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Aeronautical Mobile Radiocommunication Service
Aeronautical mobile service (short: AMS; also aeronautical mobile radiocommunication service) is a form of aviation communication conducted through radio. The ITU Radio Regulations divide AMS into communication used for civil air route flights (R) and off-route flights (OR). Aeronautical mobile (R) service is a so-called safety-of-life service, must be protected for interferences, and is an essential part of air traffic control. Communication occurs between radio stations onboard aircraft, termed aircraft stations, and terrestrial stations that are sometimes termed "aeronautical stations". Communication can also occur between aircraft. AMS is commonly used in air traffic control. Aeronautical mobile satellite service Aeronautical mobile satellite service (AMSS) is a form of AMS where an aircraft station is connected to a communications satellite. It is useful in situations where the aircraft is far away from any radio station on land. Frequency allocation The allocation of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aircraft Station
An aircraft station (also aircraft radio station) is – according to ''Article 1.83'' of the International Telecommunication Union, International Telecommunication Union's (ITU) ITU Radio Regulations (RR)ITU Radio Regulations, Section IV. Radio Stations and Systems – Article 1.83, definition: ''aircraft radio station / aircraft radio station'' – defined as "A mobile radio station in the aeronautical mobile service, other than survival craft station, located on board an aircraft". Each station shall be classified by the service in which it operates permanently or temporarily. ;See also: ;Selection of UHF/VHF aircraft stations US Navy 030806-N-8629M-002 Lt. Stacy Justeson, a pilot with the 'Providers' of Fleet Logistics Squadron Thirty (VRC 30).jpg, US Navy Grumman C-2 Greyhound used for Aeronautical mobile (OR) service Arc-164-rt.jpg, AN/ARC-164 (Receiver/Transmitter RT-1504) used for Aeronautical mobile (OR) service/HAVE QUICK, HQ II Arc-164-ctrl.jpg, AN/ARC-164 (Control ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radiocommunication Service
Radio is the technology of communicating using radio waves. Radio waves are electromagnetic waves of frequency between 3 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmitter connected to an antenna which radiates the waves. They can be received by other antennas connected to a radio receiver; this is the fundamental principle of radio communication. In addition to communication, radio is used for radar, radio navigation, remote control, remote sensing, and other applications. In radio communication, used in radio and television broadcasting, cell phones, two-way radios, wireless networking, and satellite communication, among numerous other uses, radio waves are used to carry information across space from a transmitter to a receiver, by modulating the radio signal (impressing an information signal on the radio wave by varying some aspect of the wave) in the transmitter. In radar, used to locate and track objects like air ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio Station
Radio broadcasting is the broadcasting of audio (sound), sometimes with related metadata, by radio waves to radio receivers belonging to a public audience. In terrestrial radio broadcasting the radio waves are broadcast by a land-based radio station, while in '' satellite radio'' the radio waves are broadcast by a satellite in Earth orbit. To receive the content the listener must have a broadcast radio receiver (''radio''). Stations are often affiliated with a radio network that provides content in a common radio format, either in broadcast syndication or simulcast, or both. The encoding of a radio broadcast depends on whether it uses an analog or digital signal. Analog radio broadcasts use one of two types of radio wave modulation: amplitude modulation for AM radio, or frequency modulation for FM radio. Newer, digital radio stations transmit in several different digital audio standards, such as DAB (Digital Audio Broadcasting), HD radio, or DRM ( Digital Ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shortwave
Shortwave radio is radio transmission using radio frequencies in the shortwave bands (SW). There is no official definition of the band range, but it always includes all of the high frequency band (HF), which extends from 3 to 30 MHz (approximately 100 to 10 metres in wavelength). It lies between the medium frequency band (MF) and the bottom of the VHF band. Radio waves in the shortwave band can be reflected or refracted from a layer of electrically charged atoms in the atmosphere called the ionosphere. Therefore, short waves directed at an angle into the sky can be reflected back to Earth at great distances, beyond the horizon. This is called skywave or "skip" propagation. Thus shortwave radio can be used for communication over very long distances, in contrast to radio waves of higher frequency, which travel in straight lines (line-of-sight propagation) and are generally limited by the visual horizon, about 64 km (40 miles). Shortwave broadcasts of radio pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Telecommunication Union Region
The International Telecommunication Union (ITU), in its International Radio Regulations, divides the world into three ITU regions for the purposes of managing the global radio spectrum. Each region has its own set of frequency allocations, the main reason for defining the regions. Boundaries *Region 1 comprises Europe, Africa, the Commonwealth of Independent States, Mongolia, and the Middle East west of the Persian Gulf, including Iraq. ** The western boundary is defined by Line B and the eastern boundary is defined by Line A, except that all territory of Iran is excluded, and all territory of Armenia, Azerbaijan, Georgia, Kazakhstan, Mongolia, Uzbekistan, Kyrgyzstan, Russia, Tajikistan, Turkmenistan, Turkey and Ukraine and the area to the north of Russia which lies between lines A and C is included. *Region 2 covers the Americas including Greenland, and some of the eastern Pacific Islands. ** The eastern boundary is defined by Line B and the western boundary is defined by Line C. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frequency Allocation
Frequency allocation (or spectrum allocation) is the part of spectrum management dealing with the designation and regulation of the electromagnetic spectrum into frequency bands, normally done by governments in most countries. Because radio propagation does not stop at national boundaries, governments have sought to harmonise the allocation of RF bands and their standardization. ITU definition The International Telecommunication Union defines frequency allocation as being of "a given frequency band for the purpose of its use by one or more terrestrial or space radiocommunication services or the radio astronomy service under specified conditions".ITU Radio Regulations, Section IV. Radio Stations and Systems – Article 1.16, definition: allocation (of a frequency band). ''Frequency allocation'' is also a special term, used in national frequency administration. Other terms are: Bodies Several bodies set standards for frequency allocation, including: * International Telecomm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NJFA
__NOTOC__ The NATO Joint Civil/Military Frequency Agreement (NJFA) is the universal NATO common civil/military treaty to regulate the military access to the radio frequency spectrum in the range of 14 kHz to 100 GHz in peacetime, during exercises, in times of crisis, and in military operations. This document has been the basis for the frequency utilisation in NATO-Europe since 1982. Nations and organisations, e.g. partnership for peace countries, are invited to participate as deemed to be necessary. The national representatives of the frequency sovereignty agree unanimous to changes of the NJFA, in line to decisions of World Radiocommunication Conferences, operational requirement of the armed forces, and technical developments. However, the provision of "Article 38 of the International Telecommunication Convention, Nairobi 1982" remains untouched.International Telecommunication Convention, Nairobi 1982; § 163, 1. The member countries contain full sovereignty pertainin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Communications Satellite
A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a Transponder (satellite communications), transponder; it creates a communication channel between a source transmitter and a Radio receiver, receiver at different locations on Earth. Communications satellites are used for television, telephone, radio, internet, and military applications. Many communications satellites are in geostationary orbit above the equator, so that the satellite appears stationary at the same point in the sky; therefore the satellite dish antennas of ground stations can be aimed permanently at that spot and do not have to move to track the satellite. Others form satellite constellations in low Earth orbit, where antennas on the ground have to follow the position of the satellites and switch between satellites frequently. The radio waves used for telecommunications links travel by Line-of-sight propagation, line of sight and so are obstructe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mobile-satellite Service
Mobile-satellite service (MSS, or mobile-satellite radiocommunication service) is – according to Article 1.25 of the International Telecommunication Union's Radio Regulations – "A radiocommunication service * between mobile earth stations and one or more space stations, or between space stations used by this service; or * between mobile earth stations by means of one or more space stations. This service may also include feeder links necessary for its operation." Details Most commercial voice and some data mobile satellite services are provided by systems operating in the L-band by Iridium, Inmarsat, Globalstar and Thuraya. The L-band spectrum allocated for MSS is between 1.5 and 2.5 GHz, with the upper portion often referred to as the S-band. Constellations of low earth orbiting (LEO) satellites are used by Iridium (66 satellites) and Globalstar (48 satellites). Inmarsat and Thuraya currently use 4 (i4) and 2 geostationary satellites respectively, their L-band services ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Air Traffic Control
Air traffic control (ATC) is a service provided by ground-based air traffic controllers who direct aircraft on the ground and through a given section of controlled airspace, and can provide advisory services to aircraft in non-controlled airspace. The primary purpose of ATC is to prevent collisions, organise and expedite the flow of traffic in the air, and provide information and other support for pilots. Personnel of air traffic control monitor aircraft location in their assigned airspace by radar and communicate with the pilots by radio. To prevent collisions, ATC enforces Separation (air traffic control), traffic separation rules, which ensure each aircraft maintains a minimum amount of 'empty space' around it at all times. It is also common for ATC to provide services to all General aviation, private, Military aviation, military, and commercial aircraft operating within its airspace; not just civilian aircraft. Depending on the type of flight and the class of airspace, AT ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
