Polarimetric Atmospheric Imaging Radar (PAIR): Antenna Design, Testing, and Validation

Polarimetric phased array radars for weather applications require antennas with high co-polar beam matching and low cross-polarization levels to successfully estimate polarimetric meteorological products. In this communication, the authors present the design and validation of a dual-polarized, balanced probe-fed, stacked microstrip patch antenna operating in C-band (5.3 - 5.6 GHz) for the mobile Polarimetric Atmospheric Imaging Radar (PAIR), developed at the Advanced Radar Research Center (ARRC), University of Oklahoma (OU). The design of the antenna exploits balanced probe-fed feeding technique with thin dielectric substrates and low dielectric permittivities to suppress cross-polarized radiation. Simulation and measured results show scanning capabilities for $-45^{\circ}\leq\theta\leq 45^{\circ}$ and $0^{\circ}\leq\phi\leq 180^{\circ}$ for all designed frequencies. Within the 3-dB width of the imaging beam intended to scan with PAIR, the antenna exhibits co-polar beam mismatch lower than 0.1 dB and cross-polarization levels under -40 dB, based on simulations and measured results.