GSE is dedicated to serving all aspects of the satellite communications industry, including promoting education & learning. You may read about technologies and business practices - Here. If you need more information, use this glossary to find the meaning of any unfamiliar satellite communications related term.
Total number of glossary terms: 391
A device that measures proper acceleration ("g-force"). Proper acceleration is not the same as coordinate acceleration (rate of change of velocity). For example, an accelerometer at rest on the surface of the Earth will measure an acceleration g= 9.81 m/s2 straight upwards. By contrast, accelerometers in free fall orbiting and accelerating due to the gravity of Earth will measure zero.
View Source: http://en.wikipedia.org/wiki/Accelerometer
An analog-to-digital converter (ADC, A/D, or A to D) is a device that converts a continuous physical quantity (usually voltage) to a digital number that represents the quantity's amplitude.
View Source: https://en.wikipedia.org/wiki/Analog-to-digital_converter
The Advanced Encryption Standard (AES), also referenced as Rijndael (its original name), is a specification for the encryption of electronic data established by the U.S. National Institute of Standards and Technology (NIST) in 2001. AES is based on the Rijndael cipher developed by two Belgian cryptographers, Joan Daemen and Vincent Rijmen, who submitted a proposal to NIST during the AES selection process. Rijndael is a family of ciphers with different key and block sizes. For AES, NIST selected three members of the Rijndael family, each with a block size of 128 bits, but three different key lengths: 128, 192 and 256 bits.
View Source: http://en.wikipedia.org/wiki/Advanced_Encryption_Standard
Automated flight following (AFF) is GPS aircraft tracking that is mandated by a government agency (or other governing body) for its contractors. The following criteria must be met: - The device must transmit position reports every two minutes - The position reports must be pushed into the third-party database (where they are automatically tracked by dispatchers) Common uses for AFF devices are contractors flying for USDA during fire season and contractors flying for utility companies.
View Source: https://en.wikipedia.org/wiki/Automated_Flight_Following
Assisted GPS (abbreviated generally as A-GPS and less commonly as aGPS) is a system that is often able to significantly improve the startup performance, or time-to-first-fix (TTFF), of a GPS satellite-based positioning system. A-GPS is extensively used with GPS-capable cellular phones, as its development was accelerated by the U.S. FCC's 911 requirement to make cell phone location data available to emergency call dispatchers.
View Source: http://en.wikipedia.org/wiki/Assisted_GPS
The Automatic Identification System (AIS) is an automatic tracking system used on ships and by vessel traffic services (VTS) for identifying and locating vessels by electronically exchanging data with other nearby ships, AIS base stations, and satellites. When satellites are used to detect AIS signatures then the term Satellite-AIS (S-AIS) is used. AIS information supplements marine radar, which continues to be the primary method of collision avoidance for water transport.
View Source: http://en.wikipedia.org/wiki/Automatic_Identification_System
ANT is a proprietary open access multicast wireless sensor network technology designed and marketed by ANT Wireless. It features a wireless communications protocol stack that enables semiconductor radios operating in the 2.4 GHz industrial, scientific, and medical allocation of the RF spectrum ("ISM band") to communicate by establishing standard rules for co-existence, data representation, signalling, authentication, and error detection.
View Source: http://en.wikipedia.org/wiki/ANT_%28network%29
Application programming interface, is a set of routines, protocols, and tools for building software applications. The API specifies how software components should interact and APIs are used when programming graphical user interface (GUI) components.
View Source: https://en.wikipedia.org/wiki/Application_programming_interface
Abbreviated from American Standard Code for Information Interchange, is a character-encoding scheme. Originally based on the English alphabet, it encodes 128 specified characters into 7-bit binary integers as shown by the ASCII chart on the right. The characters encoded are numbers 0 to 9, lowercase letters a to z, uppercase letters A to Z, basic punctuation symbols, control codes that originated with Teletype machines, and a space. For example, lowercase j would become binary 1101010 and decimal 106. ASCII codes represent text in computers, communications equipment, and other devices that use text. Most modern character-encoding schemes are based on ASCII, though they support many additional characters.
View Source: https://en.wikipedia.org/wiki/ASCII
An application-specific integrated circuit (ASIC) /ˈeɪsɪk/, is an integrated circuit (IC) customized for a particular use, rather than intended for general-purpose use. For example, a chip designed to run in a digital voice recorder or a high-efficiency Bitcoin miner is an ASIC. These are commonly used in satellite communications equipment for specialized RF or waveform modulation.
View Source: https://en.wikipedia.org/wiki/Application-specific_integrated_circuit
Fixed signal loss due to cabling or reduction of signal strength due to atmospheric conditions.
View Source: https://en.wikipedia.org/wiki/Attenuation
Automatic Vehicle Location - SkyWave's agent with an embedded Lua application designed to reduce time and programming costs when integrating IsatData Pro satellite and satellite-cellular terminals into existing fleet management applications.
View Source: http://www.skywave.com/en/our-technology/applications/avl-agent
The Broadband Global Area Network (BGAN) is a global satellite internet network with telephony using portable terminals. The terminals are normally used to connect a laptop computer to broadband Internet in remote locations, although as long as line-of-sight to the satellite exists, the terminal can be used anywhere. The value of BGAN terminals is that unlike other satellite Internet services which require bulky and heavy satellite dishes to connect, a BGAN terminal is about the size of a laptop and thus can be carried easily. The network is provided by Inmarsat and uses three geostationary satellites called I-4 to provide almost global coverage.
View Source: http://www.inmarsat.com/service/bgan/
A wireless technology standard for exchanging data over short distances (using short-wavelength UHF radio waves in the ISM band from 2.4 to 2.485 GHz) from fixed and mobile devices, and building personal area networks (PANs). Invented by telecom vendor Ericsson in 1994, it was originally conceived as a wireless alternative to RS-232 data cables. It can connect several devices, overcoming problems of synchronization.
View Source: http://en.wikipedia.org/wiki/Bluetooth
A controller area network (CAN bus) is a vehicle bus standard designed to allow microcontrollers and devices to communicate with each other in applications without a host computer. It is a message-based protocol, designed originally for automotive applications, but is also used in many other contexts. CAN bus is one of five protocols used in the on-board diagnostics (OBD)-II vehicle diagnostics standard. The OBD-II standard has been mandatory for all cars and light trucks sold in the United States since 1996, and the EOBD standard has been mandatory for all petrol vehicles sold in the European Union since 2001 and all diesel vehicles since 2004.
View Source: https://en.wikipedia.org/wiki/CAN_bus
A controller area network (CAN bus) is a vehicle bus standard designed to allow microcontrollers and devices to communicate with each other in applications without a host computer. It is a message-based protocol, designed originally for automotive applications, but is also used in many other contexts. CAN bus is one of five protocols used in the on-board diagnostics (OBD)-II vehicle diagnostics standard. The OBD-II standard has been mandatory for all cars and light trucks sold in the United States since 1996, and the EOBD standard has been mandatory for all petrol vehicles sold in the European Union since 2001 and all diesel vehicles since 2004.
View Source: https://en.wikipedia.org/wiki/CAN_bus
The art and science of graphically representing a geographical area, usually on a flat surface such as a map or chart; it may involve the superimposition of political, cultural, or other nongeographical divisions onto the representation of a geographical area.
View Source: http://www.britannica.com/EBchecked/topic/97492/cartography
Circular Error Probability or CEP is defined as the radius of a circle centered on the true value that contains 50% of the actual GPS measurements. So a receiver with 1 meter CEP accuracy will be within one meter of the true measurement 50% of the time. The other 50% of the time the measurement will be in error by more than one meter.
View Source: https://en.wikipedia.org/wiki/Circular_error_probable
In a computer system, a chipset is a set of electronic components in an integrated circuit that manages the data flow between the processor, memory and peripherals. It is usually found on the motherboard. Chipsets are usually designed to work with a specific family of microprocessors. Because it controls communications between the processor and external devices, the chipset plays a crucial role in determining system performance.
View Source: https://en.wikipedia.org/wiki/Chipset
In telecommunications, the carrier-to-noise ratio, often written CNR or C/N, is the signal-to-noise ratio (SNR) of a modulated signal. The term is used to distinguish the CNR of the radio frequency passband signal from the SNR of an analogue base band message signal after demodulation, for example an audio frequency analogue message signal. If this distinction is not necessary, the term SNR is often used instead of CNR, with the same definition. High C/N ratios provide good quality of reception, for example low bit error rate (BER) of a digital message signal, or high SNR of an analogue message signal.
View Source: https://en.wikipedia.org/wiki/Carrier-to-noise_ratio
Constrained Application Protocol (CoAP) is a software protocol intended to be used in very simple electronics devices that allows them to communicate interactively over the Internet. It is particularly targeted for small low power sensors, switches, valves and similar components that need to be controlled or supervised remotely, through standard Internet networks. CoAP is an application layer protocol that is intended for use in resource-constrained internet devices, such as WSN nodes. CoAP is designed to easily translate to HTTP for simplified integration with the web, while also meeting specialized requirements such as multicast support, very low overhead, and simplicity. Multicast, low overhead, and simplicity are extremely important for Internet of Things (IoT) and Machine-to-Machine (M2M) devices, which tend to be deeply embedded and have much less memory and power supply than traditional internet devices have. Therefore, efficiency is very important. CoAP can run on most devices that support UDP or a UDP analogue.
View Source: https://en.wikipedia.org/wiki/Constrained_Application_Protocol
The C band is a name given to certain portions of the electromagnetic spectrum, including wavelengths of microwaves that are used for long-distance radio telecommunications. The IEEE C-band (4 to 8 GHz) and its slight variations contain frequency ranges that are used for many satellite communications transmissions, some Wi-Fi devices, some cordless telephones, and some weather radar systems. For satellite communications, the microwave frequencies of the C-band perform better under adverse weather conditions in comparison with the Ku band (11.2 GHz to 14.5 GHz) microwave frequencies used by other communication satellites.
View Source: https://en.wikipedia.org/wiki/C_band
Differential Global Positioning System (DGPS) is an enhancement to Global Positioning System that provides improved location accuracy, from the 15-meter nominal GPS accuracy to about 10 cm in case of the best implementations. DGPS uses a network of fixed, ground-based reference stations to broadcast the difference between the positions indicated by the GPS (satellite) systems and the known fixed positions. These stations broadcast the difference between the measured satellite pseudoranges and actual (internally computed) pseudoranges, and receiver stations may correct their pseudoranges by the same amount. The digital correction signal is typically broadcast locally over ground-based transmitters of shorter range.
View Source: https://en.wikipedia.org/wiki/Differential_GPS
The Domain Name System (DNS) is a hierarchical distributed naming system for computers, services, or any resource connected to the Internet or a private network. It associates various information with domain names assigned to each of the participating entities. Most prominently, it translates domain names, which can be easily memorized by humans, to the numerical IP addresses needed for the purpose of computer services and devices worldwide. The Domain Name System is an essential component of the functionality of most Internet services because it is the Internet's primary directory service.
View Source: http://en.wikipedia.org/wiki/Domain_Name_System
Dilution of precision (DOP), or geometric dilution of precision (GDOP), is a term used in satellite navigation and geomatics engineering to specify the additional multiplicative effect of navigation satellite geometry on positional measurement precision. Due to the relative geometry of any given satellite to a receiver, the precision in the pseudorange of the satellite translates to a corresponding component in each of the four dimensions of position measured by the receiver (i.e., x, y, z, and t). The precision of multiple satellites in view of a receiver combine according to the relative position of the satellites to determine the level of precision in each dimension of the receiver measurement. When visible navigation satellites are close together in the sky, the geometry is said to be weak and the DOP value is high; when far apart, the geometry is strong and the DOP value is low. Consider two overlapping rings, or annuli, of different centres. If they overlap at right angles, the greatest extent of the overlap is much smaller than if they overlap in near parallel. Thus a low DOP value represents a better positional precision due to the wider angular separation between the satellites used to calculate a unit's position. Other factors that can increase the effective DOP are obstructions such as nearby mountains or buildings. DOP can be expressed as a number of separate measurements. HDOP, VDOP, PDOP, and TDOP are respectively Horizontal, Vertical, Position (3D), and Time Dilution of Precision.
View Source: https://en.wikipedia.org/wiki/Dilution_of_precision_(GPS)
The Doppler effect (or Doppler shift) is the change in frequency of a wave (or other periodic event) for an observer moving relative to its source. Fast moving satellites can have a Doppler shift of dozens of kilohertz relative to a ground station. The speed, thus magnitude of Doppler effect, changes due to earth curvature. Dynamic Doppler compensation, where the frequency of a signal is changed multiple times during transmission, is used so the satellite receives a constant frequency signal.
View Source: https://en.wikipedia.org/wiki/Doppler_effect#Satellite_communication
Modern OBD implementations use a standardized digital communications port to provide real-time data in addition to a standardized series of diagnostic trouble codes, or DTCs, which allow one to rapidly identify and remedy malfunctions within the vehicle.
View Source: https://en.wikipedia.org/wiki/On-board_diagnostics#EOBD_fault_codes
If your item falls under the jurisdiction of the U.S. Department of Commerce and is not listed on the CCL, it is designated as EAR99. The majority of commercial products are designated EAR99 and generally will not require a license to be exported or reexported. However, if you plan to export an EAR99 item to an embargoed or sanctioned country, to a party of concern, or in support of a prohibited end-use, you may be required to obtain a license.
An Export Control Classification Number (ECCN) is an alphanumeric code assigned to articles, technology and software (collectively, "items") by the US Department of Commerce, Bureau of Industry and Security. Each ECCN provides for varying degrees of export control based on the country of end use.
View Source: https://en.wikipedia.org/wiki/Export_Administration_Regulations
In automotive electronics, Electronic Control Unit (ECU) is a generic term for any embedded system that controls one or more of the electrical system or subsystems in a transport vehicle.
View Source: https://en.wikipedia.org/wiki/Electronic_control_unit
Electrostatic discharge (ESD) is the sudden flow of electricity between two electrically charged objects caused by contact, an electrical short, or dielectric breakdown. A buildup of static electricity can be caused by tribocharging or by electrostatic induction. The ESD occurs when differently-charged objects are brought close together or when the dielectric between them breaks down, often creating a visible spark.
View Source: https://en.wikipedia.org/wiki/Electrostatic_discharge
eLua stands for Embedded Lua and the project offers the full implementation of the Lua Programming Language to the embedded world, extending it with specific features for efficient and portable software embedded development
View Source: http://www.eluaproject.net/overview
In cryptography, encryption is the process of encoding messages or information in such a way that only authorized parties can read it. Encryption does not of itself prevent interception, but denies the message content to the interceptor.
View Source: https://en.wikipedia.org/wiki/Encryption
Electrostatic Discharge is the sudden flow of electricity between two electrically charged objects caused by contact, which is often caused by humans building up a charge while walking or other contact.
View Source: http://en.wikipedia.org/wiki/Electrostatic_discharge
Electrostatic discharge (ESD) is the sudden flow of electricity between two electrically charged objects caused by contact, an electrical short, or dielectric breakdown. A buildup of static electricity can be caused by tribocharging or by electrostatic induction. The ESD occurs when differently-charged objects are brought close together or when the dielectric between them breaks down, often creating a visible spark.
View Source: https://en.wikipedia.org/wiki/Electrostatic_discharge
Electronic serial numbers (ESNs) were created by the U.S. Federal Communications Commission (FCC) to uniquely identify mobile devices, from the days of AMPS in the United States starting in the early 1980s. The administrative role was taken over by the Telecommunications Industry Association in 1997 and is still maintained by them. ESNs are currently mainly used with CDMA phones (and were previously used by AMPS and TDMA phones), compared to International Mobile Equipment Identity (IMEI) numbers used by all GSM phones.
View Source: https://en.wikipedia.org/wiki/Electronic_serial_number
Fleet management includes commercial motor vehicles such as cars, aircraft (planes, helicopters etc.), ships, vans and trucks, as well as rail cars. Fleet (vehicle) management can include a range of functions, such as vehicle financing, vehicle maintenance, vehicle telematics (tracking and diagnostics), driver management, speed management, fuel management and health and safety management. Fleet Management is a function which allows companies which rely on transportation in business to remove or minimize the risks associated with vehicle investment, improving efficiency, productivity and reducing their overall transportation and staff costs, providing 100% compliance with government legislation (duty of care) and many more.
View Source: http://en.wikipedia.org/wiki/Fleet_management
Fixed-satellite service (FSS) – A radio-communication service between earth stations at given positions, when one or more satellites are used; the given position may be a specified fixed point or any fixed point within specified areas; in some cases this service includes satellite-to-satellite links, which may also be operated in the inter-satellite service; the fixed-satellite service may also include feeder links for other space radiocommunication services.
View Source: http://en.wikipedia.org/wiki/Fixed-satellite_service
Fuel management systems are used to maintain, control and monitor fuel consumption and stock in any type of industry that uses transport, including rail, road, water and air, as a means of business. Fuel management systems are designed to effectively measure and manage the use of fuel within the transportation and construction industries. They are typically used for fleets of vehicles, including railway vehicles and aircraft, as well as any vehicle that requires fuel to operate. They employ various methods and technologies to monitor and track fuel inventories, fuel purchases and fuel dispensed. This information can be then stored in computerized systems and reports generated with data to inform management practices. Online fuel management is provided through the use of web portals to provide detailed fueling data, usually vis a vis the back end of an automated fuel management system. This enables consumption control, cost analysis and tax accounting for fuel purchases.
View Source: http://en.wikipedia.org/wiki/Fuel_management_systems
Antenna gain-to-noise-temperature (G/T) is a figure of merit in the characterization of antenna performance, where G is the antenna gain in decibels at the receive frequency, and T is the equivalent noise temperature of the receiving system in kelvins. T is the summation of the antenna noise temperature and the RF chain noise temperature from the antenna terminals to the receiver output. Satellite antenna aperture is closely related to quality factor（G/T value）of earth station. G/T value and satellite power demand, i.e. equivalent rent bandwidth, show logarithmic linear relationship. In other words, the value of equivalent rent bandwidth increases with the narrowing of antenna aperture. Therefore, when selecting earth station aperture, it is not the smaller, the better.
View Source: https://en.wikipedia.org/wiki/Antenna_gain-to-noise-temperature
Antenna gain-to-noise-temperature (G/T) is a figure of merit in the characterization of antenna performance, where G is the antenna gain in decibels at the receive frequency, and T is the equivalent noise temperature of the receiving system in kelvins. T is the summation of the antenna noise temperature and the RF chain noise temperature from the antenna terminals to the receiver output. Satellite antenna aperture is closely related to quality factor（G/T value）of earth station. G/T value and satellite power demand, i.e. equivalent rent bandwidth, show logarithmic linear relationship. In other words, the value of equivalent rent bandwidth increases with the narrowing of antenna aperture. Therefore, when selecting earth station aperture, it is not the smaller, the better.
View Source: https://en.wikipedia.org/wiki/Antenna_gain-to-noise-temperature
Galileo is the global navigation satellite system (GNSS) that is currently being created by the European Union (EU) and the European Space Agency (ESA). The €5 billion project is named after the Italian astronomer Galileo Galilei. One of the aims of Galileo is to provide an indigenous alternative high-precision positioning system upon which European nations can rely, independently from the Russian GLONASS and US GPS systems, in case they were disabled by their operators. The use of basic (low-precision) Galileo services will be free and open to everyone. The high-precision capabilities will be available for paying commercial users. Galileo is intended to provide horizontal and vertical position measurements within 1-metre precision, and better positioning services at high latitudes than other positioning systems.
View Source: http://en.wikipedia.org/wiki/Galileo_%28satellite_navigation%29
A special geosynchronous orbit which is circular and lying over the equator such that the satellite seems to remain stationary in the sky as seem from a location on the surface of Earth.
View Source: http://en.wikipedia.org/wiki/Geostationary_orbit
A geographic information system (GIS) is a system designed to capture, store, manipulate, analyze, manage, and present all types of spatial or geographical data.
View Source: http://education.nationalgeographic.com/education/encyclopedia/geographic-information-system-gis/?ar_a=1
A space-based satellite navigation system operated by the Russian Aerospace Defence Forces. It provides an alternative to Global Positioning System (GPS) and is the second alternative navigational system in operation with global coverage and of comparable precision.
View Source: http://en.wikipedia.org/wiki/GLONASS
GNSS stands for Global Navigation Satellite System, and is the standard generic term for satellite navigation systems that provide autonomous geo-spatial positioning with global coverage. This term includes e.g. the GPS, GLONASS, Galileo, Beidou and other regional systems.
View Source: http://en.wikipedia.org/wiki/Satellite_navigation
General packet radio service (GPRS) is a packet oriented mobile data service on the 2G and 3G cellular communication system's global system for mobile communications (GSM). GPRS was originally standardized by European Telecommunications Standards Institute (ETSI) in response to the earlier CDPD and i-mode packet-switched cellular technologies. It is now maintained by the 3rd Generation Partnership Project (3GPP). GPRS usage is typically charged based on volume of data transferred, contrasting with circuit switched data, which is usually billed per minute of connection time. Usage above the bundle cap is either charged per megabyte or disallowed.
View Source: https://en.wikipedia.org/wiki/General_Packet_Radio_Service
The Global Positioning System (GPS) is a space-based satellite navigation system that provides location and time information in all weather conditions, anywhere on or near the earth where there is an unobstructed line of sight to four or more GPS satellites. The system provides critical capabilities to military, civil, and commercial users around the world. The United States government created the system, maintains it, and makes it freely accessible to anyone with a GPS receiver.
View Source: http://en.wikipedia.org/wiki/Global_Positioning_System
A ground station, earth station, or earth terminal is a terrestrial radio station designed for extraplanetary telecommunication with spacecraft, or reception of radio waves from an astronomical radio source. Ground stations are located either on the surface of the Earth or in its atmosphere. Earth stations communicate with spacecraft by transmitting and receiving radio waves in the super high frequency or extremely high frequency bands (e.g., microwaves). When a ground station successfully transmits radio waves to a spacecraft (or vice versa), it establishes a telecommunications link. A principal telecommunications device of the ground station is the parabolic antenna.
View Source: http://en.wikipedia.org/wiki/Ground_station
GSM (Global System for Mobile Communications, originally Groupe Spécial Mobile), is a standard developed by the European Telecommunications Standards Institute (ETSI) to describe protocols for second-generation (2G) digital cellular networks used by mobile phones, first deployed in Finland in July 1992. As of 2014 it has become the default global standard for mobile communications - with over 90% market share, operating in over 219 countries and territories.
View Source: http://en.wikipedia.org/wiki/GSM
Dilution of precision (DOP), or geometric dilution of precision (GDOP), is a term used in satellite navigation and geomatics engineering to specify the additional multiplicative effect of navigation satellite geometry on positional measurement precision. Due to the relative geometry of any given satellite to a receiver, the precision in the pseudorange of the satellite translates to a corresponding component in each of the four dimensions of position measured by the receiver (i.e., x, y, z, and t). The precision of multiple satellites in view of a receiver combine according to the relative position of the satellites to determine the level of precision in each dimension of the receiver measurement. When visible navigation satellites are close together in the sky, the geometry is said to be weak and the DOP value is high; when far apart, the geometry is strong and the DOP value is low. Consider two overlapping rings, or annuli, of different centres. If they overlap at right angles, the greatest extent of the overlap is much smaller than if they overlap in near parallel. Thus a low DOP value represents a better positional precision due to the wider angular separation between the satellites used to calculate a unit's position. Other factors that can increase the effective DOP are obstructions such as nearby mountains or buildings. DOP can be expressed as a number of separate measurements. HDOP, VDOP, PDOP, and TDOP are respectively Horizontal, Vertical, Position (3D), and Time Dilution of Precision.
View Source: https://en.wikipedia.org/wiki/Dilution_of_precision_(GPS)
A helical antenna is an antenna consisting of a conducting wire wound in the form of a helix. In most cases, helical antennas are mounted over a ground plane. The feed line is connected between the bottom of the helix and the ground plane. Helical antennas can operate in one of two principal modes — normal mode or axial mode. In the normal mode or broadside helix, the dimensions of the helix (the diameter and the pitch) are small compared with the wavelength. The antenna acts similarly to an electrically short dipole or monopole, and the radiation pattern, similar to these antennas is omnidirectional, with maximum radiation at right angles to the helix axis. The radiation is linearly polarised parallel to the helix axis. In the axial mode or end-fire helix, the dimensions of the helix are comparable to a wavelength. The antenna functions as a directional antenna radiating a beam off the ends of the helix, along the antenna's axis. It radiates circularly polarised radio waves.
View Source: http://en.wikipedia.org/wiki/Helical_antenna
A high-gain antenna (HGA) is an antenna with a focused, narrow radiowave beam width. This narrow beam width allows more precise targeting of the radio signal - also known as a directional antenna. Most commonly referred to during space missions, these antennas are also in use all over Earth, most successfully in flat, open areas where no mountains lie to disrupt radiowaves.
View Source: https://en.wikipedia.org/?title=High-gain_antenna
A high-gain antenna (HGA) is an antenna with a focused, narrow radiowave beam width. This narrow beam width allows more precise targeting of the radio signal - also known as a directional antenna. Most commonly referred to during space missions, these antennas are also in use all over Earth, most successfully in flat, open areas where no mountains lie to disrupt radiowaves.
View Source: https://en.wikipedia.org/?title=High-gain_antenna
Hysteresis is the time-based dependence of a system's output on current and past inputs. The dependence arises because the history affects the value of an internal state. To predict its future outputs, either its internal state or its history must be known.
View Source: https://en.wikipedia.org/wiki/Hysteresis
In computing, input/output or I/O (or informally, io or IO) is the communication between an information processing system (such as a computer) and the outside world, possibly a human or another information processing system.
View Source: http://en.wikipedia.org/wiki/Input/output
The International Mobile Station Equipment Identity or IMEI is a number, usually unique, to identify 3GPP (i.e., GSM, UMTS and LTE) and iDEN mobile phones, as well as some satellite phones. It is usually found printed inside the battery compartment of the phone, but can also be displayed on-screen on most phones by entering *#06# on the dialpad, or alongside other system information in the settings menu on smartphone operating systems.
View Source: https://en.wikipedia.org/wiki/International_Mobile_Station_Equipment_Identity
The International Mobile Subscriber Identity or IMSI is used to identify the user of a cellular network and is a unique identification associated with all cellular networks. It is stored as a 64 bit field and is sent by the phone to the network. It is also used for acquiring other details of the mobile in the home location register (HLR) or as locally copied in the visitor location register. To prevent eavesdroppers identifying and tracking the subscriber on the radio interface, the IMSI is sent as rarely as possible and a randomly generated TMSI is sent instead.
View Source: https://en.wikipedia.org/wiki/International_mobile_subscriber_identity
A global two-way short message service for machine-to-machine (M2M) communication. Enables companies to track and monitor their fixed or mobile assets, giving them increased visibility of business operations, enhanced efficiency, and greater safety and security for their assets, cargo and drivers – while lowering operational costs.
View Source: http://www.inmarsat.com/service/isatdata-pro/
Integrated Services for Digital Network (ISDN) is a set of communication standards for simultaneous digital transmission of voice, video, data, and other network services over the traditional circuits of the public switched telephone network.
View Source: https://en.wikipedia.org/wiki/Integrated_Services_Digital_Network
K band designates certain portions of the electromagnetic spectrum, in either the microwave domain or in the infrared domain. The microwave K bands are used primarily for radar and satellite communications while the infrared K band is used for astronomical observations. NATO K band frequency range: 20 – 40 GHz // IEEE K band frequency range: 18 – 27 GHz
View Source: http://en.wikipedia.org/wiki/K_band
The Ka band ("kay-ay band") covers the frequencies of 26.5–40 GHz, i.e. wavelengths from slightly over one centimeter down to 7.5 milimeters. The Ka band is part of the K band of the microwave band of the electromagnetic spectrum. This symbol refers to "K-above": in other words, the band directly above the K-band. The 30/20 GHz band is used in communications satellites, uplink in either the 27.5 GHz and 31 GHz bands, and high-resolution, close-range targeting radars aboard military airplanes. Some frequencies in this radio band are used for vehicle speed detection by law enforcement. Kepler Mission uses this frequency range to downlink the scientific data collected by the space telescope. In satellite communications, the Ka band allows higher bandwidth communication. It is used in the Inmarsat I-5 system and will be used in the upcoming Newsat Jabiru, and Iridium Next satellite series, for instance. The Ka band is more susceptible to rain attenuation than is the Ku band, which in turn is more susceptible than the C band.
View Source: https://en.wikipedia.org/wiki/Ka_band
Keyhole Markup Language (KML) is an XML notation for expressing geographic annotation and visualization within Internet-based, two-dimensional maps and three-dimensional Earth browsers. KML was developed for use with Google Earth, which was originally named Keyhole Earth Viewer.
View Source: http://en.wikipedia.org/wiki/Keyhole_Markup_Language
The Ku band is the 12–18 GHz portion of the electromagnetic spectrum in the microwave range of frequencies. This symbol refers to "K-under"—in other words, the band directly below the K-band. In radar applications, it ranges from 12-18 GHz according to the formal definition of radar frequency band nomenclature in IEEE Standard 521-2002. Ku band is primarily used for satellite communications, most notably for fixed and broadcast services, and for specific applications such as NASA's Tracking Data Relay Satellite used for both space shuttle and International Space Station (ISS) communications.
View Source: https://en.wikipedia.org/wiki/Ku_band
L Band is the 1 to 2 GHz range of the radio spectrum and is very popular for satellite communications. It is a good balance of antenna size, bandwidth, and atmospheric interference. Ionospheric scintillations are worse at lower frequencies than high. VHF frequencies, such as the 240 MHz frequencies used in military communications, suffer the most, while L-band is moderately affected, and only the strongest scintillations affect C-band and above.
View Source: http://en.wikipedia.org/wiki/L_band
In geography, latitude (φ) is a geographic coordinate that specifies the north–south position of a point on the Earth's surface.
View Source: https://en.wikipedia.org/wiki/Latitude
Location Based Services - The Iridium Extreme™ GPS and Location-Based Service features allow you to view, send, or restrict your location information. There are four main components to setup and use these features: 1.) Location Options Setup Menu: located in the Iridium Extreme™ main menu in the setup section, Location Options Options is where you customize your GPS, emergency, message, and format options. 2.) Programmable SOS button: this red button is located on the top of the phone, under a protective cover. By removing the cover and and pressing the red button you can send your location information to your designated contact in the event of an emergency. 3.) Location Convenience Key: located on the right side of the phone, you can to press this key to view your location and share it via SMS to either a pre-programmed “Quick GPS” contacts or a new message contact. 4.) Online portal integration with 3rd party providers: enables the transmission of the phone’s location information on a scheduled interval via short-burst data (SBD) to 3rd party portal providers for online tracking
View Source: http://www.groundcontrol.com/iridium/Iridium_Extreme_Location_Based_Services.pdf
A leap second is a one-second adjustment that is occasionally applied to Coordinated Universal Time (UTC) in order to keep its time of day close to the mean solar time, or UT1. Without such a correction, time reckoned by Earth's rotation drifts away from atomic time because of irregularities in the Earth's rate of rotation. Since this system of correction was implemented in 1972, 25 such leap seconds have been inserted. The most recent one happened on June 30, 2012 at 23:59:60 UTC. A leap second, the 26th, will again be inserted at the end of June 30, 2015 at 23:59:60 UTC.
View Source: https://en.wikipedia.org/wiki/Leap_second
A lithium polymer battery, or more correctly lithium-ion polymer battery (abbreviated variously as LiPo, LIP, Li-poly and others), is a rechargeable battery of lithium-ion technology in a pouch format. Unlike cylindrical and prismatic cells, LiPos come in a soft package or pouch, which makes them lighter but also lack rigidity.
View Source: https://en.wikipedia.org/wiki/Lithium_polymer_battery
Longitude is a geographic coordinate that specifies the east-west position of a point on the Earth's surface.
View Source: https://en.wikipedia.org/wiki/Longitude
LoRaWAN™ is a Low Power Wide Area Network (LPWAN) specification intended for wireless battery operated Things in regional, national or global network. LoRaWAN target key requirements of internet of things such as secure bi-directional communication, mobility and localization services. This standard will provide seamless interoperability among smart Things without the need of complex local installations and gives back the freedom to the user, developer, businesses enabling the roll out of Internet of Things.
View Source: https://www.lora-alliance.org/What-Is-LoRa/Technology
LoRaWAN™ is a Low Power Wide Area Network (LPWAN) specification intended for wireless battery operated Things in regional, national or global network. LoRaWAN target key requirements of internet of things such as secure bi-directional communication, mobility and localization services. This standard will provide seamless interoperability among smart Things without the need of complex local installations and gives back the freedom to the user, developer, businesses enabling the roll out of Internet of Things.
View Source: https://www.lora-alliance.org/What-Is-LoRa/Technology
A low Earth orbit (LEO) is an orbit around Earth with an altitude between 160 kilometers (99 mi) (orbital period of about 88 minutes), and 2,000 kilometers (1,200 mi) (about 127 minutes). Objects below approximately 160 kilometers (99 mi) will experience very rapid orbital decay and altitude loss.
View Source: http://en.wikipedia.org/wiki/Low_Earth_orbit
A powerful, fast, lightweight, embeddable scripting language. Lua combines simple procedural syntax with powerful data description constructs based on associative arrays and extensible semantics. Lua is dynamically typed, runs by interpreting bytecode for a register-based virtual machine, and has automatic memory management with incremental garbage collection, making it ideal for configuration, scripting, and rapid prototyping.
View Source: http://www.lua.org/about.html
Machine to Machine (M2M) refers to technologies that allow both wireless and wired systems to communicate with other devices of the same type. M2M is a broad term as it does not pinpoint specific wireless or wired networking, information and communications technology. This broad term is particularly used by business executives. M2M is considered an integral part of the Internet of Things (IoT) and brings several benefits to industry and business in general as it has a wide range of applications such as industrial automation, logistics, Smart Grid, Smart Cities, health, defense etc. mostly for monitoring but also for control purposes.
View Source: https://en.wikipedia.org/wiki/Machine_to_machine
Medium Earth orbit (MEO), sometimes called intermediate circular orbit (ICO), is the region of space around the Earth above low Earth orbit (altitude of 2,000 kilometres (1,243 mi)) and below geostationary orbit (altitude of 35,786 kilometres (22,236 mi)). The most common use for satellites in this region is for navigation, communication, and geodetic/space environment science. The most common altitude is approximately 20,200 kilometres (12,552 mi)), which yields an orbital period of 12 hours, as used, for example, by the Global Positioning System (GPS). Other satellites in Medium Earth Orbit include Glonass (with an altitude of 19,100 kilometres (11,868 mi)) and Galileo (with an altitude of 23,222 kilometres (14,429 mi)) constellations. Communications satellites that cover the North and South Pole are also put in MEO.
View Source: http://en.wikipedia.org/wiki/Medium_Earth_orbit
The Mercator projection is a cylindrical map projection presented by the Flemish geographer and cartographer Gerardus Mercator in 1569. It became the standard map projection for nautical purposes because of its ability to represent lines of constant course, known as rhumb lines or loxodromes, as straight segments that conserve the angles with the meridians. While the linear scale is equal in all directions around any point, thus preserving the angles and the shapes of small objects (which makes the projection conformal), the Mercator projection distorts the size of objects as the latitude increases from the Equator to the poles, where the scale becomes infinite. So, for example, Greenland and Antarctica appear much larger relative to land masses near the equator than they actually are.
View Source: https://en.wikipedia.org/wiki/Mercator_projection
The military grid reference system (MGRS) is the geocoordinate standard used by NATO militaries for locating points on the earth. The MGRS is derived from the Universal Transverse Mercator (UTM) grid system and the universal polar stereographic (UPS) grid system, but uses a different labeling convention. The MGRS is used for the entire earth.
View Source: http://en.wikipedia.org/wiki/Military_grid_reference_system
A microcontroller (sometimes abbreviated µC, uC or MCU) is a small computer on a single integrated circuit containing a processor core, memory, and programmable input/output peripherals. Program memory in the form of Ferroelectric RAM, NOR flash or OTP ROM is also often included on chip, as well as a typically small amount of RAM. Microcontrollers are designed for embedded applications, in contrast to the microprocessors used in personal computers or other general purpose applications.
View Source: http://en.wikipedia.org/wiki/Microcontroller
Milankovitch theory describes the collective effects of changes in the Earth's movements upon its climate, named after Serbian geophysicist and astronomer Milutin Milanković, who worked on it during his internment as a POW during the First World War. Milanković mathematically theorized that variations in eccentricity, axial tilt, and precession of the Earth's orbit determined climatic patterns on Earth through orbital forcing. The Earth's axis completes one full cycle of precession approximately every 26,000 years. At the same time, the elliptical orbit rotates more slowly. The combined effect of the two precessions leads to a 21,000-year period between the astronomical seasons and the orbit. In addition, the angle between Earth's rotational axis and the normal to the plane of its orbit (obliquity) oscillates between 22.1 and 24.5 degrees on a 41,000-year cycle. It is currently 23.44 degrees and decreasing.
View Source: https://en.wikipedia.org/wiki/Milankovitch_cycles
A Maritime Mobile Service Identity (MMSI) is a series of nine digits which are sent in digital form over a radio frequency channel in order to uniquely identify ship stations, ship earth stations, coast stations, coast earth stations, and group calls. These identities are formed in such a way that the identity or part thereof can be used by telephone and telex subscribers connected to the general telecommunications network to call ships automatically.
View Source: http://en.wikipedia.org/wiki/Maritime_Mobile_Service_Identity
The National Marine Electronics Association (NMEA) is a US-based marine electronics trade organisation setting standards of communication between marine electronics. NMEA standards include: NMEA 0180, NMEA 0182, NMEA 0183, NMEA 2000, NMEA OneNet
View Source: https://en.wikipedia.org/wiki/National_Marine_Electronics_Association
NMEA 2000, abbreviated to NMEA2k or N2K and standardised as IEC 61162-3, is a plug-and-play communications standard used for connecting marine sensors and display units within ships and boats. Communication runs at 250 kilobits-per-second and allows any sensor to talk to any display unit or other device compatible with NMEA 2000 protocols. Electrically NMEA 2000 is compatible with the Controller Area Network ("CAN Bus") used on road vehicles and fuel engines. The higher-level protocol format is based on SAE J1939, with specific messages for the marine environment. The protocol is used to create a network of electronic devices—chiefly marine instruments—on a boat. Various instruments that meet the NMEA 2000 standard are connected to one central cable, known as a backbone. The backbone powers each instrument and relays data among all of the instruments on the network. This allows one display unit to show many different types of information. It also allows the instruments to work together, since they share data. NMEA 2000 is meant to be "plug and play" to allow devices made by different manufacturers to talk and listen to each other.
View Source: https://en.wikipedia.org/wiki/NMEA_2000
The National Oceanic and Atmospheric Administration is an American scientific agency within the United States Department of Commerce focused on the conditions of the oceans and the atmosphere. NOAA warns of dangerous weather, charts seas and skies, guides the use and protection of ocean and coastal resources, and conducts research to improve understanding and stewardship of the environment.
View Source: https://en.wikipedia.org/wiki/National_Oceanic_and_Atmospheric_Administration
Non-recurring engineering (NRE) - refers to the one-time cost to research, develop, design and test a new product. When budgeting for a project, NRE must be considered to analyze if a new product will be profitable. Even though a company will pay for NRE on a project only once, NRE costs can be prohibitively high and the product will need to sell well enough to produce a return on the initial investment. NRE is unlike production costs, which must be paid constantly to maintain production of a product. It is a form of fixed cost in economics terms. Once a system is designed any number of units can be manufactured without increasing NRE cost.
View Source: https://en.wikipedia.org/wiki/Non-recurring_engineering
Non-recurring engineering (NRE) - refers to the one-time cost to research, develop, design and test a new product. When budgeting for a project, NRE must be considered to analyze if a new product will be profitable. Even though a company will pay for NRE on a project only once, NRE costs can be prohibitively high and the product will need to sell well enough to produce a return on the initial investment. NRE is unlike production costs, which must be paid constantly to maintain production of a product. It is a form of fixed cost in economics terms. Once a system is designed any number of units can be manufactured without increasing NRE cost.
View Source: https://en.wikipedia.org/wiki/Non-recurring_engineering
On-board diagnostics (OBD) is an automotive term referring to a vehicle's self-diagnostic and reporting capability. OBD systems give the vehicle owner or repair technician access to the status of the various vehicle subsystems. The amount of diagnostic information available via OBD has varied widely since its introduction in the early 1980s versions of on-board vehicle computers. Early versions of OBD would simply illuminate a malfunction indicator light or "idiot light" if a problem was detected but would not provide any information as to the nature of the problem. Modern OBD implementations use a standardized digital communications port to provide real-time data in addition to a standardized series of diagnostic trouble codes, or DTCs, which allow one to rapidly identify and remedy malfunctions within the vehicle.
View Source: https://en.wikipedia.org/wiki/On-board_diagnostics
In radio communication, an omnidirectional antenna is a class of antenna which radiates radio wave power uniformly in all directions in one plane, with the radiated power decreasing with elevation angle above or below the plane, dropping to zero on the antenna's axis. This radiation pattern is often described as "doughnut shaped". Note that this is different from an isotropic antenna, which radiates equal power in all directions and has a "spherical" radiation pattern. Omnidirectional antennas oriented vertically are widely used for nondirectional antennas on the surface of the Earth because they radiate equally in all horizontal directions, while the power radiated drops off with elevation angle so little radio energy is aimed into the sky or down toward the earth and wasted. Omnidirectional antennas are widely used for radio broadcasting antennas, and in mobile devices that use radio such as cell phones, FM radios, walkie-talkies, wireless computer networks, cordless phones, GPS as well as for base stations that communicate with mobile radios, such as police and taxi dispatchers and aircraft communications.
View Source: https://en.wikipedia.org/wiki/Omnidirectional_antenna
Pretty Good Privacy (PGP) is a data encryption and decryption computer program that provides cryptographic privacy and authentication for data communication. PGP is often used for signing, encrypting, and decrypting texts, e-mails, files, directories, and whole disk partitions and to increase the security of e-mail communications. PGP and similar software follow the OpenPGP standard for encrypting and decrypting data. OpenPGP's encryption can ensure secure delivery of files and messages, as well as provide verification of who created or sent the message using a process called digital signing. Using OpenPGP for communication requires participation by both the sender and recipient. OpenPGP can also be used to secure sensitive files when they're stored in vulnerable places like mobile devices or in the cloud.
View Source: https://en.wikipedia.org/wiki/Pretty_Good_Privacy#OpenPGP
A patch antenna (also known as a rectangular microstrip antenna) is a type of radio antenna with a low profile, which can be mounted on a flat surface. It consists of a flat rectangular sheet or "patch" of metal, mounted over a larger sheet of metal called a ground plane. The assembly is usually contained inside a plastic radome, which protects the antenna structure from damage. Patch antennas are simple to fabricate and easy to modify and customize. They are the original type of microstrip antenna described by Howell in 1972; the two metal sheets together form a resonant piece of microstrip transmission line with a length of approximately one-half wavelength of the radio waves. The radiation mechanism arises from discontinuities at each truncated edge of the microstrip transmission line. The radiation at the edges causes the antenna to act slightly larger electrically than its physical dimensions, so in order for the antenna to be resonant, a length of microstrip transmission line slightly shorter than one-half a wavelength at the frequency is used. A patch antenna is usually constructed on a dielectric substrate, using the same materials and lithography processes used to make printed circuit boards.
View Source: http://en.wikipedia.org/wiki/Patch_antenna
A private branch exchange (PBX) is a telephone exchange or switching system that serves a private organization and performs concentration of central office lines or trunks and provides intercommunication between a large number of telephone stations in the organization. The central office lines provide connections to the public switched telephone network and the concentration aspect of a PBX permits the shared use of these lines between all stations in the organization.
View Source: https://en.wikipedia.org/wiki/Business_telephone_system#Private_branch_exchange
Dilution of precision (DOP), or geometric dilution of precision (GDOP), is a term used in satellite navigation and geomatics engineering to specify the additional multiplicative effect of navigation satellite geometry on positional measurement precision. Due to the relative geometry of any given satellite to a receiver, the precision in the pseudorange of the satellite translates to a corresponding component in each of the four dimensions of position measured by the receiver (i.e., x, y, z, and t). The precision of multiple satellites in view of a receiver combine according to the relative position of the satellites to determine the level of precision in each dimension of the receiver measurement. When visible navigation satellites are close together in the sky, the geometry is said to be weak and the DOP value is high; when far apart, the geometry is strong and the DOP value is low. Consider two overlapping rings, or annuli, of different centres. If they overlap at right angles, the greatest extent of the overlap is much smaller than if they overlap in near parallel. Thus a low DOP value represents a better positional precision due to the wider angular separation between the satellites used to calculate a unit's position. Other factors that can increase the effective DOP are obstructions such as nearby mountains or buildings. DOP can be expressed as a number of separate measurements. HDOP, VDOP, PDOP, and TDOP are respectively Horizontal, Vertical, Position (3D), and Time Dilution of Precision.
View Source: https://en.wikipedia.org/wiki/Dilution_of_precision_(GPS)
A Personal Navigation Assistant (PNA) also known as Personal Navigation Device or Portable Navigation Device (PND) is a portable electronic product which combines a positioning capability (such as GPS) and navigation functions.
View Source: https://en.wikipedia.org/wiki/Personal_navigation_assistant
All J1939 packets, except for the request packet, contain eight bytes of data and a standard header which contains an index called Parameter Group Number (PGN), which is embedded in the message's 29-bit identifier. A PGN identifies a message's function and associated data. J1939 attempts to define standard PGNs to encompass a wide range of automotive, agricultural, marine and off-road vehicle purposes. A range of PGNs (00FF0016 through 00FFFF16, inclusive) is reserved for proprietary use. PGNs define the data which is made up of a variable number of Suspect Parameter Number (SPN) elements defined for unique data. For example, there exists a predefined SPN for engine RPM.
View Source: https://en.wikipedia.org/wiki/SAE_J1939#Definition
Programmable logic controller - A programmable logic controller, PLC, or programmable controller is a digital computer used for automation of typically industrial electromechanical processes, such as control of machinery on factory assembly lines, amusement rides, or light fixtures. PLCs are used in many machines, in many industries.
View Source: http://en.wikipedia.org/wiki/Programmable_logic_controller
Programmable logic controller - A programmable logic controller, PLC, or programmable controller is a digital computer used for automation of typically industrial electromechanical processes, such as control of machinery on factory assembly lines, amusement rides, or light fixtures. PLCs are used in many machines, in many industries. PLCs are designed for multiple arrangements of digital and analog inputs and outputs, extended temperature ranges, immunity to electrical noise, and resistance to vibration and impact. Programs to control machine operation are typically stored in battery-backed-up or non-volatile memory. A PLC is an example of a "hard" real-time system since output results must be produced in response to input conditions within a limited time, otherwise unintended operation will result.
View Source: https://en.wikipedia.org/wiki/Programmable_logic_controller
A Personal Navigation Assistant (PNA) also known as Personal Navigation Device or Portable Navigation Device (PND) is a portable electronic product which combines a positioning capability (such as GPS) and navigation functions.
View Source: https://en.wikipedia.org/wiki/Personal_navigation_assistant
A Personal Navigation Assistant (PNA) also known as Personal Navigation Device or Portable Navigation Device (PND) is a portable electronic product which combines a positioning capability (such as GPS) and navigation functions.
View Source: https://en.wikipedia.org/wiki/Personal_navigation_assistant
Power over Ethernet or PoE describes any of several standardized or ad-hoc systems which pass electrical power along with data on Ethernet cabling. This allows a single cable to provide both data connection and electrical power to devices such as wireless access points or IP cameras. Unlike standards such as Universal Serial Bus which also power devices over the data cables, PoE allows long cable lengths. Power may be carried on the same conductors as the data, or it may be carried on dedicated conductors in the same cable.
View Source: https://en.wikipedia.org/wiki/Power_over_Ethernet
Power over Ethernet or PoE describes any of several standardized or ad-hoc systems which pass electrical power along with data on Ethernet cabling. This allows a single cable to provide both data connection and electrical power to devices such as wireless access points or IP cameras. Unlike standards such as Universal Serial Bus which also power devices over the data cables, PoE allows long cable lengths. Power may be carried on the same conductors as the data, or it may be carried on dedicated conductors in the same cable.
View Source: https://en.wikipedia.org/wiki/Power_over_Ethernet
Plain old telephone service (POTS) is voice-grade telephone service employing analog signal transmission over copper loops. POTS was the standard service offering from telephone companies from 1876 until 1988 when the now-obsolete Integrated Services Digital Network (ISDN) Basic Rate Interface (BRI) was introduced, followed by cellular telephone systems, and Voice over IP (VoIP). POTS remains the basic form of residential and small business service connection to the telephone network in many parts of the world. The term reflects the technology that has been available since the introduction of the public telephone system in the late 19th century, in a form mostly unchanged despite the introduction of Touch-Tone dialing, electronic telephone exchanges and fiber-optic communication into the public switched telephone network (PSTN).
View Source: https://en.wikipedia.org/wiki/Plain_old_telephone_service
PPS signals are used for precise timekeeping and time measurement. Because GPS is considered a stratum-0 source, a common use for the PPS signal is to connect it to a PC using a low-latency, low-jitter wire connection and allow a program to synchronize to it. This makes the PC a stratum-1 time source. Note that because the PPS signal does not specify the time, but merely the start of a second, one must combine the PPS functionality with another time source that provides the full date and time in order to ascertain the time both accurately and precisely.
View Source: https://en.wikipedia.org/wiki/Pulse_per_second
Push-to-talk (PTT), also known as Press-to-Transmit, is a method of having conversations or talking on half-duplex communication lines, including two-way radio, using a momentary button to switch from voice reception mode to transmit mode.
View Source: https://en.wikipedia.org/wiki/Push-to-talk
Quality of service (QoS) is the overall performance of a telephony or computer network, particularly the performance seen by the users of the network.
View Source: https://en.wikipedia.org/wiki/Quality_of_service
Rain fade refers primarily to the absorption of a microwave radio frequency (RF) signal by atmospheric rain, snow or ice, and losses which are especially prevalent at frequencies above 11 GHz. It also refers to the degradation of a signal caused by the electromagnetic interference of the leading edge of a storm front.
View Source: https://en.wikipedia.org/wiki/Rain_fade
A rate of oscillation in the range of around 3 kHz to 300 GHz, which corresponds to the frequency of radio waves, and the alternating currents which carry radio signals. RF usually refers to electrical rather than mechanical oscillations; however, mechanical RF systems do exist. Although radio frequency is a rate of oscillation, the term "radio frequency" or its abbreviation "RF" are also used as a synonym for radio – i.e., to describe the use of wireless communication, as opposed to communication via electric wires.
View Source: http://en.wikipedia.org/wiki/Radio_frequency
Radio-frequency identification (RFID) is the wireless use of electromagnetic fields to transfer data, for the purposes of automatically identifying and tracking tags attached to objects. The tags contain electronically stored information. Some tags are powered by electromagnetic induction from magnetic fields produced near the reader. Some types collect energy from the interrogating radio waves and act as a passive transponder. Other types have a local power source such as a battery and may operate at hundreds of meters from the reader. Unlike a barcode, the tag does not necessarily need to be within line of sight of the reader and may be embedded in the tracked object.
View Source: https://en.wikipedia.org/wiki/Radio-frequency_identification
Right Hand Circular Polarization - Circular polarization is commonly used in satellite communications where the orientation of the satellite and the receiver cannot be linearly aligned. The circular polarization of an electromagnetic wave is a polarization in which the electric field of the passing wave does not change strength but only changes direction in a rotary manner.
View Source: http://en.wikipedia.org/wiki/Circular_polarization
In telecommunications, RS-232 is a standard for serial communication transmission of data. It formally defines the signals connecting between a DTE (data terminal equipment) such as a computer terminal, and a DCE (data circuit-terminating equipment, originally defined as data communication equipment), such as a modem. The RS-232 standard is commonly used in computer serial ports. The standard defines the electrical characteristics and timing of signals, the meaning of signals, and the physical size and pinout of connectors. The current version of the standard is TIA-232-F Interface Between Data Terminal Equipment and Data Circuit-Terminating Equipment Employing Serial Binary Data Interchange, issued in 1997.
View Source: http://en.wikipedia.org/wiki/RS-232
TIA-485-A, also known as ANSI/TIA/EIA-485, TIA/EIA-485, EIA-485 or RS-485, is a standard defining the electrical characteristics of drivers and receivers for use in balanced digital multipoint systems.
View Source: https://en.wikipedia.org/wiki/RS-485
In telecommunications, received signal strength indicator (RSSI) is a measurement of the power present in a received radio signal. RSSI is usually invisible to a user of a receiving device. However, because signal strength can vary greatly and impact functionality in wireless networking, IEEE 802.11 devices often make the measure available to users. RSSI is often done in the intermediate frequency (IF) stage before the IF amplifier. In zero-IF systems, it is done in the baseband signal chain, before the baseband amplifier. RSSI output is often a DC analog level. It can also be sampled by an internal ADC and the resulting codes available directly or via peripheral or internal processor bus.
View Source: https://en.wikipedia.org/wiki/Received_signal_strength_indication
The Iridium Router-Based Unrestricted Digital Internetworking Connectivity Solutions (RUDICS) is an enhanced data service that allows customers who have requirements for large data transfers the ability to transfer data via reliable, affordable, multi-protocol Mobile Originated (MO) and Mobile Terminated (MT) circuit switched data connectivity across the Iridium satellite network.
View Source: https://www.iridium.com/products/RUDICS.aspx
The S band is part of the microwave band of the electromagnetic spectrum. It is defined by an IEEE standard for radio waves with frequencies that range from 2 to 4 GHz, crossing the conventional boundary between UHF and SHF at 3.0 GHz. The S band is used by weather radar, surface ship radar, and some communications satellites, especially those used by NASA to communicate with the Space Shuttle and the International Space Station. The 10-cm radar short-band ranges roughly from 1.55 to 5.2 GHz.
View Source: https://en.wikipedia.org/wiki/S_band
SAE J1708 is a standard used for serial communications between ECUs on a heavy duty vehicle and also between a computer and the vehicle. With respect to Open System Interconnection model (OSI), J1708 defines the physical layer. Common higher layer protocols that operate on top of J1708 are SAE J1587 and SAE J1922. The protocol is maintained by SAE International.
View Source: https://en.wikipedia.org/wiki/SAE_J1708
SAE J1939 is the vehicle bus recommended practice used for communication and diagnostics among vehicle components. Originating in the car and heavy-duty truck industry in the United States, it is now widely used in other parts of the world. SAE J1939 is used in the commercial vehicle area for communication throughout the vehicle, with the physical layer defined in ISO 11898. A different physical layer is used between the tractor and trailer, specified in ISO 11992.
View Source: https://en.wikipedia.org/wiki/SAE_J1939
SAE standards documents on OBD-II: J1979 – Defines standards for diagnostic test modes
View Source: https://en.wikipedia.org/wiki/On-board_diagnostics#SAE_standards_documents_on_OBD-II
Satellite-based augmentation system (SBAS) is a system that supports wide-area or regional augmentation to improve the navigation system's attributes, such as accuracy, reliability, and availability through the use of additional satellite-broadcast messages. Such systems are commonly composed of multiple ground stations, located at accurately-surveyed points. The ground stations take measurements of one or more of the GNSS satellites, the satellite signals, or other environmental factors which may impact the signal received by the users. Using these measurements, information messages are created and sent to one or more satellites for broadcast to the end users.
View Source: https://en.wikipedia.org/wiki/GNSS_augmentation
Short burst data - Special modems such as the 9522A, 9601, 9602 and Quake Q9612 can be used for sending and receiving short data bursts, less than 2 kilobytes at a time. This service is often used for asset tracking and remote monitoring. Messages are converted to be delivered in email format or over HTTP to a preconfigured address; the mobile unit does not include a destination address when sending a SBD message. A crude positioning report is also included in each message sent. SBD messages take from 6 to 22 seconds to send or receive. The latest generation of SBD transceiver, the Iridium 9602, can receive up to 270 bytes per SBD data message (defined by Iridium as "mobile terminated SBD") and can transmit a maximum of 340 bytes per SBD message (defined by Iridium as "mobile originated SBD"). A real-world example of the 9602 chipset in use is the YB Tracker.
View Source: https://iridium.com/products/IridiumSBD.aspx
SCADA (supervisory control and data acquisition) is a system operating with coded signals over communication channels so as to provide control of remote equipment (using typically one communication channel per remote station). The control system may be combined with a data acquisition system by adding the use of coded signals over communication channels to acquire information about the status of the remote equipment for display or for recording functions. It is a type of industrial control system (ICS). Industrial control systems are computer-based systems that monitor and control industrial processes that exist in the physical world. SCADA systems historically distinguish themselves from other ICS systems by being large-scale processes that can include multiple sites, and large distances.
View Source: http://en.wikipedia.org/wiki/SCADA
A software development kit (SDK or "devkit") is typically a set of software development tools that allows the creation of applications for a certain software package, software framework, hardware platform, computer system, video game console, operating system, or similar development platform.
View Source: https://en.wikipedia.org/wiki/Software_development_kit
Super high frequency (SHF) is the ITU designation for radio frequencies (RF) in the range between 3 GHz and 30 GHz. This band of frequencies is also known as the centimetre band or centimetre wave as the wavelengths range from one to ten centimetres. These frequencies fall within the microwave band, so radio waves with these frequencies are called microwaves. The small wavelength of microwaves allows them to be directed in narrow beams by aperture antennas such as parabolic dishes, so they are used for point-to-point communication and data links and for radar. This frequency range is used for most radar transmitters, microwave ovens, wireless LANs, cell phones, satellite communication, microwave radio relay links, and numerous short range terrestrial data links. Wireless USB technology is anticipated to use approximately one-third of this spectrum.
View Source: https://en.wikipedia.org/wiki/Super_high_frequency
Short burst data - Special modems such as the 9522A, 9601, 9602 and Quake Q9612 can be used for sending and receiving short data bursts, less than 2 kilobytes at a time. This service is often used for asset tracking and remote monitoring. Messages are converted to be delivered in email format or over HTTP to a preconfigured address; the mobile unit does not include a destination address when sending a SBD message. A crude positioning report is also included in each message sent. SBD messages take from 6 to 22 seconds to send or receive. The latest generation of SBD transceiver, the Iridium 9602, can receive up to 270 bytes per SBD data message (defined by Iridium as "mobile terminated SBD") and can transmit a maximum of 340 bytes per SBD message (defined by Iridium as "mobile originated SBD"). A real-world example of the 9602 chipset in use is the YB Tracker.
View Source: https://iridium.com/products/IridiumSBD.aspx
A subscriber identity module or subscriber identification module (SIM) is an integrated circuit that is intended to securely store the international mobile subscriber identity (IMSI) and the related key used to identify and authenticate subscribers on mobile telephony devices (such as mobile phones and computers). SIM cards are designed to be transferrable between different mobile devices. A SIM card contains its unique serial number (ICCID), international mobile subscriber identity (IMSI), security authentication and ciphering information, temporary information related to the local network, a list of the services the user has access to and two passwords: a personal identification number (PIN) for ordinary use and a personal unblocking code (PUK) for PIN unlocking.
View Source: https://en.wikipedia.org/wiki/Subscriber_identity_module
The Session Initiation Protocol (SIP) is a communications protocol for signaling and controlling multimedia communication sessions. The most common applications of SIP are in Internet telephony for voice and video calls, as well as instant messaging all over Internet Protocol (IP) networks.
View Source: https://en.wikipedia.org/wiki/Session_Initiation_Protocol
SiRFstarV chips are capable of tracking NAVSTAR, GLONASS, Galileo, Compass, SBAS, and future GNSS signals. The SiRFusion platform integrates positioning from GNSS, terrestrial radio solutions such as Wi-Fi and cellular, and MEMS sensors including accelerometers, gyroscopes, and compasses. SiRFusion can then combine this real-time information with cellular base station and Wi-Fi access point location data, ephemeribased aiding information from the CSR Positioning Center (CPC) to generate accurate and reliable position updates.
View Source: https://en.wikipedia.org/wiki/SiRF
SMA (SubMiniature version A) connectors are semi-precision coaxial RF connectors developed in the 1960s as a minimal connector interface for coaxial cable with a screw type coupling mechanism. The connector has a 50 Ω impedance. It is designed for use from DC to 18 GHz.
View Source: https://en.wikipedia.org/wiki/SMA_connector
Short Message Service (SMS) is a text messaging service component of phone, Web, or mobile communication systems. It uses standardized communications protocols to allow fixed line or mobile phone devices to exchange short text messages.
View Source: https://en.wikipedia.org/wiki/Short_Message_Service
Signal-to-noise ratio (abbreviated SNR or S/N) is a measure used in science and engineering that compares the level of a desired signal to the level of background noise. It is defined as the ratio of signal power to the noise power, often expressed in decibels. A ratio higher than 1:1 (greater than 0 dB) indicates more signal than noise. While SNR is commonly quoted for electrical signals, it can be applied to any form of signal (such as isotope levels in an ice core or biochemical signaling between cells).
View Source: https://en.wikipedia.org/wiki/Signal-to-noise_ratio
A Spatial Reference System Identifier (SRID) is a unique value used to unambiguously identify projected, unprojected, and local spatial coordinate system definitions. These coordinate systems form the heart of all GIS applications. Virtually all major spatial vendors have created their own SRID implementation or refer to those of an authority, such as the European Petroleum Survey Group (EPSG).
View Source: https://en.wikipedia.org/wiki/SRID
The Ship Security Alert System (SSAS) is part of the ISPS code and is a system that contributes to the International Maritime Organization's (IMO)'s efforts to strengthen maritime security and suppress acts of terrorism and piracy against shipping. The system is a IMO regulated system. In case of attempted piracy or terrorism, the ship's SSAS beacon can be activated, and appropriate law-enforcement or military forces can be dispatched. An SSAS beacon operates with similar principles to the aircraft transponder emergency code 7700.
View Source: https://en.wikipedia.org/wiki/Ship_Security_Alert_System
Secure Sockets Layer. It provides a secure connection between internet browsers and websites, allowing you to transmit private data online. Sites secured with SSL display a padlock in the browsers URL and possibly a green address bar if secured by an EV Certificate.
View Source: http://info.ssl.com/article.aspx?id=10241
Dilution of precision (DOP), or geometric dilution of precision (GDOP), is a term used in satellite navigation and geomatics engineering to specify the additional multiplicative effect of navigation satellite geometry on positional measurement precision. Due to the relative geometry of any given satellite to a receiver, the precision in the pseudorange of the satellite translates to a corresponding component in each of the four dimensions of position measured by the receiver (i.e., x, y, z, and t). The precision of multiple satellites in view of a receiver combine according to the relative position of the satellites to determine the level of precision in each dimension of the receiver measurement. When visible navigation satellites are close together in the sky, the geometry is said to be weak and the DOP value is high; when far apart, the geometry is strong and the DOP value is low. Consider two overlapping rings, or annuli, of different centres. If they overlap at right angles, the greatest extent of the overlap is much smaller than if they overlap in near parallel. Thus a low DOP value represents a better positional precision due to the wider angular separation between the satellites used to calculate a unit's position. Other factors that can increase the effective DOP are obstructions such as nearby mountains or buildings. DOP can be expressed as a number of separate measurements. HDOP, VDOP, PDOP, and TDOP are respectively Horizontal, Vertical, Position (3D), and Time Dilution of Precision.
View Source: https://en.wikipedia.org/wiki/Dilution_of_precision_(GPS)
A timestamp is a sequence of characters or encoded information identifying when a certain event occurred, usually giving date and time of day, sometimes accurate to a small fraction of a second.
View Source: https://en.wikipedia.org/wiki/Timestamp
The TNC (Threaded Neill–Concelman) connector is a threaded version of the BNC connector. The connector has a 50 Ω impedance and operates best in the 0–11 GHz frequency spectrum.
View Source: https://en.wikipedia.org/wiki/TNC_connector
A communications satellite’s channels are called transponders, because each is a separate transceiver or repeater.
View Source: https://en.wikipedia.org/wiki/Transponder
The Universal Serial Bus (USB) is technology that allows a person to connect an electronic device to a computer. It is a fast serial bus.
View Source: https://simple.wikipedia.org/wiki/Universal_Serial_Bus
USB communications device class (or USB CDC) is a composite Universal Serial Bus device class. The class may include more than one interface, such as a custom control interface, data interface, audio, or mass storage related interfaces.
View Source: https://en.wikipedia.org/wiki/USB_communications_device_class
USB communications device class (or USB CDC) is a composite Universal Serial Bus device class. The class may include more than one interface, such as a custom control interface, data interface, audio, or mass storage related interfaces.
View Source: https://en.wikipedia.org/wiki/USB_communications_device_class
Dilution of precision (DOP), or geometric dilution of precision (GDOP), is a term used in satellite navigation and geomatics engineering to specify the additional multiplicative effect of navigation satellite geometry on positional measurement precision. Due to the relative geometry of any given satellite to a receiver, the precision in the pseudorange of the satellite translates to a corresponding component in each of the four dimensions of position measured by the receiver (i.e., x, y, z, and t). The precision of multiple satellites in view of a receiver combine according to the relative position of the satellites to determine the level of precision in each dimension of the receiver measurement. When visible navigation satellites are close together in the sky, the geometry is said to be weak and the DOP value is high; when far apart, the geometry is strong and the DOP value is low. Consider two overlapping rings, or annuli, of different centres. If they overlap at right angles, the greatest extent of the overlap is much smaller than if they overlap in near parallel. Thus a low DOP value represents a better positional precision due to the wider angular separation between the satellites used to calculate a unit's position. Other factors that can increase the effective DOP are obstructions such as nearby mountains or buildings. DOP can be expressed as a number of separate measurements. HDOP, VDOP, PDOP, and TDOP are respectively Horizontal, Vertical, Position (3D), and Time Dilution of Precision.
View Source: https://en.wikipedia.org/wiki/Dilution_of_precision_(GPS)
Voice over IP (VoIP) is a methodology and group of technologies for the delivery of voice communications and multimedia sessions over Internet Protocol (IP) networks, such as the Internet.
View Source: http://en.wikipedia.org/wiki/Voice_over_IP
A very small aperture terminal (VSAT) is a two-way satellite ground station or a stabilized maritime VSAT antenna with a dish antenna that is smaller than 3 meters.
View Source: https://en.wikipedia.org/wiki/Very-small-aperture_terminal
The W band of the microwave part of the electromagnetic spectrum ranges from 75 to 110 GHz, wavelength ~2.7-4 mm. It sits above the U.S. IEEE-designated V band (50–75 GHz) in frequency, and overlaps the NATO designated M band (60–100 GHz). The W band is used for satellite communications, millimeter-wave radar research, military radar targeting and tracking applications, and some non-military applications.
View Source: https://en.wikipedia.org/wiki/W_band
A waypoint is a reference point in physical space used for purposes of navigation, otherwise known as a landmark.
View Source: https://en.wikipedia.org/wiki/Waypoint
Web Mercator, Google Web Mercator, Spherical Mercator, WGS 84 Web Mercator, Spherical Mercator, WGS 84 Web Mercator or WGS 84/Pseudo-Mercator is a variation of the Mercator projection and is the de facto standard for Web mapping applications. It rose to prominence when used in the first Google Maps in 2005. It is used by virtually all major online map providers, including Google Maps, Bing Maps, Mapquest, Mapbox, OpenStreetMap and many others.
View Source: https://en.wikipedia.org/wiki/Web_Mercator
Wireless sensor networks (WSN), sometimes called wireless sensor and actuator networks (WSAN), are spatially distributed autonomous sensors to monitor physical or environmental conditions, such as temperature, sound, pressure, etc. and to cooperatively pass their data through the network to a main location. The more modern networks are bi-directional, also enabling control of sensor activity. The development of wireless sensor networks was motivated by military applications such as battlefield surveillance; today such networks are used in many industrial and consumer applications, such as industrial process monitoring and control, machine health monitoring, and so on.
View Source: https://en.wikipedia.org/wiki/Wireless_sensor_network
The X band is a segment of the microwave radio region of the electromagnetic spectrum. In some cases, such as in communication engineering, the frequency range of the X band is rather indefinitely set at approximately 7.0 to 11.2 gigahertz (GHz). In radar engineering, the frequency range is specified by the IEEE at 8.0 to 12.0 GHz.
View Source: https://en.wikipedia.org/wiki/X_band
ZigBee is a specification for a suite of high-level communication protocols used to create personal area networks built from small, low-power digital radios. ZigBee is based on an IEEE 802.15.4 standard. Though its low power consumption limits transmission distances to 10–100 meters line-of-sight, depending on power output and environmental characteristics, ZigBee devices can transmit data over long distances by passing data through a mesh network of intermediate devices to reach more distant ones. ZigBee is typically used in low data rate applications that require long battery life and secure networking (ZigBee networks are secured by 128 bit symmetric encryption keys.) ZigBee has a defined rate of 250 kbit/s, best suited for intermittent data transmissions from a sensor or input device. Applications include wireless light switches, electrical meters with in-home-displays, traffic management systems, and other consumer and industrial equipment that requires short-range low-rate wireless data transfer. The technology defined by the ZigBee specification is intended to be simpler and less expensive than other wireless personal area networks (WPANs), such as Bluetooth or Wi-Fi.
View Source: http://en.wikipedia.org/wiki/ZigBee
