Space Surveillance Always Tracking at the U.S. Army Kwajalein Atoll's Reagan Test Site
Hunt, Stephen M., Army
Radar, optical and telemetry sensors are operated at the U.S. Army Kwajalein Atoll's Reagan Test Site (RTS) to support missile testing, space surveillance operations and science experiments for DoD and the National Aeronautics and Space Administration (NASA).
The Reagan Test Site is located in the U.S. Army Kwajalein Atoll (USAKA), part of the Marshall Islands in the Pacific Ocean, approximately 4,000 kilometers southwest of Hawaii. The atoll consists of approximately 100 small islands resting on a coral reef formation 1,100 kilometers north of the geographic equator. The two largest islands are Kwajalein and Roi-Namur. High-power radars are located on Roi-Namur where they collect highly accurate metric (target position and velocity) and radar cross-section (target size and shape) data. These data are used to characterize missile reentry vehicles as well as help maintain the U.S. Strategic Command catalog of artificial satellites.
While each of the Reagan Test Site sensors contribute to space surveillance activities, the dominant contributors (tactically and routine) are the high-power all-weather radar systems. The four primary radars used for space surveillance are the Advanced Research Projects Agency (ARPA) long-range tracking and instrumentation radar (ALTAIR), target resolution and discrimination experiment (TRADEX) radar, ARPA Lincoln C-band observable radar (ALCOR) and millimeter wave (MMW) radar. ALTAIR and TRADEX are two-frequency radars that operate at UHF/VHP and L-band/S-band, respectively. ALTAIR has a 150-foot diameter mechanically steered dish antenna and is capable of transmitting a peak power of six million watts at each of its two frequencies.
TRADEX has an 84-foot diameter, mechanically steered dish antenna and is capable of transmitting a peak power of two million watts at each of its two frequencies. This combination of large antenna size and high power allows these radars to track small objects at large distances.
USAKA's support to the U.S. Strategic Command for the space surveillance mission consists of 128 tracking hours per week maintained with a 24-hours-a-day presence by the Reagan Test Site operations staff. Data are provided to U.S. Strategic Command on virtually every activity that takes place in space. Because of its Pacific-based equatorial location, the Reagan Test Site radars are immediately downrange of space launch facilities located in the former Soviet Union, China and Japan. Over half of the new launches out of these countries pass through ALTAIR's coverage in order to achieve orbit, and are detected and tracked at Reagan Test Site during their ascent.
This early coverage of launches from foreign launch facilities demands a continuous high state of readiness at the test site, defined by a 15-minute recall availability 24-hours-a-day, 365-days-a-year. The site is also involved in most domestic and cooperative launch programs, including the space shuttle, Atlas and Delta launches out of the Eastern and Western ranges and the European Space Agency Ariane program launched from French Guiana.
When not tracking new foreign or domestic launches, ALTAIR and TRADEX are members of a small exclusive group of radars capable of routinely tracking satellites in deep space, out to Earth's geosynchronous belt and beyond. The geosynchronous belt encircles earth's equator and is where spacecraft are placed so they essentially reside at a fixed location over the surface of the earth to perform their mission. …