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| title | chunk | source | category | tags | date_saved | instance |
|---|---|---|---|---|---|---|
| History of telecommunication | 5/5 | https://en.wikipedia.org/wiki/History_of_telecommunication | reference | science, encyclopedia | 2026-05-05T04:00:29.329747+00:00 | kb-cron |
MOS technology was initially overlooked by Bell because they did not find it practical for analog telephone applications. MOS technology eventually became practical for telephone applications with the MOS mixed-signal integrated circuit, which combines analog and digital signal processing on a single chip, developed by former Bell engineer David A. Hodges with Paul R. Gray at UC Berkeley in the early 1970s. In 1974, Hodges and Gray worked with R.E. Suarez to develop MOS switched capacitor (SC) circuit technology, which they used to develop the digital-to-analog converter (DAC) chip, using MOSFETs and MOS capacitors for data conversion. This was followed by the analog-to-digital converter (ADC) chip, developed by Gray and J. McCreary in 1975. MOS SC circuits led to the development of PCM codec-filter chips in the late 1970s. The silicon-gate CMOS (complementary MOS) PCM codec-filter chip, developed by Hodges and W.C. Black in 1980, has since been the industry standard for digital telephony. By the 1990s, telecommunication networks such as the public switched telephone network (PSTN) had been largely digitized with very-large-scale integration (VLSI) CMOS PCM codec-filters, widely used in electronic switching systems for telephone exchanges and data transmission applications.
=== Wireless revolution ===
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. Hitachi developed the vertical power MOSFET in 1969, but it was not until Ragle perfected the concept in 1976 that the power MOSFET became practical. In 1977 Hitachi announce a planar type of DMOS that was practical for audio power output stages. 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).
== Timeline ==
=== Visual, auditory and ancillary methods (non-electrical) === Prehistoric: Fires, beacons, smoke signals, communication drums, horns 6th century BCE: Mail 5th century BCE: Pigeon post 4th century BCE: Hydraulic semaphores 15th century CE: Maritime flag semaphores 1672: First experimental acoustic (mechanical) telephone 1790: Semaphore lines (optical telegraphs) 1867: Signal lamps 1877: Acoustic phonograph
=== Basic electrical signals === 1838: Electrical telegraph. See: Telegraph history 1830s: Beginning of attempts to develop "wireless telegraphy", systems using some form of ground, water, air or other media for conduction to eliminate the need for conducting wires. 1858: First trans-Atlantic telegraph cable 1876: Telephone. See: Invention of the telephone, History of the telephone, Timeline of the telephone 1880: Telephony via lightbeam photophones
=== Advanced electrical and electronic signals === 1896: First practical wireless telegraphy systems based on Radio. See: History of radio. 1900: first television displayed only black and white images. Over the next decades, colour television were invented, showing images that were clearer and in full colour. 1914: First North American transcontinental telephone calling 1927: Television. See: History of television 1927: First commercial radio-telephone service, U.K.–U.S. 1930: First experimental videophones 1934: First commercial radio-telephone service, U.S.–Japan 1936: World's first public videophone network 1946: Limited capacity Mobile Telephone Service for automobiles 1947: First working transistor (see History of the transistor) 1950: Semiconductor era begins 1956: Transatlantic telephone cable 1962: Commercial telecommunications satellite 1964: Fiber optical telecommunications 1965: First North American public videophone network 1969: Computer networking 1973: First modern-era mobile (cellular) phone 1974: Internet (see History of Internet) 1979: INMARSAT ship-to-shore satellite communications 1981: First mobile (cellular) phone network 1982: SMTP email 1998: Mobile satellite hand-held phones 2003: VoIP Internet Telephony
== See also ==
History of the Internet History of podcasting History of radio History of television History of the telephone History of videotelephony Information Age Information revolution Optical communication Outline of telecommunication
== References ==
=== Sources === Wenzlhuemer, Roland. Connecting the Nineteenth-Century World: The Telegraph and Globalization. Cambridge University Press, 2013. ISBN 9781107025288
== Further reading == Hilmes, Michele. Network Nations: A Transnational History of American and British Broadcasting (2011) John, Richard. Network Nation: Inventing American Telecommunications (Harvard U.P. 2010), emphasis on telephone Noll, Michael. The Evolution of Media, 2007, Rowman & Littlefield Poe, Marshall T. A History of Communications: Media and Society From the Evolution of Speech to the Internet (Cambridge University Press; 2011) 352 pages; Documents how successive forms of communication are embraced and, in turn, foment change in social institutions. Wheen, Andrew. DOT-DASH TO DOT.COM: How Modern Telecommunications Evolved from the Telegraph to the Internet (Springer, 2011) Wu, Tim. The Master Switch: The Rise and Fall of Information Empires (2010) Lundy, Bert. Telegraph, Telephone and Wireless: How Telecom Changed the World (2008)
== External links == Katz, Randy H., "History of Communications Infrastructures" Archived 2011-09-30 at the Wayback Machine, Electrical Engineering and Computer Science Department (EECS) Department, University of California, Berkeley. International Telecommunication Union Aronsson's Telecom History Timeline From the Thurn & Taxis to the Phone Book of the World - 730 years of Telecom History Telecommunications History Group Virtual Museum Telecommunications History Germany Telecommunications History France