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43-595: The Canberra Deep Space Communication Complex ( CDSCC ) is a satellite communication station , part of the Deep Space Network of NASA 's Jet Propulsion Laboratory (JPL), located at Tidbinbilla in the Australian Capital Territory . Opened in 1965, the complex was used for tracking the Apollo Lunar Module , and along with its two sister stations at Goldstone, California and Madrid, Spain

86-416: A Telecommunications Satellite Park ) innovation was conceived and developed by Joseph Milano in 1976 as part of a National Research Council study entitled, Telecommunications for Metropolitan Areas: Near-Term Needs and Opportunities". A network of ground stations is a group of stations located to support spacecraft communication, tracking, or both. A network is established to provide dedicated support to

129-560: A letter to the editor of Wireless Engineer in 1942. For example, the approximate geometric mean of band 7 is 10 MHz, or 10  Hz. The band name "tremendously low frequency" (TLF) has been used for frequencies from 1–3 Hz (wavelengths from 300,000–100,000 km), but the term has not been defined by the ITU. Frequency bands in the microwave range are designated by letters. This convention began around World War II with military designations for frequencies used in radar , which

172-483: A move to 2.4 GHz spread spectrum RC control systems. Licensed amateur radio operators use portions of the 6-meter band in North America. Industrial remote control of cranes or railway locomotives use assigned frequencies that vary by area. Radar applications use relatively high power pulse transmitters and sensitive receivers, so radar is operated on bands not used for other purposes. Most radar bands are in

215-571: A satellite. In May 1984, the Dallas/Fort Worth Teleport became the first American teleport to commence operation. In Federal Standard 1037C , the United States General Services Administration 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

258-716: A specific mission, function, program or organization. Ground station networks include: Other historical networks have included: Band (radio) Different parts of the radio spectrum are allocated by the ITU for different radio transmission technologies and applications; some 40 radiocommunication services are defined in the ITU's Radio Regulations (RR). In some cases, parts of the radio spectrum are sold or licensed to operators of private radio transmission services (for example, cellular telephone operators or broadcast television stations). Ranges of allocated frequencies are often referred to by their provisioned use (for example, cellular spectrum or television spectrum). Because it

301-407: A traditional name. For example, the term high frequency (HF) designates the wavelength range from 100 to 10 metres, corresponding to a frequency range of 3 to 30 MHz. This is just a symbol and is not related to allocation; the ITU further divides each band into subbands allocated to different services. Above 300 GHz, the absorption of electromagnetic radiation by Earth's atmosphere

344-431: Is a fixed resource which is in demand by an increasing number of users, the radio spectrum has become increasingly congested in recent decades, and the need to utilize it more effectively is driving modern telecommunications innovations such as trunked radio systems , spread spectrum , ultra-wideband , frequency reuse , dynamic spectrum management , frequency pooling, and cognitive radio . The frequency boundaries of

387-420: Is a small frequency band (a contiguous section of the range of the radio spectrum) in which channels are usually used or set aside for the same purpose. To prevent interference and allow for efficient use of the radio spectrum, similar services are allocated in bands. For example, broadcasting, mobile radio, or navigation devices, will be allocated in non-overlapping ranges of frequencies. For each radio band,

430-460: Is a terrestrial radio station designed for extraplanetary telecommunication with spacecraft (constituting part of the ground segment of the spacecraft system), or reception of radio waves from astronomical radio sources . Ground stations may be located either on the surface of the Earth , or in its atmosphere. Earth stations communicate with spacecraft by transmitting and receiving radio waves in

473-399: Is called a ground tracking station , or space tracking station , or simply a tracking station . When a spacecraft or satellite is within a ground station's line of sight, the station is said to have a view of the spacecraft (see pass ). A spacecraft can communicate with more than one ground station at a time. A pair of ground stations are said to have a spacecraft in mutual view when

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516-479: Is located approximately 3 km to the north-west, on Black Hill. DSS-46 was decommissioned in late 2009. In May 2010 the American Institute of Aeronautics and Astronautics declared the antenna a Historical Aerospace Site, and the antenna remains in place. CDSCC costs about A$ 20 million per year to run, and is funded by NASA. Earth station A ground station , Earth station , or Earth terminal

559-683: Is located in the Paddys River (a tributary of the Cotter River ) valley, about 20 km from Canberra in the Australian Capital Territory . The complex is part of the Deep Space Network run by NASA's Jet Propulsion Laboratory (JPL). It is commonly referred to as the Tidbinbilla Deep Space Tracking Station and was officially opened on 19 March 1965 by then Prime Minister of Australia Sir Robert Menzies . The station

602-583: Is now used for tracking and communicating with NASA's spacecraft, particularly interplanetary missions. Its DSS-43 antenna is the only antenna on Earth that can send commands to Voyager 2 . It is managed in Australia by the Commonwealth Scientific and Industrial Research Organisation (CSIRO) for NASA’s Space Communications and Navigation program (SCaN) at NASA Headquarters in Washington, D.C. The complex

645-866: Is separated from Canberra by the Murrumbidgee River and, more importantly, the Coolamon Ridge, Urambi Hills, and Bullen Range, which help shield the dishes from the city's radio frequency (RF) noise. Located nearby is the Tidbinbilla Nature Reserve . The CSIRO manages most of NASA's activities in Australia. In February 2010 CSIRO took over direct management of the site with the establishment of CASS (CSIRO Astronomy and Space Science). Previous to this CDSCC had been managed by external sub-contractor organisations, such as Raytheon Australia from 2003–2010; BAE Systems (formerly British Aerospace Australia) 1990–2003; AWA Electronic Services -1990. During

688-478: Is so great that the atmosphere is effectively opaque, until it becomes transparent again in the near-infrared and optical window frequency ranges. These ITU radio bands are defined in the ITU Radio Regulations . Article 2, provision No. 2.1 states that "the radio spectrum shall be subdivided into nine frequency bands, which shall be designated by progressive whole numbers in accordance with

731-552: Is used in coastal waters and relatively short-range communication between vessels and to shore stations. Radios are channelized, with different channels used for different purposes; marine Channel 16 is used for calling and emergencies. Amateur radio frequency allocations vary around the world. Several bands are common for amateurs worldwide, usually in the HF part of the spectrum. Other bands are national or regional allocations only due to differing allocations for other services, especially in

774-565: The ITU and the local regulating agencies like the US Federal Communications Commission (FCC) and voluntary best practices help avoid interference. As a matter of convention, the ITU divides the radio spectrum into 12 bands, each beginning at a wavelength which is a power of ten (10 ) metres, with corresponding frequency of 3×10   hertz , and each covering a decade of frequency or wavelength. Each of these bands has

817-678: The International Consultative Committee for Radio administered standards and regulations now governed by the ITU-R. 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 publishes the Intelsat Earth Station Standards (IESS) which, among other things, classifies ground stations by

860-628: The International Telecommunication Union (ITU) Radio Regulations describes various types of stationary and mobile ground stations, and their interrelationships. Specialized satellite Earth stations or satellite tracking stations are used to telecommunicate with satellites — chiefly communications satellites . Other ground stations communicate with crewed space stations or uncrewed space probes . A ground station that primarily receives telemetry data, or that follows space missions, or satellites not in geostationary orbit ,

903-483: The VHF and UHF parts of the radio spectrum. Citizens' band radio is allocated in many countries, using channelized radios in the upper HF part of the spectrum (around 27 MHz). It is used for personal, small business and hobby purposes. Other frequency allocations are used for similar services in different jurisdictions, for example UHF CB is allocated in Australia. A wide range of personal radio services exist around

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946-748: The data rate that can be transmitted. Below about 30 kHz, audio modulation is impractical and only slow baud rate data communication is used. The lowest frequencies that have been used for radio communication are around 80 Hz, in ELF submarine communications systems built by a few nations' navies to communicate with their submerged submarines hundreds of meters underwater. These employ huge ground dipole antennas 20–60 km long excited by megawatts of transmitter power, and transmit data at an extremely slow rate of about 1 bit per minute (17 millibits per second , or about 5 minutes per character). The highest frequencies useful for radio communication are limited by

989-529: The far infrared and mid infrared bands. Because it is a fixed resource, the practical limits and basic physical considerations of the radio spectrum, the frequencies which are useful for radio communication , are determined by technological limitations which are impossible to overcome. So although the radio spectrum is becoming increasingly congested, there is no possible way to add additional frequency bandwidth outside of that currently in use. The lowest frequencies used for radio communication are limited by

1032-403: The super high frequency (SHF) or extremely high frequency (EHF) bands (e.g. microwaves ). When a ground station successfully transmits radio waves to a spacecraft (or vice versa), it establishes a telecommunications link . A principal telecommunications device of the ground station is the parabolic antenna . Ground stations may have either a fixed or itinerant position. Article 1 § III of

1075-582: The ATIS Telecom Glossary, which is maintained by the Alliance for Telecommunications Industry Solutions (ATIS), an international, business-oriented, non-governmental organization . The Telecommunications Industry Association also acknowledges this definition. The ITU Radiocommunication Sector (ITU-R), a division of the International Telecommunication Union , codifies international standards agreed-upon through multinational discourse. From 1927 to 1932,

1118-456: The ITU has a band plan (or frequency plan ) which dictates how it is to be used and shared, to avoid interference and to set protocol for the compatibility of transmitters and receivers . Each frequency plan defines the frequency range to be included, how channels are to be defined, and what will be carried on those channels. Typical definitions set forth in a frequency plan are: The actual authorized frequency bands are defined by

1161-523: The VHF and UHF parts of the spectrum, are allocated for communication between fixed base stations and land mobile vehicle-mounted or portable transceivers. In the United States these services are informally known as business band radio. See also Professional mobile radio . Police radio and other public safety services such as fire departments and ambulances are generally found in the VHF and UHF parts of

1204-417: The absorption of microwave energy by the atmosphere. As frequency increases above 30 GHz (the beginning of the millimeter wave band), atmospheric gases absorb increasing amounts of power, so the power in a beam of radio waves decreases exponentially with distance from the transmitting antenna. At 30 GHz, useful communication is limited to about 1 km, but as frequency increases the range at which

1247-502: The allocation still dedicated to television, TV-band devices use channels without local broadcasters. The Apex band in the United States was a pre-WWII allocation for VHF audio broadcasting; it was made obsolete after the introduction of FM broadcasting. Airband refers to VHF frequencies 108 to 137 MHz, used for navigation and voice communication with aircraft. Trans-oceanic aircraft also carry HF radio and satellite transceivers. The greatest incentive for development of radio

1290-519: The capabilities of their parabolic antennas, and pre-approves certain antenna models. Eutelsat publishes similar standards and requirements, such as the Eutelsat Earth Station Standards (EESS). The Interagency Operations Advisory Group offers a Service Catalog describing standard services, Spacecraft Emergency Cross Support Standard, and Consultative Committee for Space Data Systems data standards. The Teleport (originally called

1333-599: The following table". The table originated with a recommendation of the fourth CCIR meeting, held in Bucharest in 1937, and was approved by the International Radio Conference held at Atlantic City, NJ in 1947. The idea to give each band a number, in which the number is the logarithm of the approximate geometric mean of the upper and lower band limits in Hz, originated with B. C. Fleming-Williams, who suggested it in

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1376-446: The increasing size of transmitting antennas required. The size of antenna required to radiate radio power efficiently increases in proportion to wavelength or inversely with frequency. Below about 10 kHz (a wavelength of 30 km), elevated wire antennas kilometers in diameter are required, so very few radio systems use frequencies below this. A second limit is the decreasing bandwidth available at low frequencies, which limits

1419-452: The largest use of these bands has been by short-range low-power communications systems, since users do not have to hold a radio operator's license. Cordless telephones , wireless computer networks , Bluetooth devices, and garage door openers all use the ISM bands. ISM devices do not have regulatory protection against interference from other users of the band. Bands of frequencies, especially in

1462-747: The mid 1960s NASA built three tracking stations in the Australian Capital Territory. As of late 2016 the station has five large antennas, called Deep Space Stations (DSS), each identified by a number: DSS-34, DSS-35, DSS-36, DSS-43, and DSS-45. The CDSCC also uses the Parkes radio telescope in central New South Wales at busy times to receive data from spacecraft (then designated DSS-49). There has been ongoing construction since 2010 building additional 34 m beam waveguide antenna . Construction of DSS-35 began in July 2010. The station's collimation tower

1505-406: The radio spectrum are a matter of convention in physics and are somewhat arbitrary. Since radio waves are the lowest frequency category of electromagnetic waves , there is no lower limit to the frequency of radio waves. Radio waves are defined by the ITU as: "electromagnetic waves of frequencies arbitrarily lower than 3000 GHz, propagated in space without artificial guide". At the high frequency end

1548-455: The radio spectrum is bounded by the infrared band. The boundary between radio waves and infrared waves is defined at different frequencies in different scientific fields. The terahertz band , from 300 gigahertz to 3 terahertz, can be considered either as microwaves or infrared. It is the highest band categorized as radio waves by the International Telecommunication Union . but spectroscopic scientists consider these frequencies part of

1591-595: The spectrum. Trunking systems are often used to make most efficient use of the limited number of frequencies available. The demand for mobile telephone service has led to large blocks of radio spectrum allocated to cellular frequencies . Reliable radio control uses bands dedicated to the purpose. Radio-controlled toys may use portions of unlicensed spectrum in the 27 MHz or 49 MHz bands, but more costly aircraft, boat, or land vehicle models use dedicated radio control frequencies near 72 MHz to avoid interference by unlicensed uses. The 21st century has seen

1634-569: The stations share simultaneous, unobstructed, line-of-sight contact with the spacecraft. A telecommunications port — or, more commonly, teleport — is a satellite ground station that functions as a hub connecting a satellite or geocentric orbital network with a terrestrial telecommunications network , such as the Internet . Teleports may provide various broadcasting services among other telecommunications functions, such as uploading computer programs or issuing commands over an uplink to

1677-464: The term has not been defined by the ITU. Broadcast frequencies: Designations for television and FM radio broadcast frequencies vary between countries, see Television channel frequencies and FM broadcast band . Since VHF and UHF frequencies are desirable for many uses in urban areas, in North America some parts of the former television broadcasting band have been reassigned to cellular phone and various land mobile communications systems. Even within

1720-468: The waves can be received decreases. In the terahertz band above 300 GHz, the radio waves are attenuated to zero within a few meters due to the absorption of electromagnetic radiation by the atmosphere (mainly due to ozone , water vapor and carbon dioxide ), which is so great that it is essentially opaque to electromagnetic emissions, until it becomes transparent again near the near-infrared and optical window frequency ranges. A radio band

1763-422: The world, usually emphasizing short-range communication between individuals or for small businesses, simplified license requirements or in some countries covered by a class license, and usually FM transceivers using around 1 watt or less. The ISM bands were initially reserved for non-communications uses of RF energy, such as microwave ovens , radio-frequency heating, and similar purposes. However, in recent years

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1806-610: Was the first application of microwaves. There are several incompatible naming systems for microwave bands, and even within a given system the exact frequency range designated by a letter may vary somewhat between different application areas. One widely used standard is the IEEE radar bands established by the US Institute of Electrical and Electronics Engineers . The band name "tremendously low frequency" (TLF) has been used for frequencies from 1–3  Hz (wavelengths of 300,000–100,000 km), but

1849-478: Was the need to communicate with ships out of visual range of shore. From the very early days of radio, large oceangoing vessels carried powerful long-wave and medium-wave transmitters. High-frequency allocations are still designated for ships, although satellite systems have taken over some of the safety applications previously served by 500 kHz and other frequencies. 2182 kHz is a medium-wave frequency still used for marine emergency communication. Marine VHF radio

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