A radionavigation-satellite service is "a radiodetermination-satellite service used for the purpose of radionavigation. This service may include feeder links necessary for its operation". RNSS is regarded as a safety-of-life service and an essential part of navigation which must be protected from interferences. ITU Radio Regulations classifies radiocommunication services as: Radiodetermination service Radiodetermination-satellite service Radionavigation service Radionavigation-satellite service Maritime radionavigation service Maritime radionavigation-satellite service Aeronautical radionavigation service Aeronautical radionavigation-satellite service Examples of RNSS use Automatic dependent surveillance – broadcast GALILEO, European GNSS Global Positioning System, with Differential GPS GLONASS Beidou Augmentation system GNSS augmentation The allocation of radio frequencies is provided according to Article 5 of the ITU Radio Regulations. To improve harmonisation in spectrum utilisation, most service allocations are incorporated in national Tables of Frequency Allocations and Utilisations within the responsibility of the appropriate national administration.
Allocations are: primary: indicated by writing in capital letters secondary: indicated by small letters exclusive or shared utilization: within the responsibility of administrations. Radio station Satellite navigation Radiocommunication service International Telecommunication Union
Maritime radionavigation service
Maritime radionavigation service is – according to Article 1.44 of the International Telecommunication Union´s Radio Regulations – defined as "A radionavigation service intended for the benefit and for the safe operation of ships." This service is a so-called safety-of-life service, must be protected for interferences, is essential part of navigation. This radiocommunication service is classified in accordance with ITU Radio Regulations as follows: Radiodetermination service Radionavigation service Radionavigation-satellite service Maritime radionavigation service Maritime radionavigation-satellite service Aeronautical radionavigation service Aeronautical radionavigation-satellite service In general the maritime radionavigation service distinguishes radio stations as follows: Radionavigation mobile stations Radionavigation land stations Radio station Radiocommunication service International Telecommunication Union
Telecommunication is the transmission of signs, messages, writings and sounds or information of any nature by wire, optical or other electromagnetic systems. Telecommunication occurs when the exchange of information between communication participants includes the use of technology, it is transmitted either electrically over physical media, such as cables, or via electromagnetic radiation. Such transmission paths are divided into communication channels which afford the advantages of multiplexing. Since the Latin term communicatio is considered the social process of information exchange, the term telecommunications is used in its plural form because it involves many different technologies. Early means of communicating over a distance included visual signals, such as beacons, smoke signals, semaphore telegraphs, signal flags, optical heliographs. Other examples of pre-modern long-distance communication included audio messages such as coded drumbeats, lung-blown horns, loud whistles. 20th- and 21st-century technologies for long-distance communication involve electrical and electromagnetic technologies, such as telegraph and teleprinter, radio, microwave transmission, fiber optics, communications satellites.
A revolution in wireless communication began in the first decade of the 20th century with the pioneering developments in radio communications by Guglielmo Marconi, who won the Nobel Prize in Physics in 1909, other notable pioneering inventors and developers in the field of electrical and electronic telecommunications. These included Charles Wheatstone and Samuel Morse, Alexander Graham Bell, Edwin Armstrong and Lee de Forest, as well as Vladimir K. Zworykin, John Logie Baird and Philo Farnsworth; the word telecommunication is a compound of the Greek prefix tele, meaning distant, far off, or afar, the Latin communicare, meaning to share. Its modern use is adapted from the French, because its written use was recorded in 1904 by the French engineer and novelist Édouard Estaunié. Communication was first used as an English word in the late 14th century, it comes from Old French comunicacion, from Latin communicationem, noun of action from past participle stem of communicare "to share, divide out.
Homing pigeons have been used throughout history by different cultures. Pigeon post had Persian roots, was used by the Romans to aid their military. Frontinus said; the Greeks conveyed the names of the victors at the Olympic Games to various cities using homing pigeons. In the early 19th century, the Dutch government used the system in Sumatra, and in 1849, Paul Julius Reuter started a pigeon service to fly stock prices between Aachen and Brussels, a service that operated for a year until the gap in the telegraph link was closed. In the Middle Ages, chains of beacons were used on hilltops as a means of relaying a signal. Beacon chains suffered the drawback that they could only pass a single bit of information, so the meaning of the message such as "the enemy has been sighted" had to be agreed upon in advance. One notable instance of their use was during the Spanish Armada, when a beacon chain relayed a signal from Plymouth to London. In 1792, Claude Chappe, a French engineer, built the first fixed visual telegraphy system between Lille and Paris.
However semaphore suffered from the need for skilled operators and expensive towers at intervals of ten to thirty kilometres. As a result of competition from the electrical telegraph, the last commercial line was abandoned in 1880. On 25 July 1837 the first commercial electrical telegraph was demonstrated by English inventor Sir William Fothergill Cooke, English scientist Sir Charles Wheatstone. Both inventors viewed their device as "an improvement to the electromagnetic telegraph" not as a new device. Samuel Morse independently developed a version of the electrical telegraph that he unsuccessfully demonstrated on 2 September 1837, his code was an important advance over Wheatstone's signaling method. The first transatlantic telegraph cable was completed on 27 July 1866, allowing transatlantic telecommunication for the first time; the conventional telephone was invented independently by Alexander Bell and Elisha Gray in 1876. Antonio Meucci invented the first device that allowed the electrical transmission of voice over a line in 1849.
However Meucci's device was of little practical value because it relied upon the electrophonic effect and thus required users to place the receiver in their mouth to "hear" what was being said. The first commercial telephone services were set-up in 1878 and 1879 on both sides of the Atlantic in the cities of New Haven and London. Starting in 1894, Italian inventor Guglielmo Marconi began developing a wireless communication using the newly discovered phenomenon of radio waves, showing by 1901 that they could be transmitted across the Atlantic Ocean; this was the start of wireless telegraphy by radio. Voice and music had little early success. World War I accelerated the development of radio for military communications. After the war, commercial radio AM broadcasting began in the 1920s and became an important mass medium for entertainment and news. World War II again accelerated development of radio for the wartime purposes of aircraft and land communication, radio navigation and radar. Development of stereo FM broadcasting of radio
Radio communication service
Radio communication service or radiocommunication service is according to Article 1.19 of the International Telecommunication Union´s RR, defined as “a service…involving the transmission, emission and/or reception of radio waves for specific telecommunication purposes”. Radiocommunication is sub-divided into terrestrial radiocommunication. Space radiocommunication is defined in RR Article 1 as “any radiocommunication involving the use of one or more space stations or the use of one or more reflecting satellites or other objects in space”. Terrestrial radiocommunication is defined as “any radiocommunication other than space radiocommunication or radio astronomy”. Section III of Article 1 of the ITU Radio Regulations sets out the definitions of some 40 radio services including such services as the fixed service, the mobile service, the land mobile service, the broadcasting service, the standard frequency and time signal service as well as the definition of radio astronomy, defined as “a service involving the use of radio astronomy”.
Note that the radio astronomy service is not a radiocommunication service but a service involving the use of radio astronomy. Some services are a sub-set of another service. For example, the land mobile service can be thought of as a branch of the mobile service which encompasses the land and aeronautical mobile services. For many terrestrial radiocommunication communication services, there is a parallel space radiocommunication service e.g. the broadcasting service and the broadcasting-satellite service. Further sub-sets of some of these internationally defined services are created at the national level. For example, within the land mobile service, a country may choose to define such services as paging, dispatch two-way radio service, cellular mobile telephone service, trunked mobile radio service, etc. Many of these definitions are based upon the nature of the service being provided rather than the international concept of a radiocommunication service. In other words, the term “service” can be used in these two different ways.
No matter what definitions are adopted in a given country, with some specific exceptions which are allowed for in the ITU RRs, the use of the spectrum must fit in with the international definitions of radio services
Mobile-satellite 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. This service may include feeder links necessary for its operation." Most commercial voice and some data mobile satellite services are provided by systems operating in the L-band by Iridium, Inmarsat and Thuraya. The L-band spectrum allocated for MSS is between 1.5 and 2.5 GHz, with the upper portion referred to as the S-band. Constellations of low earth orbiting satellites are used by Globalstar. Inmarsat and Thuraya use 4 and 2 geostationary satellites their L-band services are similar but not interoperable and most terminals can only use one or the other service, although some data terminals provide a mechanical switch required due to the different polarization schemes used by both systems. Another MSS service is MSV / MSAT / LightSquared / Ligado with 2 geostationary satellites serving North America.
China has shown an upcoming S-band satellite phone which will use its launched Tiantong-1 geostationary satellite. As of mid 2016 Iridium has experienced in-orbit failures which cannot be corrected with in-orbit spare satellites, thus only 64 of the 66 satellites required for seamless global coverage are in operation; as a result, service interruptions can be observed around the equatorial region where the satellite footprints are most spread out and there is least overlap. Additionally to the four active Inmarsat 4 satellites, Inmarsat maintains some legacy L-band services on its previous generation satellites, although they are being phased out and users are invited to upgrade to i4-based services based on variations of BGAN. Inmarsat owns and operates a new fleet of three Ka-band satellites, known as the Inmarsat 5 constellation, providing high speed mobile satellite data services known as Global Express. Other MSS systems inoperative were Ico / Pendrell, TerreStar and Ellipso. Several governments operate and use MSS systems, although most make extensive use of the Iridium and Inmarsat systems.
Mexico is developing an S-band system based on its own geostationary satellites and the United States uses MUOS and other systems. The US Government runs its own gateway in Hawaii for direct access to the Iridium constellation under a contract lasting at least until 2018. Machine-to-machine:Orbcomm provides data-only M2M services using a constellation of LEO satellites in the VHF band and a partnership with Inmarsat for M2M services in the L-band. Iridium has low bandwidth modes used for M2M and Inmarsat offers an M2M version of BGAN called BGAN M2M. Interoperability: Telephone calls to satellite terminals are accomplished by dialing numbers assigned to the Global Mobile Satellite System, although most Globalstar users and some Iridium users are assigned country-based numbers. Thus, calls can be made to satellite phones from normal cellular terminals. However, pricing for terrestrial-satellite is higher than pricing for satellite-terrestrial and satellite-satellite calls. Satellite-based Internet access is fully interoperable with traditional land-based and mobile Internet and can access the same services, although cost is much higher and satellite link latency can affect some interactive services.
Due to security concerns, the satellite segment and end-user can be behind a NAT. Commercial access: In most territories, access to mobile satellite service is managed by traditional telecom companies and specialized resellers which market hardware and network access to end users, although some constellation operators market service directly to end users; this is a list of some companies providing commercial access: AST, Bluecosmo, Galaxy1, Global Marine Networks, Globalsat Group, Globe Wireless, IEC Telecom, iridium with nearly 1 million subscribers in December 2017, 368k with voice & Data services, ITC Global, inmarsat purportedly the leading provider of global mobile satellite communications services, Marlink, RigNet, Satphone Store, Telespazio, Trustcomm. In accordance with ITU Radio Regulations variations of this radiocommunication service are classified as follows:Mobile service Mobile-satellite service Land mobile-satellite service Maritime mobile-satellite service Aeronautical mobile-satellite service The allocation of radio frequencies is provided according to Article 5 of the ITU Radio Regulations.
In order to improve harmonisation in spectrum utilisation, the majority of service-allocations stipulated in this document were incorporated in national Tables of Frequency Allocations and Utilisations, with-in the responsibility of the appropriate national administration. The allocation might be primary, secondary and shared. Primary allocation: is indicated by writing in capital letters secondary allocation: is indicated by small letters exclusive or shared utilization: is within the responsibility of administrationsExample of frequency allocation Satellite phone Radio station International Telecommunication Union
As defined by FS-1037C, radiodetermination is «the determination of the position, velocity or other characteristics of an object, or the obtaining of information relating to these parameters, by means of the propagation properties of radio waves.» There are two main fields to radiodetermination: radiolocation, passive radionavigation, active. Radiodetermination service is – according to Article 1.40 of the International Telecommunication Union's Radio Regulations – defined as «A radiocommunication service for the purpose of radiodetermination.» This radiocommunication service is classified in accordance with ITU Radio Regulations as follows: Radiodetermination service Radiodetermination-satellite service' Radionavigation service Radionavigation-satellite service Maritime radionavigation service Maritime radionavigation-satellite service Aeronautical radionavigation service Aeronautical radionavigation-satellite service Radiolocation service Radiolocation-satellite service This article incorporates public domain material from the General Services Administration document "Federal Standard 1037C".
International Telecommunication Union Real time locating
Radiodetermination-satellite service is – according to Article 1.41 of the International Telecommunication Union´s Radio Regulations – defined as «A radiocommunication service for the purpose of radiodetermination involving the use of one or more space stations. This service may include feeder links necessary for its own operation.» See This radiocommunication service is classified in accordance with ITU Radio Regulations as follows: Radiodetermination service Radiodetermination-satellite service Radionavigation service Radiolocation service The below depicted satellites are carrier of space radio stations dedicated to the radiodetermination-satellite service The allocation of radio frequencies is provided according to Article 5 of the ITU Radio Regulations. In order to improve harmonisation in spectrum utilisation, the majority of service-allocations stipulated in this document were incorporated in national Tables of Frequency Allocations and Utilisations, within the responsibility of the appropriate national administration.
The allocation might be primary, secondary and shared. Primary allocation: is indicated by writing in capital letters secondary allocation: is indicated by small letters exclusive or shared utilization: is within the responsibility of administrationsExample of frequency allocation International Telecommunication Union