A Doppler radar is a specialized radar that uses the Doppler effect to produce velocity data about objects at a distance. It does this by bouncing a microwave signal off a desired target and analyzing how the object's motion has altered the frequency of the returned signal. This variation gives direct and highly accurate measurements of the radial component of a target's velocity relative to the radar. Doppler radars are used in aviation, sounding satellites, Major League Baseball's StatCast system, meteorology, radar guns, radiology and healthcare, and bistatic radar.
An active electronically scanned array (AESA) is a type of phased array antenna, which is a computer-controlled array antenna 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).
A pulse-Doppler radar is a radar system that determines the range to a target using pulse-timing techniques, and uses the Doppler effect of the returned signal to determine the target object's velocity. It combines the features of pulse radars and continuous-wave radars, which were formerly separate due to the complexity of the electronics.
The AN/MPQ-64 Sentinel is a 3D radar used to alert and queue Short Range Air Defense (SHORAD) weapons to the locations of hostile targets approaching their front line forces. The Sentinel radar is deployed with forward area air defense units of the U.S. Army. It is an X-band range-gated, pulse-Doppler radar system. The antenna uses phase-frequency electronic scanning technology, forming sharp 3D pencil beams covering large surveillance and track volume. The radar automatically acquires, tracks, classifies, identifies and reports targets, including cruise missiles, unmanned aerial vehicles, and both rotary- and fixed-wing aircraft. It uses a high scan rate and operates at a range of 40 km (25 mi). The radar is designed with high resistance to electronic countermeasures (ECM). Mounted on a towed platform, it can be positioned remotely from the rest of the unit, operated autonomously and communicate with the Fire Distribution Center (FDC) via wideband fiber-optic link. It can also distribute its data over a SINCGARS radio network.
The Erieye radar system is an Airborne Early Warning and Control System (AEW&C) developed by Saab Electronic Defence Systems of Sweden. It uses active electronically scanned array (AESA) technology. The Erieye is used on a variety of aircraft platforms, such as the Saab 340 and Embraer R-99. It has recently been implemented on the Bombardier Global 6000 aircraft as the Globaleye.
An airport surveillance radar (ASR) is a radar system used at airports to detect and display the presence and position of aircraft in the terminal area, the airspace around airports. It is the main air traffic control system for the airspace around airports. At large airports it typically controls traffic within a radius of 60 miles (96 km) of the airport below an elevation of 25,000 feet. The sophisticated systems at large airports consist of two different radar systems, the primary and secondary surveillance radar. The primary radar typically consists of a large rotating parabolic antenna dish that sweeps a vertical fan-shaped beam of microwaves around the airspace surrounding the airport. It detects the position and range of aircraft by microwaves reflected back to the antenna from the aircraft's surface. In the US the primary radar operates at a frequency of 2.7 - 2.9 GHz in the S band with a peak radiated power of 25 kW and an average power of 2.1 kW. The secondary surveillance radar consists of a second rotating antenna, often mounted on the primary antenna, which interrogates the transponders of aircraft, which transmits a radio signal back containing the aircraft's identification, barometric altitude, and an emergency status code, which is displayed on the radar screen next to the return from the primary radar. It operates at a frequency of 1.03 - 1.09 GHz in the L band with peak power of 160 - 1500 W.
Type 517 radar is believed to be an A-band/VHF air search radar widely deployed on PLA-N surface vessels with 4 antennas in two crossed-brace supported pairs, one above the other, mounted in pairs on each side of a single tubular support carried on the turning gear.
The JY-9 Radar is a mobile S-band low altitude search radar intended for use in air defense, gap filling, airport surveillance and coastal defense. It is designed for effective detection of targets at low altitude in both ECM and natural clutter environments. The general designer of JY-9 is the head of 38th Research Institute, academician of Chinese Academy of Sciences Mr. Wu Manqing, who is also the general designer of JY-8 and the general designer of the radar systems for KJ-2000 and KJ-200.
CLC-1 short-range surveillance radar is a ground-based mobile tracking radar used by the People's Liberation Army of China.
The YLC-2 radar is a three-dimensional main guidance and surveillance radar developed by the Nanjing Research Institute of Electronics Technology.
YLC-6 is a series of two-dimensional radars from Nanjing Research Institute of Electronics Technology (NRIET) for mobile and static medium and low altitude surveillance.
YLC-15 is a fully coherent, Pulse Doppler air defence radar of Chinese origin. It is designed primarily to detect targets at ranges of up to 16 km. It also provides the capability to identify hovering helicopters or low altitude cruise missiles.
Radar engineering details are technical details pertaining to the components of a radar and their ability to detect the return energy from moving scatterers — determining an object's position or obstruction in the environment. This includes field of view in terms of solid angle and maximum unambiguous range and velocity, as well as angular, range and velocity resolution. Radar sensors are classified by application, architecture, radar mode, platform, and propagation window.
Radar MASINT is a subdiscipline of measurement and signature intelligence (MASINT) and refers to intelligence gathering activities that bring together disparate elements that do not fit within the definitions of signals intelligence (SIGINT), imagery intelligence (IMINT), or human intelligence (HUMINT).
The PJT-531 Battle Field Surveillance Radar – Short Range (BFSR-SR) is a man portable 2D short-range battlefield and perimeter surveillance radar developed by the Indian Defence Research and Development Organisation (DRDO). The BFSR has been designed by DRDO's Bangalore-based laboratory, the Electronics and Radar Development Establishment (LRDE) and is being manufactured by Bharat Electronics Limited (BEL).
The P-12 "Yenisei" was an early VHF developed and operated by the former Soviet Union.
The P-14 is a 2D VHF radar that was developed and operated by the Soviet Union.
The P-19 "Danube" 1RL134 is a 2D UHF radar developed and operated by the former Soviet Union. The radar was also known by the name "Renata" in Poland and "Dunai" in the former German Democratic Republic.
