Troposcatter
Troposfærisk sammenlignet med line-of-sight radiokommunikation.
Troposcatter er en langvejs kommunikationsforbindelse på op til 300 km. Denne radioudbredelsesmetode anvender troposfærisk spredningsfænomenet, hvor radiobølger ved specifikke frekvenser spredes tilfældigt når de passerer gennem de øvre lag af troposfæren. Radiosignaler transmitteres i tæt stråle rettet mod tropopausen, midtvejs mellem sender og modtager stederne; så signalerne her passerer gennem troposfæren, hvor de spredes og kan så modtages af modtagerstationen. [1]
Troposcatter anvender frekvenser på omkring 2 GHz.
Troposacatter forbindelserne er nu sjældne. Nu benyttes satellitforbindelser.
ACE High var et NATO Troposcatter system. Det gik fra Norge via Torphøj ved Give til Tyskland.
Kilder/referencer
- ^ "FS-1037C Definition of tropospheric scatter". Arkiveret fra originalen 20. marts 2016. Hentet 1. maj 2012.
Eksterne henvisninger
- Russian tropospheric relay communication network
- Troposcatter communication network maps
- Jane's AN/TRC-170(v)
- Tropospheric Scatter Communications Systems Air Power Australia
|
Medier brugt på denne side
Tropospheric scatter.jpg
Original description: Tropospheric scatter and Line of Sight Communications
Original description: Tropospheric scatter and Line of Sight Communications
White Alice Site, Tropospheric Antennas HAER AK-21-A-2.jpg
Parabolic antenna used in the White Alice Communication System built around 1958 in Alaska by Western Electric and the US Air Force, which provided telephone communication between isolated communities. It was a tropospheric scatter system; large antennas like this beamed 50 kW signals at about 900 MHz at a low angle into the horizon, where they scattered off the tropopause, with a tiny fraction returning to Earth beyond the horizon. Looking East. The tower at right supports the feed horn for the antenna. The system became obsolete with the advent of communications satellites in the 1960s.
Parabolic antenna used in the White Alice Communication System built around 1958 in Alaska by Western Electric and the US Air Force, which provided telephone communication between isolated communities. It was a tropospheric scatter system; large antennas like this beamed 50 kW signals at about 900 MHz at a low angle into the horizon, where they scattered off the tropopause, with a tiny fraction returning to Earth beyond the horizon. Looking East. The tower at right supports the feed horn for the antenna. The system became obsolete with the advent of communications satellites in the 1960s.