Featured Research

from universities, journals, and other organizations

Radar-Processing Algorithm Produces High-Resolution Lunar Images

Date:
November 5, 1998
Source:
University Of Illinois At Urbana-Champaign
Summary:
Superior radar images of the moon, inner planets and asteroids are possible with a "polar-format" radar-processing algorithm developed at the University of Illinois. The algorithm, from spotlight-mode synthetic aperture radar, provides improved image quality over conventional processing, without an excessive increase in computational requirements or complexity.

CHAMPAIGN, Ill. -- Superior radar images of the moon, inner planets and asteroids are possible with a "polar-format" radar-processing algorithm developed at the University of Illinois. The algorithm, from spotlight-mode synthetic aperture radar, provides improved image quality over conventional processing, without an excessive increase in computational requirements or complexity.

"In astronomy, radar reflectivity data are sometimes used to supplement other types of observations," said David Munson, a U. of I. professor of electrical and computer engineering. "Radar measurements, for example, have proven particularly useful for imaging Venus, where a thick layer of clouds perpetually obscures the planet's surface. Oftentimes, however, the radar images produced from Earth-based measurements are of poor quality."

Conventional radar-imaging systems are based on range-Doppler techniques, Munson said. "But in the time it takes to collect astronomical data -- typically 10 to 20 minutes -- the object's rotation causes both the range and the radial velocity of reflectors to change with time. Because conventional range-Doppler processing makes no allowance for this relative motion, the resulting image is blurred."

The polar-format, spotlight-mode synthetic aperture radar approach avoids this problem by affixing a spatial-domain coordinate system to the target. As the object rotates with respect to the radar, the coordinate system rotates with it, thus avoiding smearing in the image.

Munson, former graduate student Jennifer Webb (now a researcher at Texas Instruments) and Nick Stacy, a researcher with the Microwave Radar Division of the Defense Science and Technology Organization in Australia, recently applied the polar-format radar-processing algorithm to lunar reflectivity data collected at Arecibo Observatory in Puerto Rico.

"Although the moon constantly presents the same face toward Earth, we get to see it from different angles as it moves," Munson said. "And in our mathematical model, that's all that's required. The principle employed is nearly identical to that used in computer tomography in medical imaging."

The high-resolution lunar images produced by the researchers were far superior to what had been obtained in the past with conventional radar-processing techniques. "The amount of computational work was only three times what was formerly required," Munson said. "So, with a small increase in computational effort, we can get vastly improved imaging."

As an additional benchmark, the researchers compared their images with those obtained with another approach developed by Stacy, called focused range-Doppler processing. This latter technique "produces the best known results, but is much more expensive, computationally," Munson said. "Our polar-format processing algorithm performed nearly as well, with considerably less effort."

The researchers describe their algorithm and present their results in the November issue of IEEE Transactions on Image Processing.


Story Source:

The above story is based on materials provided by University Of Illinois At Urbana-Champaign. Note: Materials may be edited for content and length.


Cite This Page:

University Of Illinois At Urbana-Champaign. "Radar-Processing Algorithm Produces High-Resolution Lunar Images." ScienceDaily. ScienceDaily, 5 November 1998. <www.sciencedaily.com/releases/1998/11/981105070048.htm>.
University Of Illinois At Urbana-Champaign. (1998, November 5). Radar-Processing Algorithm Produces High-Resolution Lunar Images. ScienceDaily. Retrieved September 16, 2014 from www.sciencedaily.com/releases/1998/11/981105070048.htm
University Of Illinois At Urbana-Champaign. "Radar-Processing Algorithm Produces High-Resolution Lunar Images." ScienceDaily. www.sciencedaily.com/releases/1998/11/981105070048.htm (accessed September 16, 2014).

Share This



More Matter & Energy News

Tuesday, September 16, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Space Race Pits Bezos Vs Musk

Space Race Pits Bezos Vs Musk

Reuters - Business Video Online (Sep. 16, 2014) Amazon CEO Jeff Bezos' startup will team up with Boeing and Lockheed to develop rocket engines as Elon Musk races to have his rockets certified. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
MIT's Robot Cheetah Unleashed — Can Now Run, Jump Freely

MIT's Robot Cheetah Unleashed — Can Now Run, Jump Freely

Newsy (Sep. 16, 2014) MIT developed a robot modeled after a cheetah. It can run up to speeds of 10 mph, though researchers estimate it will eventually reach 30 mph. Video provided by Newsy
Powered by NewsLook.com
Manufacturer Prints 3-D Car In Record Time

Manufacturer Prints 3-D Car In Record Time

Newsy (Sep. 15, 2014) Automobile manufacturer Local Motors created a drivable electric car using a 3-D printer. Printing the body only took 44 hours. Video provided by Newsy
Powered by NewsLook.com
Refurbished New York Subway Tunnel Unveiled After Sandy Damage

Refurbished New York Subway Tunnel Unveiled After Sandy Damage

Reuters - US Online Video (Sep. 15, 2014) New York officials unveil subway tunnels that were refurbished after Superstorm Sandy. Nathan Frandino reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

    Environment News

      Technology News



      Save/Print:
      Share:

      Free Subscriptions


      Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

      Get Social & Mobile


      Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

      Have Feedback?


      Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
      Mobile: iPhone Android Web
      Follow: Facebook Twitter Google+
      Subscribe: RSS Feeds Email Newsletters
      Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins