Reagan Test Site
The U.S. Army's Reagan Test Site (RTS), approximately 2,300 miles west southwest of Hawaii on the Kwajalein Atoll in the Marshall Islands, is a world-class range and test facility. In operation for nearly 50 years, the RTS is ideal for missile and interceptor testing because of its distance from populous areas and its open-ocean line from launch facilities at Vandenberg Air Force Base in California. The site's unique instrumentation systems, including high-fidelity metric signature radars and optical sensors, support research, development, test, and evaluation of technology for ballistic missile defense and space surveillance. Each year, Department of Defense agencies execute many tests to study the flight characteristics and capabilities of missiles, interceptors, and satellites, and to verify their functionality, efficiency, and reliability.
MIT Lincoln Laboratory, as the scientific advisor to the RTS, supports operations at the range and conducts upgrades to the sensors and command-and-control infrastructure. A resident team of Laboratory staff and government subcontractors operate the four radars located at the Kiernan Reentry Measurements Site on Roi-Namur Island on the Kwajalein Atoll. About 20 Laboratory personnel are stationed on Kwajalein Atoll at any given time, serving two- to three-year tours before returning to the Laboratory.
During the late 1990s and 2000s, the Laboratory helped modernize the radar suite at RTS, applying an open system architecture that enabled the radar systems to be remotely operated from the RTS headquarters on Kwajalein Island and that decreased the cost and manpower needed to operate the radar. In recent years, the Laboratory developed new software tools that provide mission controllers with automated decision support for directing sensors during increasingly complex tests conducted at the RTS. Two years ago, the Laboratory introduced several upgrades to the RTS optical suite, which enabled remote operation of the optical systems and radars from the U.S. Army Space and Missile Command in Huntsville, Alabama.
The Target Resolution and Discrimination Experiment (TRADEX) system was the first of the radars to be built at Kwajalein for Project PRESS (Pacific Range Electromagnetic Signature Studies). The radar became operational in 1962, the same year the first Lincoln Laboratory staff arrived to live on Kwajalein Island. Early on, TRADEX was used to track and collect data on missiles for test missions. An upgrade to the radar in 1995 enabled TRADEX to assess the space-debris population at low latitudes. This mode was used to collect space-debris data for NASA. In 1998, TRADEX became a contributing sensor to the U.S. Space Surveillance Network, with a primary focus on tracking foreign launches, deep-space satellites, and low Earth-orbit satellites. TRADEX currently operates for the space surveillance mission for 10 hours a week.
The second of the RTS radars, the ARPA Long-Range Tracking and Instrumentation Radar (ALTAIR), became operational in 1969. ALTAIR was designed primarily to give the United States a view of how U.S. intercontinental ballistic missiles would appear to Soviet anti-ballistic-missile radars. In 1998, ALTAIR and TRADEX were used to make the first-of-its kind measurements on the Perseid and Leonid meteor showers to understand how meteors could impact spacecraft. ALTAIR joined the Space Surveillance Network in 1982. Like TRADEX, ALTAIR is responsible for tracking foreign launches, and near-Earth-orbit and deep-space satellites. Today, ALTAIR dedicates 128 hours per week to the space surveillance mission, typically providing more than 1000 deep-space tracks each week.
A year after ALTAIR, the ARPA Lincoln C-band Observables Radar (ALCOR) became operational. It was the first high-power microwave radar to utilize wideband waveform transmissions. ALCOR was built with the objective of being able to generate and process wide-bandwidth signals and to investigate the applications of broadband data for reentry vehicle discrimination and space situational awareness. Not only was ALCOR's wideband capability effective for producing high-resolution data on missiles, but it also proved to be extremely useful for determining the size and shape of orbiting near-Earth satellites. The ALCOR system was eventually adapted to satellite imaging, leading to Lincoln Laboratory's pioneering work in developing techniques and algorithms for generating and interpreting radar images.
The Millimeter Wave (MMW) radar became operational in 1983 and was the last built radar at the RTS. The original charter for the MMW was to provide a database of millimeter-wave signature data of missile reentry phenomenology. Initially designed as an adjunct to ALCOR, the MMW has since grown to become a complete, self-sufficient system. The MMW has the best range resolution of the radars at Kwajalein and is capable of generating high-resolution images of near-Earth satellites. Over the years, the MMW went through a series of upgrades, including a component replacement effort in the early 1990s that enabled much higher transmitter power levels. Further upgrades in 2011 made the MMW the highest-resolution coherent instrumentation radar in operation today.