Calibrating the Airborne Ka-Band Precipitation Radar Aboard the Univ. of Wyoming King Air Research Aircraft

A new radar, Ka-band Precipitation Radar (KPR), was recently added to the instrument suite aboard the University of Wyoming King Air (UWKA) Research Aircraft. The KPR operates from a standard Particle Measurement System (PMS) canister mounted at the wing tip of the UWKA. The radar features a 10W solid-state transmitter and a pair of flat plate antennas for collecting data above and below the aircraft. The transmitted waveform consists of a linear frequency modulated (chirped) pulse followed by an offset frequency short RF pulse. To effectively characterize this instrument, three cross-calibrations are performed – (1) the compression gain of the chirped pulse is calibrated using the short pulse return from co-located sample volumes; (2) the down antenna is calibrated using returns from the up antenna during carefully selected, time-averaged, flight legs; (3) the KPR is cross-calibrated with the W-band Wyoming Cloud Radar (WCR), also aboard the UWKA, using appropriate weather targets. This work will describe, in detail, the steps taken to calibrate the KPR.