-1B홍외통도적등효리표량온，통과여HJ-1B홍외통도기우성상정표계수반연득도적리표량온진행비교，실현대성상정표계수적험증。통과반고관법、구방법화사조표법저삼충불동적방법계산득도료2009년9월14일성상정표계수。결과표명：삼충방법중，사조표법정도교고，차HJ-1B사조표법성상정표계수반연량온여기우광보향응차이화선성통계관계계산적등효량온편차교소，분별위0.02 K화0.81 K。저량충교차험증방법적정도균재1 K이내，증명료해방법적가행성，차기우광보향응차이적험증방법정도경고。해연구위광학재하재궤복사정표적험증제공료이론기출。
Since HJ- 1B has been launched, 7 sets of blackbody data were used to calculate onboard calibration coefficients, but the research work on the validation of coefficients is rare. MODIS 31, 32 channels were selected as the reference sensor for the validation of the HJ- 1B infrared channel onboard calibration coefficients by using the methods of spectral response divergence and linear statistical relationship. Firstly, the relationship of top of atmosphere (TOA) radiance between the HJ- 1B thermal infrared channel and MODIS 31, 32 channels is calculated, and based on which the surface leaving brightness temperature is calculated to validate the brightness temperature calculated through the onboard calibration coefficients. According to the onboard calibration principle, calibration coefficients of HJ- 1B infrared channel on Sep 14th ,2009 are calculated with the Half﹣width, moments and look﹣up table methods. The results show that calibration coefficients calculated by the look﹣up table method has better precision. The difference between the brightness temperature of look﹣up table method and spectral response divergence and linear statistical relationship methods are within 1 K, 0.02 K and 0.81 K,respectively, which demonstrate the feasibility of both validation methods and the spectral response divergence method has high accuracy. The study may contribute to fundamental basis for the validation of in﹣flight calibration of optical payload.