Multispectral data add versatility to high-resolution satellite imagery.
Sensor fusion is taking place within the commercial remote sensing arena as military users combine different forms of satellite imagery to generate advanced intelligence and mission planning products. This imagery also is being combined with data from diverse sources such as unmanned aerial vehicles (UAVs) and topographical archives to redefine geospatial information.
A cornerstone of the military’s commercial imagery exploitation is the U.S. Air Force’s Eagle Vision. Originally built around using imagery from France’s Spot satellite acquired by a Matra groundstation, the program now can tap many of the new commercial remote sensing satellites that have reached orbit over the past few years. And, computer and electronics advances have reduced the size of the system’s equipment to enhance mobility and increase versatility.
Eagle Vision’s original goal was simply to speed satellite imagery into the hands of the warfighter. The keys to this achievement were mobile downlink capabilities and access to high-resolution commercial remote sensing data. Now, however, its capabilities have been enhanced by a plethora of new and different commercial remote sensing satellites combined with mission planning systems that can wrap the imagery around terrain data for true three-dimensional (3-D) dynamic models.
Eagle Vision currently incorporates remote sensing imagery from Spot, Landsat, Canada’s Radarsat and the European radar satellite ERS. Ongoing upgrades and plans aim to incorporate imagery from the Indian Remote Sensing (IRS) satellite, Orbview and Earthwatch. This will allow users to meld different types of remote sensing imagery and process it with topographical data to generate 3-D terrain models. Adding data from UAVs and other theater surveillance and reconnaissance platforms provides even more capabilities and applications.
“We are at the second stage of warfighters’ utilization of commercial imagery,” maintains Col. James G. Clark, USAF. Col. Clark, director of the Air Force Modeling and Simulation Office, assistant vice chief of staff, U.S. Air Force, notes that the advent of 1-meter imagery has moved military exploitation of commercial remote sensing satellites into a new realm.
U.S. Army topographic engineers at Fort Belvoir, Virginia, have developed some innovative ideas for using the system. Many of these involve false-color multispectral imagery that reveals artificial items among natural features. Real tanks, for example, can be discerned from wood decoys. Multispectral imagery also can reveal the depression left by tank treads.
“Commercial imagery is a very powerful supplement to our intelligence sources,” Col. Clark declares. “The U.S. Air Force is one of the largest consumers of commercial imagery in the world.”
Eagle Vision’s advantage lies in its ability to download and process satellite imagery in the field. Instead of waiting for remote sensing data to arrive in theater from distant groundstations via a national command center, a deployed Eagle Vision receives imagery downloads as the satellite passes overhead. If the satellite is scanning a nearby battlefield, the imagery is processed in near real time. Users can task the commercial satellite to scan specific areas as needed.
Having this capability also permits a theater commander to monitor his own facilities and take remedial action to forestall an attack. Vulnerabilities that would be revealed to an adversary can be discovered and rectified before the foe can even receive the same imagery through conventional means.
For example, Spot employs two panchromatic cameras, each providing 60-kilometer-wide swaths of coverage. When the Eagle Vision groundstation dish locks onto the satellite as it passes within range of its theater deployment, it can accumulate as much as a 5,000-kilometer path of imagery 120 kilometers across. Landsat’s multispectral imaging system can provide the same length of coverage as wide as 185 kilometers, although at less resolution than Spot.
In remote areas where military leaders had not anticipated operations, Eagle Vision can provide vital geographic data. “Having a brand-new Landsat or Spot scene of an area certainly is better than an old colonial map” for contingency operations, Col. Clark relates.
Timely access to remote sensing imagery becomes more important in areas that undergo significant seasonal changes. An image of heavily forested mountains in the summer bears little resemblance to its winter counterpart that reveals snow-covered mountainous terrain dotted with leafless trees. In Bosnia and Herzegovina, for example, U.S. military engineers trying to span the Sava River with a pontoon bridge found themselves awash when the river overflowed its banks during flooding season.
The proliferation of commercial high-resolution remote sensing satellites has spawned the fear that virtually any country—or even organization—could acquire timely imagery of a crisis area. Col. Clark offers that, in practice, most nations do not have the available groundstations to access this imagery in near real time. Accordingly, it will take at least two weeks for an adversary to receive the imagery. The mobile Eagle Vision, on the other hand, can acquire its imagery as the satellite is passing overhead.
Currently, two Eagle Vision units are deployed and two more are in the pipeline. One deployed system is at Ramstein Air Base, Germany. The other, which is funded by the National Reconnaissance Office, is at the U.S. Army Topographic Engineering Center in Fort Belvoir. Eagle Vision III is designated for the 152nd Intelligence Squadron, Air National Guard at Reno, Nevada. Eagle Vision IV is slated for an October delivery to the Air National Guard at McEntire Air National Guard Base, South Carolina.
The system has undergone several iterations. While Eagle Visions I through IV are complete systems, Eagle Vision also has taken the form of test upgrades in Renaissance View and National Eagle. Three tests were deployed: Pacific Eagle, Joint Eagle and Nellis Eagle. All four Eagle Visions will be upgraded to incorporate the advances developed in each one.
The new versions improve on the original in both capability and mobility. Eagle Vision I employed a 3.8-meter satellite dish for single-band uplink and single-band downlink communications, and the entire system required two C-130 aircraft to deploy to the field. The Renaissance View configuration, which first incorporated Radarsat imagery in 1996, also used commercial Sun computer hardware for a smaller size. The original fixed-shelter processing van evolved into four transportable cases, which allowed the entire system to be transported onboard a single C-130.
National Eagle built on that configuration by reincorporating the original processing van. This unit was equipped with workstations to allow operators to process a tape of national imagery to National Imagery and Mapping Agency (NIMA) standard for combining with the commercial and Predator UAV imagery. This in turn could be combined with PowerScene, the Air Force mission planning system and the portable flight planning system (PFPS) Falcon View. The National Eagle system has become Eagle Vision III at Reno, and it will become operational in June.
This unit is deployed at the Air National Guard to explore and exploit its capabilities in dealing with contingency operations. Col. Clark explains that the Guard can use Eagle Vision while responding to situations such as forest fires, earthquakes, storms and other disasters. Federal and state government officials can exploit the system’s multispectral remote sensing to track fires and flooding, for example.
Eagle Vision IV’s forte is in communicating its imagery. Communications experts at McEntire Air National Guard Base are examining issues such as packet switching and data compression for moving large data files across different media with varying bandwidth. Currently, Eagle Vision brings its own indigenous communications system when it deploys.
Another improvement that defines Eagle Vision IV is its smaller size. The downlink element has been shrunk from a van-sized unit to a box that can be mounted on the back of a high mobility multipurpose wheeled vehicle (HMMWV).
The original Eagle Vision system processed Landsat, Spot and Radarsat data. However, as more national technical assets and commercial platforms entered the picture, planners needed the capability to integrate these different types of data into a product that can be incorporated into a mission planning system.
This requirement led to Joint Eagle, an experiment aimed at combining U.S. and commercial satellite data into the NIMA standard format for exploitation in mission planning. This version, which incorporated the national imagery processing workstation from National Eagle, was deployed just prior to the Kosovo operation from its home site at Ramstein Air Base to the Joint Analysis Center at Royal Air Force (RAF) Molesworth in the United Kingdom.
Col. Clark notes that the NIMA controlled imagery base standard format, known as CIB, allows mosaicking multiple scenes that are radiometrically balanced and orthorectified. Consolidated geospatial imagery can be combined with geographic control to be loaded into a mission planning system complete with digital terrain data for a 3-D flythrough capability.
While NIMA has been able to attain this capability at facilities in the United States, Joint Eagle brought it to the theater. The unit at Molesworth was equipped with every mission planning system from the U.S. European Command to support the 48th Fighter Wing at RAF Lakenheath and the Special Operations Wing at RAF Mildenhall. These planning systems included Topscene, the Air Force Missions Support System (AFMSS), PowerScene and the PFPS.
During the Kosovo conflict, Col. Clark relates that Eagle Vision incorporated 12 Spot and nine Radarsat scenes. Eagle Vision also purchased 24 images of Kosovo from the IRS satellite, which provides 5-meter resolution. Eagle Vision now is being modified to accept IRS data directly.
For the Kosovo air war, Eagle Vision was involved in a program known as Operation Precision Predator. Expertise gleaned from the Joint Eagle experiment was teamed with national geopositioning data to determine accurate coordinates of Predator data quickly. This allowed combined air operations center (CAOC) commanders to locate time-critical targets. Col. Clark notes that this capability also helped commanders call off attacks at the last minute, such as when a tractor carrying refugees pulled up alongside a target. Rather than risk civilian lives, commanders waited until they saw that the refugees had moved before launching strikes against the original target.
Operators in the CAOC in Vincenza could view IRS 5-meter panchromatic data and live Predator imagery along with a rolling map display. Having produced a 1-meter controlled imagery base of all of Kosovo, Eagle Vision locked a Predator’s global positioning system signal into its PowerScene 3-D flythrough. This permitted the CAOC commander to see where the Predator was flying dynamically through Kosovo while simultaneously viewing the UAV’s imagery.
An adjunct to Eagle Vision is Eagle Express, which is a form of NIMA in a Box (SIGNAL, October 1999, page 17) that allows Eagle Vision generated imagery to be shared among different units. Col. Clark notes that the Eagle Vision program is working to install Eagle Express in the PFPS.
The colonel relates that ongoing tests aim at downsizing the PowerScene 3-D flythrough system. The goal is to remove it from the large graphics computers and also place it on the PFPS. This involves installing some of the PowerScene functionality on the mission planning system. “A lot of times, PowerScene would give you a Rolls Royce capability, where all you really required was a Volkswagen Beetle capability,” he explains.
“Look at the joint mission planning system as the television or videocassette recorder at your house,” the colonel analogizes. “Look at PowerScene and NIMA in a Box as HBO or Showtime. Think of Eagle Vision as the fighter pilot’s cable television company. A warfighting commander can channel surf to any satellite that flies into his area of responsibility.”
The U.S. Navy has not purchased Eagle Vision, but it is following the program’s activities, according to Col. Clark. He suggests that one technical hurdle that remains to be overcome is that a shipborne Eagle Vision would have problems maintaining its link with a low-earth-orbit imaging satellite. “I don’t think the state of the art is there yet to stabilize a tracking antenna on a rolling deck,” he offers.
While Eagle Vision has reached agreements with many of the new commercial remote sensing providers, it currently has no plans to incorporate data from Space Imagery. The Colorado firm is generating 1-meter-resolution imagery from its Ikonos satellite, and it plans to orbit a system capable of 0.5-meter resolution. Col. Clark explains that negotiations continue with the company, but both sides must overcome technical hurdles and have yet to agree on a fair market price. Meanwhile, Eagle Vision will be able to incorporate the 2.5-meter-resolution imagery expected from Spot 5 when it is launched next year.