针对星载云雷达对冰云探测可行性分析的需求，分析了非球形冰晶对340 GHz电磁波的单散射特性，基于不同的体积散射模型，研究了非球形冰晶云的回波特性以及94\340 GHz云雷达双波长比，假定冰云垂直分布的情况下，探讨了星载94\340 GHz云雷达双波长比随高度的变化以及可以穿透的冰云厚度。相较于94 GHz及220 GHz，冰晶粒子对340 GHz电磁波的散射能力增强，但是同时云对其的衰减也大大增加，340 GHz的衰减系数约是94 GHz的5～130倍；340 GHz云雷达可以探测浅薄的含水量较小的冰云，基本可以探测云厚2 km、冰水含量在 0.000 1~0.2 g/m³的冰云。含水量较多的厚云由于衰减，造成电磁波穿透能力大大降低，在假定的冰水含量垂直分布下，当最大冰水含量为1 g/m³时，可探测厚约5 km内云厚的40%以上；衰减也造成不同高度上相同滴谱的云有不同的双波长比，冰水含量的大小及垂直分布影响了双波长比的大小及电磁波探测云的厚度。衰减随着冰水含量增大而增大，高频云雷达电磁波衰减大，使得双波长比变大，从而使双波长比和谱的数浓度N₀有关，因此利用双波长比反演时，衰减订正非常重要。

Aiming at the requirement of feasibility analysis for ice cloud detection by space borne cloud radar， the single scattering characteristics of non-spherical ice crystals to 340 GHz electromagnetic wave were analyzed， then the echo characteristics of non-spherical ice crystal cloud and dual wavelength ratio （DWR） of 94\340 GHz cloud radars were studied based on different volume scattering models， while the variation of DWR with altitude and the thickness of ice clouds that can be penetrated were discussed assuming the vertical distribution of ice clouds. Compared with 94 GHz and 220 GHz， the scattering ability of ice particles to 340 GHz electromagnetic wave is enhanced， but at the same time， the attenuation by clouds is also greatly increased， and the attenuation coefficient of ice clouds to 340 GHz wave is about 5~130 times that to 94 GHz wave. The 340 GHz cloud radar can detect the shallow ice clouds with low ice water content （IWC）， that is， ice cloud with thickness of 2 km and IWC of 0.000 1～0.2 g/m³ can be detected basically， and the electromagnetic wave penetration ability is greatly reduced due to the attenuation of thick clouds with more water content， when the maximum IWC reaches 1 g/m³ in the condition of the assumed vertical distribution of IWC， about more than 40% of cloud thickness for ice clouds within 5 km will be detected. Attenuation also results in different DWR for clouds with the same drop spectrum at different heights. The value and vertical distribution of IWC affect the value of DWR and the thickness of the clouds detected by electromagnetic wave. The attenuation increases with the increase of IWC and the electromagnetic wave attenuation of high frequency cloud radars is larger， that make the DWR larger， so the DWR is related to the number concentration of the spectrum. As a result， the attenuation correction is very important when using DWR retrieval.