audio-frequency electromagnetic method
61Antenna (radio) — Whip antenna on car …
62Metamaterial — Negative index metamaterial array configuration, which was constructed of copper split ring resonators and wires mounted on interlocking sheets of fiberglass circuit board. The total array consists of 3 by 20×20 unit cells with overall dimensions …
63Optical fiber — A bundle of optical fibers A TOSLINK fiber optic audio c …
64Doppler effect — Change of wavelength caused by motion of the source. An animation illustrating how the Doppler effect causes a car engine or siren to soun …
65Superlens — A superlens, super lens or perfect lens is a lens which uses metamaterials to go beyond the diffraction limit. The diffraction limit is an inherent limitation in conventional optical devices or lenses.[1] In 2000, a type of lens was proposed,… …
66telecommunications media — Introduction equipment and systems metal wire, terrestrial and satellite radio, and optical fibre employed in the transmission of electromagnetic signals. Transmission media and the problem of signal degradation Every… …
67Multipath propagation — This article is about the electromagnetic propagation phenomenon. For the computing storage term, see Multipath I/O. For the routing term, see Multipath Routing. In wireless telecommunications, multipath is the propagation phenomenon that results …
68Quantum mechanics — For a generally accessible and less technical introduction to the topic, see Introduction to quantum mechanics. Quantum mechanics …
69Impedance matching — In electronics, impedance matching is the practice of designing the input impedance of an electrical load (or the output impedance of its corresponding signal source) to maximize the power transfer and/or minimize reflections from the load.… …
70Pickup (music) — A pickup device acts as a transducer that captures mechanical vibrations (usually from suitably equipped stringed instruments such as the electric guitar, electric bass guitar or electric violin) and converts them to an electrical signal, which… …
