AN/APQ-181

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Light surface below wing edges is the AN/APQ-181 radar antenna B-2 radar.jpg
Light surface below wing edges is the AN/APQ-181 radar antenna

The AN/APQ-181 is an all-weather, low probability of intercept (LPI) phased array radar system designed by Hughes Aircraft (now Raytheon) for the U.S. Air Force B-2A Spirit bomber aircraft. The system was developed in the mid-1980s and entered service in 1993. The APQ-181 provides a number of precision targeting modes, and also supports terrain-following radar and terrain avoidance. The radar operates in the Ku band (a subset of the J band). The original design uses a TWT-based transmitter with a 2-dimensional passive electronically scanned array (PESA) antenna.

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In 1991, the B-2 Industrial Team (including Hughes as a major subcontractor) was awarded the Collier Trophy in recognition of the "design, development, production, and flight testing of the B-2 aircraft, which has contributed significantly to America's enduring leadership in aerospace and the country's future national security."

In 2002, Raytheon was awarded a contract to develop a new, active electronically scanned array (AESA) version of the APQ-181. This upgrade will improve system reliability, and will also eliminate potential conflicts in frequency usage between the B-2 and commercial satellite systems that also use the J band.

In 2008 the Federal Communications Commission accidentally sold the APQ-181 frequency to a commercial user resulting in the need for installing new radar arrays at a cost of over $1 billion. All B-2 aircraft are expected to have the upgraded radar by 2010. [1]

See also

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<span class="mw-page-title-main">Raytheon</span> U.S. defense contractor

The Raytheon Company was a major U.S. defense contractor and industrial corporation with manufacturing concentrations in weapons and military and commercial electronics. It was previously involved in corporate and special-mission aircraft until early 2007. Raytheon was the world's largest producer of guided missiles. In April 2020, the Raytheon Company merged with United Technologies Corporation to form Raytheon Technologies, which changed its name to RTX Corporation in July 2023.

<span class="mw-page-title-main">Active electronically scanned array</span> Type of phased array radar

An active electronically scanned array (AESA) is a type of phased array antenna, which is a computer-controlled antenna array in which the beam of radio waves can be electronically steered to point in different directions without moving the antenna. In the AESA, each antenna element is connected to a small solid-state transmit/receive module (TRM) under the control of a computer, which performs the functions of a transmitter and/or receiver for the antenna. This contrasts with a passive electronically scanned array (PESA), in which all the antenna elements are connected to a single transmitter and/or receiver through phase shifters under the control of the computer. AESA's main use is in radar, and these are known as active phased array radar (APAR).

<span class="mw-page-title-main">AN/MPQ-64 Sentinel</span> American short-range air defense radar

The AN/MPQ-64 Sentinel is an X-band electronically steered pulse-Doppler 3D radar system used to alert and cue Short Range Air Defense (SHORAD) weapons to the locations of hostile targets approaching their front line forces. It is currently produced by Raytheon Missiles & Defense.

<span class="mw-page-title-main">Terrain-following radar</span> Radar used for extremely low level flight

Terrain-following radar (TFR) is a military aerospace technology that allows a very-low-flying aircraft to automatically maintain a relatively constant altitude above ground level and therefore make detection by enemy radar more difficult. It is sometimes referred to as ground hugging or terrain hugging flight. The term nap-of-the-earth flight may also apply but is more commonly used in relation to low-flying military helicopters, which typically do not use terrain-following radar.

<span class="mw-page-title-main">AN/APG-63 radar family</span> Military aircraft all-weather multimode radar family

The AN/APG-63 and AN/APG-70 are a family of all-weather multimode radar systems designed by Hughes Aircraft for the F-15 Eagle air superiority fighter. These X band pulse-Doppler radar systems are designed for both air-air and air-ground missions; they are able to look up at high-flying targets and down at low-flying targets without being confused by ground clutter. The systems can detect and track aircraft and small high-speed targets at distances beyond visual range down to close range, and at altitudes down to treetop level. The radar feeds target information into the aircraft's central computer for effective weapons delivery. For close-in dogfights, the radar automatically acquires enemy aircraft and projects this information onto the cockpit head-up display. The name is assigned from the Army Navy Joint Electronics Type Designation System.

The AN/ALR-67 radar warning receiver is designed to warn an aircraft's crew of potentially hostile radar activity. It is an airborne threat warning and countermeasures control system built to be successor to the United States Navy's AN/ALR-45. Northrop Grumman Corporation's Electronic Systems sector was the main contractor for the AN/ALR-67(V) and (V)2. Raytheon Electronic Warfare Systems was the main contractor for the AN/ALR-67(V)3.

<span class="mw-page-title-main">AN/AWG-9</span> X band pulse-Doppler military aircraft radar

The AN/AWG-9 and AN/APG-71 radars are all-weather, multi-mode X band pulse-Doppler radar systems used in the F-14 Tomcat, and also tested on TA-3B. It is a long-range air-to-air system capable of guiding several AIM-54 Phoenix or AIM-120 AMRAAM missiles simultaneously, using its track while scan mode. The AWG-9 utilizes an analog computer while the APG-71 is an upgraded variant utilizing a digital computer. Both the AWG-9 and APG-71 were designed and manufactured by Hughes Aircraft Company's Radar Systems Group in Los Angeles; contractor support was later assumed by Raytheon. The AWG-9 was originally created for the canceled Navy F-111B program.

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<span class="mw-page-title-main">AN/APG-77</span> Type of radar system

The AN/APG-77 is a multifunction low probability of intercept radar installed on the F-22 Raptor fighter aircraft. The radar was designed and initially built by Westinghouse and Texas Instruments, and production continued with their respective successors Northrop Grumman and Raytheon after acquisition.

The AN/APG-76 radar is a pulse Doppler Ku band multi-mode radar developed and manufactured by Northrop Grumman.

The AN/SPY-3 is an active electronically scanned array radar manufactured by Raytheon and designed for both blue-water and littoral operations.

<span class="mw-page-title-main">Passive electronically scanned array</span> Type of antenna

A passive electronically scanned array (PESA), also known as passive phased array, is an antenna in which the beam of radio waves can be electronically steered to point in different directions, in which all the antenna elements are connected to a single transmitter and/or receiver. The largest use of phased arrays is in radars. Most phased array radars in the world are PESA. The civilian microwave landing system uses PESA transmit-only arrays.

<span class="mw-page-title-main">AN/TPQ-37 Firefinder radar</span> US mobile counter-battery radar system

Hughes AN/TPQ-37 Firefinder Weapon Locating System is a mobile radar system developed in the late 1970s by Hughes Aircraft Company, achieving Initial Operational Capability in 1980 and full deployment in 1984. Currently manufactured by ThalesRaytheonSystems, the system is a long-range version of "weapon-locating radar", designed to detect and track incoming artillery and rocket fire to determine the point of origin for counter-battery fire. It is currently in service at brigade and higher levels in the United States Army and by other countries. The radar is trailer-mounted and towed by a 2+13-short-ton (2,100 kg) truck. A typical AN/TPQ-37 system consists of the Antenna-Transceiver Group, Command Shelter and 60 kW Generator.

<span class="mw-page-title-main">AN/APG-81</span> Radar system

The AN/APG-81 is an active electronically scanned array (AESA) fire-control radar system designed by Northrop Grumman Electronic Systems for the Lockheed Martin F-35 Lightning II.

The AN/APG-67 is a multi-mode all-digital X band coherent pulse doppler radar originally developed by General Electric for the Northrop F-20 Tigershark program of the early 1980s. It offers a variety of air-to-air, air-to-ground, sea-search and mapping modes, and compatibility with most weapons used by the US Air Force in the 1980s.

The AN/APG-83 Scalable Agile Beam Radar (SABR) is a full-performance active electronically scanned array (AESA) fire control radar for the General Dynamics F-16 Fighting Falcon and other aircraft developed by Northrop Grumman. In a 2013 competition, Lockheed Martin selected SABR as the AESA radar for the F-16 modernization and update programs of the United States Air Force and Republic of China Air Force.

<span class="mw-page-title-main">AN/SPY-1</span> Passive electronically scanned radar system

The AN/SPY-1 is a United States Navy passive electronically scanned array (PESA) 3D radar system manufactured by Lockheed Martin, and is a key component of the Aegis Combat System. The system is computer controlled and uses four complementary antennas to provide 360-degree coverage. The system was first installed in 1973 on USS Norton Sound and entered active service in 1983 as the SPY-1A on USS Ticonderoga. The -1A was installed on ships up to CG-58, with the -1B upgrade first installed on USS Princeton in 1986. The upgraded -1B(V) was retrofitted to existing ships from CG-59 up to the last, USS Port Royal.

<span class="mw-page-title-main">AN/APQ-120</span> Aircraft fire control radar

The AN/APQ-120 was an aircraft fire control radar (FCR) manufactured by Westinghouse for the McDonnell Douglas F-4E Phantom II. AN/APQ-120 has a long line of lineage, with its origin traced all the way back to Aero-13 FCR developed by the same company in the early 1950s. A total of half a dozen FCRs were tested and evaluated on the first 18 F-4s built, but they were soon replaced by later radars produced in great numbers, including AN/APQ-120.

References

  1. "Bandwidth Demands Crowd Military Needs". military.com. Archived from the original on March 26, 2009.