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118-624: Movistar ( Spanish pronunciation: [moβisˈtaɾ] ) is a major telecommunications provider owned by Telefónica , operating in Spain and Hispanic American countries. It is the largest provider of landline , broadband , mobile services , and pay television ( Movistar Plus+ ) in Spain . Movistar is the second-largest wireless carrier in Mexico , with 25.8 million subscribers as of January 2020. The Movistar brand has been in use in Spain since

236-412: A thermionic tube or thermionic valve uses thermionic emission of electrons from a heated cathode for a number of fundamental electronic functions such as signal amplification and current rectification . The simplest vacuum tube, the diode invented in 1904 by John Ambrose Fleming , contains only a heated electron-emitting cathode and an anode. Electrons can only flow in one direction through

354-669: A UCI ProTeam squad in cycling under the name of Movistar Team . The 1983 song " Walking on Sunshine " by Katrina and the Waves was used by Telefónica to announce the unification of all its operation brands (Telefónica MoviStar, Bellsouth, Unifon, Telefónica Moviles, Telefónica Movil, and Movicom) in Latin America and Spain under the Movistar brand after the takeover of BellSouth's Latin America division. Movistar has also used

472-463: A line of sight path, limiting its range to the visual horizon like existing forms of visual signalling. Hertz's death in 1894 brought published reviews of his earlier discoveries including a demonstration on the transmission and detection of radio waves by the British physicist Oliver Lodge and an article about Hertz's work by Augusto Righi . Righi's article renewed Marconi's interest in developing

590-411: A radio broadcasting station , the station's large power amplifier is the transmitter and the broadcasting antenna is the interface between the power amplifier and the free space channel. The free space channel is the transmission medium and the receiver's antenna is the interface between the free space channel and the receiver. Next, the radio receiver is the destination of the radio signal, where it

708-411: A better price for their goods. In Côte d'Ivoire , coffee growers share mobile phones to follow hourly variations in coffee prices and sell at the best price. On the macroeconomic scale, Lars-Hendrik Röller and Leonard Waverman suggested a causal link between good telecommunication infrastructure and economic growth. Few dispute the existence of a correlation although some argue it is wrong to view

826-438: A caveat for it in 1876. Gray abandoned his caveat and because he did not contest Bell's priority, the examiner approved Bell's patent on March 3, 1876. Gray had filed his caveat for the variable resistance telephone, but Bell was the first to document the idea and test it in a telephone.[88] Antonio Meucci invented a device that allowed the electrical transmission of voice over a line nearly 30 years before in 1849, but his device

944-441: A connection between two or more users. For both types of networks, repeaters may be necessary to amplify or recreate the signal when it is being transmitted over long distances. This is to combat attenuation that can render the signal indistinguishable from the noise. Another advantage of digital systems over analogue is that their output is easier to store in memory, i.e., two voltage states (high and low) are easier to store than

1062-495: A continuous range of states. Telecommunication has a significant social, cultural and economic impact on modern society. In 2008, estimates placed the telecommunication industry 's revenue at US$ 4.7 trillion or just under three per cent of the gross world product (official exchange rate). Several following sections discuss the impact of telecommunication on society. On the microeconomic scale, companies have used telecommunications to help build global business empires. This

1180-498: A distance of about 6 kilometres (3.7 mi) across Salisbury Plain . On 13 May 1897, Marconi sent the first ever wireless communication over the open sea – a message was transmitted over the Bristol Channel from Flat Holm Island to Lavernock Point near Cardiff , a distance of 6 kilometres (3.7 mi). The message read "Are you ready". The transmitting equipment was almost immediately relocated to Brean Down Fort on

1298-406: A higher-frequency signal (known as the " carrier wave ") before transmission. There are several different modulation schemes available to achieve this [two of the most basic being amplitude modulation (AM) and frequency modulation (FM)]. An example of this process is a disc jockey's voice being impressed into a 96 MHz carrier wave using frequency modulation (the voice would then be received on

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1416-450: A key advantage of digital signals over analogue signals. However, digital systems fail catastrophically when noise exceeds the system's ability to autocorrect. On the other hand, analogue systems fail gracefully: as noise increases, the signal becomes progressively more degraded but still usable. Also, digital transmission of continuous data unavoidably adds quantization noise to the output. This can be reduced, but not eliminated, only at

1534-610: A member of the Fascist Grand Council . Marconi was an apologist for fascist ideology and actions such as the Italian invasion of Ethiopia in the Second Italo-Abyssinian War . In his lecture he stated: "I reclaim the honour of being the first fascist in the field of radiotelegraphy, the first who acknowledged the utility of joining the electric rays in a bundle, as Mussolini was the first in

1652-838: A new international frequency list and used in conformity with the Radio Regulation". According to the ITU's Radio Regulations adopted in Atlantic City, all frequencies referenced in the International Frequency Registration Board , examined by the board and registered on the International Frequency List "shall have the right to international protection from harmful interference". From a global perspective, there have been political debates and legislation regarding

1770-638: A patent on 2 June 1896. British Patent number 12039 titled "Improvements in Transmitting Electrical impulses and Signals, and in Apparatus therefor", which became the first patent for a communication system based on radio waves. Marconi made the first demonstration of his system for the British government in July 1896. A further series of demonstrations for the British followed, and, by March 1897, Marconi had transmitted Morse code signals over

1888-497: A patent was obtained. He also encouraged Marconi to come to Britain, where he believed it would be easier to find the necessary funds to convert his experiments into practical use. Finding little interest or appreciation for his work in Italy, Marconi travelled to London in early 1896 at the age of 21, accompanied by his mother, to seek support for his work. (He spoke fluent English in addition to Italian.) Marconi arrived at Dover , and

2006-437: A person's age, interests, sexual preference and relationship status. In this way, these sites can play important role in everything from organising social engagements to courtship . Prior to social networking sites, technologies like short message service (SMS) and the telephone also had a significant impact on social interactions. In 2000, market research group Ipsos MORI reported that 81% of 15- to 24-year-old SMS users in

2124-491: A radio as the channel "96 FM"). In addition, modulation has the advantage that it may use frequency division multiplexing (FDM). A telecommunications network is a collection of transmitters, receivers, and communications channels that send messages to one another. Some digital communications networks contain one or more routers that work together to transmit information to the correct user. An analogue communications network consists of one or more switches that establish

2242-435: A radio transmitter and receiver to his mother, a set-up that made a bell ring on the other side of the room by pushing a telegraphic button on a bench. Supported by his father, Marconi continued to read through the literature and picked up on the ideas of physicists who were experimenting with radio waves. He developed devices, such as portable transmitters and receiver systems, that could work over long distances, turning what

2360-514: A reporter from The New York Times to talk with Bride, the surviving operator. After this incident, Marconi gained popularity and became more recognised for his contributions to the field of radio and wireless technology. On 18 June 1912, Marconi gave evidence to the Court of Inquiry into the loss of Titanic regarding the marine telegraphy's functions and the procedures for emergencies at sea. Britain's Postmaster-General summed up, referring to

2478-473: A reputation for being technically conservative, in particular by continuing to use inefficient spark-transmitter technology, which could be used only for radio-telegraph operations, long after it was apparent that the future of radio communication lay with continuous-wave transmissions which were more efficient and could be used for audio transmissions. Somewhat belatedly, the company did begin significant work with continuous-wave equipment beginning in 1915, after

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2596-822: A series of tests at La Spezia , in his home country, for the Italian government. A test for Lloyd's between The Marine Hotel in Ballycastle and Rathlin Island , both in County Antrim in Ulster , Ireland , was conducted on 6 July 1898 by George Kemp and Edward Edwin Glanville . A transmission across the English Channel was accomplished on 27 March 1899, from Wimereux , France to South Foreland Lighthouse , England. Marconi set up an experimental base at

2714-475: A service that operated for a year until the gap in the telegraph link was closed. In the Middle Ages, chains of beacons were commonly 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

2832-634: A signal on behalf of the merchant vessel Elbe which had run aground on Goodwin Sands . The message was received by the radio operator of the South Foreland lighthouse, who summoned the aid of the Ramsgate lifeboat. In the autumn of 1899, his first demonstration in the United States took place. Marconi had sailed to the U.S. at the invitation of The New York Herald newspaper to cover

2950-524: A son, Giulio, 2nd Marchese Marconi (1910–1971). In 1913, the Marconi family returned to Italy and became part of Rome society. Beatrice served as a lady-in-waiting to Queen Elena . At Marconi's request, his marriage to Beatrice was annulled on 27 April 1927, so he could remarry. Marconi and Beatrice had divorced on 12 February 1924 in the free city of Fiume ( Rijeka ). Marconi went on to marry Maria Cristina Bezzi-Scali (2 April 1900 – 15 July 1994),

3068-411: A telephone network, the caller is connected to the person to whom they wish to talk by switches at various telephone exchanges . The switches form an electrical connection between the two users and the setting of these switches is determined electronically when the caller dials the number. Once the connection is made, the caller's voice is transformed to an electrical signal using a small microphone in

3186-596: A transmission from the Marconi station in Glace Bay , Nova Scotia, Canada, became the world's first radio message to cross the Atlantic from North America. In 1901, Marconi built a station near South Wellfleet, Massachusetts , that sent a message of greetings on 18 January 1903 from United States President Theodore Roosevelt to King Edward VII of the United Kingdom. However, consistent transatlantic signalling

3304-412: A version of the electrical telegraph that he unsuccessfully demonstrated on September 2, 1837. His code was an important advance over Wheatstone's signaling method. The first transatlantic telegraph cable was successfully completed on July 27, 1866, allowing transatlantic telecommunication for the first time. The conventional telephone was patented by Alexander Bell in 1876. Elisha Gray also filed

3422-581: A wireless telegraphy system based on radio waves, a line of inquiry that Marconi noted other inventors did not seem to be pursuing. At the age of 20, Marconi began to conduct experiments in radio waves, building much of his own equipment in the attic of his home at the Villa Griffone in Pontecchio (now an administrative subdivision of Sasso Marconi ), Italy, with the help of his butler, Mignani. Marconi built on Hertz's original experiments and, at

3540-581: 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 (14c., Modern French communication), from Latin communicationem (nominative communication), noun of action from past participle stem of communicare, "to share, divide out; communicate, impart, inform; join, unite, participate in," literally, "to make common", from communis". At

3658-671: Is called point-to-point communication because it occurs between a transmitter and a receiver. Telecommunication through radio broadcasts is called broadcast communication because it occurs between a powerful transmitter and numerous low-power but sensitive radio receivers. Telecommunications in which multiple transmitters and multiple receivers have been designed to cooperate and share the same physical channel are called multiplex systems . The sharing of physical channels using multiplexing often results in significant cost reduction. Multiplexed systems are laid out in telecommunication networks and multiplexed signals are switched at nodes through to

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3776-451: Is called (in the jargon of the field) " quadrature amplitude modulation " (QAM) that are used in high-capacity digital radio communication systems. Modulation can also be used to transmit the information of low-frequency analogue signals at higher frequencies. This is helpful because low-frequency analogue signals cannot be effectively transmitted over free space. Hence the information from a low-frequency analogue signal must be impressed into

3894-434: Is commonly called "keying" —a term derived from the older use of Morse Code in telecommunications—and several keying techniques exist (these include phase-shift keying , frequency-shift keying , and amplitude-shift keying ). The " Bluetooth " system, for example, uses phase-shift keying to exchange information between various devices. In addition, there are combinations of phase-shift keying and amplitude-shift keying which

4012-794: Is converted from electricity to sound. Telecommunication systems are occasionally "duplex" (two-way systems) with a single box of electronics working as both the transmitter and a receiver, or a transceiver (e.g., a mobile phone ). The transmission electronics and the receiver electronics within a transceiver are quite independent of one another. This can be explained by the fact that radio transmitters contain power amplifiers that operate with electrical powers measured in watts or kilowatts, but radio receivers deal with radio powers measured in microwatts or nanowatts . Hence, transceivers have to be carefully designed and built to isolate their high-power circuitry and their low-power circuitry from each other to avoid interference. Telecommunication over fixed lines

4130-481: Is degraded by undesirable noise . Commonly, the noise in a communication system can be expressed as adding or subtracting from the desirable signal via a random process . This form of noise is called additive noise , with the understanding that the noise can be negative or positive at different instances. Unless the additive noise disturbance exceeds a certain threshold, the information contained in digital signals will remain intact. Their resistance to noise represents

4248-609: Is self-evident in the case of online retailer Amazon.com but, according to academic Edward Lenert, even the conventional retailer Walmart has benefited from better telecommunication infrastructure compared to its competitors. In cities throughout the world, home owners use their telephones to order and arrange a variety of home services ranging from pizza deliveries to electricians. Even relatively poor communities have been noted to use telecommunication to their advantage. In Bangladesh 's Narsingdi District , isolated villagers use cellular phones to speak directly to wholesalers and arrange

4366-448: Is separated from its adjacent stations by 200 kHz, and the difference between 200 kHz and 180 kHz (20 kHz) is an engineering allowance for the imperfections in the communication system. In the example above, the "free space channel" has been divided into communications channels according to frequencies , and each channel is assigned a separate frequency bandwidth in which to broadcast radio waves. This system of dividing

4484-449: Is the informational equivalent of two newspaper pages per person per day in 1986, and six entire newspapers per person per day by 2007. Given this growth, telecommunications play an increasingly important role in the world economy and the global telecommunications industry was about a $ 4.7 trillion sector in 2012. The service revenue of the global telecommunications industry was estimated to be $ 1.5 trillion in 2010, corresponding to 2.4% of

4602-701: The Elettra , was commandeered and refitted as a warship by the German Navy. She was sunk by the RAF on 22 January 1944. After the war, the Italian Government tried to retrieve the wreckage, to rebuild the boat, and the wreckage was removed to Italy. Eventually, the idea was abandoned, and the wreckage was cut into pieces which were distributed amongst Italian museums. In 1943, the Supreme Court of

4720-535: The Marchese Marconi suffered nine heart attacks in the span of three years preceding his death. Marconi died in Rome on 20 July 1937 at age 63, following the ninth, fatal, heart attack , and Italy held a state funeral for him. As a tribute, shops on the street where he lived were "Closed for national mourning". In addition, at 6 pm the next day, the time designated for the funeral, transmitters around

4838-721: The America's Cup international yacht races off Sandy Hook , New Jersey . The transmission was done aboard the SS Ponce , a passenger ship of the Porto Rico Line . Marconi left for England on 8 November 1899 on the American Line 's SS  Saint Paul , and he and his assistants installed wireless equipment aboard during the voyage. Before this voyage the Second Boer War had begun, and Marconi's wireless

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4956-596: The BBC , and he spoke of the close association of aviation and wireless telephony in that same year at a private gathering with Florence Tyzack Parbury , and even spoke of interplanetary wireless communication. In 1924, the Marconi Company co-established the Unione Radiofonica Italiana (now RAI ). Have I done the world good, or have I added a menace? In 1914, Marconi was made a Senator in

5074-582: The Elettra ' s crew was Adelmo Landini , his personal radio operator, who was also an inventor. In December 1898, the British lightship service authorised the establishment of wireless communication between the South Foreland lighthouse at Dover and the East Goodwin lightship , twelve miles distant. On 17 March 1899, the East Goodwin lightship sent the first wireless distress signal ,

5192-602: The Haven Hotel , Sandbanks , Poole Harbour , Dorset , where he erected a 100-foot high mast. He became friends with the van Raaltes, the owners of Brownsea Island in Poole Harbour, and his steam yacht, the Elettra , was often moored on Brownsea or at The Haven Hotel. Marconi purchased the vessel after the Great War and converted it to a seaborne laboratory from where he conducted many of his experiments. Among

5310-646: The New Radicals ' hit " You Get What You Give " and " Two Princes " by Spin Doctors . Currently " Hey, Soul Sister " by Train is in advertising and other versions of the song are also used in audiovisual advertisements. Telecommunications Telecommunication , often used in its plural form or abbreviated as telecom , is the transmission of information with an immediacy comparable to face-to-face communication. As such, slow communications technologies like postal mail and pneumatic tubes are excluded from

5428-773: The Nipkow disk by Paul Nipkow and thus became known as the mechanical television . It formed the basis of experimental broadcasts done by the British Broadcasting Corporation beginning on 30 September 1929. However, for most of the 20th century, televisions depended on the cathode ray tube invented by Karl Ferdinand Braun . The first version of such a television to show promise was produced by Philo Farnsworth and demonstrated to his family on 7 September 1927. After World War II, interrupted experiments resumed and television became an important home entertainment broadcast medium. The type of device known as

5546-688: The Scottish founder of whiskey distillers Jameson & Sons ). His father, who was a widower with a son, Luigi, married Jameson on 16 April 1864 in Boulogne-sur-Mer , France. Alfonso, Marconi's older brother, was born in 1865. Between the ages of two and six, Marconi and Alfonso lived with their mother in the English town of Bedford . Having an Irish mother helped explain Marconi's many activities in Great Britain and Ireland. When he

5664-889: The Senate of the Kingdom of Italy and appointed Honorary Knight Grand Cross of the Royal Victorian Order in the UK. During World War I , Italy joined the Allied side of the conflict, and Marconi was placed in charge of the Italian military's radio service. He attained the rank of lieutenant in the Italian Royal Army and of commander in the Regia Marina . In 1929, he was made a marquess by King Victor Emmanuel III . While helping to develop microwave technology,

5782-698: The Somerset coast, stretching the range to 16 kilometres (9.9 mi). Impressed by these and other demonstrations, Preece introduced Marconi's ongoing work to the general public at two important London lectures: "Telegraphy without Wires", at the Toynbee Hall on 11 December 1896; and "Signalling through Space without Wires", given to the Royal Institution on 4 June 1897. Numerous additional demonstrations followed, and Marconi began to receive international attention. In July 1897, he carried out

5900-465: The Titanic disaster: "Those who have been saved, have been saved through one man, Mr. Marconi ... and his marvellous invention." Marconi was offered free passage on Titanic before she sank, but had taken Lusitania three days earlier. As his daughter Degna later explained, he had paperwork to do and preferred the public stenographer aboard that vessel. Over the years, the Marconi companies gained

6018-815: The White Star Line but by the Marconi International Marine Communication Company . After the sinking of the ocean liner, survivors were rescued by the RMS Carpathia of the Cunard Line . Carpathia took a total of 17 minutes to both receive and decode the SOS signal sent by Titanic . There was a distance of 58 miles between the two ships. When Carpathia docked in New York, Marconi went aboard with

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6136-440: The spark gap transmitter for radio or mechanical computers for computing, it was the invention of the thermionic vacuum tube that made these technologies widespread and practical, leading to the creation of electronics . In the 1940s, the invention of semiconductor devices made it possible to produce solid-state devices, which are smaller, cheaper, and more efficient, reliable, and durable than thermionic tubes. Starting in

6254-705: The 1932 Plenipotentiary Telegraph Conference and the International Radiotelegraph Conference in Madrid, the two organizations merged to form the International Telecommunication Union (ITU). They defined telecommunication as "any telegraphic or telephonic communication of signs, signals, writing, facsimiles and sounds of any kind, by wire, wireless or other systems or processes of electric signaling or visual signaling (semaphores)." The definition

6372-497: The 1970s. In the 1960s, Paul Baran and, independently, Donald Davies started to investigate packet switching , a technology that sends a message in portions to its destination asynchronously without passing it through a centralized mainframe . A four-node network emerged on 5 December 1969, constituting the beginnings of the ARPANET , which by 1981 had grown to 213 nodes . ARPANET eventually merged with other networks to form

6490-787: The Customs officer opened his case to find various apparatuses. The customs officer immediately contacted the Admiralty in London. With worries in the UK about Italian anarchists and suspicion Marconi was importing a bomb, his equipment was destroyed. While in the UK, Marconi gained the interest and support of William Preece , the Chief Electrical Engineer of the General Post Office (the GPO). Marconi applied for

6608-466: The ITU was able to compile an index that measures the overall ability of citizens to access and use information and communication technologies. Using this measure, Sweden, Denmark and Iceland received the highest ranking while the African countries Niger , Burkina Faso and Mali received the lowest. Telecommunication has played a significant role in social relationships. Nevertheless, devices like

6726-744: The Internet. While Internet development was a focus of the Internet Engineering Task Force (IETF) who published a series of Request for Comments documents, other networking advancements occurred in industrial laboratories , such as the local area network (LAN) developments of Ethernet (1983), Token Ring (1984) and Star network topology. The effective capacity to exchange information worldwide through two-way telecommunication networks grew from 281 petabytes (PB) of optimally compressed information in 1986 to 471 PB in 1993 to 2.2 exabytes (EB) in 2000 to 65 EB in 2007. This

6844-529: The Italian Ministry of Post and Telegraphs, then under the direction of Maggiorino Ferraris, explaining his wireless telegraph machine and asking for funding, but never received a response. An apocryphal tale claims that the minister (incorrectly named first as Emilio Sineo, later as Pietro Lacava ) wrote "to the Longara" on the document, referring to the insane asylum on Via della Lungara in Rome, but

6962-502: The Needles Station at the Isle of Wight, was published on board the SS Saint Paul before its arrival. At the turn of the 20th century, Marconi began investigating a means to signal across the Atlantic to compete with the transatlantic telegraph cables . Marconi established a wireless transmitting station at Marconi House, Rosslare Strand , County Wexford , in 1901 to act as a link between Poldhu in Cornwall , England, and Clifden in Connemara , County Galway , Ireland. He soon made

7080-442: The United Kingdom had used the service to coordinate social arrangements and 42% to flirt. In cultural terms, telecommunication has increased the public's ability to access music and film. With television, people can watch films they have not seen before in their own home without having to travel to the video store or cinema. With radio and the Internet, people can listen to music they have not heard before without having to travel to

7198-489: The United States handed down a decision on Marconi's radio patents restoring some of the prior patents of Oliver Lodge , John Stone Stone , and Nikola Tesla . The decision was not about Marconi's original radio patents and the court declared that their decision had no bearing on Marconi's claim as the first to achieve radio transmission, just that since Marconi's claim to certain patents was questionable, he could not claim infringement on those same patents. There are claims

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7316-459: The United States was spent on media that depend upon telecommunication. Many countries have enacted legislation which conforms to the International Telecommunication Regulations established by the International Telecommunication Union (ITU), which is the "leading UN agency for information and communication technology issues". In 1947, at the Atlantic City Conference, the ITU decided to "afford international protection to all frequencies registered in

7434-429: The announcement that the message was received at Signal Hill in St. John's , Newfoundland (now part of Canada ), on 12 December 1901, using a 500-foot (150 m) kite-supported antenna for reception – signals transmitted by the company's new high-power station at Poldhu , Cornwall. The distance between the two points was about 2,200 miles (3,500 km). It was heralded as a great scientific advance, yet there also

7552-417: The caller's handset . This electrical signal is then sent through the network to the user at the other end where it is transformed back into sound by a small speaker in that person's handset. Guglielmo Marconi Marconi was also an entrepreneur, businessman, and founder of The Wireless Telegraph & Signal Company in the United Kingdom in 1897 (which became the Marconi Company ). In 1929, Marconi

7670-407: The company struggled for many years to provide reliable communication to others. The role played by Marconi Co. wireless in maritime rescues raised public awareness of the value of radio and brought fame to Marconi, particularly the sinking of RMS Titanic on 15 April 1912 and RMS Lusitania on 7 May 1915. RMS Titanic radio operators Jack Phillips and Harold Bride were not employed by

7788-437: The correct destination terminal receiver. Communications can be encoded as analogue or digital signals , which may in turn be carried by analogue or digital communication systems. Analogue signals vary continuously with respect to the information, while digital signals encode information as a set of discrete values (e.g., a set of ones and zeroes). During propagation and reception, information contained in analogue signals

7906-574: The daytime is not possible because of the heavy absorption of the skywave in the ionosphere. It was not a blind test; Marconi knew in advance to listen for a repetitive signal of three clicks, signifying the Morse code letter S . The clicks were reported to have been heard faintly and sporadically. There was no independent confirmation of the reported reception, and the transmissions were difficult to distinguish from atmospheric noise. A detailed technical review of Marconi's early transatlantic work appears in John S. Belrose's work of 1995. The Poldhu transmitter

8024-500: The definition. Many transmission media have been used for telecommunications throughout history, from smoke signals , beacons , semaphore telegraphs , signal flags , and optical heliographs to wires and empty space made to carry electromagnetic signals. These paths of transmission may be divided into communication channels for multiplexing , allowing for a single medium to transmit several concurrent communication sessions . Several methods of long-distance communication before

8142-415: The development of optical fibre. The Internet , a technology independent of any given medium, has provided global access to services for individual users and further reduced location and time limitations on communications. Telecommunication is a compound noun of the Greek prefix tele- (τῆλε), meaning distant , far off , or afar , and the Latin verb communicare , meaning to share . Its modern use

8260-537: The device—from the cathode to the anode. Adding one or more control grids within the tube enables the current between the cathode and anode to be controlled by the voltage on the grid or grids. These devices became a key component of electronic circuits for the first half of the 20th century and were crucial to the development of radio, television, radar, sound recording and reproduction , long-distance telephone networks, and analogue and early digital computers . While some applications had used earlier technologies such as

8378-422: The electrical telegraph, the last commercial line was abandoned in 1880. On July 25, 1837, the first commercial electrical telegraph was demonstrated by English inventor Sir William Fothergill Cooke and English scientist Sir Charles Wheatstone . Both inventors viewed their device as "an improvement to the [existing] electromagnetic telegraph" and not as a new device. Samuel Morse independently developed

8496-403: The expense of increasing the channel bandwidth requirement. The term "channel" has two different meanings. In one meaning, a channel is the physical medium that carries a signal between the transmitter and the receiver. Examples of this include the atmosphere for sound communications, glass optical fibres for some kinds of optical communications , coaxial cables for communications by way of

8614-458: The first decade of the 20th century, a revolution in wireless communication began with breakthroughs including those made in radio communications by Guglielmo Marconi , who won the 1909 Nobel Prize in Physics . Other early pioneers in electrical and electronic telecommunications include co-inventors of the telegraph Charles Wheatstone and Samuel Morse , numerous inventors and developers of

8732-692: The first to show that radio signals for medium wave and longwave transmissions travel much farther at night than during the day. During the daytime, signals had been received up to only about 700 miles (1,100 km), less than half of the distance claimed earlier at Newfoundland, where the transmissions had also taken place during the day. Because of this, Marconi had not fully confirmed the Newfoundland claims, although he did prove that radio signals could be sent for hundreds of kilometres (miles), despite some scientists' belief that they were limited essentially to line-of-sight distances. On 17 December 1902,

8850-506: The frequency of the waves compared to the dipole antennas used by Hertz, and radiated vertically polarized radio waves which could travel longer distances. By this point, he concluded that a device could become capable of spanning greater distances, with additional funding and research, and would prove valuable both commercially and militarily. Marconi's experimental apparatus proved to be the first engineering-complete, commercially successful radio transmission system. Marconi applied to

8968-697: The high court was trying to nullify a World War I claim against the United States government by the Marconi Company via simply restoring the non-Marconi prior patent. Marconi was a friend of Charles van Raalte and his wife Florence, the owners of Brownsea Island ; and of Margherita, their daughter, and in 1904 he met her Irish friend, The Hon. Beatrice O'Brien (1882–1976), a daughter of The 14th Baron Inchiquin . On 16 March 1905, Beatrice O'Brien and Marconi were married, and spent their honeymoon on Brownsea Island. They had three daughters, Lucia (born and died 1906), Degna (1908–1998), and Gioia (1916–1996), and

9086-431: The importance of social conversations and staying connected to family and friends. Since then the role that telecommunications has played in social relations has become increasingly important. In recent years, the popularity of social networking sites has increased dramatically. These sites allow users to communicate with each other as well as post photographs, events and profiles for others to see. The profiles can list

9204-596: The introduction of the oscillating vacuum tube (valve). The New Street Works factory in Chelmsford was the location for the first entertainment radio broadcasts in the United Kingdom in 1920, employing a vacuum tube transmitter and featuring Dame Nellie Melba . In 1922, regular entertainment broadcasts commenced from the Marconi Research Centre at Great Baddow , forming the prelude to

9322-565: The launch of GSM services in 1995. The name became effective worldwide on April 5, 2005, after Telefónica purchased the BellSouth mobile operations branch in South America . After the purchase of O 2 in 2005 by Telefónica, the company announced that the «O 2 » brand would continue to be used in the United Kingdom and Germany , as a separate branch with its own board and management structure. Since 2011, Telefónica has sponsored

9440-642: The letter was never found. In 1896, Marconi spoke with his family friend Carlo Gardini, Honorary Consul at the United States Consulate in Bologna, about leaving Italy to go to Great Britain . Gardini wrote a letter of introduction to the Ambassador of Italy in London, Annibale Ferrero, explaining who Marconi was and about his extraordinary discoveries. In his response, Ambassador Ferrero advised them not to reveal Marconi's results until after

9558-552: The management of telecommunication and broadcasting. The history of broadcasting discusses some debates in relation to balancing conventional communication such as printing and telecommunication such as radio broadcasting. The onset of World War II brought on the first explosion of international broadcasting propaganda. Countries, their governments, insurgents, terrorists, and militiamen have all used telecommunication and broadcasting techniques to promote propaganda. Patriotic propaganda for political movements and colonization started

9676-449: The maximum transmission distance for radio waves. A breakthrough came in the summer of 1895, when Marconi found that a much greater range could be achieved after he raised the height of his antenna and, borrowing from a technique used in wired telegraphy, grounded his transmitter and receiver. With these improvements, the system was capable of transmitting signals up to 2 miles (3.2 km) and over hills. The monopole antenna reduced

9794-567: The medium into channels according to frequency is called " frequency-division multiplexing ". Another term for the same concept is " wavelength-division multiplexing ", which is more commonly used in optical communications when multiple transmitters share the same physical medium. Another way of dividing a communications medium into channels is to allocate each sender a recurring segment of time (a "time slot", for example, 20 milliseconds out of each second), and to allow each sender to send messages only within its own time slot. This method of dividing

9912-414: The medium into communication channels is called " time-division multiplexing " ( TDM ), and is used in optical fibre communication. Some radio communication systems use TDM within an allocated FDM channel. Hence, these systems use a hybrid of TDM and FDM. The shaping of a signal to convey information is known as modulation . Modulation can be used to represent a digital message as an analogue waveform. This

10030-629: The microphone: "With the help of God, who places so many mysterious forces of nature at man's disposal, I have been able to prepare this instrument which will give to the faithful of the entire world the joy of listening to the voice of the Holy Father". Marconi joined the National Fascist Party in 1923. In 1930, Italian dictator Benito Mussolini appointed him President of the Royal Academy of Italy , which made Marconi

10148-742: The mid-1930s. In 1936, the BBC broadcast propaganda to the Arab World to partly counter similar broadcasts from Italy, which also had colonial interests in North Africa. Modern political debates in telecommunication include the reclassification of broadband Internet service as a telecommunications service (also called net neutrality ), regulation of phone spam , and expanding affordable broadband access. According to data collected by Gartner and Ars Technica sales of main consumer's telecommunication equipment worldwide in millions of units was: In

10266-540: The mid-1960s, thermionic tubes were replaced with the transistor . Thermionic tubes still have some applications for certain high-frequency amplifiers. On 11 September 1940, George Stibitz transmitted problems for his Complex Number Calculator in New York using a teletype and received the computed results back at Dartmouth College in New Hampshire . This configuration of a centralized computer ( mainframe ) with remote dumb terminals remained popular well into

10384-429: The modern era used sounds like coded drumbeats , the blowing of horns , and whistles . Long-distance technologies invented during the 20th and 21st centuries generally use electric power, and include the telegraph , telephone , television , and radio . Early telecommunication networks used metal wires as the medium for transmitting signals. These networks were used for telegraphy and telephony for many decades. In

10502-452: The music store. Telecommunication has also transformed the way people receive their news. A 2006 survey (right table) of slightly more than 3,000 Americans by the non-profit Pew Internet and American Life Project in the United States the majority specified television or radio over newspapers. Telecommunication has had an equally significant impact on advertising. TNS Media Intelligence reported that in 2007, 58% of advertising expenditure in

10620-400: The neighbourhood of 94.5  MHz (megahertz) while another radio station can simultaneously broadcast radio waves at frequencies in the neighbourhood of 96.1 MHz. Each radio station would transmit radio waves over a frequency bandwidth of about 180  kHz (kilohertz), centred at frequencies such as the above, which are called the "carrier frequencies" . Each station in this example

10738-572: The only daughter of Francesco, Count Bezzi-Scali. To do this he had to be confirmed in the Catholic faith and became a devout member of the Church. He was baptised Catholic but had been brought up as a member of the Anglican Church . On 12 June 1927, Marconi married Maria Cristina in a civil service, with a religious ceremony performed on 15 June. Marconi was 53 years old and Maria Cristina

10856-521: The political field who acknowledged the necessity of merging all the healthy energies of the country into a bundle, for the greater greatness of Italy". Not one Jew was allowed to join the Royal Academy during Marconi's tenure as president from 1930, three years before Adolf Hitler took power in Germany and eight years before Benito Mussolini 's race laws brought his regime's antisemitism into

10974-515: The presence or absence of an atmosphere between the two. Radio waves travel through a perfect vacuum just as easily as they travel through air, fog, clouds, or any other kind of gas. The other meaning of the term "channel" in telecommunications is seen in the phrase communications channel , which is a subdivision of a transmission medium so that it can be used to send multiple streams of information simultaneously. For example, one radio station can broadcast radio waves into free space at frequencies in

11092-709: The relationship as causal. Because of the economic benefits of good telecommunication infrastructure, there is increasing worry about the inequitable access to telecommunication services amongst various countries of the world—this is known as the digital divide . A 2003 survey by the International Telecommunication Union (ITU) revealed that roughly a third of countries have fewer than one mobile subscription for every 20 people and one-third of countries have fewer than one land-line telephone subscription for every 20 people. In terms of Internet access, roughly half of all countries have fewer than one out of 20 people with Internet access. From this information, as well as educational data,

11210-559: The suggestion of Righi, began using a coherer , an early detector based on the 1890 findings of French physicist Édouard Branly and used in Lodge's experiments, that changed resistance when exposed to radio waves. In the summer of 1894, he built a storm alarm made up of a battery, a coherer, and an electric bell, which went off when it picked up the radio waves generated by lightning. Late one night, in December 1894, Marconi demonstrated

11328-516: The telephone including Antonio Meucci , Philipp Reis , Elisha Gray and Alexander Graham Bell , inventors of radio Edwin Armstrong and Lee de Forest , as well as inventors of television like Vladimir K. Zworykin , John Logie Baird and Philo Farnsworth . Since the 1960s, the proliferation of digital technologies has meant that voice communications have gradually been supplemented by data. The physical limitations of metallic media prompted

11446-412: The telephone system were originally advertised with an emphasis on the practical dimensions of the device (such as the ability to conduct business or order home services) as opposed to the social dimensions. It was not until the late 1920s and 1930s that the social dimensions of the device became a prominent theme in telephone advertisements. New promotions started appealing to consumers' emotions, stressing

11564-575: The then-newly discovered phenomenon of radio waves , demonstrating, by 1901, that they could be transmitted across the Atlantic Ocean. This was the start of wireless telegraphy by radio. On 17 December 1902, a transmission from the Marconi station in Glace Bay, Nova Scotia, Canada , became the world's first radio message to cross the Atlantic from North America. In 1904, a commercial service

11682-785: The university and also to use the university's laboratory and library. From youth, Marconi was interested in science and electricity. In the early 1890s, he began working on the idea of " wireless telegraphy " – i.e., the transmission of telegraph messages without connecting wires as used by the electric telegraph . This was not a new idea; numerous investigators and inventors had been exploring wireless telegraph technologies and even building systems using electric conduction , electromagnetic induction and optical (light) signalling for over 50 years, but none had proved technically and commercially successful. A relatively new development came from Heinrich Hertz , who, in 1888, demonstrated that one could produce and detect electromagnetic radiation , based on

11800-490: The voltages and electric currents in them, and free space for communications using visible light , infrared waves, ultraviolet light , and radio waves . Coaxial cable types are classified by RG type or "radio guide", terminology derived from World War II. The various RG designations are used to classify the specific signal transmission applications. This last channel is called the "free space channel". The sending of radio waves from one place to another has nothing to do with

11918-439: The wartime purposes of aircraft and land communication, radio navigation, and radar. Development of stereo FM broadcasting of radio began in the 1930s in the United States and the 1940s in the United Kingdom, displacing AM as the dominant commercial standard in the 1970s. On March 25, 1925, John Logie Baird demonstrated the transmission of moving pictures at the London department store Selfridges . Baird's device relied upon

12036-580: The winter when they would leave Bologna for the warmer climate of Tuscany or Florence . Marconi noted an important mentor was professor Vincenzo Rosa, a high school physics teacher in Livorno . Rosa taught the 17-year-old Marconi the basics of physical phenomena as well as new theories on electricity. At the age of 18 and back in Bologna, Marconi became acquainted with University of Bologna physicist Augusto Righi , who had done research on Heinrich Hertz 's work. Righi permitted Marconi to attend lectures at

12154-432: The work of James Clerk Maxwell . At the time, this radiation was commonly called "Hertzian" waves, and is now generally referred to as radio waves . There was a great deal of interest in radio waves in the physics community, but this interest was in the scientific phenomenon, not in its potential as a communication method. Physicists generally looked on radio waves as an invisible form of light that could only travel along

12272-478: The world observed two minutes of silence in his honour. The British Post Office also sent a message requesting that all broadcasting ships honour Marconi with two minutes of broadcasting silence. His remains are housed in the Mausoleum of Guglielmo Marconi in the grounds of Villa Griffone at Sasso Marconi , Emilia-Romagna, which assumed that name in his honour in 1938. In 1943, Marconi's elegant sailing yacht,

12390-418: The world's gross domestic product (GDP). Modern telecommunication is founded on a series of key concepts that experienced progressive development and refinement in a period of well over a century: Telecommunication technologies may primarily be divided into wired and wireless methods. Overall, a basic telecommunication system consists of three main parts that are always present in some form or another: In

12508-413: Was 26. They had one daughter, Maria Elettra Elena Anna (born 1930), who married Prince Carlo Giovannelli (1942–2016) in 1966; they later divorced. For unexplained reasons, Marconi left his entire fortune to his second wife and their only child, and nothing to the children of his first marriage. Marconi wanted to personally introduce in 1931 the first radio broadcast of a Pope, Pius XI , and announced at

12626-599: Was a two-stage circuit. Feeling challenged by sceptics, Marconi prepared a better-organised and documented test. In February 1902, the SS Philadelphia sailed west from Great Britain with Marconi aboard, carefully recording signals sent daily from the Poldhu station. The test results produced coherer-tape reception up to 1,550 miles (2,490 km), and audio reception up to 2,100 miles (3,400 km). The maximum distances were achieved at night, and these tests were

12744-491: Was difficult to establish. Marconi began to build high-powered stations on both sides of the Atlantic to communicate with ships at sea, in competition with other inventors. In 1904, he established a commercial service to transmit nightly news summaries to subscribing ships, which could incorporate them into their on-board newspapers. A regular transatlantic radio-telegraph service was finally begun on 17 October 1907 between Clifden , Ireland, and Glace Bay , but even after this

12862-490: 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 (or semaphore line ) between Lille and Paris. However semaphore suffered from the need for skilled operators and expensive towers at intervals of ten to thirty kilometres (six to nineteen miles). As a result of competition from

12980-703: Was ennobled as a Marchese (marquis) by King Victor Emmanuel III of Italy, and, in 1931, he set up Vatican Radio for Pope Pius XI . Guglielmo Giovanni Maria Marconi was born in Palazzo Marescalchi in Bologna on 25 April 1874, the second son of Giuseppe Marconi (an Italian aristocratic landowner from Porretta Terme who lived in the countryside of Pontecchio ) and his Irish wife Annie Jameson (daughter of Andrew Jameson of Daphne Castle in County Wexford , and granddaughter of John Jameson,

13098-427: Was essentially a laboratory experiment into a useful communication system. Marconi came up with a functional system with many components: In the summer of 1895, Marconi moved his experiments outdoors on his father's estate in Bologna. He tried different arrangements and shapes of antenna but even with improvements he was able to transmit signals only up to one half-mile, a distance Oliver Lodge had predicted in 1894 as

13216-407: Was established to transmit nightly news summaries to subscribing ships, which incorporated them into their onboard newspapers. 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 the development of radio for

13334-471: Was later reconfirmed, according to Article 1.3 of the ITU Radio Regulations , which defined it as "Any transmission , emission or reception of signs, signals, writings, images and sounds or intelligence of any nature by wire , radio, optical, or other electromagnetic systems". Homing pigeons have been used throughout history by different cultures. Pigeon post had Persian roots and

13452-676: Was later used by the Romans to aid their military. Frontinus claimed Julius Caesar used pigeons as messengers in his conquest of Gaul . The Greeks also 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 Java and Sumatra . And in 1849, Paul Julius Reuter started a pigeon service to fly stock prices between Aachen and Brussels ,

13570-486: Was of little practical value because it relied on the electrophonic effect requiring users to place the receiver in their mouths to "hear". The first commercial telephone services were set up by the Bell Telephone Company in 1878 and 1879 on both sides of the Atlantic in the cities of New Haven and London. In 1894, Italian inventor Guglielmo Marconi began developing a wireless communication using

13688-465: Was three years old, on 4 May 1877, Giuseppe Marconi decided to obtain British citizenship. Marconi could have thus also opted for British citizenship anytime, as both his parents had British citizenship. Marconi did not attend school as a child and did not go on to formal higher education. Instead, he learned chemistry, mathematics, and physics at home from a series of private tutors hired by his parents. His family hired additional tutors for Marconi in

13806-545: Was to bring news of the conflict to passengers at the request of "some of the officials of the American line." On 15 November the SS Saint Paul became the first ocean liner to report her imminent return to Great Britain by wireless when Marconi's Royal Needles Hotel radio station contacted her 66 nautical miles off the English coast. The first Transatlantic Times , a newspaper containing wireless transmission news from

13924-471: Was – and continues to be – considerable scepticism about this claim. The exact wavelength used is not known, but it is fairly reliably determined to have been in the neighbourhood of 350 metres (frequency ≈ 850 kHz). The tests took place at a time of day during which the entire transatlantic path was in daylight. It is now known (although Marconi did not know then) that this was the worst possible choice. At this medium wavelength, long-distance transmission in

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