 Germany’s SAR-Lupe constellation puts Europe aheadBy Chris Pocock
November 06, 2006
While the U.S. is still defining its Space Radar, a German satellite system that provides high-resolution radar images to European military commanders will soon begin operations. The first of five SAR-Lupe satellites is due to be launched in December by a Russian Cosmos 3M booster.
SAR stands for Synthetic Aperture Radar, and Lupe is the German word for a magnifying glass. Germany committed to the project at the NATO Summit in Prague in 2000, which identified shortcomings in the alliance’s operational capabilities, and enjoined the European members to do something about it. Work on the system began in January 2002 after the German Federal Office for Defense Technology and Procurement (BWB) awarded a 300 million euro ($230 million) contract to OHB-System of Bremen.
OHB’s expertise in small satellites for earth observation and communications helped it clinch the role of prime contractor on SAR-Lupe. But the winning team also comprised key partners in the European aerospace industry. Although prompted by NATO, the SAR-Lupe project is now billed as a key part of Europe’s quest to achieve key independencies in space.
A major attraction of SAR coverage is that the earth’s surface may be imaged at night and through clouds. Until recently, only the U.S. produced high-resolution radar satellites for intelligence-gathering purposes. Three of these large, expensive systems are in orbit, and they remain highly classified. Built by Lockheed Martin in Denver for the National Reconnaissance Office, they are tagged “Lacrosse” in the open literature, which may not be their current codename.
Japan and Russia launched military radar satellites in 2003 and 2004 respectively. And Canada’s Radarsat 2 promises to make radar images at 3-meter resolution in C-band available on a commercial basis after it is launched next March.
But SAR-Lupe will image in X-band and offer a spatial resolution that is “significantly less than 1 meter,” according to Fritz Merkle, the program director at OHB-System. Other sources suggest that the resolution of SAR-Lupe in the “spot” mode will be about 0.5 meter. To produce these 5.5-square-kilometer scenes, the satellite bus is rotated along track by reaction wheels and magnetic torquers so that the fixed antenna can dwell on the area of interest and increase the integration time. In the alternative “strip” mode, the new German satellites will provide a much larger cross-track image of 60 kilometers by 8 kilometers, at a resolution of 1 meter.
Moreover, because there will eventually be five satellites in the constellation and they can receive tasking and transmit imagery via other satellites, the response time should be better than previous space systems. The contract calls for images to be received at the ground station less than 36 hours after tasking, and less than 12 hours after being taken. In fact, Merkle told C4ISR Journal that the average time between tasking and receipt of a processed image should be 10 hours. More than 30 images can be produced each day, across the globe, from 80 degrees north to 80 degrees south.
The SAR-Lupe satellite’s parabolic antenna has a 10-foot diameter and is used for both image acquisition and transmission, although not simultaneously. It also serves as the receiver for uplinked commands (in S-band). All communications are encrypted. The satellites will be placed in polar low-earth orbits, in three orbital planes (two satellites each in two planes, and one satellite in the third plane). The constellation should be complete by mid-2008.
SAR-Lupe was the first “smart procurement” by the BWB and could be the first military space imaging system to be procured under such terms. OHB-System was given functional requirements and performance goals only. Merkle said the BWB wanted the highest possible resolution and the shortest possible revisit rates.
When the fixed-price contract was signed, OHB’s chief executive officer Manfred Fuchs said the goals would be met by “an intelligent combination of already existing and proven components.” Of note, OHB decided against using the latest electronically steered antennas. Merkle explained that they require too much power to produce high-resolution imagery from space. The 15-year contract includes a 10-year in-service warranty.
The first hardware test took place in November 2002 on what OHB describes as the “particularly powerful” radar transmitter tube. The critical design review followed shortly. By late 2003, the engineering test model was coming together in OHB’s purpose-built integration facility in Bremen, which includes a radome. In a unique ground test in October 2004, coordinates for the International Space Station in orbit were fed to the satellite, which made the appropriate alignment and took a high-resolution image through the radome. In January 2005, the enlarged fairing that houses the parabolic antenna was flight-tested in a launch of an unrelated payload by a Cosmos launcher.
But the schedule was slipping, and although the first two flight satellites were being integrated in mid-2005, the plan to launch that year was postponed.
“It was always recognized that the original schedule was challenging,” Merkle said.
Part of the delay was caused by concerns about the satellite’s security system. The BWB requested and paid for an upgrade to the authentication and encryption hardware and software.
In the meantime, OHB commissioned the Satellite Ground Segment at Gelsdorf near Bonn. The company will operate this facility to control the satellites in orbit and receive the raw radar data. The processed data will then be transferred to a user ground segment for exploitation, dissemination and archiving. This second ground station will be co-located but operated by German military personnel.
France and Germany signed a mutual access agreement for military space reconnaissance in 2002. The ground segments for SAR-Lupe and the French Helios II satellite will be linked, so that each country can task the other’s satellite and receive imagery. Helios II is an improved version of an electro-optic system that first went into orbit in 1995. It offers submeter resolution and infrared coverage. The first of two satellites was launched in December 2004.
This cooperation is billed by OHB as “the core element of a Europe-wide strategic reconnaissance system.” But the company is still awaiting a go-ahead to implement interoperability between SAR-Lupe and Helios, which could, therefore, still be two years away. Belgium, Italy and Spain already have minority stakes in Helios and are reported to have negotiated with the German government to join SAR-Lupe. OHB has proposed extending the constellation with four additional satellites that would be owned by other countries.
The European Union already operates a Satellite Centre at Torrejon air base near Madrid, Spain, where image analysts from various countries work on a variety of products, mainly commercial satellite imagery (CSI). The availability of high-resolution CSI from multiple providers has blurred the distinction between military and commercial space systems. The next generation of European CSI systems, such as Pleiades led by France (the successor to SPOT), and COSMO-SkyMed, an Italian radar-imaging satellite, will clearly be dual-use.
Ironically, the German government is part-funding a commercial space radar-imaging system that is more advanced than SAR-Lupe in one respect. The TerraSAR-X satellite built by a partnership comprising EADS Atrium and the German Aerospace Center (DLR) has an active antenna. It was due for launch Oct. 31 and will offer 1-meter to 2-meter resolution. “But no one else has the bandwidth of SAR-Lupe,” Merkle said.
Indeed, spatial resolution is not the only consideration. If an imaging satellite system is to have real military utility, it must be reliable and timely. OHB says that two or three SAR-Lupe satellites can meet the BWB’s stated requirements; having five of them in orbit reduces the performance risk.
“A submetric SAR with rapid delivery will be an extremely potent provider,” said Geoffrey Quick, an imagery analyst and consultant. Furthermore, the SAR-Lupe system will be capable of producing stereo-interferometric SAR from multiple passes, to produce terrain elevation data. However, Merkel said, most requirements for elevation data can be met by other space systems, including a follow-on version of TerraSAR.
The quest for timeliness has complicated the U.S. drive to implement global radar-reconnaissance from space. As originally conceived in the late 1990s, the Discoverer II system would have comprised 24 satellites and was billed as offering a surveillance-to-strike time of less than 15 minutes. It was soon judged unaffordable. Now, the renamed Space Radar system seems likely to comprise nine satellites, with the resulting gaps in coverage filled by airborne ISR assets such as the Global Hawk UAV.
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2001 article
Report: German Army No Longer Uses Microsoft Programs
Due to the fear that they may be spied upon by US secret services, the German Foreign Office and the German army want to seal all security gaps, according to the current edition of the news magazine Der Spiegel.
The German army will no longer use any Microsoft software in computers that are used in sensitive areas. According to findings by German security authorities, the US National Security Agency (NSA) has access to all pertinent Microsoft source code and can thus read even encrypted data.
To protect secrets, the German Ministry of Defense now uses encryption technology from the German firms Siemens and Telekom.
Germany's Foreign Office has also postponed plans to introduce video conferences with its foreign representatives. During a Telekom presentation in Berlin at the start of March, State Secretary Gunter Pleuger found out that, for technical reasons, all satellite transmissions travel by way of the American city Denver, in Colorado.
This detour through the USA was too uncertain for Pleuger. "We may as well just hold our conferences in Langley," joked one of Pleuger's co-workers. Langley, Va.,is the home of the American secret service, the CIA.
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As you probably already noted, this article is of november, 2006. But what the matter is the information that contains and will be important to understand the importance of the launch of the second satellite on 1st july.
Since i will not be here by that time, i decided to submit the article a few days earlier.
The article is long, so i recommend you to read what is at bold first, i've highlighted what i consider more important.
Europe is building a military space network that is independent of US. This is extremely important because denounces what is the level of trust between them.
If these european moves are source for preoccupation for Washington, the fact that Europe selects Russia to put them in space, means that Europe doesn't trust US to deliver them and instead shows a high level of trust between France, Germany and Russia. Better saying the "Old Europe" and Russia.
Russia is launching from Plesetsk where they launch their military satellites, and it is interesting to see, that they are using too for Europe military needs.
As you can see, this news shows that despite the "great" friendship between Europe and US, the truth is, Europe doesn't trust US and shows a growing friendship (not referred in media) with Russia that must be causing some heart attacks on Washington.
Regarding the level of trust between Europe and US, i strong recommend the lecture of the second article.
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