Ka-Band Scanning ARM Cloud Radar (KASACR) PPI - kasacrppi

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 Ka-SACR uses range height indicator, or RHI, scans at numerous azimuths to obtain cloud volume data. Measurements collected with the Ka-SACR are copolar and cross-polar radar reflectivity, Doppler velocity, spectra width and spectra when not scanning, and linear depolarization ratio.

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，搭载于同一扫描转台。每台转台包含一台Ka波段雷达（峰值功率2kW），且根据部署位置的不同，第二台雷达可为W波段（峰值功率1.7kW）或X波段（峰值功率20kW）。

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。由于天线波束极窄，ARM的扫描型云雷达采用与常规天气雷达迥异的扫描策略。Ka-SACR并未采用主流的平面位置指示（Plan Position Indicator，PPI）扫描模式，而是在多个方位角下开展距离高度指示（Range Height Indicator，RHI）扫描，以获取云体体积数据。该设备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。