1837, American Morse successfully sent telegrams in Washington and Baltimore. 1857, transatlantic submarine telegraph cable completed. 1875 American Bell invented the telephone; 1877 American Edison invented the phonograph. 1887, German Hertz verified electromagnetic waves through experiments. 1889 Italian Marconi successfully filmed the broadcast between Britain and France; 1895, Russian popov and Italian Marconi developed radio receivers at the same time. 1895, French Lumiere brothers premiered their first film in Paris. 190 1 transatlantic cables were successfully laid in the printing age; In the printing era of 19 12, in the sinking of the Titanic, radio saved more than 700 lives. In the printing era of 19 15, the long-distance radio communication between Paris and Washington was successful; 1920s In the printing age, the radio came out. In the printing era of 1920s, Baird, an Englishman, successfully transmitted TV pictures and was known as the inventor of TV.
1926 in the printing era, Beat of England completed the development of TV images in the Royal College of England; The first electronic computer "ENIAC" came out in the printing era of 1946, Moore School of Electronic Engineering, University of Pennsylvania, USA. 1947 in the printing age, Americans were shocked to invent the transistor; In the printing era of 1953, IBM developed "IBM 650" series computers; In the printing era of 1955, the United States issued the first military electronic computer to meet the needs of the great war. In the printing era 1956, American Ampex Company invented the video recorder; In the printing era of 1957, IBM developed the first generation of high-level language "fortran"; The printing age 1958 is an exciting year. This year, Davos discovered the principle of laser. 1960 printing era, the United States made the first generation of minicomputer PDP I；; 1962 in the printing era, the United States launched the first artificial satellite, which opened the era of TV satellite transmission. 1962 in the printing era, American communication satellites successfully communicated with Europe; In the era of network communication 1969, the US military established the ARPANET to prevent communication from being interrupted when it was attacked. In the era of network communication, the United States proposed a global communication network blueprint from 65438 to 0969; In the era of network communication 1970, Intel made subminiature integrated chips; In the era of network communication, American Bill Gates developed the "Basic" language in 1975. In the era of network communication from 65438 to 0977, Apple made the PC "Apple II"; In the era of network communication, the United States proposed to build a high-speed communication network in 1978; Network Communication Era 1979 The research team of the legendary American Ciro Company, led by bob taylor, studied the predecessor of the Internet. In the era of network communication 198 1, Microsoft Corporation of the United States developed "MS-DOS". In the same year, IBM released IBM-PC；; ; In the era of network communication 1983, the U.S. Department of Defense divided ARPANET into military network and civilian network, and gradually expanded to today's Internet. In the era of network communication, CD-ROM appeared 1984, and communication entered a massive era. Apple launched a shopping computer; Network communication era 1988 with the development of communication, virtus has increased dramatically; Network Communication Era 199 1 Motorola, IBM and Apple jointly launched Power-PC Chip Network Communication Era 1993, and the United States announced the construction of information high-speed access plan to integrate computer, telephone and TV media. In the era of network communication 1993, Intel Corporation of the United States developed non-Risc high-performance CPU；. In the era of network communication, the information superhighway was built in Florida from 65438 to 0994. In the era of network communication, Microsoft developed Windows95 at 1995. Integrating network function into PC communication is one of the basic themes of newspaper propaganda, which has the characteristics of true content, detailed and concrete, free and flexible form, diverse forms of expression and vivid language. The types of communication are: character communication, event communication, work communication, character image communication, news story communication, literature communication, theme communication and tourism communication; The most common ones are: character communication and event communication. It is one of the important forms of applied writing research. Communication is a style of reporting typical people, events and experiences with news characteristics in a concrete and vivid way with narrative and description as the main forms of expression. There are many forms of expression, such as general communication, close-ups, sketches, interviews, notes, essays, tours, stories, etc., which can generally be classified as communication. Human beings have a long history of communication. As early as ancient times, people exchanged information through simple language and murals. For thousands of years, people have been using language, symbols, bells and drums, fireworks, bamboo slips and paper books to convey information. Ancient bonfires, flying pigeons and post horses are examples of this. In some countries, there are still some primitive tribes, which still retain the ancient times of beating drums and blowing trumpets. The traffic police's command of sign language and semaphore in navigation is only the result of the further development of ancient communication methods, and the basic aspect of these information transmission depends on human vision and hearing.
/kloc-After the middle of the 9th century, with the development of telegraph and telephone and the discovery of electromagnetic waves, fundamental changes have taken place in the field of human communication, realizing the transmission of information by metal wires and even wireless communication by electromagnetic waves, making the mythical "clairvoyance" and "clairvoyance" become a reality. Since then, human information transmission can be separated from the conventional audio-visual way and use electrical signals as a new carrier, which brings.
Samuel Morse, an American, successfully developed the first electromagnetic telegraph in the world in 1837. He used his own code to convert the information into a series of long or short electrical pulses, which were transmitted to the destination and then converted into the original information. On May 24th, 20438+0844, Morse held the meeting in the Federal Supreme Court of the Capitol.
1864, the British physicist J.c.Maxwel established a set of electromagnetic theories, predicted the existence of electromagnetic waves, and explained that electromagnetic waves and light have the same properties and both travel at the speed of light.
1875, the Scottish youth A.G. Bell invented the world's first telephone, 1876, and he applied for an invention patent. 1878, he conducted the first long-distance telephone experiment between Boston and new york, 300 kilometers away, and achieved success. Later, he established the famous Bell Telephone Company.
1888, the young German physicist H.R. Hertz conducted a series of experiments with radio circuits and discovered the existence of electromagnetic waves. He proved Maxwell's electromagnetic theory through experiments. This experiment caused a sensation in the whole scientific community and became an important milestone in the history of modern science and technology, which led to the birth of radio and the development of electronic technology.
The discovery of electromagnetic waves had a great influence. In less than six years, Russian popov and Italian Marconi invented the wireless telegraph respectively, and realized the radio transmission of information. Other radio technologies have mushroomed. 1904, British electrical engineer Fleming invented the diode. 1906, American physicist Fessenden successfully developed radio broadcasting. 1907, the American physicist Dresden invented the vacuum transistor. American electrical engineer Armstrong invented the superheterodyne receiver by using electronic devices. American radio expert Conrad established the world's first commercial radio station in Pittsburgh on 1920. Since then, broadcasting has flourished all over the world, and it has become a convenient way for people to understand current events. 1924, the first short-wave communication line was established between nauen and Buenos Aires, 1933, the first line between Britain and France was established by Clarville, a Frenchman.
The discovery of electromagnetic waves has also promoted the rapid development of image communication technology. 1922 16-year-old American middle school student Philo Farnsworth designed the first schematic diagram of TV fax. 1929 applied for an invention patent and was ruled as the first person to invent TV. Zwojin of Westinghouse Electric Company invented the photoelectric picture tube in 1928, and cooperated with the engineering teacher gas. TV transmission and electronic scanning transmission are realized. 1938+0935 established a TV station in Empire State Building, New York, USA, and the TV program was successfully sent to 70 kilometers away the following year. 1938+0938, Volgin made the first TV camera that meets the practical requirements. After continuous exploration and improvement, 1945, American radio company made the world's first full-tube color TV set according to the working principle of three primary colors. Until 1946, American Ross Weimar invented the high-sensitivity camera tube, and in the same year, Japanese professor Ba Ben solved the receiving antenna problem of household TV sets. Since then, some countries have successively established ultrashort wave relay stations, and television has rapidly spread.
Image fax is also an important communication mode. Since 1925, the first practical fax machine was developed by American radio company, and the fax technology has been continuously innovated. Before 1972, this technology was mainly used in news, publishing, meteorology, broadcasting and other industries. From 1972 to 1980, fax technology has completed the transformation from analog to digital, from mechanical scanning to electronic scanning, and from low speed to high speed. In addition to transmitting meteorological maps, press releases, photos and satellite cloud pictures instead of telegrams, it has also been applied in medical treatment, library management, information consultation, financial data, electronic post and so on. After 1980, fax technology was transformed into an integrated processing terminal, which not only undertakes communication tasks, but also has the ability of image processing and data processing, thus becoming an integrated processing terminal. Electrostatic copiers, tape recorders, radars and lasers are all important inventions in the history of information technology.
In addition, remote control, telemetry and remote sensing technologies are also very important technologies. Remote control is a technology that uses communication lines to control remote controlled objects, which is applied in electrical industry, oil pipeline, chemical industry, military and aerospace industry. Telemetry is a measurement technology, which converts the measured physical quantities to a distant place, such as voltage, current, air pressure, temperature, flow and so on. , converted into electricity, transmitted to observation points through communication lines, and applied to meteorological, military, aerospace and other industries. Remote sensing is a comprehensive measurement technology, which uses sensors to receive electromagnetic wave information radiated by high-altitude or distant objects, and prompts the nature, shape and changing trend of the measured objects through processed or recognizable images or recording tapes used by computers. It is mainly used in meteorology, military affairs, aerospace and other fields.
With the rapid development of electronic technology, the computing tools urgently needed by military and scientific research have also been greatly improved. 1946, eckert and Moses of the University of Pennsylvania developed the world's first electronic computer. The innovation of electronic component materials further promotes the development of electronic computers in the direction of miniaturization, high precision and high reliability. In the 1940s, scientists discovered semiconductor materials and used them to make transistors. Replaced the vacuum tube. 1948, shockley, Badin and Bratin of Bell Laboratories invented transistors, so transistor radios, transistor TVs and transistor computers quickly replaced various vacuum tube products. 1959, kilby and Noyce of the United States invented integrated circuits, and microelectronics technology was born. 1967, LSI was born. More than 65,438+0,000 transistor circuits can be integrated on a silicon wafer the size of a grain of rice. 1977, American and Japanese scientists made VLSI, and integrated 1.3 million transistors on a 30-square-millimeter silicon wafer. Microelectronics technology has greatly promoted the upgrading of electronic computers, showing unprecedented information processing functions and becoming an important symbol of modern high technology.
In order to solve the problem of resource sharing, a single computer has rapidly developed into computer networking, realizing data communication and data sharing between computers. Communication media has developed from ordinary wires and coaxial cables to twisted pair, optical fiber lines and optical cables. The input and output devices of electronic computers have also developed rapidly. Scanner, plotter, audio and video equipment, etc. Make the computer more powerful and can handle more complex problems. The rise of multimedia technology in the late 1980s enabled computers to comprehensively handle various forms of information, such as words, sounds, images and movies, and increasingly became the most important and basic tool for information processing.
At this point, we can preliminarily think that information technology (IT) is a comprehensive technology based on microelectronics and photoelectric technology, supported by computer and communication technology, and with information processing technology as the theme. The close combination of electronic computer and communication technology marks the arrival of the digital information era and the end of the history of communication development.
line telecommunications
American Morse (F.B.Morse): The telegram is about 5 kilometers (dots, dashes, spaces → letters and numbers);
American Bell (A.G.Bell): patented telephone (electric signal → voice);
Pubin, USA: communication cable;
1972 Japan: data communication and fax communication services of public communication network;
USA: Publishing Bell Data Network, UK: Image Information Service Experiment;
Modern communication systems use some centralized exchange facilities → complex information networks.
→ "exchange function" → realize signal transmission between any two points.
wireless communication
Maxwell, England, 1864: hypothesis of electromagnetic wave;
1888 H Hz: confirm the existence of electromagnetic wave;
1895 Marconi, Italy: wireless communication, the transmission distance is only a few hundred meters;
Italy Marconi 190 1: Wireless communication across the Atlantic;
1938 French ribbon: PCM mode;
1940 CBS: color TV experiment broadcast;
195 1 American CBS: official broadcast of color TV;
Modern wireless communication is spread all over the world and leads to the universe.
Such as GPS, its accuracy can reach tens of meters.
I wonder if there will be more development of communication technology in the future.