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65-496: It covers fields such as analog electronics , digital electronics , consumer electronics , embedded systems and power electronics . It is also involved in many related fields, for example solid-state physics , radio engineering , telecommunications , control systems , signal processing , systems engineering , computer engineering , instrumentation engineering , electric power control , photonics and robotics . The Institute of Electrical and Electronics Engineers (IEEE)

130-460: A broadcast transmitter , a transmitter used in broadcasting , as in FM radio transmitter or television transmitter . This usage typically includes both the transmitter proper, the antenna, and often the building it is housed in. A transmitter can be a separate piece of electronic equipment, or an electrical circuit within another electronic device. A transmitter and a receiver combined in one unit

195-467: A continuously variable signal, in contrast to digital electronics where signals usually take only two levels . The term analogue describes the proportional relationship between a signal and a voltage or current that represents the signal. The word analogue is derived from the Greek word ανάλογος analogos meaning proportional . An analogue signal uses some attribute of the medium to convey

260-472: A frequency modulation (FM) transmitter, it is added by varying the radio signal's frequency slightly. Many other types of modulation are also used. The radio signal from the transmitter is applied to the antenna , which radiates the energy as radio waves. The antenna may be enclosed inside the case or attached to the outside of the transmitter, as in portable devices such as cell phones, walkie-talkies, and garage door openers . In more powerful transmitters,

325-499: A postgraduate degree such as a Master of Science , Doctor of Philosophy in Engineering, or an Engineering Doctorate . The master's degree is being introduced in some European and American Universities as a first degree and the differentiation of an engineer with graduate and postgraduate studies is often difficult. In these cases, experience is taken into account. The master's degree may consist of either research, coursework or

390-544: A radio frequency alternating current , which is applied to the antenna . When excited by this alternating current, the antenna radiates radio waves. Transmitters are necessary component parts of all electronic devices that communicate by radio , such as radio (audio) and television broadcasting stations, cell phones , walkie-talkies , wireless computer networks , Bluetooth enabled devices, garage door openers , two-way radios in aircraft, ships, spacecraft, radar sets and navigational beacons. The term transmitter

455-429: A radio frequency signal which when applied to the antenna produces the radio waves, called the carrier signal . It combines the carrier with the modulation signal, a process called modulation . The information can be added to the carrier in several different ways, in different types of transmitters. In an amplitude modulation (AM) transmitter, the information is added to the radio signal by varying its amplitude . In

520-464: A transducer which converts one type of energy into another (e.g. a microphone ). The signals take any value from a given range, and each unique signal value represents different information. Any change in the signal is meaningful, and each level of the signal represents a different level of the phenomenon that it represents. For example, suppose the signal is being used to represent temperature, with one volt representing one degree Celsius . In such

585-654: A certified degree program, the engineer must satisfy a range of requirements, including work experience requirements, before being certified. Once certified the engineer is designated the title of Professional Engineer (in the United States, Canada, and South Africa), Chartered Engineer or Incorporated Engineer (in the United Kingdom, Ireland, India, and Zimbabwe), Chartered Professional Engineer (in Australia and New Zealand) or European Engineer (in much of

650-505: A furnace's temperature remains constant. For this reason, instrumentation engineering is often viewed as the counterpart of control engineering. Computer engineering deals with the design of computers and computer systems. This may involve the design of new computer hardware , the design of PDAs or the use of computers to control an industrial plant . Development of embedded systems —systems made for specific tasks (e.g., mobile phones)—is also included in this field. This field includes

715-548: A good understanding of electronics engineering and physics ; for example, radar guns use the Doppler effect to measure the speed of oncoming vehicles. Similarly, thermocouples use the Peltier–Seebeck effect to measure the temperature difference between two points. Often instrumentation is not used by itself, but instead as the sensors of larger electrical systems. For example, a thermocouple might be used to help ensure

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780-518: A high voltage spark between two conductors. Beginning in 1895, Guglielmo Marconi developed the first practical radio communication systems using these transmitters, and radio began to be used commercially around 1900. Spark transmitters could not transmit audio (sound) and instead transmitted information by radiotelegraphy : the operator tapped on a telegraph key which turned the transmitter on-and-off to produce radio wave pulses spelling out text messages in telegraphic code, usually Morse code . At

845-440: A major in electronics engineering. The length of study for such a degree is usually three or four years and the completed degree may be designated as a Bachelor of Engineering , Bachelor of Science , Bachelor of Applied Science , or Bachelor of Technology depending upon the university. Many UK universities also offer Master of Engineering ( MEng ) degrees at the graduate level. Some electronics engineers also choose to pursue

910-429: A mixture of the two. The Doctor of Philosophy consists of a significant research component and is often viewed as the entry point to academia. In most countries, a bachelor's degree in engineering represents the first step towards certification and the degree program itself is certified by a professional body. Certification allows engineers to legally sign off on plans for projects affecting public safety. After completing

975-437: A non-mechanical device. The growth of electronics was rapid. By the early 1920s, commercial radio broadcasting and communications were becoming widespread and electronic amplifiers were being used in such diverse applications as long-distance telephony and the music recording industry. The discipline was further enhanced by the large amount of electronic systems development during World War II in such as radar and sonar , and

1040-413: A radio wave. A radio transmitter is an electronic circuit which transforms electric power from a power source, a battery or mains power, into a radio frequency alternating current to apply to the antenna, and the antenna radiates the energy from this current as radio waves. The transmitter also encodes information such as an audio or video signal into the radio frequency current to be carried by

1105-404: A signal is, mainly the noise present in the original signal and the noise added by processing (see signal-to-noise ratio ). Fundamental physical limits such as the shot noise in components limits the resolution of analogue signals. In digital electronics additional precision is obtained by using additional digits to represent the signal. The practical limit in the number of digits is determined by

1170-407: A system are determined, telecommunication engineers design the transmitters and receivers needed for such systems. These two are sometimes combined to form a two-way communication device known as a transceiver . A key consideration in the design of transmitters is their power consumption as this is closely related to their signal strength . If the signal strength of a transmitter is insufficient

1235-463: A system, 10 volts would represent 10 degrees, and 10.1 volts would represent 10.1 degrees. Another method of conveying an analogue signal is to use modulation . In this, some base carrier signal has one of its properties altered: amplitude modulation (AM) involves altering the amplitude of a sinusoidal voltage waveform by the source information, frequency modulation (FM) changes the frequency. Other techniques, such as phase modulation or changing

1300-586: A variety of license classes depending on use such as broadcast , marine radio , Airband , Amateur and are restricted to certain frequencies and power levels. A body called the International Telecommunication Union (ITU) allocates the frequency bands in the radio spectrum to various classes of users. In some classes, each transmitter is given a unique call sign consisting of a string of letters and numbers which must be used as an identifier in transmissions. The operator of

1365-480: A wide range of electronic applications from the flight and propulsion systems of commercial airplanes to the cruise control present in many modern cars . It also plays an important role in industrial automation . Control engineers often use feedback when designing control systems . Instrumentation engineering deals with the design of devices to measure physical quantities such as pressure , flow , and temperature .The design of such instrumentation requires

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1430-421: Is distributed-element circuits , built from pieces of transmission line . Transmitter In electronics and telecommunications , a radio transmitter or just transmitter (often abbreviated as XMTR or TX in technical documents) is an electronic device which produces radio waves with an antenna with the purpose of signal transmission up to a radio receiver . The transmitter itself generates

1495-677: Is a recognised professional designation in the United States. For most engineers not involved at the cutting edge of system design and development, technical work accounts for only a fraction of the work they do. A lot of time is also spent on tasks such as discussing proposals with clients, preparing budgets and determining project schedules. Many senior engineers manage a team of technicians or other engineers and for this reason, project management skills are important. Most engineering projects involve some form of documentation and strong written communication skills are therefore very important. The workplaces of electronics engineers are just as varied as

1560-441: Is a serious concern for electronics engineers. Membership and participation in technical societies, regular reviews of periodicals in the field, and a habit of continued learning are therefore essential to maintaining proficiency, which is even more crucial in the field of consumer electronics products. Analog electronics Analogue electronics ( American English : analog electronics ) are electronic systems with

1625-425: Is called a transceiver . The purpose of most transmitters is radio communication of information over a distance. The information is provided to the transmitter in the form of an electronic signal called the modulation signal, such as an audio (sound) signal from a microphone, a video (TV) signal from a video camera, or in wireless networking devices, a digital signal from a computer. The transmitter generates

1690-567: Is one of the most important professional bodies for electronics engineers in the US; the equivalent body in the UK is the Institution of Engineering and Technology (IET). The International Electrotechnical Commission (IEC) publishes electrical standards including those for electronics engineering. Electronics engineering as a profession emerged following the identification of the electron in 1897 and

1755-608: Is random disturbances or variations, some caused by the random thermal vibrations of atomic particles. Since all variations of an analogue signal are significant, any disturbance is equivalent to a change in the original signal and so appears as noise. As the signal is copied and re-copied, or transmitted over long distances, these random variations become more significant and lead to signal degradation . Other sources of noise may include crosstalk from other signals or poorly designed components. These disturbances are reduced by shielding and by using low-noise amplifiers (LNA). Since

1820-418: Is used to change a digital signal to an analogue signal. A DAC takes a series of binary numbers and converts it to an analogue signal. It is common to find a DAC in the gain-control system of an op-amp which in turn may be used to control digital amplifiers and filters. Analogue circuits are typically harder to design, requiring more skill than comparable digital systems to conceptualize. An analogue circuit

1885-436: Is usually designed by hand because the application is built into the hardware. Digital hardware, on the other hand, has a great deal of commonality across applications and can be mass-produced in a standardised form. Hardware design consists largely of repeated identical blocks and the design process can be highly automated. This is one of the main reasons that digital systems have become more common than analogue devices. However,

1950-411: Is usually limited to equipment that generates radio waves for communication purposes; or radiolocation , such as radar and navigational transmitters. Generators of radio waves for heating or industrial purposes, such as microwave ovens or diathermy equipment, are not usually called transmitters, even though they often have similar circuits. The term is popularly used more specifically to refer to

2015-640: The UHF and microwave ranges, using new active devices such as the magnetron , klystron , and traveling wave tube . The invention of the transistor allowed the development in the 1960s of small portable transmitters such as wireless microphones , garage door openers and walkie-talkies . The development of the integrated circuit (IC) in the 1970s made possible the current proliferation of wireless devices , such as cell phones and Wi-Fi networks, in which integrated digital transmitters and receivers ( wireless modems ) in portable devices operate automatically, in

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2080-539: The microcontroller and its applications. Computer engineers may also work on a system's software . However, the design of complex software systems is often the domain of software engineering which falls under computer science , which is usually considered a separate discipline. VLSI design engineering VLSI stands for very large-scale integration . It deals with fabrication of ICs and various electronic components. In designing an integrated circuit, electronics engineers first construct circuit schematics that specify

2145-400: The transmission of information across a medium such as a co-axial cable , an optical fiber , or free space . Transmissions across free space require information to be encoded in a carrier wave in order to be transmitted, this is known as modulation . Popular analog modulation techniques include amplitude modulation and frequency modulation . Once the transmission characteristics of

2210-685: The 1920s. All these early technologies were replaced by vacuum tube transmitters in the 1920s, which used the feedback oscillator invented by Edwin Armstrong and Alexander Meissner around 1912, based on the Audion ( triode ) vacuum tube invented by Lee De Forest in 1906. Vacuum tube transmitters were inexpensive and produced continuous waves , and could be easily modulated to transmit audio (sound) using amplitude modulation (AM). This made AM radio broadcasting possible, which began in about 1920. Practical frequency modulation (FM) transmission

2275-472: The European Union). A degree in electronics generally includes units covering physics , chemistry , mathematics , project management and specific topics in electrical engineering . Initially, such topics cover most, if not all, of the subfields of electronics engineering. Students then choose to specialize in one or more subfields towards the end of the degree. Fundamental to the discipline are

2340-543: The UK's Institution of Engineering and Technology (IET). Members of the Institution of Engineering and Technology (MIET) are recognized professionally in Europe, as electrical and computer engineers. The IEEE claims to produce 30 percent of the world's literature in electrical and electronics engineering, has over 430,000 members, and holds more than 450 IEEE sponsored or cosponsored conferences worldwide each year. SMIEEE

2405-515: The US, these fall under Part 15 of the Federal Communications Commission (FCC) regulations. Although they can be operated without a license, these devices still generally must be type-approved before sale. The first primitive radio transmitters (called spark gap transmitters ) were built by German physicist Heinrich Hertz in 1887 during his pioneering investigations of radio waves. These generated radio waves by

2470-610: The antenna may be located on top of a building or on a separate tower, and connected to the transmitter by a feed line , that is a transmission line . Electromagnetic waves are radiated by electric charges when they are accelerated . Radio waves , electromagnetic waves of radio frequency , are generated by time-varying electric currents , consisting of electrons flowing through a metal conductor called an antenna which are changing their velocity and thus accelerating. An alternating current flowing back and forth in an antenna will create an oscillating magnetic field around

2535-505: The application of digital hardware is a function of the software / firmware and creating this is still largely a labour-intensive process. Since the early 2000s, there were some platforms that were developed which enabled analogue design to be defined using software - which allows faster prototyping. Furthermore, if a digital electronic device is to interact with the real world, it will always need an analogue interface. For example, every digital radio receiver has an analogue preamplifier as

2600-461: The background, to exchange data with wireless networks . The need to conserve bandwidth in the increasingly congested radio spectrum is driving the development of new types of transmitters such as spread spectrum , trunked radio systems and cognitive radio . A related trend has been an ongoing transition from analog to digital radio transmission methods. Digital modulation can have greater spectral efficiency than analog modulation ; that

2665-419: The conductor. The alternating voltage will also charge the ends of the conductor alternately positive and negative, creating an oscillating electric field around the conductor. If the frequency of the oscillations is high enough, in the radio frequency range above about 20 kHz, the oscillating coupled electric and magnetic fields will radiate away from the antenna into space as an electromagnetic wave,

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2730-411: The electrical components and describe the interconnections between them. When completed, VLSI engineers convert the schematics into actual layouts, which map the layers of various conductor and semiconductor materials needed to construct the circuit. Electronics is a subfield within the wider electrical engineering academic subject. Electronics engineers typically possess an academic degree with

2795-5642: The extensive engineering mathematics curriculum that is a prerequisite to a degree. The huge breadth of electronics engineering has led to the use of a large number of specialists supporting knowledge areas. Elements of vector calculus : divergence and curl ; Gauss' and Stokes' theorems , Maxwell's equations : differential and integral forms. Wave equation , Poynting vector . Plane waves : propagation through various media; reflection and refraction ; phase and group velocity ; skin depth . Transmission lines : characteristic impedance ; impedance transformation; Smith chart ; impedance matching ; pulse excitation. Waveguides : modes in rectangular waveguides; boundary conditions ; cut-off frequencies ; dispersion relations . Antennas: Dipole antennas ; antenna arrays ; radiation pattern; reciprocity theorem, antenna gain . Network graphs: matrices associated with graphs; incidence, fundamental cut set, and fundamental circuit matrices. Solution methods: nodal and mesh analysis. Network theorems: superposition, Thevenin and Norton's maximum power transfer, Wye-Delta transformation. Steady state sinusoidal analysis using phasors. Linear constant coefficient differential equations; time domain analysis of simple RLC circuits, Solution of network equations using Laplace transform : frequency domain analysis of RLC circuits. 2-port network parameters: driving point and transfer functions. State equations for networks. Electronic devices : Energy bands in silicon, intrinsic and extrinsic silicon. Carrier transport in silicon: diffusion current, drift current, mobility, resistivity. Generation and recombination of carriers. p-n junction diode, Zener diode , tunnel diode , BJT , JFET , MOS capacitor , MOSFET , LED , p-i-n and avalanche photo diode , LASERs. Device technology: integrated circuit fabrication process, oxidation, diffusion, ion implantation , photolithography, n-tub, p-tub and twin-tub CMOS process. Analog circuits : Equivalent circuits (large and small-signal) of diodes, BJT, JFETs, and MOSFETs. Simple diode circuits, clipping, clamping, rectifier. Biasing and bias stability of transistor and FET amplifiers. Amplifiers: single-and multi-stage, differential, operational, feedback and power. Analysis of amplifiers; frequency response of amplifiers. Simple op-amp circuits. Filters. Sinusoidal oscillators; criterion for oscillation; single-transistor and op-amp configurations. Function generators and wave-shaping circuits, Power supplies. Digital circuits : Boolean functions ( NOT , AND , OR , XOR ,...). Logic gates digital IC families ( DTL , TTL , ECL , MOS , CMOS ). Combinational circuits: arithmetic circuits, code converters, multiplexers , and decoders . Sequential circuits : latches and flip-flops, counters, and shift-registers. Sample and hold circuits, ADCs , DACs . Semiconductor memories . Microprocessor 8086 : architecture, programming, memory, and I/O interfacing. Signals and systems: Definitions and properties of Laplace transform , continuous-time and discrete-time Fourier series , continuous-time and discrete-time Fourier Transform , z-transform . Sampling theorems . Linear Time-Invariant (LTI) Systems : definitions and properties; causality, stability, impulse response, convolution, poles and zeros frequency response, group delay and phase delay . Signal transmission through LTI systems. Random signals and noise: probability , random variables , probability density function , autocorrelation , power spectral density , and function analogy between vectors & functions. Basic control system components; block diagrammatic description, reduction of block diagrams — Mason's rule . Open loop and closed loop (negative unity feedback) systems and stability analysis of these systems. Signal flow graphs and their use in determining transfer functions of systems; transient and steady-state analysis of LTI control systems and frequency response. Analysis of steady-state disturbance rejection and noise sensitivity. Tools and techniques for LTI control system analysis and design: root loci, Routh–Hurwitz stability criterion , Bode and Nyquist plots . Control system compensators: elements of lead and lag compensation, elements of proportional–integral–derivative (PID) control. Discretization of continuous-time systems using zero-order hold and ADCs for digital controller implementation. Limitations of digital controllers: aliasing. State variable representation and solution of state equation of LTI control systems. Linearization of Nonlinear dynamical systems with state-space realizations in both frequency and time domains. Fundamental concepts of controllability and observability for MIMO LTI systems. State space realizations: observable and controllable canonical form. Ackermann's formula for state-feedback pole placement. Design of full order and reduced order estimators. Analog communication systems: amplitude and angle modulation and demodulation systems, spectral analysis of these operations, superheterodyne noise conditions. Digital communication systems: pulse-code modulation (PCM), differential pulse-code modulation (DPCM), delta modulation (DM), digital modulation – amplitude, phase- and frequency-shift keying schemes ( ASK , PSK , FSK ), matched-filter receivers, bandwidth consideration and probability of error calculations for these schemes, GSM , TDMA . Professional bodies of note for electrical engineers USA's Institute of Electrical and Electronics Engineers (IEEE) and

2860-601: The first stage in the receive chain. Design of analogue circuits has been greatly eased by the advent of software circuit simulators such as SPICE . IBM developed their own in-house simulator, ASTAP , in the 1970s which used an unusual (compared to other simulators) sparse matrix method of circuit analysis. Analogue circuits can be entirely passive , consisting of resistors , capacitors and inductors . Active circuits also contain active elements such as transistors . Traditional circuits are built from lumped elements – that is, discrete components. However, an alternative

2925-468: The information is quantized , as long as the signal stays inside a range of values, it represents the same information. In digital circuits the signal is regenerated at each logic gate , lessening or removing noise. In analogue circuits, signal loss can be regenerated with amplifiers . However, noise is cumulative throughout the system and the amplifier itself will add to the noise according to its noise figure . A number of factors affect how precise

2990-418: The information is encoded differently in analogue and digital electronics , the way they process a signal is consequently different. All operations that can be performed on an analogue signal such as amplification , filtering , limiting, and others, can also be duplicated in the digital domain. Every digital circuit is also an analogue circuit, in that the behaviour of any digital circuit can be explained using

3055-519: The information, or digital , in which case the signal varies according to a series of discrete values representing the information. For analog signals, signal processing may involve the amplification and filtering of audio signals for audio equipment and the modulation and demodulation of radio frequency signals for telecommunications . For digital signals, signal processing may involve compression , error checking and error detection , and correction. Telecommunications engineering deals with

3120-431: The other hand, are not affected at all by the presence of noise until a certain threshold is reached, at which point they fail catastrophically. For digital telecommunications , it is possible to increase the noise threshold with the use of error detection and correction coding schemes and algorithms. Nevertheless, there is still a point at which catastrophic failure of the link occurs. In digital electronics, because

3185-421: The output frequency. Older designs used an oscillator at a lower frequency, which was multiplied by frequency multipliers to get a signal at the desired frequency. Modern designs more commonly use an oscillator at the operating frequency which is stabilized by phase locking to a very stable lower frequency reference, usually a crystal oscillator. Two radio transmitters in the same area that attempt to transmit on

3250-437: The performance of the analogue-to-digital converter (ADC), since digital operations can usually be performed without loss of precision. The ADC takes an analogue signal and changes it into a series of binary numbers . The ADC may be used in simple digital display devices, e. g., thermometers or light meters but it may also be used in digital sound recording and in data acquisition. However, a digital-to-analogue converter (DAC)

3315-534: The phase of the carrier signal, are also used. In an analogue sound recording, the variation in pressure of a sound striking a microphone creates a corresponding variation in the current passing through it or voltage across it. An increase in the volume of the sound causes the fluctuation of the current or voltage to increase proportionally while keeping the same waveform or shape. Mechanical , pneumatic , hydraulic , and other systems may also use analogue signals. Analogue systems invariably include noise that

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3380-400: The radio waves. When they strike the antenna of a radio receiver , the waves excite similar (but less powerful) radio frequency currents in it. The radio receiver extracts the information from the received waves. A practical radio transmitter mainly consists of the following parts: In higher frequency transmitters, in the UHF and microwave range, free running oscillators are unstable at

3445-486: The receiver, these pulses were sometimes directly recorded on paper tapes, but more common was audible reception. The pulses were audible as beeps in the receiver's earphones, which were translated back to text by an operator who knew Morse code. These spark-gap transmitters were used during the first three decades of radio (1887–1917), called the wireless telegraphy or "spark" era. Because they generated damped waves , spark transmitters were electrically "noisy". Their energy

3510-485: The rules of analogue circuits. The use of microelectronics has made digital devices cheap and widely available. The effect of noise on an analogue circuit is a function of the level of noise. The greater the noise level, the more the analogue signal is disturbed, slowly becoming less usable. Because of this, analogue signals are said to "fail gracefully". Analogue signals can still contain intelligible information with very high levels of noise. Digital circuits, on

3575-475: The same frequency will interfere with each other, causing garbled reception, so neither transmission may be received clearly. Interference with radio transmissions can not only have a large economic cost, it can be life-threatening (for example, in the case of interference with emergency communications or air traffic control ). For this reason, in most countries, use of transmitters is strictly controlled by law. Transmitters must be licensed by governments, under

3640-454: The sciences of physics and mathematics as these help to obtain both a qualitative and quantitative description of how such systems will work. Today, most engineering work involves the use of computers and it is commonplace to use computer-aided design and simulation software programs when designing electronic systems. Although most electronic engineers will understand basic circuit theory, the theories employed by engineers generally depend upon

3705-512: The signal's information will be corrupted by noise . Aviation - electronics engineering and Aviation-telecommunications engineering , are concerned with aerospace applications. Aviation- telecommunication engineers include specialists who work on airborne avionics in the aircraft or ground equipment. Specialists in this field mainly need knowledge of computer , networking , IT , and sensors . These courses are offered at such as Civil Aviation Technology Colleges . Control engineering has

3770-485: The signal's information. For example, an aneroid barometer uses the angular position of a needle on top of a contracting and expanding box as the signal to convey the information of changes in atmospheric pressure . Electrical signals may represent information by changing their voltage , current , frequency , or total charge . Information is converted from some other physical form (such as sound , light , temperature , pressure , position) to an electrical signal by

3835-403: The subsequent invention of the vacuum tube which could amplify and rectify small electrical signals, that inaugurated the field of electronics. Practical applications started with the invention of the diode by Ambrose Fleming and the triode by Lee De Forest in the early 1900s, which made the detection of small electrical voltages such as radio signals from a radio antenna possible with

3900-419: The subsequent peace-time consumer revolution following the invention of transistor by William Shockley , John Bardeen and Walter Brattain . Electronics engineering has many subfields. This section describes some of the most popular. Electronic signal processing deals with the analysis and manipulation of signals . Signals can be either analog , in which case the signal varies continuously according to

3965-512: The transmitter usually must hold a government license, such as a general radiotelephone operator license , which is obtained by passing a test demonstrating adequate technical and legal knowledge of safe radio operation. Exceptions to the above regulations allow the unlicensed use of low-power short-range transmitters in consumer products such as cell phones , cordless telephones , wireless microphones , walkie-talkies , Wi-Fi and Bluetooth devices, garage door openers , and baby monitors . In

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4030-400: The types of work they do. Electronics engineers may be found in the pristine laboratory environment of a fabrication plant, the offices of a consulting firm or in a research laboratory. During their working life, electronics engineers may find themselves supervising a wide range of individuals including scientists, electricians, programmers, and other engineers. Obsolescence of technical skills

4095-473: The work they do. For example, quantum mechanics and solid-state physics might be relevant to an engineer working on VLSI but are largely irrelevant to engineers working with embedded systems . Apart from electromagnetics and network theory, other items in the syllabus are particular to electronic engineering courses. Electrical engineering courses have other specialisms such as machines , power generation , and distribution . This list does not include

4160-440: Was invented by Edwin Armstrong in 1933, who showed that it was less vulnerable to noise and static than AM. The first FM radio station was licensed in 1937. Experimental television transmission had been conducted by radio stations since the late 1920s, but practical television broadcasting didn't begin until the late 1930s. The development of radar during World War II motivated the evolution of high frequency transmitters in

4225-498: Was spread over a broad band of frequencies , creating radio noise which interfered with other transmitters. Damped wave emissions were banned by international law in 1934. Two short-lived competing transmitter technologies came into use after the turn of the century, which were the first continuous wave transmitters: the arc converter ( Poulsen arc ) in 1904 and the Alexanderson alternator around 1910, which were used into

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