Development of a multi-frequency airborne radar instrumentation package for ice sheet mapping and imaging

We have developed improved versions of three different radar systems and integrated them as an airborne instrumentation suite for sounding and imaging Polar ice sheets. The first instrument is a multi-channel, coherent pulsed chirp radar operating at VHF with up to 30 MHz bandwidth. This radar set is capable of sounding a few-kilometer thick ice while flying at altitudes up to 10 km above mean sea level. The second instrument is designed to operate at UHF using a burst of narrow-bandwidth signals to digitally synthesize a bandwidth in excess of 300 MHz. This apparatus is used to measure internal layers of the ice sheet to a depth close to 100 m. The third component to the instrumentation package is a microwave frequency-modulated continuous wave (FMCW) radar, which is used to measure the ice sheet surface elevation profile with centimeter accuracy. We are presenting a description of each system along with field test results that validate the performance of the instrument package.