National Severe Storms Laboratory Seminar Series presents...
Polarimetric Frequency Scanning Cylindrical Array Radar with High Isolation for Weather Measurements
Advanced Radar Research Center
15 November 2012, 1:15 PM
National Weather Center, Room 1350
120 David L. Boren Blvd.
University of Oklahoma
It has been demonstrated that phased array radar’s pulse-to-pulse beam steering capability enables accurate meteorological measurements with fast data update. The higher temporal resolution (< 1 min) than that (~ 6 min) obtained with a mechanically scanning beam has revealed detailed evolutions of severe storm phenomena such as tornados and microbursts. The cylindrical polarimetric phased array radar (CPPAR), is recently proposed for weather measurements to overcome the deficiencies encountered with a planar polarimetric phased array radar (PPPAR). Some recent studies on CPPAR have shown that CPPAR is arguably best suited for fast weather surveillance with dual-polarization capability; however, some more studies are needed to show the desired polarimetric performance is feasible. The Advanced Radar Research Center at the University of Oklahoma has recently been designing and developing a cylindrical phased array radar to demonstrate the performance of such a system. In order to simplify the radar design of this demonstrator and avoid the phase shifters, the frequency scanning array concept has been suggested. Frequency scanning array antenna is a special case of series fed phased array antennas, where beam scanning occurs by changing the frequency of the exciter. Although the design of frequency scanning microstrip array antenna has been studied for many years, dual-polarization capability with high cross-polarization isolation and low sidelobe requirements make the antenna design cumbersome and challenging. Multi-layer technology can substantially improve the performance of a dual-polarization array regarding the isolation and cross-polar pattern. The main goal of this seminar is to demonstrate the performance of a dual-polarization frequency scanning array radar which meets the requirements for weather measurements.