Ka-Band Scanning ARM Cloud Radar (KASACR) Hemispherical Sky RHI Scan - kasacrhsrhi

The Ka-Band Scanning ARM Cloud Radar (KASACR) records cloud properties. \n \nARM's scanning cloud radars are dual-frequency, dual-polarization Doppler radars mounted on a common scanning pedestal. Each pedestal includes a Ka-band radar (2kW peak power) and the deployment location determines whether the second radar is a W-band (1.7 kW peak power) or an X-band (20 kW peak power). \n \nBeamwidths for Ka-bands paired with W-bands are roughly matched at 0.3 degrees. The X-band beamwidth is approximately 1 degree. Due to the narrow antenna beamwidth, ARM s scanning cloud radars use scanning strategies unlike typical weather radars. Rather than focusing on plan position indicator, or PPI, scans, the KASACR uses range height indicator, or RHI, scans at numerous azimuths to obtain cloud volume data. Measurements collected with the KASACR are copolar and cross-polar radar reflectivity, Doppler velocity, spectra width and spectra when not scanning, and linear depolarization ratio. \n \nKASACR data from the 2018 2019 Cloud, Aerosol, and Complex Terrain Interactions (CACTI) field campaign in Argentina are now available as b1-level products. Building on the original CACTI operational data, the b1-level products feature improved data quality resulting from extensive analyses and corrections. The data are cross-calibrated to a common point, datastreams are corrected for operational issues that occurred during the campaign, and several data quality masks and basic derived products are incorporated. For more information, read the CACTI radar b1-level processing report.

Ka波段扫描ARM云雷达（Ka-Band Scanning ARM Cloud Radar，KASACR）用于记录云系特性。

ARM的扫描型云雷达为双频双极化多普勒雷达，搭载于统一扫描转台。每台转台包含一部Ka波段雷达（峰值功率2kW），第二部雷达的波段由部署位置决定，可选配W波段雷达（峰值功率1.7kW）或X波段雷达（峰值功率20kW）。

Ka波段与W波段配对使用时，波束宽度大致匹配，约为0.3°；X波段的波束宽度约为1°。由于天线波束极窄，ARM扫描云雷达采用与常规天气雷达迥异的扫描策略：其并未聚焦于平面位置指示（Plan Position Indicator，PPI）扫描，而是通过在多个方位角上开展距离高度指示（Range Height Indicator，RHI）扫描，以获取云体三维体积数据。KASACR采集的测量参数包括同极化与交叉极化雷达反射率、多普勒速度、非扫描模式下的谱宽与频谱，以及线性退极化比。

目前已公开2018-2019年在阿根廷开展的云、气溶胶与复杂地形相互作用（Cloud, Aerosol, and Complex Terrain Interactions，CACTI）野外试验的KASACR b1级数据产品。该系列产品基于原始CACTI业务数据，经过深入分析与校正后实现了数据质量升级：数据已完成交叉校准至统一基准，针对试验期间出现的业务问题完成了数据流校正，并集成了多套数据质量掩码及基础衍生产品。如需了解更多细节，请参阅《CACTI雷达b1级处理报告》。