|
Communications, Navigation And Surveillance
Communication, navigation and surveillance (CNS) are the main functions that form the infrastructure for air traffic management, and ensure that air traffic is safe and efficient. Functions The CNS has the following three main functions. Communication Communication, i.e. aviation communication, refers to communication between two or more aircraft, the exchange of data or verbal information between aircraft and air traffic control and the ground based communication infrastructure of the ATM network (like the aeronautical fixed service). For continental airspace, VHF (civil) and UHF (military) systems are used whereas for oceanic areas, high frequency systems and SATCOMs are used. Navigation Navigation, i.e. air navigation, refers to the process of planning, recording, and controlling the movement of an aircraft from one place to another by providing accurate, reliable and seamless position determination capability. Surveillance Surveillance systems are used by air traffic co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Air Traffic Management
file:ATMANS.png, 334x334px, Air traffic management (ATM) aims at ensuring the safe and efficient flow of air traffic. It encompasses three types of services: * air traffic services (ATS) including air traffic control (ATC), air traffic advisory services, flight information services and alerting services, * airspace management (ASM), the purpose of which is to allocate Airway (aviation), air routes, zones, flight levels to different airspace users and the airspace structure, and * air traffic flow and capacity management (ATFCM) (or Air Traffic Flow Management, ATFM) consisting in regulating the flow of aircraft as efficiently as possible in order to avoid congestion in airspace and airports. The Convention on International Civil Aviation, Chicago Convention 1944 (52 signatory states) required each state to provide air navigation services for their own state and early air navigation service providers (ANSPs) were state-controlled monopolies. En-route navigation is still offered by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Communications Satellite
A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a Transponder (satellite communications), transponder; it creates a communication channel between a source transmitter and a Radio receiver, receiver at different locations on Earth. Communications satellites are used for television, telephone, radio, internet, and military applications. Many communications satellites are in geostationary orbit above the equator, so that the satellite appears stationary at the same point in the sky; therefore the satellite dish antennas of ground stations can be aimed permanently at that spot and do not have to move to track the satellite. Others form satellite constellations in low Earth orbit, where antennas on the ground have to follow the position of the satellites and switch between satellites frequently. The radio waves used for telecommunications links travel by Line-of-sight propagation, line of sight and so are obstructe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Primary Surveillance Radar
This is a list of different types of radar. Detection and search radars Search radars scan great volumes of space with pulses of short radio waves. They typically scan the volume two to four times a minute. The radio waves are usually less than a meter long. Ships and planes are metal, and reflect radio waves. The radar measures the distance to the reflector by measuring the time of the round trip from emission of a pulse to reception, dividing this by two, and then multiplying by the speed of light. To be accepted, the received pulse has to lie within a period of time called the ''range gate''. The radar determines the direction because the short radio waves behave like a search light when emitted from the reflector of the radar set's antenna. Search * Early Warning (EW) Radar Radar Systems ** Ground Control Intercept (GCI) Radar ** Airborne Early Warning (AEW) ** Airborne ground surveillance (AGS) ** Over-the-Horizon (OTH) Radar *Target Acquisition (TA, TAR) Radar Systems ** ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GNSS
A satellite navigation or satnav system is a system that uses satellites to provide autonomous geopositioning. A satellite navigation system with global coverage is termed global navigation satellite system (GNSS). , four global systems are operational: the United States's Global Positioning System (GPS), Russia's Global Navigation Satellite System (GLONASS), China's BeiDou Navigation Satellite System (BDS), and the European Union's Galileo. Two regional systems are operational: India's NavIC and Japan's QZSS. ''Satellite-based augmentation systems'' (SBAS), designed to enhance the accuracy of GNSS, include Japan's Quasi-Zenith Satellite System (QZSS), India's GAGAN and the European EGNOS, all of them based on GPS. Previous iterations of the BeiDou navigation system and the present Indian Regional Navigation Satellite System (IRNSS), operationally known as NavIC, are examples of stand-alone operating regional navigation satellite systems (RNSS). Satellite navigation devic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transponder (aeronautics)
A transponder (short for ''trans''mitter-res''ponder'' and sometimes abbreviated to XPDR, XPNDR, TPDR or TP) is an electronic device that produces a response when it receives a radio-frequency interrogation. Aircraft have transponders to assist in identifying them on air traffic control radar. Collision avoidance systems have been developed to use transponder transmissions as a means of detecting aircraft at risk of colliding with each other. Air traffic control (ATC) units use the term "squawk" when they are assigning an aircraft a transponder code, e.g., "Squawk 7421". Squawk thus can be said to mean "select transponder code" or "squawking ''xxxx''" to mean "I have selected transponder code ''xxxx''". The transponder receives interrogation from the secondary surveillance radar on 1030 MHz and replies on 1090 MHz. Secondary surveillance radar Secondary surveillance radar (SSR) is referred to as "secondary", to distinguish it from the "primary radar" that works ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Secondary Surveillance Radar
Secondary surveillance radar (SSR)''Secondary Surveillance Radar'', Stevens M.C. Artech House, is a radar system used in air traffic control (ATC), that unlike primary radar systems that measure the bearing and distance of targets using the detected reflections of radio signals, relies on targets equipped with a radar Transponder (aviation), transponder, that reply to each interrogation signal by transmitting encoded data such as an identity code, the aircraft's altitude and further information depending on its chosen mode. SSR is based on the military identification friend or foe (IFF) technology originally developed during World War II; therefore, the two systems are still compatible. Monopulse secondary surveillance radar (MSSR), Secondary surveillance radar#Mode S, Mode S, TCAS and ADS-B are similar modern methods of secondary surveillance. Overview Primary radar The rapid World War II, wartime development of radar had obvious applications for air traffic control (ATC) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surveillance
Surveillance is the monitoring of behavior, many activities, or information for the purpose of information gathering, influencing, managing, or directing. This can include observation from a distance by means of electronic equipment, such as closed-circuit television (CCTV), or interception of electronically transmitted information like Internet traffic. Increasingly, Government, governments may also obtain Customer data, consumer data through the purchase of online information, effectively expanding surveillance capabilities through commercially available digital records. It can also include simple technical methods, such as Human intelligence (intelligence gathering), human intelligence gathering and postal interception. Surveillance is used by citizens, for instance for protecting their neighborhoods. It is widely used by governments for intelligence gathering, including espionage, prevention of crime, the protection of a process, person, group or object, or the investigat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Air Navigation
The basic principles of air navigation are identical to general navigation, which includes the process of planning, recording, and controlling the movement of a craft from one place to another. Successful air navigation involves piloting an aircraft from place to place without getting lost, not breaking the laws applying to aircraft, or endangering the safety of those on board or on the ground. Air navigation differs from the navigation of surface craft in several ways; aircraft travel at relatively high speeds, leaving less time to calculate their position en route. Aircraft normally cannot stop in mid-air to ascertain their position at leisure. Aircraft are safety-limited by the amount of fuel they can carry; a surface vehicle can usually get lost, run out of fuel, then simply await rescue. There is no in-flight rescue for most aircraft. Additionally, collisions with obstructions are usually fatal. Therefore, constant awareness of position is critical for aircraft pilots. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
High Frequency
High frequency (HF) is the ITU designation for the band of radio waves with frequency between 3 and 30 megahertz (MHz). It is also known as the decameter band or decameter wave as its wavelengths range from one to ten decameters (ten to one hundred meters). Frequencies immediately below HF are denoted '' medium frequency'' (MF), while the next band of higher frequencies is known as the '' very high frequency'' (VHF) band. The HF band is a major part of the shortwave band of frequencies, so communication at these frequencies is often called ''shortwave radio''. Because radio waves in this band can be reflected back to Earth by the ionosphere layer in the atmosphere – a method known as "skip" or "skywave" propagation – these frequencies can be used for long-distance communication across intercontinental distances and for mountainous terrains which prevent line-of-sight communications. The band is used by international shortwave broadcasting stations (3.95–25.8 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eurocontrol
The European Organisation for the Safety of Air Navigation, commonly known as Eurocontrol (stylised ''EUROCONTROL''), is an international organisation working to achieve safe and seamless air traffic management across Europe. Founded in 1963, Eurocontrol currently has 42 member states with headquarters in Brussels, Belgium. It has several local sites as well, including an Innovation Hub in Brétigny-sur-Orge, France, the Aviation Learning Centre (ALC) in Luxembourg, and the Maastricht Upper Area Control Centre (MUAC) in Maastricht, Netherlands, the Netherlands. The organisation employs approximately two thousand people, and operates with an annual budget in excess of half a billion euros. Although Eurocontrol is not an agency of the European Union, the EU has delegated parts of its Single European Sky regulations to Eurocontrol, making it the central organisation for coordination and planning of air traffic control for all of Europe. The EU itself is a signatory of Eurocontrol and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ocean
The ocean is the body of salt water that covers approximately 70.8% of Earth. The ocean is conventionally divided into large bodies of water, which are also referred to as ''oceans'' (the Pacific, Atlantic, Indian Ocean, Indian, Southern Ocean, Antarctic/Southern, and Arctic Ocean),"Ocean." ''Merriam-Webster.com Dictionary'', Merriam-Webster, https://www.merriam-webster.com/dictionary/ocean . Accessed March 14, 2021. and are themselves mostly divided into seas, gulfs and Lists of bodies of water#Seawater bodies, subsequent bodies of water. The ocean contains 97% of Water distribution on Earth, Earth's water and is the primary component of Earth's hydrosphere, acting as a huge Ocean heat content, reservoir of heat for Earth's energy budget, as well as for its carbon cycle and water cycl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
