Radio

Article

Radio is the transmission and reception of information or energy using electromagnetic waves. A transmitter generates a radio-frequency signal, modulates it with information, and feeds it to an antenna, while a receiver detects and processes the transmitted wave.

Information may be carried by variations in amplitude, frequency, phase, pulse timing, or digitally encoded symbols. Radio systems can transmit speech, music, images, data, control commands, navigation signals, and measurements.

Propagation changes across the spectrum. Radio waves may travel by ground wave, reflect or refract in the ionosphere, pass through the atmosphere, follow line-of-sight paths, or be relayed by satellites and repeaters.

Applications include broadcasting, mobile phones, wireless networking, radar, remote control, satellite communication, emergency services, radio astronomy, and navigation. Reliable operation depends on antennas, modulation, bandwidth, power, coding, filtering, and spectrum management.

Source details and credits

• Source / publisher: Wikipedia
• URL type: WWW
• Credits: Wikipedia
• URL: https://en.wikipedia.org/wiki/Radio