OMEGA was the first truly global
radio navigationRadio navigation or radionavigation is the application of radio frequencies to determine a position on the Earth. Like radiolocation, it is a type of radiodetermination.The basic principles are measurements from/to electric beacons, especially...
system for aircraft, operated by the
United StatesThe United States of America is a federal constitutional republic comprising fifty states and a federal district...
in cooperation with six partner nations.
History
OMEGA was originally developed by the
United States NavyThe United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...
for military aviation users. It was approved for development in 1968 with only eight transmitters and the ability to achieve a four mile (6 km) accuracy when fixing a position. Each Omega station transmitted a very low frequency signal which consisted a tone/duration unique to the station that was repeated every ten seconds. By comparing the phases of received signals, and radionavigation principles, an accurate fix of the receiver's position could be calculated. OMEGA employed
hyperbolicIn mathematics, hyperbolic geometry is a non-Euclidean geometry, meaning that the parallel postulate of Euclidean geometry is replaced...
radionavigation techniques and the chain operated in the VLF portion of the spectrum between 10 to 14
kHzThe hertz is the SI unit of frequency defined as the number of cycles per second of a periodic phenomenon. One of its most common uses is the description of the sine wave, particularly those used in radio and audio applications....
. Near its end, it evolved into a system used primarily by the civil community. By receiving signals from three stations, an Omega receiver could locate a position to within 4 nautical miles (7.4 km) using the principle of phase comparison of signals.
http://www.jproc.ca/hyperbolic/omega.html
Omega stations used very extensive antennas in order to transmit their extremely low frequencies. They used grounded or insulated guyed masts with umbrella antennas, or wire-spans across fjords. Some Omega antennas were the tallest constructions on the continent where they stood or still stand.
When six of the eight station chain became operational in 1971, day-to-day operations were managed by the
United States Coast GuardThe United States Coast Guard is a branch of the United States Armed Forces and one of the seven U.S. uniformed services. The Coast Guard is a maritime, military, multi-mission service unique among the military branches for having a maritime law enforcement mission and a federal regulatory agency...
in partnership with
ArgentinaArgentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...
,
NorwayNorway , officially the Kingdom of Norway, is a Nordic unitary constitutional monarchy whose territory comprises the western portion of the Scandinavian Peninsula, Jan Mayen, and the Arctic archipelago of Svalbard and Bouvet Island. Norway has a total area of and a population of about 4.9 million...
,
LiberiaLiberia , officially the Republic of Liberia, is a country in West Africa. It is bordered by Sierra Leone on the west, Guinea on the north and Côte d'Ivoire on the east. Liberia's coastline is composed of mostly mangrove forests while the more sparsely populated inland consists of forests that open...
, and
FranceThe French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
. The
JapanJapan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
ese and
AustraliaAustralia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
n stations became operational several years later. Coast Guard personnel operated two US stations: one in
LaMoureAs of the census of 2000, there were 944 people, 386 households, and 238 families residing in the city. The population density was 736.2 people per square mile . There were 433 housing units at an average density of 337.7 per square mile . The racial makeup of the city was 99.15% White, 0.42%...
,
North DakotaNorth Dakota is a state located in the Midwestern region of the United States of America, along the Canadian border. The state is bordered by Canada to the north, Minnesota to the east, South Dakota to the south and Montana to the west. North Dakota is the 19th-largest state by area in the U.S....
and the other in Kaneohe,
HawaiiHawaii is the newest of the 50 U.S. states , and is the only U.S. state made up entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean, southwest of the continental United States, southeast of Japan, and northeast of...
on the island of
OahuOahu or Oahu , known as "The Gathering Place", is the third largest of the Hawaiian Islands and most populous of the islands in the U.S. state of Hawaii. The state capital Honolulu is located on the southeast coast...
.
Due to the success of the
Global Positioning SystemThe Global Positioning System is a space-based global navigation satellite system that provides location and time information in all weather, anywhere on or near the Earth, where there is an unobstructed line of sight to four or more GPS satellites...
the use of Omega declined during the 1990s, to a point where the cost of operating Omega could no longer be justified. Omega was permanently terminated on September 30, 1997 and all stations ceased operation. Several of the towers were then soon demolished.
Some of the stations, such as the LaMoure station, are now used for
submarine communicationsCommunication with submarines is difficult because radio waves do not travel well through thick electrical conductors like salt water.The obvious solution is to surface and raise an antenna above the water, then use ordinary radio transmissions. Early submarines had to frequently surface anyway for...
.
OMEGA stations
There were nine Omega stations in total:
Bratland Omega Transmitter
Bratland Omega Transmitter (station A - 66.42083333°N 13.15055556°E) situated near
AldraAldra is a Norwegian island, close to Bratland, not far from Mo i Rana in Nordland.Aldra island is used as a VLF-transmission site. An antenna, spanning the fjord to Bratland, was used as part of the OMEGA Navigation System until 1997, and was dismantled in 2002.-External links:*...
was the only European Omega transmitter. It used a very unusual antenna, which consisted of several wires spun over a fjord between two concrete anchor blocks 3500 metres apart, one situated at 66°25′27"N 13°10′1"E and 66°24′53"N 13°05′19"E. One of these blocks was situated on the mainland of Norway and the other on
AldraAldra is a Norwegian island, close to Bratland, not far from Mo i Rana in Nordland.Aldra island is used as a VLF-transmission site. An antenna, spanning the fjord to Bratland, was used as part of the OMEGA Navigation System until 1997, and was dismantled in 2002.-External links:*...
island. The antenna was dismantled in 2002.
Trinidad Omega Transmitter
Trinidad Omega Transmitter (station B until 1976, replaced by station in Paynesville, Liberia) situated in
TrinidadTrinidad is the larger and more populous of the two major islands and numerous landforms which make up the island nation of Trinidad and Tobago. It is the southernmost island in the Caribbean and lies just off the northeastern coast of Venezuela. With an area of it is also the fifth largest in...
(at 10.69938°N 61.638708°W) used as antenna a wire span over a valley. Its buildings are still there.
Paynesville Omega Transmitter
La Moure Omega Transmitter (station D) situated near La Moure, North Dakota, USA at 46.365944°N 98.335617°W) was the other station operated by the USCG. It used a 365.25 metre tall
guyed mastA guyed mast is a tall thin vertical structure that receives support from guy lines.Guyed masts are frequently used for radio masts. The mast can either support aerials mounted at its top, or the entire structure itself can function as an antenna ; this is called a mast radiator...
as an antenna, which is insulated against ground. Since the shutdown of the Omega Navigation System, it is used for VLF transmissions to
submarineA submarine is a watercraft capable of independent operation below the surface of the water. It differs from a submersible, which has more limited underwater capability...
s.
Chabrier Omega Transmitter
Chabrier Omega Transmitter (station E ) near Chabrier on
RéunionRéunion is a French island with a population of about 800,000 located in the Indian Ocean, east of Madagascar, about south west of Mauritius, the nearest island.Administratively, Réunion is one of the overseas departments of France...
at 20.974139°S 55.289894°E) used an umbrella antenna, which was installed on a 428-metre tall grounded
guyed mastA guyed mast is a tall thin vertical structure that receives support from guy lines.Guyed masts are frequently used for radio masts. The mast can either support aerials mounted at its top, or the entire structure itself can function as an antenna ; this is called a mast radiator...
. The mast was demolished on April 14, 1999 by explosives.
Woodside Omega Transmitter
Station G, near Woodside, Victoria, Australia,
Omega Tower, Tsushima
Shushi-Wan Omega Transmitter (station H) situated near Shushi-Wan on
Tsushima IslandTsushima Island is an island of the Japanese Archipelago situated in the middle of the Tsushima Strait at 34°25'N and 129°20'E. The main island of Tsushima was once a single island, but the island was divided into two in 1671 by the Ōfunakosiseto canal and into three in 1900 by the Manzekiseto canal...
at 34.614739°N 129.453644°E) used as its antenna, a 389-metre tall tubular steel mast, insulated against ground. This mast, which was built in 1973 and which was the tallest structure in Japan (and perhaps the tallest tubular steel mast ever built) was dismantled in 1998 by crane. On its former site, an approximately 8 metre-tall memorial consisting of the mast base (without the insulator) and a segment was built. On the site of the former helix building there is now a playground.
OMEGA test locations
In addition to the nine operational Omega towers, the tower at
Forestport, NYForestport is a town in Oneida County, New York, United States. The population was 1,692 at the 2000 census.The Town of Forestport is located in the northeast corner of Oneida County...
was used for early testing of the system.
See also
- Alpha
Alpha is a Russian system for long range radio navigation. RSDN in Russian stands for , i.e., radio-technical long-distance navigation system....
, the Russian counterpart of the Omega Navigation System, still in use .
- Decca Navigator
- LORAN
LORAN is a terrestrial radio navigation system using low frequency radio transmitters in multiple deployment to determine the location and speed of the receiver....
, low frequency terrestrial radio navigation system, still in use (US and Canadian operations terminated 2010).
- CHAYKA
Chayka is a Russian terrestrial radio navigation system, similar to LORAN-C. It is also run on 100 kHz and is described like LORAN-C by its GRI.-Chayka-Chains:There are 5 Chayka-chains in use:...
, the Russian counterpart of LORAN
- SHORAN
SHORAN is an acronym for SHOrt RAnge Navigation, a type of electronic navigation and bombing system with a precision radar beacon used in the B-26 and B-29 bomber aircraft during the Korean War.-Origin:...
- Oboe (navigation)
Oboe was a British aerial blind bombing targeting system in World War II, based on radio transponder technology. Oboe accurately measured the distance to an aircraft, and gave the pilot guidance on whether or not they were flying along a pre-selected circular route. The route was only 35 yards...
- G-H (navigation)
Gee-H, or sometimes G-H, was a radio navigation system developed by Britain during World War II to aid RAF Bomber Command. Its official name was AMES Type 100...
- GEE (navigation)
Gee was the code name given to a radio navigation system used by the Royal Air Force during World War II.Different sources record the name as GEE or Gee. The naming supposedly comes from "Grid", so the lower case form is more correct, and is the form used in Drippy's publications. See Drippy 1946....
External links