Earth station
Encyclopedia
Terminal (telecommunication)
In the context of telecommunications, a terminal is a device which is capable of communicating over a line. Examples of terminals are telephones, fax machines, and network devices - printers and workstations....
station designed for extraplanetary telecommunication
Telecommunication
Telecommunication is the transmission of information over significant distances to communicate. In earlier times, telecommunications involved the use of visual signals, such as beacons, smoke signals, semaphore telegraphs, signal flags, and optical heliographs, or audio messages via coded...
with spacecraft
Spacecraft
A spacecraft or spaceship is a craft or machine designed for spaceflight. Spacecraft are used for a variety of purposes, including communications, earth observation, meteorology, navigation, planetary exploration and transportation of humans and cargo....
, and/or reception of radio waves
Radio waves
Radio waves are a type of electromagnetic radiation with wavelengths in the electromagnetic spectrum longer than infrared light. Radio waves have frequencies from 300 GHz to as low as 3 kHz, and corresponding wavelengths from 1 millimeter to 100 kilometers. Like all other electromagnetic waves,...
from an astronomical radio source. Ground stations are located either on the surface of the Earth, or within Earth's atmosphere
Earth's atmosphere
The atmosphere of Earth is a layer of gases surrounding the planet Earth that is retained by Earth's gravity. The atmosphere protects life on Earth by absorbing ultraviolet solar radiation, warming the surface through heat retention , and reducing temperature extremes between day and night...
. Earth stations communicate with spacecraft by transmitting and receiving radio waves in the super high frequency
Super high frequency
Super high frequency refers to radio frequencies in the range of 3 GHz and 30 GHz. This band of frequencies is also known as the centimetre band or centimetre wave as the wavelengths range from ten to one centimetres....
or extremely high frequency
Extremely high frequency
Extremely high frequency is the highest radio frequency band. EHF runs the range of frequencies from 30 to 300 gigahertz, above which electromagnetic radiation is considered to be low infrared light, also referred to as terahertz radiation...
bands (e.g., microwave
Microwave
Microwaves, a subset of radio waves, have wavelengths ranging from as long as one meter to as short as one millimeter, or equivalently, with frequencies between 300 MHz and 300 GHz. This broad definition includes both UHF and EHF , and various sources use different boundaries...
s). When a ground station successfully transmits radio waves to a spacecraft (or vice versa), it establishes a telecommunications link.
Ground stations may occupy either a fixed or itinerant position. Article 1 § III of the ITU
International Telecommunication Union
The International Telecommunication Union is the specialized agency of the United Nations which is responsible for information and communication technologies...
Radio Regulations describes various types of stationary and mobile ground stations, and their interrelationships.
Specialized satellite earth stations are used to telecommunicate with satellite
Satellite
In the context of spaceflight, a satellite is an object which has been placed into orbit by human endeavour. Such objects are sometimes called artificial satellites to distinguish them from natural satellites such as the Moon....
s—chiefly communications satellite
Communications satellite
A communications satellite is an artificial satellite stationed in space for the purpose of telecommunications...
s. Other ground stations communicate with manned space station
Space station
A space station is a spacecraft capable of supporting a crew which is designed to remain in space for an extended period of time, and to which other spacecraft can dock. A space station is distinguished from other spacecraft used for human spaceflight by its lack of major propulsion or landing...
s or unmanned space probe
Space probe
A robotic spacecraft is a spacecraft with no humans on board, that is usually under telerobotic control. A robotic spacecraft designed to make scientific research measurements is often called a space probe. Many space missions are more suited to telerobotic rather than crewed operation, due to...
s. A ground station that primarily receives telemetry
Telemetry
Telemetry is a technology that allows measurements to be made at a distance, usually via radio wave transmission and reception of the information. The word is derived from Greek roots: tele = remote, and metron = measure...
data, or that follows a satellite not in geostationary orbit
Geostationary orbit
A geostationary orbit is a geosynchronous orbit directly above the Earth's equator , with a period equal to the Earth's rotational period and an orbital eccentricity of approximately zero. An object in a geostationary orbit appears motionless, at a fixed position in the sky, to ground observers...
, is called a tracking station.
When a satellite is within a ground station's line of sight, the station is said to have a view of the satellite. It is possible for a satellite to communicate with more than one ground station at a time. A pair of ground stations are said to have a satellite in mutual view when the stations share simultaneous, unobstructed, line-of-sight contact
Line-of-sight propagation
Line-of-sight propagation refers to electro-magnetic radiation or acoustic wave propagation. Electromagnetic transmission includes light emissions traveling in a straight line...
with the satellite.
Telecommunications port
A telecommunications port—or, more commonly, teleport—is a satellite ground station with multiple parabolic antennaParabolic antenna
A parabolic antenna is an antenna that uses a parabolic reflector, a curved surface with the cross-sectional shape of a parabola, to direct the radio waves. The most common form is shaped like a dish and is popularly called a dish antenna or parabolic dish...
s (i.e., an antenna farm
Antenna farm
Antenna farm or satellite dish farm or just dish farm are terms used to describe an area dedicated to television or radio telecommunications transmitting or receiving antenna equipment, such as C, Ku or Ka band satellite dish antennas, UHF/VHF/AM/FM transmitter towers or mobile cell towers.In...
) that functions as a hub connecting a satellite or geocentric orbit
Geocentric orbit
A geocentric orbit involves any object orbiting the Earth, such as the Moon or artificial satellites. Currently there are approximately 2,465 artificial satellites orbiting the Earth and 6,216 pieces of space debris as tracked by the Goddard Space Flight Center...
al network with a terrestrial telecommunications network
Telecommunications network
A telecommunications network is a collection of terminals, links and nodes which connect together to enable telecommunication between users of the terminals. Networks may use circuit switching or message switching. Each terminal in the network must have a unique address so messages or connections...
.
Teleports may provide various broadcasting
Broadcasting
Broadcasting is the distribution of audio and video content to a dispersed audience via any audio visual medium. Receiving parties may include the general public or a relatively large subset of thereof...
services among other telecommunications functions, such as uploading
Uploading and downloading
In computer networks, to download means to receive data to a local system from a remote system, or to initiate such a data transfer. Examples of a remote system from which a download might be performed include a webserver, FTP server, email server, or other similar systems...
computer program
Computer program
A computer program is a sequence of instructions written to perform a specified task with a computer. A computer requires programs to function, typically executing the program's instructions in a central processor. The program has an executable form that the computer can use directly to execute...
s or issuing commands
Command (computing)
In computing, a command is a directive to a computer program acting as an interpreter of some kind, in order to perform a specific task. Most commonly a command is a directive to some kind of command line interface, such as a shell....
over an uplink to a satellite.
Earth terminal complexes
In Federal Standard 1037CFederal Standard 1037C
Federal Standard 1037C, titled Telecommunications: Glossary of Telecommunication Terms is a United States Federal Standard, issued by the General Services Administration pursuant to the Federal Property and Administrative Services Act of 1949, as amended....
, the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
General Services Administration
General Services Administration
The General Services Administration is an independent agency of the United States government, established in 1949 to help manage and support the basic functioning of federal agencies. The GSA supplies products and communications for U.S...
defined an earth terminal complex as the assemblage of equipment and facilities necessary to integrate an earth terminal (ground station) into a telecommunications network. FS-1037C has since been subsumed by the ATIS Telecom Glossary, which is maintained by the Alliance for Telecommunications Industry Solutions
Alliance for Telecommunications Industry Solutions
The Alliance for Telecommunications Industry Solutions is a standards organization that develops technical and operational standards for the telecommunication industry. ATIS is headquartered in Washington, D.C....
, an international, business-oriented, non-governmental organization
Non-governmental organization
A non-governmental organization is a legally constituted organization created by natural or legal persons that operates independently from any government. The term originated from the United Nations , and is normally used to refer to organizations that do not form part of the government and are...
. The Telecommunications Industry Association
Telecommunications Industry Association
The Telecommunications Industry Association is accredited by the American National Standards Institute to develop voluntary, consensus-based industry standards for a wide variety of ICT products, and currently represents nearly 400 companies...
also acknowledges this definition.
Satellite communications standards
The ITU Radiocommunication SectorITU-R
The ITU Radiocommunication Sector is one of the three sectors of the International Telecommunication Union and is responsible for radio communication....
(ITU-R), a division of the International Telecommunication Union
International Telecommunication Union
The International Telecommunication Union is the specialized agency of the United Nations which is responsible for information and communication technologies...
, codifies international standards agreed-upon through multinational discourse. From 1927 to 1932, standards and regulations now governed by the ITU-R were administered by the International Consultative Committee for Radio.
In addition to the body of standards defined by the ITU-R, each major satellite operator provides technical requirements and standards that ground stations must meet in order to communicate with the operator's satellites. For example, Intelsat
Intelsat
Intelsat, Ltd. is a communications satellite services provider.Originally formed as International Telecommunications Satellite Organization , it was—from 1964 to 2001—an intergovernmental consortium owning and managing a constellation of communications satellites providing international broadcast...
publishes the Intelsat Earth Station Standards (IESS) which, among other things, classifies ground stations by the capabilities of their parabolic antennas, and pre-approves certain antenna models. Eutelsat
Eutelsat
Eutelsat S.A. is a French-based satellite provider. Providing coverage over the entire European continent, as well as the Middle East, Africa, India and significant parts of Asia and the Americas, it is one of the world's three leading satellite operators in terms of revenues.Eutelsat’s satellites...
publishes similar standards and requirements, such as the Eutelsat Earth Station Standards (EESS).
See also
- Fundamental stationFundamental stationA fundamental point is the geometric origin of a geodetic network and defines the geodetic datum of a national survey.Some fundamental stations are an astronomical or satellite geodetic observatory...
- Geosynchronous orbitGeosynchronous orbitA geosynchronous orbit is an orbit around the Earth with an orbital period that matches the Earth's sidereal rotation period...
- List of astronomical observatories
- ObservatoryObservatoryAn observatory is a location used for observing terrestrial or celestial events. Astronomy, climatology/meteorology, geology, oceanography and volcanology are examples of disciplines for which observatories have been constructed...
- Radio astronomyRadio astronomyRadio astronomy is a subfield of astronomy that studies celestial objects at radio frequencies. The initial detection of radio waves from an astronomical object was made in the 1930s, when Karl Jansky observed radiation coming from the Milky Way. Subsequent observations have identified a number of...
- Radio telescopeRadio telescopeA radio telescope is a form of directional radio antenna used in radio astronomy. The same types of antennas are also used in tracking and collecting data from satellites and space probes...
Major earth stations and earth terminal complexes
- Bukit Timah Satellite Earth StationBukit Timah Satellite Earth StationThe Bukit Timah Satellite Earth Station is the second satellite earth station in Singapore after Sentosa Satellite Earth Station in Sentosa Island. The station is located in Bukit Timah near Chantek flyover between Bukit Timah Expressway and Pan Island Expressway...
- Canberra Deep Space Communication ComplexCanberra Deep Space Communication ComplexThe Canberra Deep Space Communication Complex is a ground station that is located in Australia at Tidbinbilla in the Paddys River valley, about half an hour's drive out of Canberra in the Australian Capital Territory. The complex is part of the Deep Space Network run by NASA's Jet Propulsion...
- Goldstone Deep Space Communications ComplexGoldstone Deep Space Communications ComplexThe Goldstone Deep Space Communications Complex — commonly called the Goldstone Observatory — is located in California's Mojave Desert. Operated by ITT Corporation for the Jet Propulsion Laboratory, its main purpose is to track and communicate with space missions. It includes the Pioneer...
- Goonhilly Satellite Earth StationGoonhilly Satellite Earth StationGoonhilly Satellite Earth Station is a large telecommunications site located on Goonhilly Downs near Helston on the Lizard peninsula in Cornwall, England, UK. Owned by BT Group plc, it was at one time the largest satellite earth station in the world, with more than 25 communications dishes in use...
- Honeysuckle Creek Tracking StationHoneysuckle Creek Tracking StationHoneysuckle Creek was a NASA tracking station near Canberra, Australia, which played an important role in supporting Project Apollo. The station was opened in 1967 and closed in 1981....
- Kaena Point Satellite Tracking StationKaena Point Satellite Tracking StationThe Kaena Point Satellite Tracking Station is a United States Air Force military installation in Kaena Point on the island of Oahu in Hawaii. It is a remote tracking station of the Air Force Satellite Control Network responsible for tracking satellites in orbit, many of which support the United...
- Madley Communications CentreMadley Communications CentreMadley Communications Centre is British Telecom's earth satellite tracking station, between Madley and Kingstone, Herefordshire, England. It claims to be the largest earth station in the world.-Earth position:...
- Madrid Deep Space Communication ComplexMadrid Deep Space Communication ComplexThe Madrid Deep Space Communications Complex is a ground station located in Robledo de Chavela, Spain, and operated by Ingenieria y Servicios Aeroespaciales, S.A. for Instituto Nacional de Técnica Aeroespacial.-Deep Space Network:...
- Suparco Satellite CenterSUPARCO Satellite Ground StationThe SUPARCO Satellite Ground Station is an earth observation and remote sensing satellite control center. The SUPARCO's SGS center is a major space research centre of the Space and Upper Atmosphere Research Commission , focusing on the earth observational and remote sensing technology.The space...
External links
- UplinkStation.com, a corporate directory of commercial teleports, satellite televisionSatellite televisionSatellite television is television programming delivered by the means of communications satellite and received by an outdoor antenna, usually a parabolic mirror generally referred to as a satellite dish, and as far as household usage is concerned, a satellite receiver either in the form of an...
operators, et al. Accessed on 22 April 2009. - World Teleport Association Accessed on 22 April 2009.