kasacrcfrspcvptcross (a1)

The Ka-Band Scanning ARM Cloud Radar (KASACR) records cloud properties. ARM'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). Beamwidths 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. KASACR 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扫描云雷达为安装于统一扫描转台的双频双偏振多普勒雷达，每套转台搭载一台峰值功率2kW的Ka波段雷达，而第二台雷达的频段则根据部署位置而定，可选峰值功率1.7kW的W波段雷达，或峰值功率20kW的X波段雷达。Ka波段与W波段配对时的波束宽度大致匹配，约为0.3度；X波段波束宽度约为1度。由于天线波束宽度极窄，ARM扫描云雷达采用了区别于常规气象雷达的扫描策略：KASACR并未聚焦于平面位置显示器（Plan Position Indicator, PPI）扫描模式，而是在多个方位角下采用距离高度显示器（Range Height Indicator, RHI）扫描模式，以获取云体三维体积数据。KASACR采集的测量参数包括同偏振与交叉偏振雷达反射率、多普勒速度、非扫描状态下的谱宽与频谱，以及线性退极化比。2018至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）野外试验所获取的KASACR数据，目前已以b1级产品形式发布。相较于原始CACTI业务数据，b1级产品经过了全面的分析与校正，数据质量得到显著提升：数据已完成跨点校准，针对试验期间出现的业务问题对数据流进行了修正，并集成了多套数据质量掩码及基础衍生产品。如需获取更多详情，请参阅《CACTI雷达b1级处理报告》。