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  2. Microwave transmission - Wikipedia

    en.wikipedia.org/wiki/Microwave_transmission

    Microwave signals are normally limited to the line of sight, so long-distance transmission using these signals requires a series of repeaters forming a microwave relay network. It is possible to use microwave signals in over-the-horizon communications using tropospheric scatter , but such systems are expensive and generally used only in ...

  3. Tropospheric scatter - Wikipedia

    en.wikipedia.org/wiki/Tropospheric_scatter

    Normally, signals in the microwave frequency range travel in straight lines, and so are limited to line-of-sight applications, in which the receiver can be 'seen' by the transmitter. Communication distances are limited by the visual horizon to around 48–64 kilometres (30–40 mi). Troposcatter allows microwave communication beyond the horizon.

  4. Over-the-horizon radar - Wikipedia

    en.wikipedia.org/wiki/Over-the-horizon_radar

    MADRE over-the-horizon radar at the NRL's Chesapeake Bay Detachment U.S. Navy Relocatable Over-the-Horizon Radar station. The most common type of OTH radar, OTH-B (backscatter), [3] uses skywave or "skip" propagation, in which shortwave radio waves are refracted off an ionized layer in the atmosphere, the ionosphere, and return to Earth some distance away.

  5. Microwave - Wikipedia

    en.wikipedia.org/wiki/Microwave

    Wireless LAN protocols, such as Bluetooth and the IEEE 802.11 specifications used for Wi-Fi, also use microwaves in the 2.4 GHz ISM band, although 802.11a uses ISM band and U-NII frequencies in the 5 GHz range. Licensed long-range (up to about 25 km) Wireless Internet Access services have been used for almost a decade in many countries in the 3 ...

  6. List of White Alice Communications System sites - Wikipedia

    en.wikipedia.org/wiki/List_of_White_Alice...

    The second segment of White Alice was a pair of TD-2 microwave radio links that supported the Ballistic Missile Early Warning System (BMEWS) at Clear Air Force Station. This section provided two routes from Alaska to NORAD in Colorado, for this reason it was also known as the Rearward Communications System . [ 3 ]

  7. Radar - Wikipedia

    en.wikipedia.org/wiki/Radar

    Radar is a system that uses radio waves to determine the distance (), direction (azimuth and elevation angles), and radial velocity of objects relative to the site. It is a radiodetermination method [1] used to detect and track aircraft, ships, spacecraft, guided missiles, motor vehicles, map weather formations, and terrain.

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    mail.aol.com

    Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!

  9. List of radars - Wikipedia

    en.wikipedia.org/wiki/List_of_radars

    AN/TPS-1 Long range search radar; AN/TPS-22 Long range search radar; AN/TPS-25 Ground Surveillance Radar (replaced by AN/TPS-58) AN/TPS-32 Long range search radar; AN/TPS-34 Long range search radar; AN/TPS-37 height-finder radar; AN/TPS-39 Intrusion Detection, missile sites [67] AN/TPS-43 Mobile Tactical 3D Radar; AN/TPS-43E Mobile Tactical 3D ...