An airborne pod-mounted dual beam interferometer

Dual beam interferometer (DBI) has been developed by the University of Massachusetts (UMass) to study ocean surface waves and currents in coastal regions. This airborne radar operates at C-band (5.3 GHz) with a bandwidth of 25 MHz and VV polarization. DBI consists of two pairs of microstrip patch array antennas, one squinted 20deg forward of broadside and the other 20deg aft. Each pair of antennas is separated in the along-track direction a distance of 1.23 meters forming an interferometer. Over several years, DBI was flown on a National Oceanic and Atmospheric Administration´s WP-3D research aircraft in a number of successful missions collecting the data both over land and ocean. These deployments and subsequent data analysis were carried out in collaboration with Naval Research Laboratory (NRL). This paper describes the hardware integration and use of the system to generate surface current vector maps