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Tamara Passive Sensor
Tamara was the third generation Czechoslovak electronic support measures ( ESM) system that used measurements of time difference of arrival (TDOA) of pulses at three or four sites to accurately detect and track airborne emitters by multilateration. Tamara's designations were KRTP-86 and KRTP-91 and it carried the NATO reporting name of Trash Can. The designation was derived from the Czech phrase "Komplet Radiotechnického Průzkumu" meaning "Radiotechnical Reconnaissance Set". It was claimed to be the only one in the world able to detect military " invisible aircraft". History Development of Tamara by the state-run company Tesla in Pardubice began in 1981 and continued until 1983. Tests of a mobile system began in September 1984 through to 1985. It was finally deployed in 1987 following acceptance tests in October of that year. In 1991 the baseline KRTP-86 Tamara was superseded in production by the improved KRTP-91 Tamara-M. Appearance Unlike its predecessors, Tamara was a mob ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Czechoslovakia
Czechoslovakia ( ; Czech language, Czech and , ''Česko-Slovensko'') was a landlocked country in Central Europe, created in 1918, when it declared its independence from Austria-Hungary. In 1938, after the Munich Agreement, the Sudetenland became part of Nazi Germany, while the country lost further territories to First Vienna Award, Hungary and Trans-Olza, Poland (the territories of southern Slovakia with a predominantly Hungarian population to Hungary and Zaolzie with a predominantly Polish population to Poland). Between 1939 and 1945, the state ceased to exist, as Slovak state, Slovakia proclaimed its independence and Carpathian Ruthenia became part of Kingdom of Hungary (1920–1946), Hungary, while the German Protectorate of Bohemia and Moravia was proclaimed in the remainder of the Czech Lands. In 1939, after the outbreak of World War II, former Czechoslovak President Edvard Beneš formed Czechoslovak government-in-exile, a government-in-exile and sought recognition from the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Hyperboloid
In geometry, a hyperboloid of revolution, sometimes called a circular hyperboloid, is the surface generated by rotating a hyperbola around one of its principal axes. A hyperboloid is the surface obtained from a hyperboloid of revolution by deforming it by means of directional scalings, or more generally, of an affine transformation. A hyperboloid is a quadric surface, that is, a surface defined as the zero set of a polynomial of degree two in three variables. Among quadric surfaces, a hyperboloid is characterized by not being a cone or a cylinder, having a center of symmetry, and intersecting many planes into hyperbolas. A hyperboloid has three pairwise perpendicular axes of symmetry, and three pairwise perpendicular planes of symmetry. Given a hyperboloid, one can choose a Cartesian coordinate system such that the hyperboloid is defined by one of the following equations: + - = 1, or + - = -1. The coordinate axes are axes of symmetry of the hyperboloid and th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
ELINT
Signals intelligence (SIGINT) is the act and field of intelligence-gathering by interception of ''signals'', whether communications between people (communications intelligence—abbreviated to COMINT) or from electronic signals not directly used in communication (electronic intelligence—abbreviated to ELINT). As classified and sensitive information is usually encrypted, signals intelligence may necessarily involve cryptanalysis (to decipher the messages). Traffic analysis—the study of who is signaling to whom and in what quantity—is also used to integrate information, and it may complement cryptanalysis. History Origins Electronic interceptions appeared as early as 1900, during the Boer War of 1899–1902. The British Royal Navy had installed wireless sets produced by Marconi on board their ships in the late 1890s, and the British Army used some limited wireless signalling. The Boers captured some wireless sets and used them to make vital transmissions. Since the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
VERA Passive Sensor
The VERA passive radar, passive surveillance ESM system (known as ''Věra'' in Czech language, Czech) is an electronic support measures (ESM) system that uses measurements of time difference of arrival (TDOA) of pulses at three or four sites to accurately detect and track airborne emitters. The manufacturer is , based in Pardubice. History VERA is the latest in a long history of Czech ESM TDOA systems. The first system developed by the Czech army in 1963 was known as PRP-1 Kopáč passive sensor, Kopáč which could track 6 targets. This was followed by KRTP-81 Ramona passive sensor, Ramona (NATO reporting name Soft Ball) in 1979, which could track 20 targets, and KRTP-86 Tamara passive sensor, Tamara (NATO reporting name Trash Can) in 1987, which could simultaneously track 23 radar targets and 48 IFF targets. These were widely exported to the former Soviet Union and beyond. These predecessors were manufactured by the state company Tesla (Czechoslovak company), Tesla, which coll ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Ramona Passive Sensor
Ramona was the second generation Czechoslovak electronic support measures ( ESM) system that uses measurements of time difference of arrival (TDOA) of pulses at three or four sites to accurately detect and track airborne emitters by multilateration. History Ramona's designation was KRTP-81 and it carried the NATO reporting name of Soft Ball. The serial number was derived from the Czech phrase "''Komplet radiotechnického průzkumu''" meaning "Radiotechnical Reconnaissance Set". A later upgraded version was designated KRTP-81M. Ramona was deployed in 1979 and could semi-automatically track 20 targets simultaneously. It superseded Kopáč. Appearance Each receiver comprised a large spherical radome mounted on the top of a 25 m fixed mast. This radome, made of identical segments of polyurethane foam, contained the radio antennas and the microwave components, intermediate frequency preamplifiers and the two-way communications equipment for communicating between central and side sit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Kopáč Passive Sensor
Kopáč (the word means "''digger''" in Czech) was an early electronic warfare support measures (ESM) system developed in Czechoslovakia in the early 1960s that used measurements of time difference of arrival (TDOA) of pulses at three sites to accurately detect and track airborne emitters. The system used the principle of multilateration and was capable of simultaneously manually tracking up to six targets. It was first deployed in 1963 and was also known by its serial number, PRP-1. The initials PRP come from the Czech "Přesný radiotechnický pátrač", meaning "Accurate Radiotechnical Locator", the name comes from "Korelační pátrač", meaning "Correlation Locator". The concept was derived by Vlastimil Pech and patented in Czechoslovak classified patent 771 on November 13, 1961. Subsequent related patents 830, 852 and 859 were filed by Vladimír Zárybnický in 1962. The system used analogue signal processing and operated in D, G/ H and I/ J bands, as well as specific ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
East Germany
East Germany, officially known as the German Democratic Republic (GDR), was a country in Central Europe from Foundation of East Germany, its formation on 7 October 1949 until German reunification, its reunification with West Germany (FRG) on 3 October 1990. Until 1989, it was generally viewed as a communist state and described itself as a Socialist state, socialist "workers' and peasants' state". The Economy of East Germany, economy of the country was Central planning, centrally planned and government-owned corporation, state-owned. Although the GDR had to pay substantial war reparations to the Soviets, its economy became the most successful in the Eastern Bloc. Before its establishment, the country's territory was administered and occupied by Soviet forces following the Berlin Declaration (1945), Berlin Declaration abolishing German sovereignty in World War II. The Potsdam Agreement established the Soviet occupation zone in Germany, Soviet-occupied zone, bounded on the east b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Soviet Union
The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet Union, it dissolved in 1991. During its existence, it was the list of countries and dependencies by area, largest country by area, extending across Time in Russia, eleven time zones and sharing Geography of the Soviet Union#Borders and neighbors, borders with twelve countries, and the List of countries and dependencies by population, third-most populous country. An overall successor to the Russian Empire, it was nominally organized as a federal union of Republics of the Soviet Union, national republics, the largest and most populous of which was the Russian SFSR. In practice, Government of the Soviet Union, its government and Economy of the Soviet Union, economy were Soviet-type economic planning, highly centralized. As a one-party state go ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Radio Horizon
Line-of-sight propagation is a characteristic of electromagnetic radiation or acoustic wave propagation which means waves can only travel in a direct visual path from the source to the receiver without obstacles. Electromagnetic transmission includes light emissions traveling in a straight line. The rays or waves may be diffracted, refracted, reflected, or absorbed by the atmosphere and obstructions with material and generally cannot travel over the horizon or behind obstacles. In contrast to line-of-sight propagation, at low frequency (below approximately 3 MHz) due to diffraction, radio waves can travel as ground waves, which follow the contour of the Earth. This enables AM radio stations to transmit beyond the horizon. Additionally, frequencies in the shortwave bands between approximately 1 and 30 MHz, can be refracted back to Earth by the ionosphere, called skywave or "skip" propagation, thus giving radio transmissions in this range a potentially global reach. Howe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Identification Friend Or Foe
Identification, friend or foe (IFF) is a combat identification system designed for command and control. It uses a transponder that listens for an ''interrogation'' signal and then sends a ''response'' that identifies the broadcaster. IFF systems usually use radar frequencies, but other electromagnetic frequencies, radio or infrared, may be used. It enables military and civilian air traffic control interrogation systems to identify aircraft, vehicles or forces as friendly, as opposed to neutral or hostile, and to determine their bearing and range from the interrogator. IFF is used by both military and civilian aircraft. IFF was first developed during World War II, with the arrival of radar, and several friendly fire incidents. IFF can only positively identify friendly aircraft or other forces. If an IFF interrogation receives no reply or an invalid reply, the object is not positively identified as foe; friendly forces may not properly reply to IFF for various reasons such as e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Radar
Radar is a system that uses radio waves to determine the distance ('' ranging''), direction ( azimuth and elevation angles), and radial velocity of objects relative to the site. It is a radiodetermination method used to detect and track aircraft, ships, spacecraft, guided missiles, motor vehicles, map weather formations, and terrain. The term ''RADAR'' was coined in 1940 by the United States Navy as an acronym for "radio detection and ranging". The term ''radar'' has since entered English and other languages as an anacronym, a common noun, losing all capitalization. A radar system consists of a transmitter producing electromagnetic waves in the radio or microwave domain, a transmitting antenna, a receiving antenna (often the same antenna is used for transmitting and receiving) and a receiver and processor to determine properties of the objects. Radio waves (pulsed or continuous) from the transmitter reflect off the objects and return to the receiver, giving ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Propagation Delay
Propagation delay is the time duration taken for a signal to reach its destination, for example in the electromagnetic field, a wire, speed of sound, gas, fluid or seismic wave, solid body. Physics * An electromagnetic wave travelling through a medium has a propagation delay determined by the speed of light in that particular medium, or ca. 1 nanosecond per in a vacuum. * An electric signal travelling through a wire has an propagation delay of ca. 1 nanosecond per . See also radio propagation, velocity factor, signal velocity and mechanical wave. Electronics Logic gates can have a gate delay ranging from picoseconds to more than 10 nanoseconds, depending on the technology being used. It is the time between the gate input becoming stable and the gate output becoming stable. Manufacturers often refer to the time from the input changing to 50% of its final input level, to the output reaching 50% of its final output level; this may depend on the direction of the level cha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
