Lockheed Martin recently announced that its Space Fence System, including the large-scale digital radar and turn-key facility, had met all the requirements of the program’s Critical Design Review (CDR).
It was in 2011 that Lockheed Martin was awarded a contract to develop a prototype radar system to track resident space objects. It is hoped that Space Fence will enable the decommissioning of the U.S.-based Air Force Space Surveillance System (AFSSS) that was originally installed in 1961 when just about all the objects in space originated from somewhere other than Earth. Currently, by some estimates there are 60 nations operating in space, and hundreds of thousands of Earth-borne objects orbiting in space.
U.S. Air Force representatives and Lockheed Martin engineers reviewed the Space Fence S-band radar system design, which was developed to detect, track, and catalog orbital objects in space more than 1.5 million times a day to predict and prevent space-based collisions. The three-day CDR was preceded by the delivery of 21,000 pages of design documents, and an eight-day Design Walkthrough, to ensure the system will meet performance requirements. The CDR event featured the demonstration of a small-scale system built with end-item components that detected and tracked orbiting space objects.
“Completion of CDR marks the end of the design phase and the start of radar production and facility construction of the Space Fence system,” said Steve Bruce, Vice President for Advanced Systems at Lockheed Martin’s Mission Systems and Training business. "Once complete, Space Fence will [offer] a flexible system capable of adapting to future missions requiring new tracking and coverage approaches.”
Within the Space Fence radar open architecture design, Lockheed Martin uses monolithic microwave integrated circuit technology, including gallium nitride (GaN) semiconductor materials. The company says GaN provides a number of significant advantages for active phased array radar systems, including higher power density, greater efficiency, and significantly improved reliability over previous technologies.
Lockheed Martin has been involved with the development of GaN-based products for at least ten years. It is able to procure mature technology that is commercially available, aided by investment in consumer electronics-type areas such as cell phone infrastructure and LED design. It says this is in alignment with the recent release of Better Buying power 3.0 and the need to leverage commercial technology where applicable to lower development costs and provide greater value for the Department of Defense.
In addition to engineering the radar arrays, the Lockheed Martin team also broke ground on the new six-acre Space Fence site earlier this year on Kwajalein Island, 2100 mi southwest of Honolulu. The construction process is challenging due to the remoteness and cultural and historic significance of the location. The buildings are designed to handle high winds and seismic loads, while maintaining the alignment and accuracy of the radar system.
The sensor site installation will include an on-site operations center and an annex to the current island power plant that will ensure the Space Fence system has everything necessary to provide continuous space situational awareness. Once construction is complete, Space Fence will go through testing and validation before its initial operating capability occurs in late 2018.