Coverage (telecommunication)

From Wikipedia, the free encyclopedia

In telecommunications, the coverage is the geographic area that the station in question covers. Broadcasters and telecommunications companies frequently produce coverage maps to indicate to users the station's intended service area.

1 Rain fade
2 Coverage noticer
3 See also
4 External links

[edit] Rain fade

Rain fade refers to the absorption of a microwave Radio Frequency (RF) signal by rain or snow, and is especially prevalent in frequencies above 11 GHz. It also refers to the degradation of a signal caused by the electromagnetic interference of the leading edge of a storm front. Rain fade can be caused by rain or snow at the uplink or downlink location. It does not need to be raining at a location for it to be affected by rain fade. The signal may pass through rain or snow many miles away, especially if the satellite dish has a low look angle. From 5 to 20 percent of rain fade or satellite signal attenuation may also be caused by rain, snow or ice on the downlink antenna reflector, radome or feed horn.

Possible ways to overcome rain fade are site diversity, uplink power control, variable rate encoding, receiving antennas larger than the requested size for normal weather conditions, and super hydrophobic rain, snow and ice repellent coatings.

[edit] Coverage noticer

A coverage noticer is a device that beeps (or vibrates) when in a certain zone there is no coverage. This is fundamental for critical services (security, emergency and so on). When the user goes to a covered area, the noticer ceases in the beeping.

It can be integrated in a mobile phone also.