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Explain the +2 class physics topic sky wave propagation

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Skywave

For the satellite terminal company in Ottawa, see SkyWave Mobile Communications.



Radio waves (black) reflecting off the ionosphere (red) during skywave propagation

In radio communication, skywave or skiprefers to the propagation of radio wavesreflected or refracted back toward Earth from the ionosphere, an electrically charged layer of the upper atmosphere. Since it is not limited by the curvature of the Earth, skywave propagation can be used to communicate beyond the horizon, at intercontinental distances. It is mostly used in the shortwavefrequency bands.

As a result of skywave propagation, a signal from a distant AM broadcasting station, a shortwave station, or – during sporadic E propagation conditions (principally during the summer months in both hemispheres) a distant VHF FM or TV station – can sometimes be received as clearly as local stations. Most long-distance shortwave (high frequency) radio communication – between 3 and 30 MHz – is a result of skywave propagation. Since the early 1920s amateur radio operators (or "hams"), limited to lower transmitter power than broadcast stations, have taken advantage of skywave for long distance (or "DX") communication.

Skywave propagation is distinct from:

groundwave propagation, where radio waves travel near Earth's surface without being reflected or refracted by the atmosphere – the dominant propagation mode at lower frequencies,

line-of-sight propagation, in which radio waves travel in a straight line, the dominant mode at higher frequencies.

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Last edited 1 month ago by Citation bot

RELATED ARTICLES

Shortwave radio

radio frequencies in the range of 1.6-30 megahertz (ITU region 1) or 1.7-30 megahertz (ITU region 2)

High frequency

frequencies between 3-30MHz

Radio propagation

behavior of radio waves as they travel, or are propagated, from one point to another, or into various parts of the atmosphere



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