Wullenweber
Encyclopedia
Antenna (radio)
An antenna is an electrical device which converts electric currents into radio waves, and vice versa. It is usually used with a radio transmitter or radio receiver...
array used for radio direction finding. It was used by the military to triangulate
Triangulation
In trigonometry and geometry, triangulation is the process of determining the location of a point by measuring angles to it from known points at either end of a fixed baseline, rather than measuring distances to the point directly...
radio signals for radio navigation, intelligence gathering and search and rescue. Because its huge circular reflecting screen looks like a circular fence, the antenna has been colloquially referred to as the elephant cage. The term wullenwever was the World War II German cover
Cover
- Science and technology :* A covering, usually one that completely closes the object** Lid** Mechanical seal* The outside of an object, not necessarily enclosing the object** Album cover** Book cover, or magazine cover** CD and DVD packaging...
term used to identify their secret CDAA research and development program; its name is unrelated to any person involved in the program.
History
Wullenweber technology was developed by the German navy communication research command, Nachrichtenmittelversuchskommando (NVK) and TelefunkenTelefunken
Telefunken is a German radio and television apparatus company, founded in Berlin in 1903, as a joint venture of Siemens & Halske and the Allgemeine Elektricitäts-Gesellschaft...
during the early years of World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
. The inventor was NVK group leader Dr. Hans Rindfleisch, who worked after the war as a Technical Director for the northern Germany official broadcast ( Norddeutscher Rundfunk - NDR
Norddeutscher Rundfunk
Norddeutscher Rundfunk is a public radio and television broadcaster, based in Hamburg. In addition to the city-state of Hamburg, NDR transmits for the German states of Lower Saxony, Mecklenburg-Vorpommern and Schleswig-Holstein...
). Technical team leaders were Dr. Joachim Pietzner, Dr. Hans Schellhoss, and Dr. Maximilian Wächtler. The latter was a founder of Plath GmbH in 1954 and later a consultant to both Plath and Telefunken.
Dr. Rolf Wundt, a German antenna researcher, was one of hundreds of German scientists taken to the U.S. by the Army after the war under Operation Paperclip
Operation Paperclip
Operation Paperclip was the Office of Strategic Services program used to recruit the scientists of Nazi Germany for employment by the United States in the aftermath of World War II...
. He arrived in New York in March, 1947 on the same ship as Wernher Von Braun
Wernher von Braun
Wernher Magnus Maximilian, Freiherr von Braun was a German rocket scientist, aerospace engineer, space architect, and one of the leading figures in the development of rocket technology in Nazi Germany during World War II and in the United States after that.A former member of the Nazi party,...
and his wife and parents. He was first employed by the U.S. Air Force, then by GT&E Sylvania Electronics Systems on Wullenweber and other antenna projects.
Although the three men retired in West Germany, some of their second-echelon technicians were taken to the USSR after the war. At least 30 Krug (Russian for circle) arrays were installed all over the Soviet Union and allied countries in the 1950s, well before the U.S. military became interested and developed their own CDAAs. Several Krugs were installed in pairs within less than 10 km kilometers of each other, apparently for radio navigation purposes. At least four Krugs were installed near Moscow; just to the north, east and south (55.46408°N 37.3698°E) of the city. The Krugs were used to track the early Sputnik satellites, using their 10 and 20 MHz beacons, and were instrumental in locating re-entry vehicle.
The first Wullenwever was built during the war at Skisby (in German: Hjörring), Denmark (57°28′39"N 10°20′04"E). It used forty vertical radiator elements, placed on the arc of a circle with a diameter of 120 meters. Forty reflecting elements were installed behind the radiator elements, suspended on a circular wooden support structure with a diameter of 112.5 meters. To more easily obtain true geographic bearings, the north and south elements were placed exactly on the North-South meridian. The Soviet Krug arrays also use the 40 radiator Wullenwever configuration.
The array in Skisby was extensively studied by the British, then destroyed following the war in accordance with the Geneva Convention. Dr. Wächtler arranged to have a second array built, at Telefunken expense, at Langenargen/Bodensee, for further experimentation after the war. In the years following the war, the U.S. disassembled the Langenargen/Bodensee array and brought it back to the U.S., where it became known as the "Wullenweber" array.
Professor Edgar Hayden, then a young engineer in the University of Illinois
University of Illinois at Urbana-Champaign
The University of Illinois at Urbana–Champaign is a large public research-intensive university in the state of Illinois, United States. It is the flagship campus of the University of Illinois system...
Radio Direction Finding Research Group, led the reassembly of the Wullenweber, studied the design and performance of HF/DF arrays and researched the physics of HF/DF under contract to the U.S. Navy from 1947 through 1960. His research is still used today to guide the design and site selection of HF/DF arrays. Records of his research are available in the university's archives. Hayden was later employed by Southwest Research Institute
Southwest Research Institute
Southwest Research Institute , headquartered in San Antonio, Texas, is one of the oldest and largest independent, nonprofit, applied research and development organizations in the United States...
where he continued to contribute to HF direction finding technology.
Hayden led the design and development of a large Wullenweber array at the university's Bondville Road Field Station, a few miles southwest of Bondville, IL. The array consisted of a ring 120 vertical monopoles covering 2-20 MHz. Tall wood poles supported a 1000 feet (304.8 m) circular screen of vertical wires located within the ring of monopoles. Due to their immense size, the location of the Bondville array (40.0494°N 88.3807°W) and the other post-war Wullenweber arrays are clearly visible in high resolution aerial photography available on the internet.
In 1959, the U.S. Navy contracted with ITT
ITT Corporation
ITT Corporation is a global diversified manufacturing company based in the United States. ITT participates in global markets including water and fluids management, defense and security, and motion and flow control...
Federal Systems to deploy a worldwide network of AN/FRD-10 HF/DF arrays based on lessons learned from the Bondville experimental array. The FRD-10 at NSGA Hanza, Okinawa was the first installed, in 1962, followed by eleven additional arrays, with the last completed in 1964 at NSGA Imperial Beach, CA. (Silver Strand) A pair of FRD-10s not equipped for HF/DF were installed in 1969 at NAVRADSTA(R) Sugar Grove, WV for naval HF communications, replacing the NSS receiver site at the Naval Communications Station in Cheltenham, MD. The last two FRD-10 HF/DF arrays were installed in 1971 for the Canadian Forces in Gander, Newfoundland and Masset, British Columbia
Masset, British Columbia
Masset , formerly Massett, is a village in Haida Gwaii in British Columbia, Canada. It is located on the northern coast of Graham Island, the largest island in the archipelago, and is approximately west of mainland British Columbia. It is the western terminus of the Yellowhead Highway...
. After the Hanza array was decommissioned in 2006, the Canadians now operate the last two FRD-10 arrays in existence.
Also in 1959, a contract to build a larger Wullenweber array—the AN/FLR-9
AN/FLR-9
The AN/FLR-9 is a type of very large circular "Wullenweber" antenna array, built at many locations during the cold war for HF/DF direction finding of high priority targets. The worldwide network, known collectively as "Iron Horse", could locate HF communications almost anywhere on the planet...
antenna receiving system—was awarded by the U.S. Air Force to GT&E Sylvania Electronics Systems (now General Dynamics
General Dynamics
General Dynamics Corporation is a U.S. defense conglomerate formed by mergers and divestitures, and as of 2008 it is the fifth largest defense contractor in the world. Its headquarters are in West Falls Church , unincorporated Fairfax County, Virginia, in the Falls Church area.The company has...
Advanced Information Systems). The first FLR-9 was installed at RAF Chicksands
RAF Chicksands
RAF Chicksands was a Royal Air Force station in Bedfordshire, England, which closed in 1997 when responsibility for the camp was taken over by the British Army Intelligence Corps...
(52.0443°N 0.389182°W), United Kingdom in 1962. The second FLR-9 was installed at San Vito dei Normanni Air Station, Italy also in 1962. The Chicksands array was dismantled following base closure in 1996 and the San Vito array was dismantled following base closure in 1993.
A second contract was awarded to Sylvania to install AN/FLR-9 systems at Misawa AB, Japan; Clark AB, Philippine Islands; Pakistan (never built); Elmendorf AFB, Alaska; and Karamursel AS, Turkey. The last two were completed in 1966. The Karamursel AS was closed and array was dismantled in 1977 in retribution for the suspension of U.S. military aid to Turkey. The Clark AB array was decommissioned after the Mt. Pinatubo volcano eruption in 1991. It was later converted into an outdoor amphitheater. As of 2007, only the Elmendorf and Misawa arrays remain in service, but both are likely to be decommissioned soon due to their age and unavailability of repair parts.
The U.S. Army awarded a contract in 1968 to F&M Systems to build AN/FLR-9 systems for USASA Field Station Augsburg
USASA Field Station Augsburg
United States Army Security Agency Field Station Augsburg was the site of a Wullenweber AN/FLR-9 radio direction finder, established during the Cold War. Field Station Augsburg was located on Gablingen Kaserne, near the village of Gablingen just north of Augsburg in Bavaria, West Germany. It was...
, Germany and Camp Ramasun in Udon Thani Province
Udon Thani Province
Udon Thani is one of the north-eastern provinces of Thailand. Neighboring provinces are Nong Khai, Sakon Nakhon, Kalasin, Khon Kaen, Nong Bua Lamphu and Loei.- Geography :...
, Thailand. Both were installed in 1970. The Army version has the same design as the Air Force version, but the design of the delay lines in the Beam Forming Networks inside the Central Building are different. The Army used what is called a "Lamp Cluster" delay line design and the Air Force used a "Coaxial" delay line design. The Camp Ramasun array was dismantled in 1975 following base closure. The Augsburg array was turned over to the Bundesnachrichtendienst
Bundesnachrichtendienst
The Bundesnachrichtendienst [ˌbʊndəsˈnaːχʁɪçtnˌdiːnst] is the foreign intelligence agency of Germany, directly subordinated to the Chancellor's Office. Its headquarters are in Pullach near Munich, and Berlin . The BND has 300 locations in Germany and foreign countries...
-- the German Intelligence Service known as the BND—in 1998, and it is no longer believed to be in service.
During the 1970s, the Japanese government installed two large Wullenweber arrays, similar to the FRD-10, at Chitose and Miho.
Later in the 1970s, Plessey
Plessey
The Plessey Company plc was a British-based international electronics, defence and telecommunications company. It originated in 1917, growing and diversifying into electronics. It expanded after the second world war by acquisition of companies and formed overseas companies...
-- now Roke Manor Research Limited
Roke Manor Research Limited
Founded in 1956, Roke Manor Research Limited is a UK company based at Roke Manor in Romsey, Hampshire. It is a contract research and development business for communications, networks, and electronic sensors. In addition to supporting Chemring, work is also conducted in both the public and private...
-- of Great Britain developed their smaller, more economical Pusher CDAA array. At least 25 Pusher CDAAs were installed in many countries around the world. Several Pusher arrays were installed in U.S. military facilities, where the array is known as the AN/FRD-13.
Today, the Strategic Reconnaissance Command of the German Armed Forces
Bundeswehr
The Bundeswehr consists of the unified armed forces of Germany and their civil administration and procurement authorities...
operates a wullenweber array in Bramstedtlund
Bramstedtlund
Bramstedtlund is a municipality in the district of Nordfriesland, in Schleswig-Holstein, Germany....
with a diameter of 410m as one of its three stationary Sigint
SIGINT
Signals intelligence is intelligence-gathering by interception of signals, whether between people , whether involving electronic signals not directly used in communication , or combinations of the two...
battalions.
See also
- HF/DF
- Radio direction finderRadio direction finderA radio direction finder is a device for finding the direction to a radio source. Due to low frequency propagation characteristic to travel very long distances and "over the horizon", it makes a particularly good navigation system for ships, small boats, and aircraft that might be some distance...
- Radio direction finding
- Direction findingDirection findingDirection finding refers to the establishment of the direction from which a received signal was transmitted. This can refer to radio or other forms of wireless communication...
- AN/FLR-9AN/FLR-9The AN/FLR-9 is a type of very large circular "Wullenweber" antenna array, built at many locations during the cold war for HF/DF direction finding of high priority targets. The worldwide network, known collectively as "Iron Horse", could locate HF communications almost anywhere on the planet...
, a Wullenweber-class antenna array - SIGINTSIGINTSignals intelligence is intelligence-gathering by interception of signals, whether between people , whether involving electronic signals not directly used in communication , or combinations of the two...
- Silver Strand Training ComplexSilver Strand Training ComplexSilver Strand Training Complex , formerly known as the Naval Radio Receiving Facility , is the premier training facility for U.S. Special Operations Forces...
External links
- Description and Photographs of the first Wullenwever array in Skisby, Denmark
- Aspects of the German Naval Communications Research Establishment
- Wullenweber/CDDA Antenna Homepage
- Aerial photographs of Krug arrays
- Aerials photographs of FRD-10 arrays
- Aerial photographs of AN/FLR-9 arrays
- Satellite view of Misawa AFB, Japan antenna