中文摘要：

风云三号C星（FY-3C）已经于2013年9月23日发射升空,其上装载的微波湿温探测仪（MWHTS）已于9月30日开机正常工作.MWHTS具有对大气温度和湿度垂直分布进行同步探测的能力.MWHTS为跨轨扫描式微波辐射计,在89-191GHz毫米波段内设置了十五个探测通道,其中包括118.75GHz氧气吸收线附近的8个大气温度探测通道,183.31GHz水汽吸收线附近的5个大气湿度探测通道,以及89GHz和150GHz两个窗区通道.设置在118.75GHz的一组毫米波探测通道是国际上业务卫星首次使用的大气探测通道,这组通道和183.31GHz通道对大气进行联合探测,将获得更加精细的大气温湿度垂直分布数据,为数值预报和气候研究提供丰富信息.为保证MWHTS观测资料的定量应用,对仪器性能和定标精度进行了在轨测试.利用MWHTS在轨正常工作后的三个月数据,对仪器在轨定标的基础数据：冷空和黑体计数值,黑体和仪器温度进行监测分析和质量检验,经过质量检验的在轨定标基础数据,结合发射前真空试验得到的非线性订正项在轨定标生成MWHTS观测亮温数据.评估MWHTS在轨辐射定标结果的精度和偏差特性使用了三种方法：1通过场地定标试验获取大气温湿廓线和地面温度等大气参数信息,结合微波逐线正演辐射传输模式MonoRTM（Monochromatic Radiative Transfer Model）模拟MWHTS的上行微波辐射亮温,与MWHTS实际观测结果进行对比分析;2两个通道特性一致的同类星载被动微波载荷同时观测同一目标,观测亮温的差异主要取决于两个载荷的定标系统偏差.选取美国SNPP上搭载的微波探测仪器ATMS作为MWHTS的参考载荷,基于SNO（simultaneous nadir overpass）技术,对两个仪器的观测亮温进行交叉比对,观测亮温时空匹配及均匀性检验的条件为：观测时间差异小于20min,观测像元中心距离小于3km,观测角度在星下点附近差异小于5°,观测像元周围3×3像元内的亮

英文摘要：

The Fengyun（FY）-3Csatellites was successfully launched on 23 December 2013and carries the Microwave humidity and temperature sounder on board which started its measurements since December 30.MWHTS observe the vertical distribution of atmospheric temperature and moisture.MWHTS is a cross-track scanning instrument which observing in 15 channels at frequencies ranging from 89 to 191GHz.Eight temperature sounding channels have center frequency at 118.75 GHz oxygen absorption line,five humidity sounding channels have center frequency at 183.31 GHz water vapor absorption line and two window channels centered at89 and 150 GHz.118 GHz channel is first used to detect atmosphere on current operational satellite.118 GHz and 183 GHz channels can obtain fine vertical distribution structure of atmosphere humidity and temperatures.These data will be used in data assimilation and climate research.Before MWHTS observationsquantitative application,the on-orbit test was carried out.The MWHTS post-launch instrument performance was conducted with on-orbit data during a period of three months.The main parameters monitored include the radiometric counts from the cold space and warm target,the warm target temperature and instrument temperature.These calibration data through quality control were converted to brightness temperature use non-linear correction and correction of antenna spill-over effects.There are three methods to validate MWHTS measurements：1.Use the atmospheric humidity and temperature profiles and surface temperatures which were observed by site calibration test in the radiance transfer model Mono RTM（Monochromatic Radiative Transfer Model）to simulating the MWHTS radiation.The difference between simulations and measurements are assessed.2.When the same kind sensors observe the same target at the same time,the observed brightness temperature difference should be the small and constant bias.The ATMS on a SNPP satellite was used to be reference sensor.The MWHTS calibration results are cross compared with ATMS by th