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An Australian AN/TPS-77 in 2007
|Country of origin||United States|
|Type||Long-Range Radar System|
|Frequency||1215 to 1400 MHz (D/L)|
|Pulsewidth||51.2 / 409.6 μS|
|RPM||5 or 6 RPMs|
|Range||470 km (250 nmi)|
|Altitude||30.5 km (100,000 ft)|
|Azimuth||0.18° at 250 km|
|Elevation||-6° to +20°|
The system is a low power, long range (200-250 nautical miles), L-band pencil beam, solid-state transmitter and beacon interrogator search radar. System design includes a redundant architecture with computer software remote controlled and monitored operations to minimize manning requirements.
The AN/FPS-117 is in use as part of the American-Canadian North Warning System of radars stretching across North America from Alaska, USA to Labrador, Canada. This North Warning System is designed to provide long-range detection and coverage for drug interdiction support and tactical command and control.
Implementation of the North Warning System has resulted in a reduction in Operations and Maintenance (O&M) spending by up to 50% compared to previous systems. Due to extreme northern locations of these radars, the physics of radiowave propagation in the 1215-1400 MHz frequency range is even more critical for target detection requirements. The Air Force and the FAA also operate a limited number of AN/FPS-117 radars within the continental United States. The AN/FPS-117 radar is capable of randomly hopping among 18 channels in the 1215-1400 MHz band.
In 2011, Lockheed Martin was awarded a contract to upgrade the radars to extend their operational lives through 2025.
Originally selected for the Alaskan Air Command's SEEK IGLOO project, the radar was also picked to replace the United States Air Force's AN/FPS-67 radar at Berlin's Tempelhof Central Airport and was commissioned at Tempelhof in July 1984.
- Canada - Used in North Warning System
- Estonia - Used in Baltic Air Surveillance Network 
- Germany - Uses German variant RRP-117
- Latvia - Used in Baltic Air Surveillance Network
- Lithuania - Used in Baltic Air Surveillance Network
- Saudi Arabia
- South Korea - Used on Ulleungdo Island to defend Liancourt Rocks from a territorial dispute with Japan, and on the Korean Demilitarized Zone.
- United Kingdom
- United States - Used in North Warning System 
- AN/FPS-117 - Standard fixed version produced by Lockheed Martin.
- AN/TPS-77 - Transportable version produced by Lockheed Martin.
- RRP-117 - German fixed variant produced by Lockheed Martin, modified by Siemens to meet Luftwaffe requirements.
|Wikimedia Commons has media related to AN/FPS-117.|
- Lockheed Martin. "AN/FPS-117 LONG-RANGE AIR SURVEILLANCE RADARS" (PDF). Retrieved 2013-10-13.
- "AN/FPS-117". Radomes. Retrieved September 5, 2017.
- "AN/FPS Series". alternatewars.com. Retrieved 2013-10-13.
- "Lockheed Martin to Modernize 29 U.S. Air Force Early Warning Long-Range Surveillance Radars." Archived November 8, 2011, at the Wayback Machine. Lockheed Martin, 7 November 2011.
- ""The Baltic Air Surveillance Network - BALTNET"". Archived from the original on 2008-06-03. Retrieved 2008-06-03.
- "Bundeswehr baut auf dem Flughafen Tempelhof (Bundeswehr is building at Tempelhof Airport)". Berliner Morgenpost. September 4, 2009. Retrieved September 4, 2017.
- "AN/FPS-117 Long Range Radar Upgrade". ASD News. December 26, 2008. Retrieved September 2, 2017.
- John Keller (December 12, 2012). "Lockheed Martin to continue project to upgrade AN/FPS-117 long-range surveillance radars". Military & Aerospace Electronics. Retrieved September 2, 2017.
- "RRP-117 "Seek Igloo"". Retrieved 2017-09-14.[dead link]