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P-18 Radar
The P-18 or 1RL131 Terek (also referred to by the NATO reporting name "Spoon Rest D" in the west) is a 2D VHF radar developed and operated by the former Soviet Union. Development The P-18 early warning radar is a development of the earlier P-12 radar, the P-18 radar being accepted into service in 1970 following the successful completion of the program. The P-18 was developed by the SKB Design Bureau, a division of State Plant No.197 named after V. I. Lenin who developed the previous P-12, the predecessor of the current Nizhny Novgorod Research Institute of Radio Engineering (NNIIRT). In 1979 a new secondary IFF radar the 1L22 "Parol" entered into service to complement the P-18, unlike the previous secondary radar NRS-12 (NATO "Score Board") the new interrogator was carried on a separate truck. The P-18 is still in service today and was widely exported, many companies offer upgrade options to improve the performance and reliability of the radar and to replace out-dated comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Warning Radar
An early-warning radar is any radar system used primarily for the long-range detection of its targets, i.e., allowing defences to be alerted as ''early'' as possible before the intruder reaches its target, giving the air defences the maximum time in which to operate. This contrasts with systems used primarily for tracking or gun laying, which tend to offer shorter ranges but offer much higher accuracy. EW radars tend to share a number of design features that improve their performance in the role. For instance, EW radar typically operates at lower frequencies, and thus longer wavelengths, than other types. This greatly reduces their interaction with rain and snow in the air, and therefore improves their performance in the long-range role where their coverage area will often include precipitation. This also has the side-effect of lowering their optical resolution, but this is not important in this role. Likewise, EW radars often use much lower pulse repetition frequency to maximiz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yagi Antenna
Yagi may refer to: Places *Yagi, Kyoto, in Japan * Yagi (Kashihara), in Nara Prefecture, Japan * Yagi Ridge, a mountain ridge in British Columbia, Canada * Yagi-nishiguchi Station, in Kashihara, Nara, Japan * Kami-Yagi Station, a JR-West Kabe Line station located in 3-chōme, Yagi, Asaminami-ku, Hiroshima, Hiroshima Prefecture, Japan * Rikutyū-Yagi Station, a railway station on the East Japan Railway Company Hachinohe Line located in Hirono, Iwate Prefecture, Japan * Yamato-Yagi Station, a Kintetsu Corporation railway train station situated in the Nara Prefecture Other uses * Yagi (surname) * Typhoon Yagi (other) * Yagi (''Usagi Yojimbo''), a comic book character *Yagi–Uda antenna A Yagi–Uda antenna, or simply Yagi antenna, is a directional antenna consisting of two or more parallel Antenna (radio)#Resonant antennas, resonant antenna elements in an Antenna array#Types, end-fire array; these elements are most often metal ..., a directional radio antenna * Yagibushi< ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anti-aircraft Warfare
Anti-aircraft warfare (AAW) is the counter to aerial warfare and includes "all measures designed to nullify or reduce the effectiveness of hostile air action".AAP-6 It encompasses surface-based, subsurface (Submarine#Armament, submarine-launched), and air-based weapon systems, in addition to associated sensor systems, command and control arrangements, and passive measures (e.g. barrage balloons). It may be used to protect naval, army, ground, and air forces in any location. However, for most countries, the main effort has tended to be homeland defense. Missile defense, Missile defense is an extension of air defence, as are initiatives to adapt air defence to the task of intercepting any projectile in flight. Most modern anti-aircraft (AA) weapons systems are optimized for short-, medium-, or long-range air defence, although some systems may incorporate multiple weapons (such as both autocannons and surface-to-air missiles). 'Layered air defence' usually refers to multiple 't ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Path Loss
Path loss, or path attenuation, is the reduction in power density (attenuation) of an electromagnetic wave as it propagates through space. Path loss is a major component in the analysis and design of the link budget of a telecommunication system. This term is commonly used in wireless communications and signal propagation. Path loss may be due to many effects, such as free-space loss, refraction, diffraction, reflection, aperture- medium coupling loss, and absorption. Path loss is also influenced by terrain contours, environment (urban or rural, vegetation and foliage), propagation medium (dry or moist air), the distance between the transmitter and the receiver, and the height and location of antennas. Overview In wireless communications, path loss is the reduction in signal strength as the signal travels from a transmitter to a receiver, and is an application for verifying the loss. There are several factors that affect this: *Free-space path loss: This is the fundame ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anti-radiation Missile
An anti-radiation missile (ARM) is a missile designed to detect and home in on an enemy radio emission source. Typically, these are designed for use against an enemy radar, although jammers and even radios used for communications can also be targeted in this manner. The earliest known anti-radiation weapon is a variant of the Blohm & Voss BV 246 radar guided bomb.Lepage, Jean-Denis G.G. (2009). Aircraft of the Luftwaffe 1935-1945. McFarland. p. 67. . Home-on-jam As jammers proliferated, a number of existing ARMs such as the AGM-88 HARM was modified to also target jammers as the source of radiation. Jammers also led to the addition of a feature to missiles that usually use a different targeting mode (e.g. active radar homing, semi-active radar homing, GPS), allowing them to switch to an anti-radiation targeting mode when radar deteriorates too much. Some examples are: * JDAM and JDAM-ER, air-to-surface GPS bomb * AMRAAM, active radar homing air-to-air missile * R-77, active ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radar Jamming And Deception
Radar jamming and deception is a form of electronic countermeasures (ECMs) that intentionally sends out radio frequency signals to interfere with the operation of radar by saturating its receiver with noise or false information. Concepts that blanket the radar with signals so its display cannot be read are normally known as jamming, while systems that produce confusing or contradictory signals are known as deception, but it is also common for all such systems to be referred to as jamming. There are two general classes of radar jamming, mechanical and electronic. Mechanical jamming entails reflecting enemy radio signals in various ways to provide false or misleading target signals to the radar operator. Electronic jamming works by transmitting additional radio signals towards enemy receivers, making it difficult to detect real target signals, or take advantage of known behaviors of automated systems like radar lock-on to confuse the system. Various Electronic counter-countermeasur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electronic Counter-countermeasure
Electronic counter-countermeasures (ECCM) is a part of electronic warfare which includes a variety of practices which attempt to reduce or eliminate the effect of electronic countermeasures (ECM) on electronic sensors aboard vehicles, ships and aircraft and weapons such as missiles. ECCM is also known as electronic protective measures (EPM), chiefly in Europe. In practice, EPM often means resistance to jamming. A more detailed description defines it as the electronic warfare operations taken by a radar to offset the enemy's countermeasure. History Ever since electronics have been used in battle in an attempt to gain superiority over the enemy, effort has been spent on techniques to reduce the effectiveness of those electronics. More recently, sensors and weapons are being modified to deal with this threat. One of the most common types of ECM is radar jamming or spoofing. This originated with the Royal Air Force's use of what they codenamed ''Window'' during World War II, whi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nebo-SVU
The Nebo-SVU (also known as 1L119) (in Cyrillic: Небо-СВУ, 1Л119) is a very high frequency (VHF) multi-functional radar and the first radar with an active electronically scanned array (AESA) antenna operating at meter wavelengths. The radar was introduced in 2001 as a replacement for the Nebo-SV. It can locate aircraft and other flying objects with (1sqf) radar cross-section at a distance of . History VHF radar systems have wavelengths comparable to aircraft feature sizes and should exhibit scattering in the resonance region rather than the optical region, allowing most stealth aircraft to be detected. The Soviet Union was known for developing VHF radars such as the P-12 and P-18 radars with counter-stealth capabilities. A request to detect stealthy aircraft and provide anti-aircraft systems with their coordinates prompted the Nizhny Novgorod Research Institute of Radio Engineering (NNIIRT) to develop the VHF AESA Nebo-SVU radar with digital signal processors, which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stealth Technology
Stealth technology, also termed low observable technology (LO technology), is a sub-discipline of military tactics and passive and active electronic countermeasures. The term covers a range of military technology, methods used to make personnel, Stealth aircraft, aircraft, Stealth ship, ships, submarines, missiles, satellites, and Stealth ground vehicle, ground vehicles less visible (ideally invisible) to radar, Thermographic camera, infrared, sonar and other detection methods. It corresponds to military camouflage for these parts of the electromagnetic spectrum (i.e., multi-spectral camouflage). Development of modern stealth technologies in the United States began in 1958, where earlier attempts to prevent radar tracking of its Lockheed U-2, U-2 spy planes during the Cold War by the Soviet Union had been unsuccessful. Designers turned to developing a specific shape for planes that tended to reduce detection by redirecting electromagnetic radiation waves from radars. Radiation-a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Active Electronically Scanned Array
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). The AESA is a more advanced, sophisticated, second-generation of the original PESA phased-array technology. PESAs can only emit a single beam of radio waves at a single frequency at a time. The PESA must utilize a Butler matri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early-warning Radar
An early-warning radar is any radar system used primarily for the long-range detection of its targets, i.e., allowing defences to be alerted as ''early'' as possible before the intruder reaches its target, giving the air defences the maximum time in which to operate. This contrasts with systems used primarily for tracking or gun laying, which tend to offer shorter ranges but offer much higher accuracy. EW radars tend to share a number of design features that improve their performance in the role. For instance, EW radar typically operates at lower frequencies, and thus longer wavelengths, than other types. This greatly reduces their interaction with rain and snow in the air, and therefore improves their performance in the long-range role where their coverage area will often include precipitation. This also has the side-effect of lowering their optical resolution, but this is not important in this role. Likewise, EW radars often use much lower pulse repetition frequency to maximi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
