Electronic engineering is a sub-discipline of electrical engineering which emerged in the early 20th century and is distinguished by the additional use of active components such as semiconductor devices to amplify and control electric current flow. Previously electrical engineering only used passive devices such as mechanical switches, resistors, inductors, and capacitors.
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) 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.
History and development
Electronics engineering as a profession emerged following the identification of the electron in 1897 and 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 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 the subsequent peace-time consumer revolution.
Specialist areas
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 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 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 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 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 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.