A Wideband Airborne Ice Sounding/Imaging Radar Deployment – KU CReSIS

News

By Stephen Yan
Winter 2014

ANSYS Logo

The Center for Remote Sensing of Ice Sheets (CReSIS) at the University of Kansas is an NSF-Funded Science and Technology Center for the development of new technologies and models that measure and predict the dynamics of ice sheets in Greenland and Antarctica. We recently successfully deployed our first wideband airborne ice sounding/imaging radar in Antarctica. The system operates over a frequency range of 200-450 MHz and is designed for collecting fine-resolution (approx. 60 cm) measurements of ice sheet thickness, mapping internal layers in ice, and imaging the ice-bed interface. The radar is carried by a Kenn Borek Air (KBA) Basler-67 aircraft outfitted with a 4 m-long, fuselage-mounted eight-element antenna array. During the test flight on the Ross Ice Shelf near McMurdo Station, Antarctica, we performed in-flight radiation pattern measurements. The in-flight measured array-patterns agreed very well with simulated results from the ANSYS High Frequency Structure Simulator (HFSS). Collecting antenna-pattern measurements in-flight allows us to identify antenna platform integration effects, quantify our transmit channel equalization, and calibrate the radar more accurately. With the new system, we have successfully sounded the ice sheets around the Whillans Ice Stream in West Antarctica. In the future, we plan to expand the bandwidth of the system to 150-600 MHz, as well as add two wing-mounted eight-element arrays so as to increase the radar resolution and sensitivity.

Data from Antarctica

Top: Location of the experiment in Antarctica and visualization of the simulated array pattern at the field camp.

Middle left: Basler aircraft taking off with the array mounted under the fuselage.

Middle right: Comparison between in-flight-measured (with linear chirp excitation) and HFSS-simulated radiation patterns.

Bottom: Sample radar echogram collected over the Whillans Ice Stream, Antarctica.