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THE CUTTING EDGE

Radar-Imaging Company Sees Niche in Dark

Aerospace: RDL Space plans to launch first commercial satellite that uses radio waves to photograph objects on Earth.

September 14, 1998|KAREN KAPLAN | TIMES STAFF WRITER

After U.S. missiles bombed a suspected terrorist camp in Afghanistan last month, cloud cover and darkness prevented the world from seeing the full impact of the attack for several days. But if Radar1 had been orbiting the Earth, detailed images of the destruction could have been made available in as little as 12 hours.

So say executives at RDL Space Corp., the Culver City company behind Radar1. RDL Space plans to launch the first commercial satellite that uses radar to see the planet's surface through clouds, bushes and even darkness.

Using a technology first developed in the 1930s that helped Britain's Royal Air Force defeat the Germans during World War II, RDL Space hopes to carve itself a niche in the growing market for satellite images, which for decades has been dominated by electro-optical pictures, which are prized for their photograph-like quality.

Electro-optical satellites work essentially like giant cameras, sensing and recording light to produce full-color pictures. Radar, on the other hand, relies on reflected radio waves, which can't see colors but can reveal the shape of objects based on how the waves bounce off them.

That means a radar satellite doesn't depend on daylight or clear weather to take an image. It also means that radar sensors can identify water, metal and other particularly reflective surfaces.

Altogether, those capabilities should make a radar satellite a valuable tool for purposes as diverse as tracking oil spills, documenting illegal fishing and measuring the moisture in agricultural fields, said Birendra "Raj" Dutt, president and chief executive of Research & Development Laboratories, RDL Space's parent company.

The Jet Propulsion Laboratory in Pasadena launched the first radar-sensing satellite in 1978 to monitor the oceans. Today, the governments of Canada and Japan and the European Space Agency operate radar-sensing satellites of their own, and JPL is preparing to launch its third radar satellite--to measure winds over the oceans--in November.

But RDL Space's Radar1 is aiming to become the first commercial satellite to provide radar imaging. In June, the company won the first U.S. license for a commercial radar satellite from the National Oceanic and Atmospheric Administration, and it's now applying for another critical license from the Federal Communications Commission.

When it becomes operational in 2001, Radar1 will be able to produce an image of almost any place on Earth precise enough to make objects as small as 5 meters (about 16 1/2 feet) across recognizable, and it will deliver that image to the customer within 12 hours, Dutt said. The satellite will have the capability to see things as small as 1 meter (about 3 feet, 4 inches), but will need a waiver from the U.S. government to sell images with such high resolution, he said.

To make an image, Radar1 will beam 2,000 to 4,000 radio pulses per second--the more pulses, the better the resolution--from a transmitter for one to three seconds. Each pulse will hit the Earth's surface and bounce off, with some portion of the pulse returning to the satellite. Radar1 will record information about the shape of the returning radio waves and send that data to one of several planned ground-link stations on Earth.

From there, the data will travel via fiber-optic cable to a Radar1 control center planned for northern Virginia. Computers will translate the information about the shape of the pulses into a corresponding shade of black, white or gray. Smooth and metallic surfaces that are highly reflective register as black, while rough surfaces that completely scatter the radio waves will show up as white.

"The signals tell you the different features in the terrain and features on the objects they're hitting," said Chris Haakon, chief executive of Autometric, the Springfield, Va., firm that will run the Radar1 control center.

Images Could Offer Valuable Information

The computers produce an image that looks like a black-and-white photograph.

But "the image is just the starting point," Dutt said. "It's the information in the image that's important."

Reading a satellite image isn't as simple as reading a newspaper. A nuclear testing site in India would be difficult for a layman to spot, but it would be recognizable to an intelligence officer who knows what telltale signs to look for, Dutt said. Autometric will use its cadre of image analysts, built up during decades of government work, to interpret the images.

Depending on customer demand, some images will also get "value-added processing," such as colorization to highlight certain characteristics, Haakon said. Images can also be warped to look as if they were taken from a different angle, blended with other images or adorned with contour lines and labels, he added.

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