FY-4A多通道扫描辐射成像仪评价与图像合成

风云四号卫星发射后,开展了卫星在轨评价工作.采用刃边法对太阳反射通道进行在轨MTF评价,结果表明,多通道扫描辐射成像仪各反射通道在轨MTF分别达到了0.14、0.17和0.22以上,符合仪器指标要求;利用面源黑体对红外通道噪声进行评价,结果表明多通道扫描辐射成像仪性能稳定,噪声大小只与辐冷温度有关,目标温度300 K时主要红外通道噪声优于0.2 K,最优通道达到了0.06 K;为准确检验红外定标精度,采用GSICS方法对红外通道业务定标结果进行检验,GSICS检验显示定标精度优于1 K,最优通道达到了0.3 K@290 K.为充分发挥多通道扫描辐射成像仪多通道联合应用效能,根据多通道扫描辐射成像仪反射通道的响应特点,在没有符合人眼红绿蓝响应通道的情况下,提出了新的真彩色图像合成方法,生成了符合人眼效果的真彩色明显.

On-orbit test to FY-4A AGRI and generating RBG image

After launching Feng Yun-4 ( FY-4) , the on-orbit test to the satellite is done, the M TF of the solar reflectance bands is better than 0. 14, 0. 17 and 0. 22, that is better than the designed capability.The noise test is based on the black-body on the apparatus, the noise for all the infrared bands is less than 0. 2 K @ 300 K, the noise of the best band is about 0. 06 K @ 300 K. The calibration precession of infrared band is validated by the GSICS algorithm, the bias of all the infrared bands are less than 1 K comparing to IASI, the bias of the best band is about 0. 3 K @ 290 K. The RGB image carries more information than the gray image, although the AGRI has 6 solar reflectance bands, there are no real red, green and blue bands of human beings, a new algorithm generating RGB image for AGRI is suggested, based on the character of 0. 82 band, a very beautiful RGB image w hich is good to human beings is generated, that improves the multi band use for AGRI.