Communication channelA communication channel refers either to a physical transmission medium such as a wire, or to a logical connection over a multiplexed medium such as a radio channel in telecommunications and computer networking. A channel is used for information transfer of, for example, a digital bit stream, from one or several senders to one or several receivers.
Cable televisionCable television is a system for delivering broadcast programming to viewers by radio frequency (RF) signals transmitted through coaxial cable and through fibre-optic cable.
Carrier telephonyAnalog multiplexing technique used in early telephone systemsEarly telephony circuits for long-distance calls. Solid lines shows extent in 1929, dotted lines show estimate for 1934.Carrier telephony is a method for carrying several simultaneous long-distance telephone conversations over the same transmission line. Each conversation is shifted to a different frequency band, allowing the channels to share the line by frequency-division multiplexing (FDM).
Bandwidth (signal processing)Bandwidth is the difference between the upper and lower frequencies in a continuous band of frequencies. It is typically measured in unit of hertz (symbol Hz). It may refer more specifically to two subcategories: Passband bandwidth is the difference between the upper and lower cutoff frequencies of, for example, a band-pass filter, a communication channel, or a signal spectrum.
RadioRadio is the technology of communicating using radio waves. Radio waves are electromagnetic waves of frequency between 3 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmitter connected to an antenna which radiates the waves. They can be received by other antennas connected to a radio receiver; this is the fundamental principle of radio communication.
Television broadcasterTelecommunications network for TV programming A BBC television and radio transmitting station, Crystal Palace, with Croydon transmitting station in the distance A television broadcaster or television network is a telecommunications network for the distribution of television content, where a central operation provides programming to many television stations, pay television providers or, in the United States, multichannel video programming distributors.
TelecommunicationsTransmission of information electromagneticallyEarth station at the satellite communication facility Raisting Earth Station in Raisting, Weilheim-Schongau, Bavaria, GermanyTelecommunication, often used in its plural form or abbreviated as telecom, is the transmission of information over a distance using electrical or electronic means, typically through cables, radio waves, or other communication technologies.
Communications satelliteArtificial satellite that relays radio signals An Iridium satellite for satellite telephony Part of a series onSpaceflight History History of spaceflight Space Race Timeline of spaceflight Space probes Lunar missions Mars missions Applications Communications Earth observation Exploration Espionage Military Navigation Colonization Habitation Exploration Telescopes Tourism Spacecraft Robotic spacecraft Satellite Space probe Cargo spacecraft Crewed spacecraft Apollo Lunar Module Space capsules Space Shuttle Space stations Spaceplanes Vostok Space launch Spaceport Launch pad Expendable and reusable launch vehicles Escape velocity Non-rocket spacelaunch Spaceflight types Sub-orbital Orbital Interplanetary Interstellar Intergalactic List of space organizations Space agencies Space forces Companies Spaceflight portalvte A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a transponder; it creates a communication channel between a source transmitter and a receiver at different locations on Earth.Parallel communicationIn data transmission, parallel communication is a method of conveying multiple binary digits (bits) simultaneously using multiple conductors. This contrasts with serial communication, which conveys only a single bit at a time; this distinction is one way of characterizing a communications link. The basic difference between a parallel and a serial communication channel is the number of electrical conductors used at the physical layer to convey bits.TrunkingIn telecommunications, trunking is a technology for providing network access to multiple clients simultaneously by sharing a set of circuits, carriers, channels, or frequencies, instead of providing individual circuits or channels for each client. This is reminiscent to the structure of a tree with one trunk and many branches.
Optical fiberAn optical fiber, or optical fibre, is a flexible glass or plastic fiber that can transmit light from one end to the other. Such fibers are widely used in fiber-optic communication, where they permit transmission over longer distances and at higher bandwidths (data transfer rates) than electrical cables. Fibers are used instead of cables because signals travel along them with less loss and are immune to electromagnetic interference.
Spectral bandSpectral bands are regions of a given spectrum, having a specific range of wavelengths or frequencies. Most often, it refers to electromagnetic bands, regions of the electromagnetic spectrum. More generally, spectral bands may also be defined in the spectra of other types of signals, e.g., noise spectrum. A frequency band is an interval in the frequency domain, limited by a lower frequency and an upper frequency.*As an Amazon Associate I earn from qualifying purchases.