The history of telecommunication began with the use of smoke signals and drums in Africa, the Americas and parts of Asia. In the 1790s, the first fixed semaphore systems emerged in Europe. However, it was not until the 1830s that electrical telecommunication systems started to appear. This article details the history of telecommunication and the individuals who helped make telecommunication systems what they are today. The history of telecommunication is an important part of the larger history of communication.
The smoke signal is one of the oldest forms of long-distance communication. It is a form of visual communication used over long distance. In general smoke signals are used to transmit news, signal danger, or gather people to a common area.
Africa is the world's second largest and second most-populous continent. At about 30.3 million km2 including adjacent islands, it covers 6% of Earth's total surface area and 20% of its land area. With 1.2 billion people as of 2016, it accounts for about 16% of the world's human population. The continent is surrounded by the Mediterranean Sea to the north, the Isthmus of Suez and the Red Sea to the northeast, the Indian Ocean to the southeast and the Atlantic Ocean to the west. The continent includes Madagascar and various archipelagos. It contains 54 fully recognised sovereign states (countries), nine territories and two de facto independent states with limited or no recognition. The majority of the continent and its countries are in the Northern Hemisphere, with a substantial portion and number of countries in the Southern Hemisphere.
The Americas comprise the totality of the continents of North and South America. Together, they make up most of the land in Earth's western hemisphere and comprise the New World.
Early telecommunications included smoke signals and drums. Talking drums were used by natives in Africa, and smoke signals in North America and China. Contrary to what one might think, these systems were often used to do more than merely announce the presence of a military camp.
The talking drum is an hourglass-shaped drum from West Africa, whose pitch can be regulated to mimic the tone and prosody of human speech. It has two drumheads connected by leather tension cords, which allow the player to modulate the pitch of the drum by squeezing the cords between their arm and body.
North America is a continent entirely within the Northern Hemisphere and almost all within the Western Hemisphere. It is also considered by some to be a northern subcontinent of the Americas. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the west and south by the Pacific Ocean, and to the southeast by South America and the Caribbean Sea.
China, officially the People's Republic of China (PRC), is a country in East Asia and the world's most populous country, with a population of around 1.404 billion in 2017. Covering approximately 9,600,000 square kilometers (3,700,000 sq mi), it is the third or fourth largest country by total area. Governed by the Communist Party of China, the state exercises jurisdiction over 22 provinces, five autonomous regions, four direct-controlled municipalities, and the special administrative regions of Hong Kong and Macau.
In Rabbinical Judaism a signal was given by means of kerchiefs or flags at intervals along the way back to the high priest to indicate the goat "for Azazel" had been pushed from the cliff.
Homing pigeons have occasionally been used throughout history by different cultures. Pigeon post had Persian roots, and was later used by the Romans to aid their military.
The messenger pigeon is a variety of domestic pigeon derived from the rock pigeon, selectively bred for its ability to find its way home over extremely long distances. The wild rock pigeon has an innate homing ability, meaning that it will generally return to its nest, using magnetoreception. This made it relatively easy to breed from the birds that repeatedly found their way home over long distances. Flights as long as 1,800 km have been recorded by birds in competitive pigeon racing. Their average flying speed over moderate 965 km distances is around 97 km/h and speeds of up to 160 km/h have been observed in top racers for short distances.
Pigeon post is the use of homing pigeons to carry messages. Pigeons were effective as messengers due to their natural homing abilities. The pigeons were transported to a destination in cages, where they would be attached with messages, then the pigeon would naturally fly back to its home where the recipient could read the message. They have been used in many places around the world. Pigeons have also been used to great effect in military situations, and are in this case referred to as war pigeon.
Greek hydraulic semaphore systems were used as early as the 4th century BC. The hydraulic semaphores, which worked with water filled vessels and visual signals, functioned as optical telegraphs. However, they could only utilize a very limited range of pre-determined messages, and as with all such optical telegraphs could only be deployed during good visibility conditions.
Greece, officially the Hellenic Republic, also known as Hellas, is a country located in Southeast Europe. Its population is approximately 10.7 million as of 2018; Athens is the nation's capital and largest city, followed by Thessaloniki.
During 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 was during the Spanish Armada, when a beacon chain relayed a signal from Plymouth to London that signaled the arrival of the Spanish warships.
A beacon is an intentionally conspicuous device designed to attract attention to a specific location. A common example is the lighthouse, which provides a fixed location that can be used to navigate around obstacles or into port. More modern examples include a variety of radio beacons that can be read on radio direction finders in all weather, and radar transponders that appear on radar displays.
The Spanish Armada was a Habsburg Spanish fleet of 130 ships that sailed from Corunna in late May 1588, under the command of the Duke of Medina Sidonia, with the purpose of escorting an army from Flanders to invade England. Medina Sidonia was an aristocrat without naval command experience but was made commander by King Philip II. The aim was to overthrow Queen Elizabeth I and her establishment of Protestantism in England, to stop English interference in the Spanish Netherlands and to stop the harm caused by English and Dutch privateering ships that interfered with Spanish interests in the Americas.
Plymouth is a port city situated on the south coast of Devon, England, approximately 37 miles (60 km) south-west of Exeter and 190 miles (310 km) west-south-west of London. Enclosing the city are the mouths of the river Plym and river Tamar, which are naturally incorporated into Plymouth Sound to form a boundary with Cornwall.
French engineer Claude Chappe began working on visual telegraphy in 1790, using pairs of "clocks" whose hands pointed at different symbols. These did not prove quite viable at long distances, and Chappe revised his model to use two sets of jointed wooden beams. Operators moved the beams using cranks and wires.He built his first telegraph line between Lille and Paris, followed by a line from Strasbourg to Paris. In 1794, a Swedish engineer, Abraham Edelcrantz built a quite different system from Stockholm to Drottningholm. As opposed to Chappe's system which involved pulleys rotating beams of wood, Edelcrantz's system relied only upon shutters and was therefore faster.
However, semaphore as a communication system suffered from the need for skilled operators and expensive towers often at intervals of only ten to thirty kilometres (six to nineteen miles). As a result, the last commercial line was abandoned in 1880.
Experiments on communication with electricity, initially unsuccessful, started in about 1726. Scientists including Laplace, Ampère, and Gauss were involved.
An early experiment in electrical telegraphy was an 'electrochemical' telegraph created by the German physician, anatomist and inventor Samuel Thomas von Sömmerring in 1809, based on an earlier, less robust design of 1804 by Spanish polymath and scientist Francisco Salva Campillo.Both their designs employed multiple wires (up to 35) in order to visually represent almost all Latin letters and numerals. Thus, messages could be conveyed electrically up to a few kilometers (in von Sömmerring's design), with each of the telegraph receiver's wires immersed in a separate glass tube of acid. An electric current was sequentially applied by the sender through the various wires representing each digit of a message; at the recipient's end the currents electrolysed the acid in the tubes in sequence, releasing streams of hydrogen bubbles next to each associated letter or numeral. The telegraph receiver's operator would visually observe the bubbles and could then record the transmitted message, albeit at a very low baud rate. The principal disadvantage to the system was its prohibitive cost, due to having to manufacture and string-up the multiple wire circuits it employed, as opposed to the single wire (with ground return) used by later telegraphs.
The first working telegraph was built by Francis Ronalds in 1816 and used static electricity.
Charles Wheatstone and William Fothergill Cooke patented a five-needle, six-wire system, which entered commercial use in 1838.It used the deflection of needles to represent messages and started operating over twenty-one kilometres (thirteen miles) of the Great Western Railway on 9 April 1839. Both Wheatstone and Cooke viewed their device as "an improvement to the [existing] electromagnetic telegraph" not as a new device.
On the other side of the Atlantic Ocean, Samuel Morse developed a version of the electrical telegraph which he demonstrated on 2 September 1837. Alfred Vail saw this demonstration and joined Morse to develop the register—a telegraph terminal that integrated a logging device for recording messages to paper tape. This was demonstrated successfully over three miles (five kilometres) on 6 January 1838 and eventually over forty miles (sixty-four kilometres) between Washington, D.C. and Baltimore on 24 May 1844. The patented invention proved lucrative and by 1851 telegraph lines in the United States spanned over 20,000 miles (32,000 kilometres).Morse's most important technical contribution to this telegraph was the simple and highly efficient Morse Code, co-developed with Vail, which was an important advance over Wheatstone's more complicated and expensive system, and required just two wires. The communications efficiency of the Morse Code preceded that of the Huffman code in digital communications by over 100 years, but Morse and Vail developed the code purely empirically, with shorter codes for more frequent letters.
The submarine cable across the English Channel, wire coated in gutta percha, was laid in 1851.Transatlantic cables installed in 1857 and 1858 only operated for a few days or weeks (carried messages of greeting back and forth between James Buchanan and Queen Victoria) before they failed. The project to lay a replacement line was delayed for five years by the American Civil War. The first successful transatlantic telegraph cable was completed on 27 July 1866, allowing transatlantic telecommunication for the first time.
The electric telephone was invented in the 1870s, based on earlier work with harmonic (multi-signal) telegraphs. The first commercial telephone services were set up in 1878 and 1879 on both sides of the Atlantic in the cities of New Haven, Connecticut in the US and London, England in the UK. Alexander Graham Bell held the master patent for the telephone that was needed for such services in both countries.All other patents for electric telephone devices and features flowed from this master patent. Credit for the invention of the electric telephone has been frequently disputed, and new controversies over the issue have arisen from time-to-time. As with other great inventions such as radio, television, the light bulb, and the digital computer, there were several inventors who did pioneering experimental work on voice transmission over a wire, who then improved on each other's ideas. However, the key innovators were Alexander Graham Bell and Gardiner Greene Hubbard, who created the first telephone company, the Bell Telephone Company in the United States, which later evolved into American Telephone & Telegraph (AT&T), at times the world's largest phone company.
Telephone technology grew quickly after the first commercial services emerged, with inter-city lines being built and telephone exchanges in every major city of the United States by the mid-1880s.The first transcontinental telephone call occurred on January 25, 1915. Despite this, transatlantic voice communication remained impossible for customers until January 7, 1927 when a connection was established using radio. However no cable connection existed until TAT-1 was inaugurated on September 25, 1956 providing 36 telephone circuits.
In 1880, Bell and co-inventor Charles Sumner Tainter conducted the world's first wireless telephone call via modulated lightbeams projected by photophones. The scientific principles of their invention would not be utilized for several decades, when they were first deployed in military and fiber-optic communications.
The first transatlantic telephone cable (which incorporated hundreds of electronic amplifiers) was not operational until 1956, only six years before the first commercial telecommunications satellite, Telstar, was launched into space.
Over several years starting in 1894, the Italian inventor Guglielmo Marconi worked on adapting the newly discovered phenomenon of radio waves to telecommunication, building the first wireless telegraphy system using them.In December 1901, he established wireless communication between St. John's, Newfoundland and Poldhu, Cornwall (England), earning him a Nobel Prize in Physics (which he shared with Karl Braun) in 1909. In 1900, Reginald Fessenden was able to wirelessly transmit a human voice.
Millimetre wave communication was first investigated by Bengali physicist Jagadish Chandra Bose during 1894–1896, when he reached an extremely high frequency of up to 60 GHz in his experiments. He also introduced the use of semiconductor junctions to detect radio waves, when he patented the radio crystal detector in 1901.
In 1924, Japanese engineer Kenjiro Takayanagi began a research program on electronic television. In 1925, he demonstrated a CRT television with thermal electron emission.In 1926, he demonstrated a CRT television with 40-line resolution, the first working example of a fully electronic television receiver. In 1927, he increased the television resolution to 100 lines, which was unrivaled until 1931. In 1928, he was the first to transmit human faces in half-tones on television, influencing the later work of Vladimir K. Zworykin.
On March 25, 1925, Scottish inventor John Logie Baird publicly demonstrated the transmission of moving silhouette pictures at the London department store Selfridge's. Baird's system relied upon the fast-rotating Nipkow disk, and thus it became known as the mechanical television. In October 1925, Baird was successful in obtaining moving pictures with halftone shades, which were by most accounts the first true television pictures.This led to a public demonstration of the improved device on 26 January 1926 again at Selfridges. His invention formed the basis of semi-experimental broadcasts done by the British Broadcasting Corporation beginning September 30, 1929.
For most of the twentieth century televisions used the cathode ray tube (CRT) invented by Karl Braun. Such a television was produced by Philo Farnsworth, who demonstrated crude silhouette images to his family in Idaho on September 7, 1927.Farnsworth's device would compete with the concurrent work of Kalman Tihanyi and Vladimir Zworykin. Though the execution of the device was not yet what everyone hoped it could be, it earned Farnsworth a small production company. In 1934, he gave the first public demonstration of the television at Philadelphia's Franklin Institute and opened his own broadcasting station. Zworykin's camera, based on Tihanyi's Radioskop, which later would be known as the Iconoscope, had the backing of the influential Radio Corporation of America (RCA). In the United States, court action between Farnsworth and RCA would resolve in Farnsworth's favour. John Logie Baird switched from mechanical television and became a pioneer of colour television using cathode-ray tubes.
After mid-century the spread of coaxial cable and microwave radio relay allowed television networks to spread across even large countries.
The modern period of telecommunication history from 1950 onwards is referred to as the semiconductor era, due to the wide adoption of semiconductor devices in telecommunication technology. The development of the transistor technology and the semiconductor industry enabled significant advances in telecommunication technology, led to the price of telecommunications services declining significantly, and led to a transition away from state-owned narrowband circuit-switched networks to private broadband packet-switched networks. In turn, this led to a significant increase in the total number of telephone subscribers, reaching nearly 1 billion users worldwide by the end of the 20th century.
The development of transistor technology has been fundamental to modern electronic telecommunication.Julius Edgar Lilienfeld proposed the concept of a field-effect transistor in 1926, but it was not possible to actually construct a working device at that time. The first working transistor, a point-contact transistor, was invented by John Bardeen and Walter Houser Brattain under William Shockley's direction at Bell Labs in 1947.
The MOSFET (metal-oxide-silicon field-effect transistor), also known as the MOS transistor, was later invented by Mohamed Atalla and Dawon Kahng at Bell Labs in 1959.The MOSFET is the building block or "workhorse" of the information revolution and the information age, and the most widely manufactured device in history. MOS technology, including MOS integrated circuits and power MOSFETs, drives the communications infrastructure of modern telecommunication. Along with computers, other essential elements of modern telecommunication that are built from MOSFETs include mobile devices, transceivers, base station modules, routers, RF power amplifiers, microprocessors, memory chips, and telecommunication circuits.
According Edholm's law, the bandwidth of telecommunication networks has been doubling every 18 months.Advances in MOS technology, including MOSFET scaling (increasing transistor counts at an exponential pace, as predicted by Moore's law), has been the most important contributing factor in the rapid rise of bandwidth in telecommunications networks.
The development of videotelephony involved the historical development of several technologies which enabled the use of live video in addition to voice telecommunications. The concept of videotelephony was first popularized in the late 1870s in both the United States and Europe, although the basic sciences to permit its very earliest trials would take nearly a half century to be discovered. This was first embodied in the device which came to be known as the video telephone, or videophone, and it evolved from intensive research and experimentation in several telecommunication fields, notably electrical telegraphy, telephony, radio, and television.
The development of the crucial video technology first started in the latter half of the 1920s in the United Kingdom and the United States, spurred notably by John Logie Baird and AT&T's Bell Labs. This occurred in part, at least by AT&T, to serve as an adjunct supplementing the use of the telephone. A number of organizations believed that videotelephony would be superior to plain voice communications. However video technology was to be deployed in analog television broadcasting long before it could become practical—or popular—for videophones.
Videotelephony developed in parallel with conventional voice telephone systems from the mid-to-late 20th century. Only in the late 20th century with the advent of powerful video codecs and high-speed broadband did it become a practical technology for regular use. With the rapid improvements and popularity of the Internet, it became widespread through the use of videoconferencing and webcams, which frequently utilize Internet telephony, and in business, where telepresence technology has helped reduce the need to travel.
Practical digital videotelephony was only made possible with advances in video compression, due to the impractically high bandwidth requirements of uncompressed video. To achieve Video Graphics Array (VGA) quality video (480p resolution and 256 colors) with raw uncompressed video, it would require a bandwidth of over 92 Mbps. The most important compression technique that enabled practical digital videotelephony and videoconferencing is the discrete cosine transform (DCT). The DCT, a form of lossy compression, was first proposed by Nasir Ahmed in 1972. The DCT algorithm became the basis for the first practical video coding standard that was useful for videoconferencing, H.261, standardised by the ITU-T in 1988.
The first U.S. satellite to relay communications was Project SCORE in 1958, which used a tape recorder to store and forward voice messages. It was used to send a Christmas greeting to the world from U.S. President Dwight D. Eisenhower. In 1960 NASA launched an Echo satellite; the 100-foot (30 m) aluminized PET film balloon served as a passive reflector for radio communications. Courier 1B, built by Philco, also launched in 1960, was the world's first active repeater satellite. Satellites these days are used for many applications such as GPS, television, internet and telephone.
Telstar was the first active, direct relay commercial communications satellite. Belonging to AT&T as part of a multi-national agreement between AT&T, Bell Telephone Laboratories, NASA, the British General Post Office, and the French National PTT (Post Office) to develop satellite communications, it was launched by NASA from Cape Canaveral on July 10, 1962, the first privately sponsored space launch. Relay 1 was launched on December 13, 1962, and became the first satellite to broadcast across the Pacific on November 22, 1963.
The first and historically most important application for communication satellites was in intercontinental long distance telephony. The fixed Public Switched Telephone Network relays telephone calls from land line telephones to an earth station, where they are then transmitted a receiving satellite dish via a geostationary satellite in Earth orbit. Improvements in submarine communications cables, through the use of fiber-optics, caused some decline in the use of satellites for fixed telephony in the late 20th century, but they still exclusively service remote islands such as Ascension Island, Saint Helena, Diego Garcia, and Easter Island, where no submarine cables are in service. There are also some continents and some regions of countries where landline telecommunications are rare to nonexistent, for example Antarctica, plus large regions of Australia, South America, Africa, Northern Canada, China, Russia and Greenland.
After commercial long distance telephone service was established via communication satellites, a host of other commercial telecommunications were also adapted to similar satellites starting in 1979, including mobile satellite phones, satellite radio, satellite television and satellite Internet access. The earliest adaption for most such services occurred in the 1990s as the pricing for commercial satellite transponder channels continued to drop significantly.
Realization and demonstration, on October 29, 2001, of the first digital cinema transmission by satellite in Europeof a feature film by Bernard Pauchon , Alain Lorentz, Raymond Melwig and Philippe Binant.
On September 11, 1940, George Stibitz was able to transmit problems using teletype to his Complex Number Calculator in New York City and receive the computed results back at Dartmouth College in New Hampshire.This configuration of a centralized computer or mainframe with remote dumb terminals remained popular throughout the 1950s. However it was not until the 1960s that researchers started to investigate packet switching a technology that would allow chunks of data to be sent to different computers without first passing through a centralized mainframe. A four-node network emerged on December 5, 1969 between the University of California, Los Angeles, the Stanford Research Institute, the University of Utah and the University of California, Santa Barbara. This network would become ARPANET, which by 1981 would consist of 213 nodes. In June 1973, the first non-US node was added to the network belonging to Norway's NORSAR project. This was shortly followed by a node in London.
ARPANET's development centred on the Request for Comment process and on April 7, 1969, RFC 1 was published. This process is important because ARPANET would eventually merge with other networks to form the Internet and many of the protocols the Internet relies upon today were specified through this process. The first Transmission Control Protocol (TCP) specification, RFC 675 (Specification of Internet Transmission Control Program), was written by Vinton Cerf, Yogen Dalal, and Carl Sunshine, and published in December 1974. It coined the term "Internet" as a shorthand for internetworking. In September 1981, RFC 791 introduced the Internet Protocol v4 (IPv4). This established the TCP/IP protocol, which much of the Internet relies upon today. A more relaxed transport protocol that, unlike TCP, did not guarantee the orderly delivery of packets called the User Datagram Protocol (UDP) was submitted on 28 August 1980 as RFC 768. An e-mail protocol, SMTP, was introduced in August 1982 by RFC 821 and http://1.0 a protocol that would make the hyperlinked Internet possible was introduced on May 1996 by RFC 1945.
However, not all important developments were made through the Request for Comment process. Two popular link protocols for local area networks (LANs) also appeared in the 1970s. A patent for the Token Ring protocol was filed by Olof Söderblom on October 29, 1974.And a paper on the Ethernet protocol was published by Robert Metcalfe and David Boggs in the July 1976 issue of Communications of the ACM . The Ethernet protocol had been inspired by the ALOHAnet protocol which had been developed by electrical engineering researchers at the University of Hawaii.
Internet access became widespread late in the century, using the old telephone and television networks.
Practical digital media distribution and streaming was made possible by advances in data compression, due to the impractically high memory, storage and bandwidth requirements of uncompressed media.The most important compression technique is the discrete cosine transform (DCT), a lossy compression algorithm that was first proposed as an image compression technique by Nasir Ahmed at the University of Texas in 1972. The DCT algorithm was the basis for the first practical video coding format, H.261, in 1988. It was followed by more DCT-based video coding standards, most notably the MPEG video formats from 1991 onwards. The JPEG image format, also based on the DCT algorithm, was introduced in 1992. The development of the modified discrete cosine transform (MDCT) algorithm led to the MP3 audio coding format in 1994, and the Advanced Audio Coding (AAC) format in 1999.
Realization and demonstration, on 29 October 2001, of the first digital cinema transmission by satellite in Europeof a feature film by Bernard Pauchon, Alain Lorentz, Raymond Melwig and Philippe Binant.
The wireless revolution began in the 1990s,with the advent of digital wireless networks leading to a social revolution, and a paradigm shift from wired to wireless technology, including the proliferation of commercial wireless technologies such as cell phones, mobile telephony, pagers, wireless computer networks, cellular networks, the wireless Internet, and laptop and handheld computers with wireless connections. The wireless revolution has been driven by advances in radio frequency (RF) and microwave engineering, and the transition from analog to digital RF technology.
Advances in metal-oxide-semiconductor field-effect transistor (MOSFET, or MOS transistor) technology, the key component of the RF technology that enables digital wireless networks, has been central to this revolution.The invention of the MOSFET by Mohamed Atalla and Dawon Kahng at Bell Labs in 1959 led to the development of power MOSFET technology. Hitachi developed the vertical power MOSFET in 1969, and then the lateral-diffused metal-oxide semiconductor (LDMOS) in 1977. RF CMOS (radio frequency CMOS) integrated circuit technology was later developed by Asad Abidi at UCLA in the late 1980s. By the 1990s, RF CMOS integrated circuits were widely adopted as RF circuits, while discrete MOSFET (power MOSFET and LDMOS) devices were widely adopted as RF power amplifiers, which led to the development and proliferation of digital wireless networks. Most of the essential elements of modern wireless networks are built from MOSFETs, including base station modules, routers, telecommunication circuits, and radio transceivers. MOSFET scaling has led to rapidly increasing wireless bandwidth, which has been doubling every 18 months (as noted by Edholm's law).
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Electrical engineering is a technical discipline concerned with the study, design and application of equipment, devices and systems which use electricity, electronics, and electromagnetism. It emerged as an identified activity in the latter half of the 19th century after commercialization of the electric telegraph, the telephone, and electrical power generation, distribution and use.
Electronics comprises the physics, engineering, technology and applications that deal with the emission, flow and control of electrons in vacuum and matter.
A wireless network is a computer network that uses wireless data connections between network nodes.
The metal–oxide–semiconductor field-effect transistor (MOSFET, MOS-FET, or MOS FET), also known as the metal–oxide–silicon transistor (MOS transistor, or MOS), is a type of field-effect transistor that is fabricated by the controlled oxidation of a semiconductor, typically silicon. It has a covered gate, whose voltage determines the conductivity of the device. This ability to change conductivity with the amount of applied voltage can be used for amplifying or switching electronic signals. The MOSFET was invented by Egyptian engineer Mohamed M. Atalla and Korean engineer Dawon Kahng at Bell Labs in November 1959. It is the basic building block of modern electronics, and the most widely manufactured device in history, with an estimated total of 13 sextillion (1.3 × 1022) MOSFETs manufactured between 1960 and 2018.
A telecommunications network is a collection of terminal nodes in which links are connected so as to enable telecommunication between the terminals. The transmission links connect the nodes together. The nodes use circuit switching, message switching or packet switching to pass the signal through the correct links and nodes to reach the correct destination terminal. Each terminal in the network usually has a unique address so messages or connections can be routed to the correct recipients. The collection of addresses in the network is called the address space. Examples of telecommunications networks include:
Complementary metal–oxide–semiconductor (CMOS), also known as complementary-symmetry metal–oxide–semiconductor (COS-MOS), is a type of MOSFET fabrication process that uses complementary and symmetrical pairs of p-type and n-type MOSFETs for logic functions. CMOS technology is used for constructing integrated circuits (ICs), including microprocessors, microcontrollers, memory chips, and other digital logic circuits. CMOS technology is also used for analog circuits such as image sensors, data converters, RF circuits, and highly integrated transceivers for many types of communication.
Wireless communication is the transfer of information or power between two or more points that are not connected by an electrical conductor. The most common wireless technologies use radio waves. With radio waves distances can be short, such as a few meters for Bluetooth or as far as millions of kilometers for deep-space radio communications. It encompasses various types of fixed, mobile, and portable applications, including two-way radios, cellular telephones, personal digital assistants (PDAs), and wireless networking. Other examples of applications of radio wireless technology include GPS units, garage door openers, wireless computer mouse, keyboards and headsets, headphones, radio receivers, satellite television, broadcast television and cordless telephones. Somewhat less common methods of achieving wireless communications include the use of other electromagnetic wireless technologies, such as light, magnetic, or electric fields or the use of sound.
Consumer electronics or home electronics are electronic equipments intended for everyday use, typically in private homes. Consumer electronics include devices used for entertainment, communications, and home-office activities. In British English, they are often called brown goods by producers and sellers, to distinguish them from "white goods" which are meant for housekeeping tasks, such as washing machines and refrigerators, although nowadays, these would be considered brown goods, some of these being connected to the Internet. In the 2010s, this distinction is not always present in large big box consumer electronics stores, which sell both entertainment, communication, and home office devices and kitchen appliances such as refrigerators.
The history of mobile phones covers mobile communication devices that connect wirelessly to the public switched telephone network.
A computer network is a digital telecommunications network which allows nodes to share resources. In computer networks, computing devices exchange data with each other using connections between nodes. These data links are established over cable media such as wires or optic cables, or wireless media such as Wi-Fi.
A radio frequency power amplifier is a type of electronic amplifier that converts a low-power radio-frequency signal into a higher power signal. Typically, RF power amplifiers drive the antenna of a transmitter. Design goals often include gain, power output, bandwidth, power efficiency, linearity, input and output impedance matching, and heat dissipation.
The following outline is provided as an overview of and topical guide to telecommunication:
Telecommunications engineering is an engineering discipline centered on electrical and computer engineering which seeks to support and enhance telecommunication systems. The work ranges from basic circuit design to strategic mass developments. A telecommunication engineer is responsible for designing and overseeing the installation of telecommunications equipment and facilities, such as complex electronic switching systems, and other plain old telephone service facilities, optical fiber cabling, IP networks, and microwave transmission systems. Telecommunication engineering also overlaps with broadcast engineering.
Edholm's law, proposed by and named after Phil Edholm, refers to the observation that the three categories of telecommunication, namely wireless (mobile), nomadic and wired networks (fixed), are in lockstep and gradually converging. Edholm's law also holds that data rates for these telecommunications categories increase on similar exponential curves, with the slower rates trailing the faster ones by a predictable time lag. Edholm's law predicts that the bandwidth and data rates double every 18 months, which has proven to be true since the 1970s. The trend is evident in the cases of Internet, cellular (mobile), wireless LAN and wireless personal area networks.
In computing, bandwidth is the maximum rate of data transfer across a given path. Bandwidth may be characterized as network bandwidth, data bandwidth, or digital bandwidth.
LDMOS is a planar double-diffused MOSFET used in microwave/RF power amplifiers as well as audio power amplifiers. These transistors are often fabricated on p/p+ silicon epitaxial layers. The fabrication of LDMOS devices mostly involves various ion-implantation and subsequent annealing cycles. As an example, The drift region of this power MOSFET is fabricated using up to three ion implantation sequences in order to achieve the appropriate doping profile needed to withstand high electric fields.
Telecommunications equipment is a hardware which is used for the purposes of telecommunications. Since the 1990s the boundary between telecoms equipment and IT hardware has become blurred as a result of the growth of the internet and its increasing role in the transfer of telecoms data.
Telecommunication is the transmission of signs, signals, messages, words, writings, images and sounds or information of any nature by wire, radio, optical or other electromagnetic systems. Telecommunication occurs when the exchange of information between communication participants includes the use of technology. It is transmitted through a transmission media, such as over physical media, for example, over electrical cable, or via electromagnetic radiation through space such as radio or light. Such transmission paths are often 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 often used in its plural form because it involves many different technologies.
This article details the history of electronic engineering. Chambers Twentieth Century Dictionary (1972) defines electronics as "The science and technology of the conduction of electricity in a vacuum, a gas, or a semiconductor, and devices based thereon".
Mohamed Mohamed Atalla was an Egyptian-American engineer, physical chemist, cryptographer, inventor and entrepreneur. His pioneering work in semiconductor technology laid the foundations for modern electronics. Most importantly, his invention of the MOSFET in 1959, along with his earlier surface passivation and thermal oxidation processes, revolutionized the electronics industry. He is also known as the founder of the data security company Atalla Corporation, founded in 1972, which introduced the first hardware security module and was a pioneer in online security. He received the Stuart Ballantine Medal and was inducted into the National Inventors Hall of Fame for his important contributions to semiconductor technology as well as data security.
These active electronic components, or power semiconductor products, from Siliconix are used to switch and convert power in a wide range of systems, from portable information appliances to the communications infrastructure that enable the Internet. The company's power MOSFETs — tiny solid-state switches, or metal oxide semiconductor field-effect transistors — and power integrated circuits are widely used in cell phones and notebook computers to manage battery power efficiently