These pages describe the current status and preliminary test results of the delay/Doppler phase-monopulse (D2P) radar which is being built and tested by the Space Department of the Johns Hopkins University Applied Physics Laboratory under funding from NASA.
Two test flights of this radar have been conducted from the Patuxent River Naval Air Station in late March and early April of 2000. Overflights of the Greenland Ice sheets were conducted during June of 2000. The data from these flights is being processed in order to demonstrate the capabilities of a properly designed radar altimeter for measurement of the grounded ice of Greenland and Antarctica. Much of the data from the June 14 flight has been processed and is available for viewing here.
In May 2002 the D2P radar was deployed alongside the NASA Airborne Topographic Mapper on a series of flights over Greenland and Svalbard, Norway as part of the LaRa experiment. The participation of the D2P was an add on to the annual NASA Greenland ice sheet mapping mission. The primary goal of the LaRa experiment is the intercomparison of the laser-based ATM and the D2P radar altimeter over a variety of land and sea ice conditions.
Current funding for the D2P Project comes from the Instrument Incubator Program at NASA. "The Instrument Incubator fosters the development of innovative remote-sensing concepts and the assessment of these concepts in ground, aircraft, or engineering model demonstrations." This program supported the fabrication of the system, the current test campaign, and the completion of a design that was begun with support from the Integrated Program Office. Initial support for the analysis of the delay/Doppler concept and computer simulations of its performance were supported by the Office of Naval Research.
The altimeter innovations that are being demonstrated with the D2P altimeter are being employed by the European CryoSat mission. The goal of this mission "is to study possible climate variability and trends by determine variations in thickness of the Earth's continental ice sheets and marine sea ice cover."