electronics

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This entry is made by Compilation and application of scientific encyclopedia entries of "Science Popularization China" to examine.

Electronics is a science and technology with application as its main purpose. It mainly studies the characteristics and behavior of electrons, as well as the physics of electronic devices. Electronic technology is a science that applies the principles of electronics to design and manufacture circuits and electronic devices to solve practical problems. Modern electronics has become a subject attracting worldwide attention.^[1]

Chinese name: electronics
Foreign name: electronics
Discipline: Physics 、 Mechanical and other interdisciplinary subjects

Core: Electronic motion, electromagnetic wave
Application: Electronic tubes, integrated circuits, etc
Elementary particle: Electronics

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Electronics is based on the movement of electrons and electromagnetic wave And the research and utilization of their interactions. As a new means of information operation, it has developed vigorously.

Electronics involves many scientific categories, including, Physics 、 Chemistry 、 mathematics 、 material science Etc. Electronic technology is the science of applying the principles of electronics to design and manufacture circuits and electronic devices to solve practical problems.

The electron is a major member of the basic particle family. The static mass of the electron is 9.10953 × 10-28g, which is hydrogen atom 1/1836 of the mass. The electron charge is 1.602189 × 10-19 Coulomb Is negatively charged. There are opposites of electrons in the universe - positron , but its service life is very short and generally does not exist. proton The charge is equal to the absolute value of the electronic charge positive charge , Yes hydrogen atom The main component of quality. Under normal circumstances, atoms contain the same amount of electrons and protons, which are not apparent to the outside. But when it captures or loses electrons, it shows external electricity, called ions. Ions also occupy a certain position in electronics, but they are far less widely used than electrons. Accompanied by electric charge electric field , the effect of electric field on electric charge. The movement of electric charge generates current, which is accompanied by magnetic field The effect of magnetic field on the force of magnet or current. When the current changes, the surrounding electric and magnetic fields will also change. This change carries energy in the form of wave and propagates outward at a certain speed. This wave is called electromagnetic wave. The faster the current changes, the shorter the electromagnetic wave length generated, but the propagation speed remains unchanged. Electromagnetic wave vacuum The propagation speed in is 299792.46 kilometers per second. electromagnetic field And electromagnetic waves can also interact with charged particles to generate energy transformation. Both theory and practice have proved that light waves X-ray 、 Gamma ray They are all electromagnetic waves, but their wavelengths are different. Electron and electromagnetic wave have wave and particle duality; In the electronic Movement speed Extremely high and extremely short electromagnetic wave length, with significant wave particle duality.

After about a century of non-stop exploration and development, modern electronics has developed into one of the most eye-catching professions and disciplines in the contemporary era.

History and Application

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Electronics has a history of only about 100 years since its birth electromagnetics and Electrotechnics Developed on the basis of. Before the birth of electronics, human beings Electromagnetic phenomenon The research of has been quite in-depth. A series of physical laws have been established, such as Coulomb's law 、 Ampere's law 、 Ohm's law 、 Lenz's law 、 Faraday's law of electromagnetic induction Etc. britain J. C. Maxwell Maxwell, a complete theory of electromagnetism, has been established based on the achievements of previous research on electromagnetism equation And theoretically predicted the existence of electromagnetic waves.^[2] At the same time, people electromagnetics The use of cable telegraphy and telephone has also reached a certain level. Cable telegraphy and telephone have been invented one after another, and there are telegraph and telephone lines across the American continent and transatlantic Submarine cable 。 U.S.A T. A. Edison Invented Incandescent lamp 。 All these have prepared sufficient conditions for the birth of electronics.

The two major historical events that marked the birth of electronics are Edison effect The discovery of electromagnetic wave and the verification experiment about the existence of electromagnetic wave. In 1883, Edison Is committed to extending Carbon filament During the service life of incandescent lamps, it was accidentally discovered that there was a current flowing between the filament and the electrode with positive voltage, and when the electrode was negative, there was no current, which was the Edison effect. This discovery led to Electronic tube Invention of.

1887, Germany H. R. Hz An experiment was carried out. He used a spark gap to excite a ring antenna and another ring antenna with a gap to receive, which confirmed Maxwell's prediction about the existence of electromagnetic waves. This important experiment led to the later invention of wireless telegraphy.

Many significant achievements have been made in the development of electronics.

Radiotelegraph Before the birth of electronics, S. Morse invented and built the telegraph line in 1837, hertz The experiment set up a bridge from "wired" to "wireless".

In 1895, G. Marconi of Italy Hertz experiment On the basis of the above, the wireless telegraph transmission experiment with a distance of 2.5 km has been successfully carried out.

1896, Russia А. С. Popov He also independently conducted a similar experiment at a distance of about 250 meters. The first message he sent was "Hertz". In the following years, Marconi carried out a series of fruitful work in Britain, making the transmission distance of wireless telegraphy continue to extend.

In 1899, across English channel Successful test;

In 1901, the test of 3200km across the Atlantic Ocean was successful. Marconi, with his development in wireless telegraphy and the radio communication Achievements in career Nobel Prize Physics Award.

The invention of wireless telegraphy is the first great achievement of human beings in using electromagnetic waves, and electronics began a very prosperous period of research and use of electromagnetic waves.

Electronic tube

Electronic tube 　 Edison Although I found Thermionic emission Effect (i.e Edison effect ）However, he did not realize the significance of this effect and was not clear about its mechanism.

1897, England J. J. Thomson It reveals that Charged particle The Edison effect is a hot electron emission phenomenon.

1904, England J. A. Fleming He was the first to put the Edison effect into practice and invented the diode tube. The invention of the diode tube provides a sensitive and reliable detector 。

electronics

In 1906, the United States 50. De Forrest The invention of triode electron tube with amplification capability was a booming wireless Telegraph communication The enterprise provides an extremely useful device. After the triode Tetrode 、 Pentode , more polar electronic tubes and composite tubes, forming Receiver tube 、 launching tube , low-frequency tube, high-frequency tube, microwave tube and subminiature tube.

Electronic tube It is the first generation of electronic devices transistor In nearly half a century before the invention, the electronic tube was almost the only available electronic device in all kinds of electronic equipment. Many subsequent achievements in electronics, such as television radar The invention of computers is inseparable from electronic tubes. In the modern era when solid state electronics is very prosperous High-power electron tube (especially microwave power tubes) and Electron beam tube Represented by Vacuum electronics It is also still an active field.^[1]

Radio and TV

1876, USA A. G. Bell At the 100th anniversary of the founding of the United States, he displayed his invention of the wired telephone. Since then, wired phones have quickly become popular. G. Marconi The invention of wireless telegraphy contributed to wireless telephone and radio broadcast The occurrence of.

In 1906, the United States R. A. Fessenden He conducted a very meaningful experiment with 50 Kilohertz frequency alternator As transmitter Microphones Directly string in the antenna to realize modulation, which makes the radio operator on the Atlantic ship hear him from boston The music broadcast was the first of the invention of radio broadcasting.

In 1916, G D. Sanov first proposed the idea of radio broadcasting to the public, but because the First World War Burst but failed to achieve.

In 1919, the first regular broadcast of language and music Radio station Built in England. The following year, in the United States Pittsburgh Another radio station was built in the city. thereafter, radio broadcast The cause is popularized worldwide Medium wave Expand to short wave ultrashort wave , from amplitude modulation Expand to frequency modulation 、 Pulse modulation The satellite live broadcast has also been realized.

The invention of television can be traced back to 1884 P G. paul Nipkow about Mechanically scanned television The assumption of. It is the British J L. Baird 。

In 1927, he successfully transmitted the image from London to a ship in the Atlantic Ocean by telephone line. However, this is not a modern type of all electronic television. The first person who made practical contributions to all electronic television is V K. Zvorekin 。 In 1923 and 1924, he successively invented the camera tube and Kinescope 。

In 1931, he assembled the world's first fully electronic television system. In the following years, after repeated improvements, about the end of the 1930s, Britain and the United States began experimental television broadcasting. the Second World War Later, television broadcasting was gradually popularized in various countries.

The invention of radio and television not only makes human cultural life more colorful, but also provides a public information medium for human beings.^[3]

radar

radar Objects, especially metal objects (such as ships), have the ability to reflect electromagnetic waves hertz , Marconi Popov The times have long been known. Before the invention of radar Impulse radio Device measurement the ionosphere High level work has been carried out for many years. On the eve of World War II, when aircraft became the main offensive weapon, Britain, the United States, Germany, France and other countries all invested more manpower to develop a class of devices that could alert aircraft early.

1936, England R. A. Watson Watt The designed warning radar was first put into operation. It was set up on the east coast of Britain, effectively guarding against bombers from Germany.

In 1938, the United States developed the first artillery control radar that can command artillery firing, greatly improving the hit rate of artillery.

In 1940, there was a Multicavity magnetron , the next year, the first Microwave radar Successful development.

In 1944, we were able to automatic tracking The radar of the aircraft has been successfully developed.

In 1945, moving targets that can eliminate background interference and display moving targets display technique The invention of radar More perfect. Throughout the Second World War, radar became one of the most active parts of electronics. Proximity fuze It also belongs to radar nature, and it has increased the artillery power hundreds of times.

electronic computer

electronic computer It is an invention of computing tools. from Ancient China Of Calculation And abacus to the 16th century Western Calculating rule And gear computer, from mechanical computer to electronic computer, from manual calculation to automatic calculation, from decimal system reach Binary It is a process of gradual development. The application of electronic computers is more and more extensive, from scientific computing to transaction management process control , information retrieval, artificial intelligence and many other fields have had a tremendous impact on human production and life.

transistor

Germanium transistor with golden yellow shell^[4]

transistor : legitimate Electronic tube In its heyday, the United States Bell Laboratories The physicists of Solid state device Research.

In 1948, Bell Laboratories announced that J Badin 、W.H. Bratton And W B. Shockley Develop crystals triode 。 The early transistor was a point touch type, which was difficult to manufacture and had poor stability, but it was a sign of the times after all.

Invented by D. Sparks of Bell Laboratories in 1957 Surface junction transistor , which overcomes the shortcomings of the point contact transistor and consolidates the status of the transistor that has not been published for a long time. Later, due to the progress in material technology, Shockley's early ideas Field effect transistor It is also realized.

The invention of transistor pushed electronics to a new stage. Many achievements in electronics in the future, such as integrated circuits, microprocessors and microcomputers, have come from transistor Developed from.^[4]

Integrated circuit

Integrated NAND gate circuit 74LS01

In 1958, the United States Texas The instrument company announced the emergence of an integrated oscillator transistor It is integrated on a silicon chip with resistors and capacitors to form a basically complete monolithic functional circuit.

1961, USA Fairy Boy The company announced an integrated trigger. Since then, integrated circuits have developed rapidly. Digital integrated circuit From small scale to medium scale, large scale, even to super scale, Integration It is getting higher and higher Mainframe It was miniaturized and entered the era of microcomputer. meanwhile, Analog integrated circuit It has also developed.

The invention of integrated circuit created a new situation of integrating electronic devices and some electronic components, which changed the traditional concept of electronic devices. This new packaged device has small volume and power consumption, independent circuit functions, and even system functions. monolithic Microwave integrated circuit It has also entered the production stage. The invention of integrated circuit brought electronics into microelectronics The period is a major leap in the development of electronics.

satellite communication

In 1957, the Soviet Union launched Artificial earth satellite Success announced the arrival of the space age.

In 1958, the United States successfully launched the low orbit "Skoll" satellite, which was the first test satellite for communication.

In 1962, the United States launched Middle track Of Communication satellite "Telstar" - I.

In 1963, the United States launched the "Xinkang" - II into the Synchronous orbit , become the first fixed point Synchronous communication satellite 。

In 1964, with the help of fixed-point synchronous communication satellites, communication and television transmission were realized for the first time in the United States, Europe and Africa.

In 1965, the first commercial fixed point Geostationary satellite Put into operation.

By 1969, there had been fixed point synchronous communication satellites over the Atlantic, Pacific and Indian Oceans, and satellite earth stations had spread all over the world. These satellite earth stations were connected to the communication network in their own countries or regions. satellite communication After 10 years of development, it has finally become mature.

Use fixed point Synchronous communication satellite As Repeater station , intercontinental information transfer It provides a stable and reliable means, and also solves the domestic communication problems of countries with vast territory. The success of satellite communication is not only communication technology, but also another leap in electronics.

Exploitation and utilization

Optical frequency Development and utilization of An important aspect of the development of electronics is Electromagnetic spectrum The expansion of utilization, especially the development and utilization of optical frequency band (including infrared and ultraviolet). Maxwell's classic Electromagnetic theory Has already clarified the light Electromagnetic essence 。 People's understanding and utilization of light were long before the birth of electronics. But, in Laser Before the invention, people were mainly involved in the right and wrong coherent light 。

1954, USA C. H. Townes The first set in the world is developed with cooled ammonia as working material Maser 。 Later, the Soviet Union Н. Г. Basov and А. М Prokhorov A maser using cesium fluoride as working material has also been developed.

In 1958, Townes And A 50. Xiao Luo will microwave Stimulated radiation The principle of the infrared spectrum is extended to the infrared spectrum and the optical spectrum.

In 1960, T H. Meiman developed the first laser Ruby Pulsed laser 。 Less than a year later, the first continuous laser - He Ne laser Successful development. Since then Electromagnetic spectrum , from Radio band It has been extended to the optical frequency band, so that the already crowded radio frequency band has been alleviated.

The laser was invented by D. Gable in 1946 holographic Photography technology has gained new vitality, and has become a high density and large capacity Information storage technology Laid the foundation. The advent of lasers has also led to the emergence of high-capacity optical fiber communication, making communication technology continue satellite communication Then another leap took place, which is another major progress.

Basic Sciences

A series of great achievements in electronics in practice are inseparable from its achievements in applied basic science.

In the 1920s and 1930s carrier , long-distance and audio communication, people study circuit networks Analog filter 、 Transmission line , hearing and sound, and made significant progress.

stay information theory and Communication Theory On the other hand, the measurement of information and the effectiveness and reliability of information transmission (i.e. communication) are the main problems in this regard.

In 1924, H. Nyquist first proved that the rate of information transmission Channel bandwidth Is proportional.

In 1928, R.V.L. Hartley proved that, information content With information length logarithm Is proportional. It can be said that this is a pioneering work on information measurement.

1948, C.E shannon The study of information is based on statistics. He introduced Information entropy It solves the problem of information measurement. His more important achievement is the ability to transmit information limit Formulas, about Source and channel coding The theorem of, and about Information rate distortion function The concept of. Xiannong became information theory The founder of. On the other hand,

In 1942, D.O. North proposed the best wave filter Concept of;

In 1948, В. А Kojiernikov founded the theory of optimal receiver;

In 1950, P.M. Utwald proposed ambiguity function It has become a modern radar Detection theory The pioneer of.

Control and system theory The achievements in this field have had a great impact on the development of modern electronics. From the perspective of electronics, the following early facts should be mentioned in particular: although J. Watt had already invented negative feedback Speed of Modulator In 1928, H. Blake proposed the concept of negative feedback from the perspective of circuit;

In 1932, H. Nyquist applied this principle to Circuit stability analysis;

In 1942, N. Weiner proposed Stationary random signal The theory of smoothing, filtering and prediction;

In 1949, N. Weiner made a high generalization of communication and control problems in machines and animals, and founded cybernetics This new subject. In the late 1950s, state variable The introduction of the concept has made a great leap in control and system theory.

In 1957, R. Berman founded dynamic programming Theory;

1958, Л. С Pontryagin Proposed Maximum principle ；

In 1960, R. Kalman extended the Wiener problem to the multivariable, non-stationary case and gave the Recursive He also proposed the concepts of controllability and observability. The achievements made in the history of electronics are manifold, and each branch or discipline has its own achievements in applied basic science. Theory and practice, in turn, complement each other and continue to improve, pushing the entire electronics to new stages.

Domestic progress

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China has a long history country with an ancient civilization , has a splendid culture. However, after the Opium War in 1840, China gradually became Semi colony A semi feudal country. China is not only oppressed politically, but also exploited economically. It is also very backward in science and education. This situation lasted until the founding of the People's Republic of China in 1949. In the first half of the century electromagnetics and Electrotechnics In the period of vigorous development in the West and the birth of electronics; The second half of this period was the period when electronics grew rapidly and made brilliant achievements in the West. During this period, China was basically outside the torrent of electronics development. The People's Republic of China Before its establishment, only a few repair and equipment factories and a few universities were able to train a small number of telecommunications talents.^[5]

The creation and development of electronics and electronic industry in China began after the founding of the People's Republic of China.

electronics

1949~1952 was the period of economic recovery in China. The main achievements of this period are as follows: the State has established the Telecommunications Industry Administration Bureau to lead the country's telecommunications industry in a unified manner; Several factories that were taken over were transformed, and a batch of radio stations and military equipment were soon produced walkie-talkie For the first time in Chinese history Electronic tube ； A number of electronics science and technology workers have returned from overseas to participate in national construction.

From 1953 to 1957, China The first five-year plan Period. During this period, the main achievements were as follows: a number of backbone enterprises focusing on component devices, communications and radars were built, and a number of broadcasting equipment, communications radios and military radars were developed and produced; Radio departments have been set up in more than ten colleges and universities, and professional research institutes and research institutes have been established; For the first time, a twelve year plan for the development of electronic science was formulated.

The main achievements from 1958 to 1965 are: Atomic bomb And missiles, as well as the electronic supporting works required for the test; Developed and produced a batch of military radar Radio stations and other communication equipment; A 1000 kilowatt medium wave broadcasting transmitting station, a 10 channel television center and a 10 kilowatt black-and-white television station have been built; The Research Institute of Posts and Telecommunications, the Research Institute of Electronics Industry and their affiliated research institutions have been established.

1966-1976 was a turbulent decade. China's progress under extremely difficult conditions mainly included: the first man-made earth satellite was successfully launched; First set Integrated circuit computer Successful development; The earth station designed and manufactured by ourselves has been completed; Huge 25m antenna Tracking radar Put into use; The first giant Phased array radar Run in.

Since 1977, China's electronics has entered a new era of revitalization and has achieved many significant achievements. The representative achievements are: successfully launched an experimental fixed point communication synchronous satellite; A national satellite TT&C network has been established; Developed ten million times Vector computer And 100 million computers; Developed into 16000 bits Random access memory and 8-bit microprocessor ; Beijing Shanghai Hangzhou 1800 Road Coaxial cable communication System; Optical fiber communication system It has been incorporated into the local telephone network in Shanghai, Tianjin and Wuhan, reaching the practical stage; A national television network, television transmitting stations and differential turntables have been initially built, with a total of more than 5600; stay National Science and Technology Commission Under the leadership of Electronic Science and Technology Ten year plan of.

Discipline system

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Modern electronics is a huge specialty and Discipline system There are many branches in this system. They are organically combined to form a unified whole of electronics. These branches can be divided into four categories according to their nature: systems and large system technologies; Basic theory And basic technology; Elements, devices Materials and process ； Cross discipline and discipline. Modern electronics, like a big tree with luxuriant branches and leaves, is deeply rooted in applied physics, applied chemistry, applied mathematics, etc Basic discipline In the fertile soil.^[6]

System technology

Branches of this category include: communication, radio, television, radar, navigation electronic countermeasure , computer, energy Electronic system , and integrating multiple system technologies Large electronic system 。 Its common feature is to realize the function with one or more social and military applications by means of electronics.

signal communication It is the principle, technology and system to realize the information transmission from point to point (person to person, person to machine or machine to machine) by means of electronics. Broadcasting is the principle, technology and system of broadcasting language, music, moving and static images and words to the public, and receiving, recording and playing them by the public. Television is the principle, technology and system of capturing, transmitting, reproducing, broadcasting, receiving, recording and playing images, characters and accompanying sounds. radar Is to use objects to Scattering phenomenon The principle, technology and system for discovering aircraft, missiles, ships and other targets and obtaining such target information. remote sensing The technology is mainly to use the radiation electromagnetic waves of ground objects and clouds in the air to observe the phenomena on the ground and in the atmosphere, so as to obtain useful information on geography, landform, geology, vegetation, hydrology, meteorology, etc., which can also be used for military purposes. remote sensing technique It can also be used on the ground. Navigation is the principle, technology and system that determines the position of ships, aircraft, vehicles, etc. and guides them to their destination by means of electronics. electronic countermeasure It is the principle, technology and system of reconnaissance and jamming conducted by both hostile parties by electronic means. Measurement and monitoring systems are not only widely used Electronic Science and Technology Moreover, electronic measurement and detection technology is also widely used in all walks of life, including electricity and non electricity measurement.

Theory and technology

Branches of this category include: electronic circuits and network analysis , microwave, antenna Radio wave propagation , measurement, power supply, display technology, signal processing, information theory Automatic control principle 、 reliability theory Etc. They are various technical means or basic theories required to form functional electronic systems.

Electronic circuits and networks are functional electronic units composed of electronic components and electronic devices. Electronic circuits are linear, nonlinear, analog pulse It can realize filtering, frequency balance, oscillation, amplification, modulation, frequency conversion, pulse forming, switching, shifting, memory, counting and other functions. Microwave technology is about decimeter wave, centimeter wave Millimeter wave The theory and technology of transmission, radiation, measurement and application, etc. The antenna is bound to Transmission line Internal electromagnetism Can be converted to specified Space radiation The theory, technology and device of electromagnetic wave or reverse process. Radio wave propagation It's about electromagnetic waves troposphere 、 the ionosphere Absorption, reflection, refraction diffraction The theory, method and experimental research. Measurement refers to Electromagnetic spectrum Measurement of upper electromagnetic parameters, including measurement of basic parameters of electronic components, devices, materials, circuits and electronic devices Electronic signal Of Characteristic parameter and Electromagnetic energy The measurement of network parameters and the theory, technology and devices related to these measurements.^[2]

The power supply is used to convert chemical energy, thermal energy, nuclear energy, solar energy, AC power, DC power, high-frequency energy, microwave energy, ultrasonic energy, laser energy, etc. electronically for various purposes.

Display technology is the technology that provides information to the information receiver in the form of text, table, graph, etc., including static and dynamic. Signal processing refers to the theory and technology of processing such as filtering, smoothing, compression, transformation and reconstruction of electrical signals such as language, image, radar or other electrical non electrical signals, as well as the application of these theories and technologies in electronic and non electronic fields. The study of information measure The general theory of coding, transmission and processing is a general theory of generalized communication systems. Automatic control is to make Controlled object Reach specified state Or the theory and technology of predetermined function. Its theoretical part has gradually risen to cybernetics and Systems Engineering Theory , its technical part is combined with electronic technology to form automatic control system 。 reliability theory It is related to electronic components, devices, components, electronic devices, and even electronic systems or large System reliability And various concrete methods to improve reliability technical method 。

Devices and processes

The main sub disciplines in this category are: Solid state electronic device And integrated circuit Vacuum electronics Electronic components, electronic materials and relevant production technologies. This kind of sub discipline can be said to be the material basis of electronics.

Semiconductor and integrated circuit is a science and technology to study and utilize semiconductor properties, including semiconductor physics, semiconductor technology Semiconductor discrete device And various integrated circuit devices. Vacuum electronics is a science and technology that studies and utilizes the interaction laws of charged particles (electrons, ions) with fields and substances when moving in vacuum or gas, including electronic physics Electronic tube Technology and various types of electronic tubes. Electronic components constitute electronic equipment Basic unit , usually divided into Active element and Passive component Two types. However, electronic components generally refer to passive components. Electronic material is a science and technology to study various materials for preparing electronic components and devices, including general metal materials, high-energy semiconductor material , dielectric materials, ceramic materials magnetic material , polymer materials Ferroelectric material Etc. Production technology includes various mechanical, electrical and electronic production processes and equipment, such as vacuum equipment electron beam And Ion beam processing Equipment, heating equipment Welding equipment Purification equipment, routine test equipment, etc.

Discipline

Electronics and other disciplines intersect and infiltrate, and many new branches have formed. This category mainly includes: Quantum electronics 、 Nuclear electronics 、 Space electronics , biological and medical electronics Radio astronomy And Radar astronomy Etc.

quantum Electronics is the use of quantum systems within matter energy level Inter Stimulated radiation Phenomenon, amplifying or generating coherent electromagnetic waves, and studying the application of this process. Traditionally, laser technology is also the main content of quantum electronics.

Major Research in Nuclear Electronics Nuclear science Nuclear technology and high-energy physics experiments nuclear radiation and particle Detection electronics technology, research nuclear explosion And the impact of outer space radiation on electronic systems, and radiation resistance Reinforcement technology Etc.

Space electronics is the combination of electronics and Space science and technology The combination of.

Biology and medical electronics is not only the combination of electronics, biology and medicine, but also the application of electronics in biology and medicine.

Electromechanical Engineering

Various electronic equipment, devices, components and devices contain a lot of mechanical technology. This mechanical technology must meet the unique requirements of electronic technology, which is different from the general mechanical engineering 。^[7]

Development application

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Electronics is one of the fast developing subjects. It took 44 years for electronic devices from the invention of the electron tube to the invention of the transistor, while it only took 10 years for the development of the transistor to the integrated circuit. After the advent of integrated circuit, it has developed from small-scale integration to medium scale integration and large-scale integration, and then to very large-scale integration, and there are microprocessors from unit, 4-bit to 32-bit.

electronics

Communication technology has also experienced many epoch-making advances. From overhead open wire before the birth of electronics to the early days of electronics radio ； From long, medium and short wave to ultra short wave microwave , and then expand to infrared and visible light Frequency band. meanwhile, Ultralong wave It has also been applied; from microwave Relay to coaxial cable, up to modern synchronous satellite relay, up to the nearest Optical fiber communication 。 Multi channel communication In the case of telephone, one channel is available Wanlu Analog telephones and thousands of digital telephones. The scope of communication is also expanding, from domestic to international, from intercontinental to global, from Near earth space Develop to interstellar deep space 。

military radar Its operating range has increased by 2-3 orders of magnitude. The maximum distance for non cooperative targets without balise can reach tens of thousands of kilometers, and for cooperative targets with balise can reach tens of millions of kilometers. Almost all orbital targets around the earth have been placed radar Under the surveillance of. The measurement accuracy of the radar has also improved by 2-3 orders of magnitude. The ranging accuracy of the precision tracking radar has reached the meter order of magnitude, and the angle measurement accuracy has reached the milliarc order of magnitude. The application scope of radar has expanded from military to civil departments such as meteorology, surveying and mapping, civil aviation, land and water transportation, urban construction and environmental protection.

Electronics is also one of the subjects with a wide range of applications and penetration. The application of electronics in industry has greatly improved the labour productivity 。 electronic technique And Mechanics Combined to produce various types of numerical control machine 、 manipulator and robot , a fully automated and flexible production line has emerged. The application of electronics in production inspection can effectively control product quality and indicate the improvement direction of product design and production. Electronics for oil field development It can improve the success rate of oil exploration and organize the exploitation scientifically. The application of electronics in the management of power production can realize the rational allocation of power and improve the safety of production. Electronics can be used for transportation to guide ships and aircraft to navigate safely.

The use of electronics in agriculture has also brought great benefits to agriculture. Meteorology is very important for agriculture. Using radio and radar methods, we can collect meteorological data in local areas. Special meteorological satellites can regularly broadcast large areas of the world cloud chart The communication network is used to transmit meteorological information, and the computer is used for meteorological information processing and forecasting. utilize Remote sensing data Information such as soil moisture, crop growth, diseases and pests can be obtained. Electronics can also be used for crop breeding, germination and grain drying.

The application of electronics in military affairs has improved the performance of various weapons and equipment, and profoundly affected the way of military behavior. In modern weapons and equipment, the proportion of electronic equipment is increasing. Electronic technology is also an indispensable means for intelligence reconnaissance, communication and liaison, analysis and decision-making, command and control, etc. Because of this, electronic warfare, an invisible war, has become an eye-catching form of war.

Electronics provides a powerful means for scientific research. Astronomers use giant radio telescope , expanding the observation range to the depths of the universe of 20 billion light years; For geographers remote sensing The method of sahara desert Immersed ancient rivers; biologist Using the method of information theory, it explains the secret of biological heredity - genetic code; Physicists found 2.7K Cosmic background radiation ； Chemists use Ultrahigh pressure electron microscope The observation resolution has reached the molecular level. Scientists from all walks of life Online Retrieval And the global communication network can quickly query the required information from the world's vast database.

The application of electronics in education has provided many new technologies for the modernization of education. Radio recorder , TV video recorder As a means of education, electronic language classrooms, program teaching machines, and television education satellites have emerged one after another. Due to the rapid renewal and increase of knowledge, the concept of lifelong education has been formed, and the proportion of open schools with electronic technology as the core in the entire education system will be higher and higher.^[8]

Electronics is used in medicine, and various types of electronic monitoring systems, physical therapy systems, auxiliary diagnostic systems, and even medical expert systems have emerged. X-ray tomography is one of the important scientific advances in the 1970s, and the main technology used is image processing Technology and high-speed high-capacity computers. The introduction of electronics into the family has reduced people's housework and made family life more colorful.

The human society is entering a new stage of development, which is characterized by the rapid expansion of information technological revolution It is on the rise. It is the latest achievements in electronics that promote this transformation microelectronics Technology. All kinds of information operations are completed with the help of electronic science and technology. The three "A" revolutions widely talked about today (i.e. factory automation Office Automation , home automation) and three "C" revolutions (i.e signal communication 、 computer 、 control ）Neither is it based on electronics. Because of this, many countries are developing electronics, especially Microelectronics , as one of its important national policies.

Book information

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electronics

Title: Electronics

Author: Horowitz

press: Electronic Industry Press

Published in: March 2009

ISBN : 9787121083587

Format: 16

Price: 108.00 yuan

content

Electronics Harvard University The classic textbook of, Self publishing It has been translated into many languages. Electronics emphasizes the practical methods required by the designers of electronic circuit systems, that is, a comprehensive summary of the basic principles of circuits, experience criteria and a large number of practical circuit design skills. It focuses on the design principles and applications of electronics and its circuits. It not only covers all the knowledge points that are usually studied in electronics, but also supplements a large number of new applications and design points in digital electronics. yes High frequency amplifier 、 radio frequency Communication modulation circuit design, low power consumption design, bandwidth compression, signal measurement and processing and other important circuit design, as well as the difficulties in electronic circuit manufacturing process design are also explained easily. Electronics contains a wealth of electronics circuit analysis Design examples and a large number of charts and data, comprehensive and thoroughly elaborated, is a world-wide recognized excellent textbook for electronic circuit analysis, design and application.

Electronics can be used as electrical 、 Electronics 、 signal communication 、 computer And automation Teaching materials or reference books of professional basic courses for undergraduate students majoring in. For engaging in Electronic Engineering , communication, microelectronics and other aspects of circuit design engineering and technical personnel, is also a good book with high reference value.

author

Horowitz ， Harvard College Physics Professor, teaching at Harvard Physics and Electronics , pioneered Harvard University Experimental electronics course. His research interests are extensive and he dabbles in observation Astrophysics 、 X-ray And particle Microscopy , light interference measuring technique And alien exploration. As has 60 articles Scientific papers With the author of the report, he not only works extensively as a consultant for industry and government departments, but also designs a large number of electronic and photographic equipment.