热带气象学报2018，Vol.34Issue(2)：260-267,8.DOI:10.16032/j.issn.1004-4965.2018.02.012
机载W波段雷达衰减订正方法的不同云型模拟对比研究
A STUDY ON ATTENUATION CORRECTION TO DIFFERENT CLOUD TYPES AT W BAND OF AIRBORNE RADAR
摘要
Abstract
In order to explore the attenuation correction algorithm for airborne W-band (94GHz,3.2 mm)cloud radar,radar echoes for five typical non-precipitating clouds and attenuation corrections with five correction algorithms are simulated based on radar equation with atmospheric and cloud attenuation.And the best coefficients in kc=aZb and the effects of cloud parameters such as cloud water content,droplet number density,height and thickness on correction error are also studied.The results show that the coefficientsa=5.096 5 and b=0.491 9 in kc=aZb for W-band are best suitable for stratocumulus rather than stratus,nimbostratus,and cumulus,and the performance of bin-by-bin algorithms is generally better than the algorithms from Hitschfeld-Bordan and Meneghini.If the best coefficients inkc=aZb for individual clouds are used,all the five correction algorithms are suitable for either type of clouds and the relative errorsare less than 5％ even if the cloud thickness increases to 2 times the typical value.In case that the cloud parameters vary a lot from the typical values,the 3 bin-by-bin algorithms,though R3 is slightly better than the other two(R2 and R1),can still make the relative errorsless than 10％ as long as the cloud is not very thick.If the criteria ψ ≤ 10％ or 20％ is used for assessment,the 3 algorithms are most suitable for much different types of clouds as compared with the Hitschfeld-Bordan and Meneghini algorithms.But the bin-by-bin algorithms are sensitive to cloud water content,variation in cloud water content from the typical value leads to a decreased correctable thickness or an increased error.Therefore a good estimation of cloud water content is required in case either of the 3 bin-by-bin algorithms is used for attenuation corrections.关键词
机载测云雷达/W波段/衰减订正/云探测/模拟仿真Key words
airborne cloud radar/W band/attenuation correction/cloud sounding/simulation分类
天文与地球科学引用本文复制引用
纪雷,王振会,黄兴友,张培昌..机载W波段雷达衰减订正方法的不同云型模拟对比研究[J].热带气象学报,2018,34(2):260-267,8.基金项目
国家自然科学基金(41675028、40875016) （41675028、40875016）
国家高技术研究发展计划(863)(2007AA061901)共同资助 （863）
