Haystack LRIR

The Haystack radar is large dish radar at the Lincoln Space Surveillance Center near Boston, and a contributing sensor to the U.S. Space Surveillance Network.[1]  From 1978 until April 2010, when it was shut down for a major upgrade to add a W-Band capability (which will be discussed in a future post), Haystack operated part-time as the X-Band Long-Range Imaging Radar (LRIR).  The LRIR was reportedly the only U.S. radar capable of imaging satellites out to geosynchronous orbit range.  The upgrade involved installing a new antenna and was due to be completed by about 2013, after which the radar will be known as the Haystack Ultrawideband Space Imaging Radar (HUSIR).  Under the upgrade, the LRIR’s X-band capability will be retained and is expected to return to operation in 2012.

September 2010: The top portion of the Haystack’s radome about to be reinstalled after the installation of the new antenna.  Photograph from MIT Lincoln Laboratory, 2010 Annual Report, p. 13.[2]

(more…)

ALCOR

ALCOR (ARPA Lincoln C-Band Observables Radar) was the world’s first high-power long-range wide-band radar.[1]  It played a key role in the development and early implementation of range-Doppler techniques for imaging satellites, producing images with a resolution of 0.5 meters (about 20 inches). ALCOR began operations at Kwajalein in late 1969.  Although it has since been exceeded in both range and resolution capabilities by the Millimeter Wave (MMW) Radar at the same Kwajalein site (and by other wide-band radars at other sites), it remains an important collateral sensor in the Space Surveillance Network.[2]  

 The ALCOR antenna viewed from behind inside its radome at Kwajalein. (Photograph from Camp, et.al.,  Lincoln Laboratory Journal)

(more…)

pALTAIR (ARPA Long-Range Tracking and Instrumentation Radar) is a large steerable dish-array radar at the U.S. ballistic missile test range on Kwajalein in the Pacific Ocean.[1]  Operating at both VHF and UHF frequencies, it is an important collateral sensor in the U.S. Space Surveillance Network, particularly for detecting and tracking newly-launched satellites and for tracking objects in deep-space and geosynchronous orbits.  Together with the Millstone Hill and GLOBUS II radars, ALTAIR provides complete coverage of the geosynchronous belt.

Background

The four SSN radars at Kwajalein.  The ALTAIR antenna is the large dish at upper center, viewed partially against the lagoon.  The antenna for TRADEX, which backs up ALTAIR in the Space Surveillance Network (SSN), is the dish antenna on top of the building near the center of the picture.  The antenna for the ALCOR imaging radar is in the dome at lower left, and the antenna for the MMW imaging radar is in the dome in the center of the picture between the ALTAIR and TRADEX antennas.  (Photograph from http://www.orbitaldebris.jsc.nasa.gov/measure/radar.html.)

(more…)

The Millstone Hill Radar

The Millstone Hill Radar (MHR) is a large (84 foot diameter) L-Band dish tracking radar located, appropriately enough, on Millstone Hill in Westford MA, a suburb of Boston (42.62˚ N, 71.49˚ W).[1]  It is an important contributing sensor in the Space Surveillance Network (SSN) and is used both for near- and deep-space surveillance.  Two other SSN contributing sensors, the Haystack Radar and the Haystack Auxiliary Radar, which are primarily imaging radars, are located at essentially the same site, and all three are operated by Lincoln Laboratories.  The MHR should not be confused with two other radars at the same site and sometimes also referred to as Millstone Hill radars, one with a 220 foot fixed zenith-pointing antenna and the other with a 150 steerable dish antenna.  Both of these radars operate in the UHF Band and are used almost exclusively for scientific (ionospheric) research, although the steerable dish serves as a backup to MHR for space surveillance purposes.

(more…)

Tabular Overview of SSN Phased Array Radars

For details and references, see posts on individual systems.

(more…)

PAVE PAWS

Background                                                                                                                            

Two PAVE PAWS (FPS-115) ballistic missile early warning radars are located on Cape Cod, Massachusetts (41.75˚E, 70.54˚W, oriented east), and at Beale Air Force Base in California (39,14˚N, 121.35˚W, oriented west).  A third radar, the BMEWS (Ballistic Missile Early Warning System) radar at Clear, Alaska (64.30˚N, 149.19˚W, oriented north) appears to be essentially identical to the two PAVE PAWS and so is discussed with them. All three radars are collateral sensors in the SSN.   PAVE PAWS radars in Georgia and Texas were deactivated in the mid-1980s and parts from these radars were used in building the Alaska radar. 

(more…)

Background

Cobra Dane (AN/FPS-108) is a large and powerful phased-array radar located on Shemya Island at the western end of the Aleutian Island chain (52.7º N, 174.1º E).[1]  The radar’s boresite is at 319º (that is 41º west from due north) at 20º above the horizon. Its primary mission when deployed was the monitoring of Soviet ballistic missile test flights, with secondary missions of early warning and space surveillance.  It became operational in 1977, and underwent a modernization in the early 1990s and a number of enhancements subsequently. 

(more…)

Background

The PARCS radar (AN/FPQ-16), located at Cavalier Air Force Station in Northern North Dakota (48.7˚ N, 97.9˚ W), was built as part of the Safeguard ballistic missile defense system, in which it was known as the Perimeter Acquisition Radar Attack Characterization System (PARCS).[1]  When Safeguard was shut down in early 1976, after only a few months of operation, the radar continued to operate in missile warning (its new primary mission) and satellite tracking modes.  The radar is a collateral sensor in the SSN network.

(more…)

Background

The FPS-85 has been described as the workhorse of the SSN, and is the largest, most sensitive and most important (for space surveillance purposes) of the SSN’s LPARs.  It is one of the three dedicated radar sensors in the SSN (the others are the Air Force Fence and the GLOBUS II dish antenna radar in Norway).  The radar is located in Eglin, Florida (and thus sometimes referred to as the Eglin Radar) at about 30.6° N (30.57N, 86.22 E) and points directly south. 

(more…)