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Enhanced RADAR Positioning
Enhanced radar positioning is a proposal for a position fixing system in maritime navigation, based on radar navigation. It is the automation of the process of determining own position by means of radar fixing, using a multitude of objects with known position as reference. The proposal was originally made by Jens K. Jensen from the Danish Maritime Safety Administration in 2009, in relation to the need for an independent source for position fixing, due to the vulnerabilities of GPS and other satellite navigation systems, identified during the work at IALA on IMO's e-Navigation strategy. This proposal is currently being brought forward to the maritime industry through IALA, and an opportunity for practical testing of the concept in 2011 is being considered in the EfficienSea project partly financed by the Baltic Sea Region Programme and coordinated by the Danish Maritime Safety Administration. Principle The navigation radar of a ship is currently considered a primary position ver ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Position Fixing
Geopositioning, also known as geotracking, geolocalization, geolocating, geolocation, or geoposition fixing, is the process of determining or estimating the geographic position of an object. Geopositioning yields a set of geographic coordinates (such as latitude and longitude) in a given map datum; positions may also be expressed as a bearing and range from a known landmark. In turn, positions can determine a meaningful location, such as a street address. Specific instances include: animal geotracking, the process of inferring the location of animals; positioning system, the mechanisms for the determination of geographic positions in general; internet geolocation, geolocating a device connected to the internet; and mobile phone tracking. Background Geopositioning uses various visual and electronic methods including position lines and position circles, celestial navigation, radio navigation, and the use of satellite navigation systems. The calculation requires measurements or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Navigation
Navigation is a field of study that focuses on the process of monitoring and controlling the movement of a craft or vehicle from one place to another.Bowditch, 2003:799. The field of navigation includes four general categories: land navigation, marine navigation, aeronautic navigation, and space navigation. It is also the term of art used for the specialized knowledge used by navigators to perform navigation tasks. All navigational techniques involve locating the navigator's position compared to known locations or patterns. Navigation, in a broader sense, can refer to any skill or study that involves the determination of position and direction. In this sense, navigation includes orienteering and pedestrian navigation. History In the European medieval period, navigation was considered part of the set of '' seven mechanical arts'', none of which were used for long voyages across open ocean. Polynesian navigation is probably the earliest form of open-ocean navigation; it was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radar Navigation
Radar navigation is the utilization of marine and aviation radar systems for vessel and aircraft navigation. When a craft is within radar range of land or special radar aids to navigation, the navigator can take distances and angular bearings to charted objects and use these to establish arcs of position and lines of position on a chart.Maloney, 2003:744. A fix consisting of only radar information is called a ''radar fix''.Bowditch, 2002:816. Some types of radar fixes include the relatively self-explanatory methods of "range and bearing to a single object,"National Imagery and Mapping Agency, 2001:163. "two or more bearings," "tangent bearings," and "two or more ranges." Parallel indexing is a technique defined by William Burger in the 1957 book ''The Radar Observer's Handbook''.National Imagery and Mapping Agency, 2001:169. This technique involves creating a line on the screen that is parallel to the ship's course, but offset to the left or right by some distance. This p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radar
Radar is a detection system that uses radio waves to determine the distance (''ranging''), angle, and radial velocity of objects relative to the site. 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 (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 information about the objects' locations and speeds. Radar was developed secretly for military use by several countries in the period before and during World War II. A key development was the cavity magnetron in the United Kingdom, which allowed the creation of relatively small systems with sub-meter resolution. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Danish Maritime Safety Administration
The Danish Maritime Safety Administration (DaMSA) ( da, Farvandsvæsenet) was a department of the Danish Ministry of Defence with administration located in Christianshavn, Copenhagen. DaMSA operated throughout Denmark as part of the Danish Search and Rescue (SAR) organization that runs 21 rescue stations located along the coasts of Denmark. Responsibilities of DaMSA included authorizing navigation systems and buoyage, resolving issues concerning wrecks and their salvage in Danish waters, and running the Danish Pilotage Service (Lodsvæsenet). DaMSA was the Centre for Operational Oceanography, which collects hydrographical and oceanographic data from all national waters, and makes charts and maps for use by the Military of Denmark and civilians. DaMSA was a full member of the North West Shelf Operational Oceanographic System. History On 1 April 1973 ''Farvandsdirektoratet'' was established by merging the following organizations: Danish Lighthouse Service (Fyrvæsenet), Dani ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Satellite Navigation
A satellite navigation or satnav system is a system that uses satellites to provide autonomous geo-spatial positioning. It allows satellite navigation devices to determine their location (longitude, latitude, and altitude/elevation) to high precision (within a few centimetres to metres) using time signals transmitted along a line of sight by radio from satellites. The system can be used for providing position, navigation or for tracking the position of something fitted with a receiver (satellite tracking). The signals also allow the electronic receiver to calculate the current local time to a high precision, which allows time synchronisation. These uses are collectively known as Positioning, Navigation and Timing (PNT). One set of critical vulnerabilities in satellite communications are the signals that govern positioning, navigation and timing (PNT). Failure to properly secure these transmissions could not only disrupt satellite networks but wreak havoc on a host of dependent s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
