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Search And Rescue Transponder
A search and rescue transponder (SART) is a self-contained, waterproof transponder intended for emergency use at sea. These devices may be either a radar-SART, or a GPS-based AIS-SART (automatic identification system SART). The radar-SART is used to locate a survival craft or distressed vessel by creating a series of dots on a rescuing ship's radar display. A SART will only respond to a 9 GHz X-band (3 cm wavelength) radar. It will not be seen on S-band (10 cm) or other radar. Shipboard Global Maritime Distress Safety System (GMDSS) include one or more search and rescue locating devices. The radar-SART may be triggered by any X-band radar within a range of approximately . Each radar pulse received causes the SART to transmit a response which is swept repetitively across the complete radar frequency band. When interrogated, it first sweeps rapidly (0.4 microsecond) through the band before beginning a relatively slow sweep (7.5 microseconds) through the band back t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SART Radar Transponder
Sart is a name for the settled inhabitants of Central Asia which has had shifting meanings over the centuries. According to Great Soviet Encyclopedia, before the October Revolution of 1917, the name “Sart” was used in relation to the Uyghurs and Uzbeks by Kazakhs, Kyrgyz, and semi-nomadic Uzbeks. Origin There are several theories about the origin of the term. It may be derived from the Sanskrit ''sārthavāha'' ( सार्थवाह), meaning "merchant, trader, caravan leader", a term supposedly used by nomads to describe town-dwellers, according to Vasily Bartold, Gerard Clauson, and most recently Richard Foltz. The earliest known use of the term is in the 1070 Karakhanid Turkic text ''Kutadgu Bilig'' "Blessed Knowledge", in which it refers to the settled population of Kashgar. The term referred to all settled Muslims of Central Asia regardless of language. Rashid al-Din Hamadani in the ''Jami' al-tawarikh'' writes that Genghis Khan commande ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microsecond
A microsecond is a unit of time in the International System of Units (SI) equal to one millionth (0.000001 or 10−6 or ) of a second. Its symbol is μs, sometimes simplified to us when Unicode is not available. A microsecond is to one second, as one second is to approximately 11.57 days. A microsecond is equal to 1000 nanoseconds or of a millisecond. Because the next SI prefix is 1000 times larger, measurements of 10−5 and 10−4 seconds are typically expressed as tens or hundreds of microseconds. Examples * 1 microsecond (1 μs) – cycle time for frequency (1 MHz), the inverse unit. This corresponds to radio wavelength 300 m (AM medium wave band), as can be calculated by multiplying 1 μs by the speed of light (approximately ). * 1 microsecond – the length of time of a high-speed, commercial strobe light flash (see air-gap flash). * 1 microsecond – protein folding takes place on the order of microseconds (thus this is the speed of carbon-based ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emergency Communication
An emergency is an urgent, unexpected, and usually dangerous situation that poses an immediate risk to health, life, property, or environment and requires immediate action. Most emergencies require urgent intervention to prevent a worsening of the situation, although in some situations, mitigation may not be possible and agencies may only be able to offer palliative care for the aftermath. While some emergencies are self-evident (such as a natural disaster that threatens many lives), many smaller incidents require that an observer (or affected party) decide whether it qualifies as an emergency. The precise definition of an emergency, the agencies involved and the procedures used, vary by jurisdiction, and this is usually set by the government, whose agencies ( emergency services) are responsible for emergency planning and management. Defining an emergency An incident, to be an emergency, conforms to one or more of the following, if it: * Poses an immediate threat to life, h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maritime Communication
Maritime may refer to: Geography * Maritime Alps, a mountain range in the southwestern part of the Alps * Maritime Region, a region in Togo * Maritime Southeast Asia * The Maritimes, the Canadian provinces of Nova Scotia, New Brunswick, and Prince Edward Island * Maritime County, former county of Poland, existing from 1927 to 1939, and from 1945 to 1951 * Neustadt District, Reichsgau Danzig-West Prussia, known from 1939 to 1942 as ''Maritime District'', a former district of Reichsgau Danzig-West Prussia, Nazi Germany, from 1939 to 1945 * The Maritime Republics, thalassocratic city-states on the Italian peninsula during the Middle Ages Museums * Maritime museum (sometimes nautical museum), a museum for the display of objects relating to ships and travel on large bodies of water. * Maritime Museum (Belize) * Maritime Museum (Macau), China * Maritime Museum (Malaysia) * Maritime Museum (Stockholm), Sweden Music * ''Maritime'' (album), a 2005 album by Minotaur Shock * Maritime ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Maritime Organization
The International Maritime Organization (IMO; ; ) is a List of specialized agencies of the United Nations, specialized agency of the United Nations responsible for regulating maritime transport. The IMO was established following agreement at a UN conference held in Geneva in 1948 and the IMO came into existence ten years later, meeting for the first time on 17 March 1958. Headquartered in London, United Kingdom, the IMO, in 2024, has 176 Member States and three Associate Members. The IMO's primary purpose is to develop and maintain a comprehensive regulatory framework for shipping and its remit today includes maritime safety, environmental concerns, and Admiralty law, legal matters, among other issues. IMO is governed by an assembly of members which meets every two years. Its finance and organization is administered by a council of 40 members elected from the assembly. The work of IMO is conducted through five committees and these are supported by technical subcommittees. Other ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emergency Locator Beacon
An emergency locator beacon is a radio beacon, a portable battery powered radio transmitter, used to geolocalization, locate airplanes, vessels, and persons in distress and in need of immediate rescue. Various types of emergency locator beacons are carried by aircraft, ships, vehicles, hikers and cross-country skiers. In case of an emergency, such as the aircraft crashing, the ship sinking, or a hiker becoming lost, the transmitter is deployed and begins to transmit a continuous radio signal, which is used by search and rescue teams to quickly find the emergency and render aid. The purpose of all emergency locator beacons is to help rescuers find survivors within the so-called "golden day", the first 24 hours following a traumatic event, during which the majority of survivors can usually be saved. Beacon types COSPAS-SARSAT 406 MHz Distress Beacons International Cospas-Sarsat Programme, Cospas-Sarsat is an international humanitarian consortium of governmental and private ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Racon
Radar beacon (short: racon) is – according to ''article 1.103'' of the International Telecommunication Union's (ITU) ITU Radio Regulations (RR) – defined as "A transmitter-receiver associated with a fixed navigational mark which, when triggered by a radar, automatically returns a distinctive signal which can appear on the display of the triggering radar, providing range, bearing and identification information." Each ''station'' (transmitter-receiver, transceiver or transponder) shall be classified by the ''service'' in which it operates permanently or temporarily. Principle of operation When a racon receives a radar pulse, it responds with a signal on the same frequency which puts an image on the radar display. This takes the form of a short line of dots and dashes forming a Morse character radiating away from the location of the beacon on the normal plan position indicator radar display. The length of the line usually corresponds to the equivalent of a few nautical mile ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marine VHF Radio
Marine VHF radio is a worldwide system of two way radio transceivers on ships and watercraft used for bidirectional voice communication from ship-to-ship, ship-to-shore (for example with harbormasters), and in certain circumstances ship-to-aircraft. It uses FM channels in the very high frequency (VHF) radio band in the frequency range between 156 and 174 MHz, designated by the International Telecommunication Union as the ''VHF maritime mobile band''. In some countries additional channels are used, such as the L and F channels for leisure and fishing vessels in the Nordic countries (at 155.5–155.825 MHz). Transmitter power is limited to 25 watts, giving them a range of about . Marine VHF radio equipment is installed on all large ships and most seagoing small craft. It is also used, with slightly different regulation, on rivers and lakes. It is used for a wide variety of purposes, including marine navigation and traffic control, summoning rescue services and commun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emergency Position-indicating Radio Beacon
An emergency position-indicating radiobeacon (EPIRB) is a type of emergency locator beacon for commercial and recreational boats; it is a portable, battery-powered radio transmitter used in emergencies to locate boaters in distress and in need of immediate rescue. In the event of an emergency, such as a ship sinking or medical emergency onboard, the transmitter is activated and begins transmitting a continuous 406 MHz distress radio signal, which is used by search-and-rescue teams to quickly locate the emergency and render aid. The distress signal is detected by satellites operated by an international consortium of rescue services, COSPAS-SARSAT, which can detect emergency beacons anywhere on Earth transmitting on the distress frequency of 406 MHz. The satellites calculate the position or utilize the GPS coordinates of the beacon and quickly pass the information to the appropriate local first responder organization, which performs the search and rescue. As the sea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Civil Air Patrol
Civil Air Patrol (CAP) is a Congressional charter, congressionally chartered, federally supported Nonprofit corporation, non-profit corporation that serves as the official civilian auxiliaries, auxiliary of the United States Air Force (USAF). CAP is a volunteer organization with an aviation-minded membership that includes members from all backgrounds. The program is established as an organization by Title 10 of the United States Code and its purposes defined by Title 36 of the United States Code, Title 36. Membership in the organization consists of cadets ranging from 12 to just under 21 years of age, and senior members 18 years of age and up. These two groups each have the opportunity to participate in a wide variety of pursuits; the cadet program contributes to the development of the former group with a structured syllabus and an organization based upon United States Air Force ranks, while the older members serve as instructors, supervisors, and operators. Most members wear uni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Passband
A passband is the range of frequency, frequencies or wavelengths that can pass through a Filter (signal processing), filter. For example, a radio receiver contains a bandpass filter to select the frequency of the desired radio signal out of all the radio waves picked up by its antenna. The passband of a receiver is the range of frequencies it can receive when it is tuned into the desired frequency as in a radio station or television channel. A band-pass filter, bandpass-filtered signal (that is, a signal with energy only in a passband), is known as a bandpass signal, in contrast to a baseband signal. The bandpass filter usually has two stopband, band-stop filters. Filters In telecommunications, optics, and acoustics, a passband (a band-pass filtered signal) is the portion of the frequency spectrum that is transmitted (with minimum relative loss or maximum relative Gain (electronics), gain) by some filtering device. In other words, it is a ''band'' of frequencies which ''pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frequency
Frequency is the number of occurrences of a repeating event per unit of time. Frequency is an important parameter used in science and engineering to specify the rate of oscillatory and vibratory phenomena, such as mechanical vibrations, audio signals (sound), radio waves, and light. The interval of time between events is called the period. It is the reciprocal of the frequency. For example, if a heart beats at a frequency of 120 times per minute (2 hertz), its period is one half of a second. Special definitions of frequency are used in certain contexts, such as the angular frequency in rotational or cyclical properties, when the rate of angular progress is measured. Spatial frequency is defined for properties that vary or cccur repeatedly in geometry or space. The unit of measurement of frequency in the International System of Units (SI) is the hertz, having the symbol Hz. Definitions and units For cyclical phenomena such as oscillations, waves, or for examp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
