A Dual-Polarized 2-18-GHz Vivaldi Array for Airborne Radar Measurements of Snow

This communication presents the experimental results of a ultrawideband 2-18-GHz dual-polarized Vivaldi antenna array for airborne radar measurements of snow. The antenna design is based on the previously reported all-metal flared-notch array by Kindt and Pickles for operation over the frequency range 0.7-9 GHz. An antenna array prototype consisting of 8 x 8 active dual-polarized elements was fabricated with precise aluminum machining and tested in the anechoic chamber. Beamsteering upto 30 degrees was experimental demonstrated from 2 to 18 GHz. The measurement results are in a good agreement with the full-wave simulation results in both polarization configurations. Preliminary sample results from data collected using the Vivaldi array are also presented. The antenna array enables full polarimetric measurements of snow-over-sea-ice for estimating the snow-water-equivalent (SWE), as well as fine-resolution mapping of snow-air and snow-ice interfaces for estimating thickness.