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Track-via-missile
Track-via-missile or TVM refers to a missile guidance technique which combines features of semi-active radar homing (SARH) and radio command guidance. This avoids the problems with terminal accuracy normally seen by command guided missiles, especially at long range. It has been used on a number of long-range surface-to-air missiles (SAMs) including the MIM-104 Patriot. Explanation Command guidance has the advantage of isolating most of the equipment for the missile guidance at the launcher, where size and weight are significantly less important. In these systems, the radar that provides guidance is on the ground or ship and the missile lacks an independent guidance system. Typically two radars are used, one tracking the target and another the missile, so that they can fly independent and widely separated paths. A computer then calculates the position and velocity of the two and calculates an intercept point. The same computer then calculates the control inputs needed to fly the m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MIM-104 Patriot
The MIM-104 Patriot is a mobile interceptor missile surface-to-air missile (SAM) system, the primary such system used by the United States Army and several allied states. It is manufactured by the U.S. defense contractor Raytheon and derives its name from the radar component of the weapon system. The AN/MPQ-53 at the heart of the system is known as the "Phased Array Tracking Radar to Intercept on Target", which is a backronym for "Patriot". In 1984, the Patriot system began to replace the Nike Hercules system as the U.S. Army's primary high to medium air defense (HIMAD) system and the MIM-23 Hawk system as the U.S. Army's medium tactical air defense system. In addition to these roles, Patriot has been given a function in the U.S. Army's anti-ballistic missile (ABM) system. , the system is expected to stay fielded until at least 2040. Patriot uses an advanced aerial interceptor missile and high-performance radar systems. Patriot was developed at Redstone Arsenal in Huntsville, A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Missile Guidance
Missile guidance refers to a variety of methods of guiding a missile or a guided bomb to its intended target. The missile's target accuracy is a critical factor for its effectiveness. Guidance systems improve missile accuracy by improving its Probability of Guidance (Pg). These guidance technologies can generally be divided up into a number of categories, with the broadest categories being "active", "passive", and "preset" guidance. Missiles and guided bombs generally use similar types of guidance system, the difference between the two being that missiles are powered by an onboard engine, whereas guided bombs rely on the speed and height of the launch aircraft for propulsion. History The concept of unmanned guidance originated at least as early as World War I, with the idea of remotely guiding an airplane bomb onto a target, such as the systems developed for the R.F.C. World War I Drone Weapons, first powered drones by Archibald Low (the father of radio guidance). In World War ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Active Radar Homing
Active radar homing (ARH) is a missile guidance method in which a missile contains a radar transceiver (in contrast to semi-active radar homing, which uses only a passive radar, receiver) and the electronics necessary for it to find and track its target autonomously. The NATO brevity code for an air-to-air active radar homing missile launch is fox (code word), Fox Three. Advantages There are two major advantages to active radar homing: * As the missile is tracking the target it is going to be much closer to the target than the launching platform during the terminal phase, thus the missile's tracking can be much more accurate and better resistant to electronic countermeasures. Active radar homing missiles have some of the best kill probability, kill probabilities, along with missiles employing track-via-missile guidance. * Because the missile is totally autonomous during the terminal phase, the launch platform does not need to have its radar enabled at all during this phase, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AN/SPG-59
The AN/SPG-59 was an advanced PESA phased array radar developed by the U.S. Navy starting in 1958. It was one of the earliest phased array radars. AN/SPG-59 was intended to offer search, track and guidance from a single radar system and antenna as part of the Typhon combat system. Paired with the new Typhon missile, the system was to provide wide-area air defense out to about from suitable anti-aircraft cruisers. Both the radar and missile proved to be well beyond the state of the art of the era, and the project was eventually canceled in December 1963.Dranidis, Dimitris V. Shipboard Phased-Array Radars''. Waypoint Magazine. February 2003. (Written to support wargames, but informative.) In accordance with the Joint Electronics Type Designation System (JETDS), the "''AN/SPG-59''" designation represents the 59th design of an Army-Navy electronic device for waterborne fire control radar system. The JETDS system also now is used to name all Department of Defense electronic syste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HQ-9
The HQ-9 ( zh, s=红旗-9, t=紅旗-9, p=Hóng Qí-9, l=Red Banner-9; NATO reporting name: CH-SA-9.) is a long-range semi-active radar homing (SARH) surface-to-air missile (SAM) developed by the People's Republic of China. The naval variant is the HHQ-9 ( zh, s=海红旗-9, t=海紅旗-9, p=Hǎi Hóng Qí-9, l=Sea Red Banner-9). Description The HQ-9 is a derivative of the Russian S-300. Justin Bronk of the Royal United Services Institute describes the missile as a "hybrid design based on the Russian SA-20 but with radar, seeker head and C2 elements heavily influenced by American and Israeli technology." The missile uses track-via-missile (TVM) guidance combining inertial guidance, mid-course uplink, and terminal active radar. The TVM used on earlier missiles may have been developed from a United States MIM-104 Patriot missile purchased from Israel or Germany. According to a 2001 article from ''Defence International'', the HQ-9 is 6.8 m. long with a mass of nearly two tons. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Command Guidance
Command guidance is a type of missile guidance in which a ground station or aircraft relay signals to a guided missile via radio control or through a wire connecting the missile to the launcher and tell the missile where to steer to intercept its target. This control may also command the missile to detonate, even if the missile has a fuze. Typically, the system giving the guidance commands is tracking both the target and the missile or missiles via radar. It determines the positions and velocities of a target and a missile, and calculates whether their paths will intersect. If not, the guidance system will relay commands to a missile, telling it to move the fins in a way that steers in the direction needed to maneuver to an intercept course with the target. If the target maneuvers, the guidance system can sense this and update the missiles' course continuously to counteract such maneuvering. If the missile passes close to the target, either its own proximity or contact fuze wil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Passive Electronically Scanned Array
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 (that is, a phased array antenna), in which all the antenna elements are connected to a single transmitter (such as a magnetron, a klystron or a travelling wave tube) 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. A PESA contrasts with an active electronically scanned array (AESA) antenna, which has a separate transmitter and/or receiver unit for each antenna element, all controlled by a computer; AESA is a more advanced, sophisticated versatile second-generation version of the original PESA phased array technology. Hybrids of the two can also be found, consisting of subarrays that individually resemble PESAs, where each subarray has its own RF front e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anti-radiation Missiles
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] |
Fire And Forget
Fire-and-forget is a type of missile guidance which does not require further external intervention after launch such as illumination of the target or wire guidance, and can hit its target without the launcher being in line-of-sight of the target. This is an important property for a guided weapon to have, since a person or vehicle that lingers near the target to guide the missile (using, for instance, a laser designator) is vulnerable to attack and unable to carry out other tasks. Generally, information about the target is programmed into the missile just prior to launch. This can include coordinates, radar measurements (including velocity), or an infrared image of the target. After it is fired, the missile guides itself by some combination of gyroscopes and accelerometers, GPS, onboard active radar homing, infrared homing optics, and anti-radiation homing. Some systems offer the option of either continued input from the launch platform or fire-and-forget. Fire-and-forget m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electronic Countermeasures
An electronic countermeasure (ECM) is an electrical or electronic device designed to countermeasure, trick or deceive radar, sonar, or other detection systems, like infrared (IR) or lasers. It may be used both offensively and defensively to deny targeting information to an enemy. The system may make many separate targets appear to the enemy, or make the real target appear to disappear or move about randomly. It is used effectively to protect aircraft from guided missiles. Most air forces use ECM to protect their aircraft from attack. It has also been deployed by military ships and recently on some advanced tanks to fool laser/IR guided missiles. It is frequently coupled with stealth advances so that the ECM systems have an easier job. Offensive ECM often takes the form of Radar jamming, jamming. Self-protecting (defensive) ECM includes using blip enhancement and jamming of missile guidance, missile terminal homers. History The first example of electronic countermeasures being a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spoofing Attack
In the context of information security, and especially network security, a spoofing attack is a situation in which a person or program successfully identifies as another by falsifying data, to gain an illegitimate advantage. Internet Spoofing and TCP/IP Many of the protocols in the TCP/IP suite do not provide mechanisms for authenticating the source or destination of a message, leaving them vulnerable to spoofing attacks when extra precautions are not taken by applications to verify the identity of the sending or receiving host. IP spoofing and ARP spoofing in particular may be used to leverage man-in-the-middle attacks against hosts on a computer network. Spoofing attacks which take advantage of TCP/IP suite protocols may be mitigated with the use of firewalls capable of deep packet inspection or by taking measures to verify the identity of the sender or recipient of a message. Domain name spoofing The term 'Domain name spoofing' (or simply though less accurately, 'Domain ... [...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] |
