New NRL Project to Improve CReSIS Radars


By Bill Daehler
Summer 2013

Dr. Stephen Yan is working on a project for the U.S. Naval Research Laboratory (NRL) that will enhance several of the radar technologies developed by CReSIS.

“We are developing an upgraded and integrated version of our Snow and Ku-band radars,” said Yan, an assistant scientist at CReSIS.

The Snow radar is used to measure the thickness of snow over sea ice. The Ku-band radar altimeter is used over ice sheets to make high-precision surface elevation measurements. These radars have both been attached to aircraft to survey ice sheets and sea ice in Greenland and Antarctica.

The Snow radar currently runs over 2-8 GHz and can detect the snow-ice interface and layers down to 70 meters; the Ku-band altimeter runs over 12-18 GHz and can detect the air-snow interface. CReSIS has a well-known track record of developing and deploying ice-sounding radar, most recently on missions with NASA’s Operation IceBridge. The NRL project seeks to improve the performance of some of these systems.

“The radar that we are developing for NRL will operate from 2-18 GHz and therefore is an ultrawideband radar system,” said Yan. “The new radar system will also feature dual-polarization and beam-steering, so that we can measure the backscattering characteristics of snow and determine snow-water equivalent (SWE).”

SWE is the product of snow density and depth—it’s a very important parameter for hydrological studies because it tells researchers about the amount of water that could run off.

Radar Echograms

Image 1: Radar echograms of data collected in the Arctic (top) and the Antarctic (bottom) using the Snow radar. Courtesy of Stephen Yan, CReSIS.

Yan said the project will take advantage of the new CReSIS Anechoic Chamber, which was opened last year. The chamber will help the research team with system response measurement and for “the characterization of the under-developing 2-18GHz dual-polarized antenna array,” according to Yan.

Yan said he plans on delivering a preliminary system by January 2014 and then continuing to make upgrades. The NRL contract is for two years with an optional extension of one year. Yan’s research team currently includes two Graduate Research Assistants (GRAs): Daniel Gomez-Garcia and Masud Aziz, both of whom are Ph.D. students in Electrical Engineering. During the fall semester, a new Master’s student, Jay McDaniel, will join the team.

Dr. Stephen Yan

Photo 2: Dr. Stephen Yan, CReSIS Assistant Research Professor.

The NRL project will build upon work by CReSIS Director Dr. Prasad Gogineni, Deputy Director Dr. Carl Leuschen, and Assistant Research Professor Dr. Fernando Rodriguez-Morales—who have long worked on the Snow and Ku-band radars.

“Their effort is an important factor for the award of the project,” said Yan.

The NRL is the U.S. Navy’s research lab, “a broadly based multidisciplinary program of scientific research and advanced technological development directed toward maritime applications of new and improved materials, techniques, equipment, systems and ocean, atmospheric, and space sciences and related technologies,” according to the NRL.