AN/FPS-117

AN/FPS-117

An Australian AN/TPS-77 in 2007
Country of origin	United States
Manufacturer	Lockheed Martin
Introduced	1980
Type	Phased array Long-Range Radar System
Frequency	1215 to 1400 MHz (D/L)
PRF	241
Pulsewidth	51.2 / 409.6 μs
RPM	5 - 6 RPMs
Range	470 km (250 nmi)
Altitude	30.5 km (100,000 ft)
Azimuth	0.18° at 250 km
Elevation	-6° to +20°
Power	24.6 kW
Other Names	Seek Igloo, AN/TPS-59, AN/TPS-77, AN/TPS-177, RRS-177, AMES Type 92

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.

The system was originally developed as part of the "Seek Igloo/Seek Frost" effort to replace the older radar systems of the DEW line with designs that could be operated remotely and require much less maintenance as part of DEW's replacement, the American-Canadian North Warning System (NWS). Implementation of the NWS resulted in a reduction in operations and maintenance spending by up to 50% compared to previous systems.

GE made a number of modifications to the basic design to better tailor it to different roles. To fill a need for the US Marine Corps, GE developed the transportable AN/TPS-59, and later combined design elements to produce the smaller AN/TPS-77 which is even more mobile, requiring only one prime mover in some deployment scenarios. FPS-117s, modified with input from Siemens for German service are known as the RRP-117, while the TPS-77s in service with the Royal Air Force are known as the AMES Type 92. An even smaller version was introduced by Lockheed Martin as the TPS-77 MRR.