kasacrslr (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）用于记录云的各类属性。ARM扫描云雷达为搭载于统一扫描转台的双频双极化多普勒雷达。每套转台搭载一台峰值功率2kW的Ka波段雷达，第二台雷达的波段由部署位置决定，可选峰值功率1.7kW的W波段，或峰值功率20kW的X波段。Ka波段与W波段组合时的波束宽度大致匹配，约为0.3°；X波段波束宽度约为1°。由于天线波束宽度极窄，ARM扫描云雷达采用了与常规天气雷达迥异的扫描策略。KASACR并未采用常规的平面位置指示（plan position indicator, PPI）扫描模式，而是通过在多个方位角上执行距离高度指示（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，现已以b1级产品形式对外发布。相较于原始CACTI业务数据，b1级产品经过全面分析与校正，数据质量得到显著提升：数据已交叉校准至统一基准，针对试验期间出现的各类业务问题对数据流进行了校正，并集成了多套数据质量掩码与基础衍生产品。如需了解更多细节，请参阅《CACTI雷达b1级处理报告》。