Search results
Results from the WOW.Com Content Network
Over-the-horizon radar (OTH), sometimes called beyond the horizon radar (BTH), is a type of radar system with the ability to detect targets at very long ranges, typically hundreds to thousands of kilometres, beyond the radar horizon, which is the distance limit for ordinary radar. Several OTH radar systems were deployed starting in the 1950s ...
This is an incomplete list of ground-based radars operated by the United States Marine Corps since the service first started utilizing radars in 1940. [1] The Marine Corps' has used ground-based radars for anti-aircraft artillery fire control, long range early warning, Ground-controlled interception (GCI), ground directed bombing, counter-battery radar, short-range cueing for man-portable air ...
The AN/FPS-117 is an L-band active electronically scanned array (AESA) 3-dimensional air search radar first produced by GE Aerospace in 1980 and now part of Lockheed Martin. [1] [2] The system offers instrumented detection at ranges on the order of 200 to 250 nautical miles (370 to 460 km; 230 to 290 mi) and has a wide variety of interference and clutter rejection systems.
Only four units were produced in favour of microwave systems. [10] When the microwave systems arrived, they required two separate radars, one for PPI direction and separate systems for height finding. The system massed 35 long tons (36 t) compared to the 2 long tons (2.0 t) limit for operations in the South Pacific.
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.
In over-the-horizon radar, ducting causes part of the radiated and target-reflection energy of a radar system to be guided over distances far greater than the normal radar range. It also causes long-distance propagation of radio signals in bands that would normally be limited to line of sight.
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!
A radically different type of antenna for X-band systems was invented by Luis W. Alvarez and used in three new systems: an airborne mapping radar called Eagle, a blind-landing Ground Control Approach (GCA) system, and a ground-based Microwave Early-Warning (MEW) system. The latter two were highly successful and carried over into post-war ...