测云雷达 meaning in Chinese
cloud detection radar
cloud-detection radar
Examples
- Cloud detection radar
测云雷达 - As for a space - based cloud radar , the change of the radar reflectivity n and the change of attenuation rate along with the cloud liquid water content have been compared between 37 ghz and 94ghz . the transmittance t of single level cloud for different heights and liquid water content has also been calculated at 2 frequencies . by defining a = n tr , which combines both effects of radar reflectivity and transmittance , we have examined the values of a at 37ghz and 94ghz for high , middle and low cloud liquid water contents
对空间测云雷达，讨论了37ghz和94ghz这两个频率的雷达反射率和衰减系数随云液水含量的变化；计算了不同高度的单层云在不同频率，不同含水量情况下的云层透过率_ ；定义a = _来综合考虑雷达反射率和透过率对空间测云雷达回波的影响，分析比较了云含水量高、中、低时37ghz和94ghz的a值大小。 - Main conclusions drawn from the analyses of calculating results are as follows : ( 1 ) the microwave absorption of atmosphere gas have obvious attenuation at the wavelengths for cloud detection , thereinto , the water attenuation effect changes greatly , so the 94ghz cloud detecting radar should have water vapor attenuation correction scheme . ( 2 ) when 37ghz and 94ghz radars detect clouds , the difference between the atmosphere and cloud attenuation and the large variety of radar reflectivity conduce the intension of the radar backscatter signals change . ( 3 ) for the thin cloud layer and low water content of cloud , 37 - ghz radar backscatter signals are not as good as 94 - ghz radar , that is to say that the 94ghz radar has better capability in thin clouds detection
本工作得出如下结论： ( 1 )大气气体的微波吸收在测云波段产生明显的衰减，其中水汽衰减效应变化很大；即将上天的空间94ghz测云雷达必须有水汽衰减订正方案； ( 2 ) 37ghz和94ghz雷达测云，由于大气和云衰减不同和雷达反射率的很大差异，导致雷达回波信号强弱不同； ( 3 )对云层较薄、含水量较少的云，在不计雷达参数的情况下， 37ghz雷达回波信号不如94ghz测云雷达，也就是说94ghz对薄云有更强的探测能力；对云层较厚、含水量大的云，由于强衰减的作用， 94ghz雷达回波信号小于37ghz雷达； ( 4 )从大气衰减的不利因素方面考虑，空间94ghz雷达测高层薄云的效果最好；测低层薄云时需要考虑气体衰减订正；因浓厚云的强衰减作用，探测其中下部的能力大大减弱，不仅要进行衰减订正，而且要借助其他信息来反演整个云层的含水量垂直分布； （ 5 ）为了获得从极薄到极浓厚云的垂直分布探测能力，未来测云雷达系统最好采用双波长甚至三波长（如94 、 37和13ghz ） 。