Question: Where are the headquarters of the company that developed the AN/APQ-159, an I band/J band radar system?
Context: In infrared astronomy, the J band refers to an atmospheric transmission window centred on 1.25 micrometres (in the near-infrared).  Betelgeuse is the brightest near-IR source in the sky with a J band magnitude of −2.99.  The next brightest stars in the J band are Antares (−2.7), R Doradus (−2.6), Arcturus (−2.2), and Aldebaran (−2.1).  In the J band Sirius is the 9th brightest star. AIRPASS (Airborne Interception Radar & Pilot's Attack Sight System) was an early British airborne interception radar and fire-control radar system developed by Ferranti.  It was the world's first airborne monopulse radar system, and provided cueing to the world's first true heads up display. Emerson Electric's AN/APQ-159 was an I band/J band radar designed to upgrade Emerson's simple AN/APQ-153 used in the Northrop F-5.  It offered roughly double the range, increased off-boresight tracking angles, and considerably improved reliability.  Originally intended to be replaced by the further improved AN/APQ-167, modernized F-5s have typically moved to the entirely new AN/APG-69 instead. The Mount Fuji Radar System is a historic weather radar system located on the summit of Mount Fuji, Japan.  It was completed on August 15, 1964 , and is now recorded on the list of IEEE Milestones in electrical engineering.  When first built, the Mount Fuji Radar System was the world's highest weather radar (elevation 3776 meters), and could observe major weather phenomena, such as destructive typhoons, at a range of more than 800 kilometers.  It was designed by the Japan Meteorological Agency and built by Mitsubishi Electric Corporation. Type 984 radar was a British radar system introduced in the mid-1950s.  It was a rotating mechanically stabilized 3D S band radar, measuring longitudinal position, latitudinal position, as well as target altitude, devised by the Admiralty Signals Research Establishment.  It did this by creating a stack of vertically scanning beams.  It had one stationary beam, as well as five scanning beams fed by four magnetrons. ASR-9 is an airport surveillance radar system admitted into the National Airspace System (NAS), to be utilized by the Federal Aviation Administration to monitor civilian and commercial air traffic within the United States.  Developed by Westinghouse, ASR-9 was the first radar system to display air traffic, and weather conditions simultaneously.  The ASR-9 is mainly intended to monitor and track aircraft below 25,000 ft and within forty to sixty nautical miles from the airport of operation.  The ASR radar systems were widely used where an advanced radar system was needed, consisting of 135 different ASR-9 operating locations around the U.S.  The FAA is currently working to upgrade the remaining ASR-9 radar sites to a modernized digital version known as the ASR-11. The Tracking & Imaging Radar (TIRA) system serves as the central experimental facility for the development and investigation of radar techniques for the detection and reconnaissance of objects in space, and to a certain degree also of air targets.  TIRA has a 34-metre parabolic dish antenna is a monopulse radar operating at 1.333 GHz or 22.5 cm (L band) and 16.7 GHz or 1.8 cm (Ku band) wavelengths.  The L-band is usually used for tracking debris with a 0.45° beam width, at 1 MW peak power.  The system is capable of determining orbits from direction angles, range and Doppler shift for single targets.  The detection size threshold is about 2 cm at 1000 km range.  The radar conducts regular ‘beam park’ experiments, where the radar beam is pointed in a fixed direction on the celestial sphere for 24 hours, scanning 360° in a narrow strip a complete Earth rotation.  The tracking sensitive can be enhanced when the TIRA system is used as a transmitter, part of a bistatic radar system.  In conjunction with the Effelsberg Radio Telescope, functioning as a receiver, the combined system has a detection size threshold of 1 cm.  The Ku-band is used for imaging in Inverse Synthetic Aperture Radar (ISAR) mode, with 13 kW peak power, the radar is capable of producing images with range resolutions better than 7 cm.  The dish can be turned full 360° in azimuth with speed of 24° per second and 90° in elevation.  The radar is protected by a radome with 47 meters diameter - one of the largest in the world. Emerson Electric's AN/APQ-153 was an I band radar system developed for the Northrop F-5E fighter aircraft.  Required to fit into the tight confines of the originally radar-less F-5, the system offered relatively simple air-to-air modes and a short detection range.  The AN/APQ-157 was a similar system with dual displays and controls for the twin-seat F-5F trainer.  Many of the F-5's still flying have been upgraded to the improved AN/APQ-159. The AN/APQ-181 is an all-weather, low probability of intercept (LPI) 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 K 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. The Emerson Electric Company () is an American multinational corporation headquartered in Ferguson, Missouri, United States.  This Fortune 500 company manufactures products and provides engineering services for a wide range of industrial, commercial, and consumer markets.
Answer: Ferguson, Missouri, United States.