亚毫米波冰云成像仪通道选择

Channel selection of sub-millimeter ice-cloud sounder

依据冰云参数的多极化多散射大气亚毫米波辐射传输模型,分析了100 GHz^1 000 GHz频段内大气卷云吸收的特性,通过通道频率和带宽的不同设置,确定亚毫米波冰云成像探测仪包含15个通道,频率覆盖范围为118 GHz^900 GHz,建立其与遥感器通道灵敏度、定标精确度、不同地理位置和海拔高度上对流层卷云中冰水总量、冰晶粒子尺寸、形状、方向性等反演参数的约束模型,为设计和研制用于测量冰云参数的星载亚毫米波成像仪提供理论分析和仿真验证。

Based on the characteristics of multi-polar and multi-scattering for ice-cloud, the appropriate sub-millimeter atmospheric radiative transfer model is used to analyze the absorption and scattering of atmosphere from 100 GHz-1 000 GHz. The relationship between the sensitivity/calibration accuracy and channel specifications of sub-millimeter ice-cloud imager is analyzed, such as frequency, bandwidth, dual-band and polarization type settings, and then a 15-channel ice cloud imager which covers the frequencies from 118 GHz-900 GHz is proposed. The limitations of the parameter retrievals' accuracy of ice-clouds distributed in different regions and at different heights in the troposphere are considered, because different geographic locations and altitudes can result in a significantly difference for total ice, ice particle size, shape and direction of ice-clouds. Finally, the specific indicators which will play a vital part in designing the sub-millimeter ice-imager onboard Chinese satellite are proposed.