|Country of origin||Soviet Union|
|Precision||0.3 km range|
The P-15"Tropa" (Russian : "Тропа"; English: "trail") or 1RL13 (also referred to by the NATO reporting name "Flat Face A" in the west) is a 2D UHF radar developed and operated by the former Soviet Union.
In 1952 SRI-244 started development of what become the P-15 early warning radar; by 1955, the radar had passed state trials and was accepted into service with the anti-aircraft troops of the Soviet armed forces.The P-15 was designed to detect aircraft flying at low altitude and came to be associated with the S-125 "Neva" anti-aircraft system (NATO reporting name SA-3 "Goa"), though it was later replaced by the P-15M2 "Squat Eye" radar which mounted a single radar antenna on a 20-30 meter mast to improve coverage.
In 1959, the modernised P-15M "trail" radar passed through the state test program, the modernisation replacing outdated mercury-based electronics. In 1962, another modernisation of the P-15 passed through trials as the P-15N, the radar being developed and produced by the Ulyanovsk Mechanical Plant. dB), the first such radar in the Soviet Union. Finally by 1974, the modernisation of the P-15 was so extensive that it resulted in a new designation, the P-19 "Danube", also known as the 1RL134. The P-19 is known in the west as the Flat Face B.The P-15N introduced a more sensitive receiver, which improved the detection range and a new amplifier for the transmitter. Further improvements were made in 1970 when the P-15MN passed trials. The P-15MN included a pulse coherent Doppler filter (moving target indicator) to remove passive clutter (by up to 50
The P-15 is a high mobility radar. With the antenna mounted directly on the single truck (Zil-157) used for transport, the system could be deployed and taken down in no more than 10 minutes.The P-15 uses two open frame elliptical parabolic antenna accomplishing both transmission and reception, each antenna being fed by a single antenna feed. The radar can rapidly shift its frequency to one of four pre-set frequencies to avoid active interference, with passive interference being removed by a coherent doppler filter. Azimuth was determined by mechanical scanning with an associated accompanying PRV-11 (NATO reporting name "Side Net") used to determine elevation. A secondary radar for IFF is generally used in conjunction with the P-15, generally the 1L22 "Parol".
The P-15 was operated by the Soviet Union from 1955. It has since become obsolete, but it was passed down to successor states after the fall of the Soviet Union. It has been largely superseded by its successor the P-19.
Radar is a detection system that uses radio waves to determine the distance (range), angle, or velocity of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. A radar system consists of a transmitter producing electromagnetic waves in the radio or microwaves domain, a transmitting antenna, a receiving antenna and a receiver and processor to determine properties of the object(s). Radio waves from the transmitter reflect off the object and return to the receiver, giving information about the object's location and speed.
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.
Synthetic-aperture radar (SAR) is a form of radar that is used to create two-dimensional images or three-dimensional reconstructions of objects, such as landscapes. SAR uses the motion of the radar antenna over a target region to provide finer spatial resolution than conventional beam-scanning radars. SAR is typically mounted on a moving platform, such as an aircraft or spacecraft, and has its origins in an advanced form of side looking airborne radar (SLAR). The distance the SAR device travels over a target in the time taken for the radar pulses to return to the antenna creates the large synthetic antenna aperture. Typically, the larger the aperture, the higher the image resolution will be, regardless of whether the aperture is physical or synthetic – this allows SAR to create high-resolution images with comparatively small physical antennas. Additionally, SAR has the property of having larger apertures for more distant objects, allowing consistent spatial resolution over a range of viewing distances.
The history of radar started with experiments by Heinrich Hertz in the late 19th century that showed that radio waves were reflected by metallic objects. This possibility was suggested in James Clerk Maxwell's seminal work on electromagnetism. However, it was not until the early 20th century that systems able to use these principles were becoming widely available, and it was German inventor Christian Hülsmeyer who first used them to build a simple ship detection device intended to help avoid collisions in fog. True radar, such as the British ‘Chain Home’ early warning system provided directional information to objects over short ranges, were developed over the next two decades.
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.
Passive radar systems encompass a class of radar systems that detect and track objects by processing reflections from non-cooperative sources of illumination in the environment, such as commercial broadcast and communications signals. It is a specific case of bistatic radar, the latter also including the exploitation of cooperative and non-cooperative radar transmitters.
Space-time adaptive processing (STAP) is a signal processing technique most commonly used in radar systems. It involves adaptive array processing algorithms to aid in target detection. Radar signal processing benefits from STAP in areas where interference is a problem. Through careful application of STAP, it is possible to achieve order-of-magnitude sensitivity improvements in target detection.
The Russian BRLS-8B "Zaslon" (Barrier) is an all-weather multimode airborne radar developed between 1975 and 1980 by the Tikhomirov Scientific Research Institute of Instrument Design as part of the weapons control system of the MiG-31 supersonic interceptor. The NATO reporting name for the radar is Flash Dance with the designations "SBI-16", "RP-31", "N007" and "S-800" also being associated with the radar.
Moving target indication (MTI) is a mode of operation of a radar to discriminate a target against the clutter. It describes a variety of techniques used to find moving objects, like an aircraft, and filter out unmoving ones, like hills or trees. It contrasts with the modern stationary target indication (STI) technique, which uses details of the signal to directly determine the mechanical properties of the reflecting objects and thereby find targets whether they are moving or not.
The "Pegmantit 8" or P-8 was an early 2D VHF radar developed and operated by the former Soviet Union.
The P-12 "Yenisei" was an early VHF developed and operated by the former Soviet Union.
The P-18 or 1RL131Terek is a 2D VHF radar 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-40"Armour" or 1S12 is a 3-D UHF radar developed and operated by the former Soviet Union.
The P-70 or "Lena-M" was a static 2D VHF radar developed and operated by the former 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.
The P-30"Khrustal" also referred to by the NATO reporting name "Big Mesh" in the west is a 2D E band/F band radar developed and operated by the former Soviet Union.
The P-20"Periskop" also referred to by the NATO reporting name "Bar Lock" in the west is a 2D E band/F band radar developed and operated by the former Soviet Union.
The P-35 also referred to by the NATO reporting name "Bar Lock" in the west is a 2D E band/F band radar developed and operated by the former Soviet Union.
This is an overview of Russian early warning radars for air surveillance, and related design bureaus.