• A/D -

    Aerospace and Defense is an industry of military contract companies or commercial companies or both. These companies produce defense products (missiles, aircraft, electronics) or commercial products such as satellites or timing devices.

  • Accelerometer -

    Accelerometer measures the acceleration it experiences.

    See also

  • ACES -

    Atomic Clock Ensemble In Space is a European Space Agency program aimed at studying the fundamental laws of physics. With the goal of precision scientific experiments, ACES uses the microgravity environment of the international space station to test sub atomic clocks.

  • ADG -

    Aerospace, Defense & Government refers to an entire industry of governmental agencies that focus on technology and defense for the United States government. It is a broad term that encompasses governmental entities that use specialized technology for aviation and space applications, especially applications relating to national security and classified operations.

  • AHRS -

    Attitude Heading Reference System. 3-axis sensors that provide heading, attitude and yaw information for aircraft. Replaces traditional mechanical gyroscopic flight instruments.

    See also

  • AIS AtoN -

    AIS and AtoN systems gather and distribute navigational data to other vehicles using the same systems. Aids-To-Navigation units are used either as a radio emitter or a radio transponder to help provide extra navigational data especially for ships and sea vessels. They help to alert vessels of off-shore hazards, or other obstructions such as oil rigs or wind farms. The AtoN systems are usually placed on floating buoys.

  • AMSA -

    AMSA is an Australian national regulatory body that promotes the safety and protection of Australia's marine environment. They also provide technology and equipment for safe navigation in Australian waters, as well as a search and rescue service.

  • Anodic Wafer Bonding -

    Silicon and glass substrates are bonded at elevated temperature and with a high DC potential creating an electrical field. Sodium ions between the substrate surfaces are forming a solid chemical bond.

  • ANSP -

    An ANSP is the type of organization that provides air traffic control services for a specific region of airspace. Either public or private, an ANSP can represent a company or a country to provide the organizational and navigational services of air traffic control.

  • Atomic Clock -

    A clock that uses vibrations of a molecular or atomic system, rather than mechanical systems, to keep time. They are the most exact—and most expensive—clocks available.

  • BiCMOS -

    Bipolar junction transistors and Metal-Oxide-Semiconductor technology into a single device.

    See also

  • C2 -

    Command and Control is a military system that consists of a properly designated commander who exercises authority over assigned resources in the accomplishment of a common goal.

  • C4I -

    Command Control Communications Computers and Intelligence is a military system that comprises of communication equipment and networks that help to provide situational awareness in the battlefield.

  • C4ISR -

    A military system that encompasses the technology and equipment to collect data and communicate with other parts of the system. C4ISR is designed to provide situational awareness on the battlefield.

  • C5ISR -

    A military system that encompasses the technology and equipment to command, control, computers, communications, cyber-defense for intelligence, surveillance, and reconnaissance. C5ISR is designed to provide resilient situational awareness on the battlefield.

  • CAAS -

    The Civil Aviation Authority Singapore is a Statutory Board in Singapore that provides air navigation services and promotes Singapore as a center of excellence for aviation knowledge.

  • CNES -

    CNES is the French Government Space Agency.

  • CROSS -

    CROSS is the french departmental agency that provides search and rescue services.

  • CS -

    Cesium is one of the elements on the periodic table that has an atomic number of 55 and is liquid at room temperature. The cesium non radioactive isotope 133 is used in some of the world's most precise atomic clocks. Fundamental international standard for weights and measures defines that frequency of electromagnetic emission and absorption between unperturbed ground-state of two hyperfine states of this atom is 9 192 631 770 when expressed in the unit Hz, which is equal to s–1.

  • CSAR -

    Combat Search and Rescue entails the technology that allows individuals to request help and get rescued by using encrypted signals without the enemy being able to locate them. CSAR personal locator beacons are able to send signals for a search and rescue operation when in a contested environment.

  • CSS -

    A Coastal Surveillance System is an intricate network of radar, electro-optical sensors, and automatic identification systems to provide command and control functions. It is primarily used by countries as a way to monitor territorial border areas.

  • DASS -

    A distress Alerting Satellite System is a satellite-aided search and rescue system that is dedicated to detecting and locating emergency locator beacons activated by persons, aircraft or vessels in distress.

  • DCA -

    The Department of Civil Aviation is a regulatory body of civil aviation located in the channel islands of Guernsey. It is responsible for ensuring the safety of civil aviation around Guernsey and its airspace.

  • Dopper Solution -

    Doppler radar is a type of radar that measures velocity data of moving objects at a distance. It achieves this measurement by sending a microwave signal to the desired target, the signal bounces off the target, and then the radar analyzes how the target's motion has altered the frequency of the returned signal.

  • DoT -

    The United States Department of Transportation is departmental agency that is part of the federal government. It is responsible for the planning and coordination of transportation projects and the construction of infrastructure such as roads, highways and bridges.

  • ELT -

    An Emergency Location Transmitter is a small device that transmits radio signals to search and rescue teams in case there is a crash or emergency. The signals are used by search and rescue teams to locate the vehicle and rescue the crew.

  • EMCON -

    Emissions Control is a military concealment tactic to prevent an enemy from locating friendly forces. There are different levels of prevention that all deal with turning off the transmission signals emitting from radios.

  • EMI -

    Short for Electro-Magnetic Interference. EMI shielding is a necessary feature of many electronic devices which are often interrupted by external electromagnetic signals, such as rubidium oscillators.

  • EPIRB -

    An Emergency Position Indicating Radio Beacon is a type of emergency locator beacon that can transmit radio signals during an emergency situation. Usually portable and battery-powered EPIRBs are used to help search and rescue teams locate an aircraft or vessel that is in need of immediate rescue.

  • Epitaxial Layer -

    Method of depositing a monocrystalline film on a monocrystalline substrate.

    See also

  • ESA -

    The European Space Agency is a group of countries in Europe and Canada dedicated to the exploration of space as well as other scientific space missions. As of 2022 there are 22 member states that make up this intergovernmental organization.

  • ESOC -

    The European Space Operations Centre is the main mission control room that monitors and controls missions for the ESA (European Space Agency). While the headquarters of the ESA is in Paris, France, the main mission control center that is responsible for overseeing all space mission operations is located in Darmstadt, Germany.

  • EWG -

    The Experts Working Group for COSPAS-SARSAT is an advisory board designed to oversee the COSPAS-SARSAT system and its longevity.

  • FAA -

    The Federal Aviation Administration is the regulatory transportation agency in the Unites States responsible for regulating all aspects of civil aviation in the US.

  • Failure Rate -

    The frequency with which a component fails.

    See also

  • FF210 -

    The FastFind 210 PLB is a highly accurate and responsive personal locator beacon. It meets the rigorous testing standards of COSPAS-SARSAT, FCC, and NOAA and should only be used in situations of grave and imminent danger.

  • Field Failure -

    Failure occurred during normal operation by end user.

  • FOC -

    Full Operational Capability refers to military acquisition missions that have been completed the development phase. This phase comes after an initial operational capability phase.

  • FOG -

    Fiber Optic Gyroscope. Uses the interference of light to detect mechanical rotation.

    See also

  • FPGA -

    Field-Programming Gate Array: an integrated circuit designed to be configured by a customer or a designer after manufacturing – hence the term field-programmable.

    See also

  • GADSS -

    The Global Aeronautical Distress and Safety System is an aircraft tracking technology that is responsible for tracking the location and status of the aircraft throughout all phases flight. GADSS main functions are: aircraft tracking, autonomous distress tracking, post flight localization and recovery.

  • GEO -

    Geostationary Earth Orbit is a circular orbit trajectory that is geosynchronous with Earth's rotational movement. Because it matches Earth's rotation, a satellite in a geostationary orbit appears to be stationary to an observer on the ground.

  • Gimbal -

    Pivoted support that allows the rotation of an object about a single axis.

    See also

  • GNSS -

    Global navigation satellite system (GNSS): A general term describing any satellite constellation that provides positioning, navigation, and timing (PNT) services on a global or regional basis.

    See also

  • GNSS Antenna -

    Device which receives and then amplifies specific radio frequencies from GNSS satellites, ultimately converting them into electronic signals to be received by GNSS or GPS receivers.

  • GPS -

    Global Positioning System is a navigation satellite system.

    See also

  • GPS Receiver -

    Collects and converts GPS satellite signals from a GNSS antenna, translating them into usable data.

  • GPS Time -

    GPS Time (GPST) is an ongoing time scale, set by the GPS Control segment based on atomic clocks which are onboard satellites and present at Monitor Stations.

  • GPS/GNSS Clock -

    Based on atomic clock technology, a GPS or GNSS clock uses GPS satellite timing to give users extremely precise timing information.

  • GSG -

    A GNSS Signal Generator is a device that is able to create simulated satellite signals and generate real RF signals by first producing I/Q data and calculating the orbits of satellites at a user-defined time, location and trajectory.

  • Gyro -

    Device for measuring or maintaining orientation, based on the principles of angular momentum.

    See also

  • H2020 -

    European Union global Research and Innovation programme covering 2014-2020 period. Horizon Europe is the following programme covering 2021-2027. New RLS capable Search and Rescue Beacons has been developed with H2020 support.


    HANSCOM is a US Military Program associated with SAASM timer servers for military communication networks (US Air Force).

  • HAWK II -

    R&D project with the aim of fixing major obsolescence issues with legacy search and rescue beacons and personal locator beacons.

  • HFT -

    HFT stands for High Frequency Trading and is used in the banking and finance industry, especially for big banks and international corporations.

  • HG -

    HG is the periodic element for Mercury.

  • HPC -

    High Performance Computing is an emerging field in computer engineering that usually entails clusters of powerful computers linked together to solve a complex problem. High performance computing is used for scientific discoveries, research, AI, the Internet of Things, and 3D image processing.

  • IMU -

    An IMU or Inertial Measurement Unit is an electronic device that measures the heading and orientation and velocity of a vehicle. It contains both an accelerometer and a gyroscope to provide necessary data to maneuver an aircraft or spacecraft, especially when GPS signals are not available.

  • Inertia -

    The resistance of mass, i.e. any physical object, to a change in its state of motion.

    See also

  • INS -

    An INS or Inertial Navigation System - sometimes used synonomously with IMU is a device used to measure a vehicle's speed, position, velocity, heading and orientation by using an accelerometer and a gyroscope.

  • IRNSS -

    IRNSS is the Indian Regional Navigational Satellite System. Similar to the concept of GNSS - or Global Navigation Satellite System, the IRNSS is a group of satellites that provides location services for a smaller region of the world, around India and 930 miles outside of India.

  • JAXA -

    JAXA refers to the Japanese Aerospace Exploration Agency which is responsible for the exploration and coordination of space missions launching from Japan.

  • LEO -

    LEO - Low Earth Orbit. LEO refers to the orbit that most artificial satellites travel within. LEO is closer to earth compared to other satellite constellations such as GPS and GEO satellite systems. LEO is approximately 1,200 miles above Earth or less, meaning the satellites in this orbit travel at high speeds (i.e. 15,000 mph) and can orbit the Earth in less than 2 hours. Most human spaceflight missions have ocurred within LEO.

  • LEO Satellite -

    Short for Low Earth Orbit satellite; typically an electronic device or equipment which orbits between 200 and 2,000 kilometers above the earth. Circles at a lower altitude than geosynchronous satellites.

  • LF Wireless -

    Wireless transmission at Low Frequency in the range of 30kHz-300kHz.

    See also

  • LNMO -

    A Low Noise Master Oscillator 10 MHz is a device able to provide up to two 10 MHz outputs with very low phase noise in order to operate as a stable RF reference. This signal is distributed along the particle accelerator and used as synchronization master reference for all the machine subsystems.

  • LUT -

    A LUT, or Local User Terminal are the ground station segments of the COSPAS-SARSAT system. The LUTs receive signals from satellites and then calculate the location of distress calls emanating from emergency beacons. Once the information is received from the satellites, the LUT then takes that information and sends it to the MCC or mission control center that operates that LUT. The MCC can then dispatch a search and rescue team to locate and track down the people at the location of the emergency locator beacon.

  • MCC -

    A Mission Control Center is part of the ground segment of the COSPAS-SARSAT system. Operators working at the MCC will be notified of any distress signals because they will receive it from the LUTs (Local User Terminals) which received signals from the satellites. The MCC is then able to dispatch a search and rescue team to aid the people at the location of the emergency locator beacon.

  • Meaconing -

    Meaconing is a system of receiving radio beacon signals from NAVAIDs and rebroadcasting them on the same frequency to confuse navigation. The enemy conducts meaconing operations against us to prevent our aircraft and ships from arriving at their intended targets or destinations.

  • MEMS -

    MicroElectroMechanical System.

    See also

  • MEO Satellite -

    Short for Medium Earth Orbit satellite; typically an electronic device or equipment which orbits between 5,000 and 12,000 kilometers above the earth. Circles at a lower altitude than geosynchronous satellites.

  • MEOLUT -

    A MEOLUT (Medium Earth Orbit Local User Terminal) is a LUT that supports the medium earth orbit group of satellites that provide search and rescue location signals and services.

  • MEOSAR -

    Medium Altitude Earth Orbit Search and Rescue system, is a system of satellites, ground stations and mission control centers that can identify distress signals sent from emergency beacons and send help to their location. These MEO satellites orbit the Earth at an altitude between 19,000 and 24,000 km above the earth.

  • Microcontroller -

    Small computer on a single integrated circuit designed for small applications.

    See also

  • MODE S -

    MODE S is an air traffic control data link technology.

  • NASA -

    National Aeronautics and Space Agency - responsible for the policy, strategy and operations of US space missions.

  • NAVWAR -

    Navigational Warfare

    See also

  • NOAA -

    The National Oceanic and Atmospheric Administration is an agency of the US federal government responsible for shaping policy around oceanic use, climate, and weather. NOAA collects weather data as well as conducts extensive scientific research to provide citizens, planners, and other decision makers with reliable information and data.

  • NTP -

    NTP, or Network Time Protocol, is a widely used networking protocol that enables computers and devices to synchronize their system clocks with a reference time source. It ensures accurate timekeeping in computer networks by allowing devices to obtain precise time information from NTP servers, which are typically synchronized to highly accurate atomic clocks. NTP is essential for various applications and services that rely on synchronized time, such as network security, authentication, and data logging.

  • Numerically Controlled Oscillator (NCO) -

    Generator of digital signals, creates a synchronized circuit representation of signals it receives.

  • PFM -

    Proto Flight Model is a phase during a staged development process when aerospace engineers will take a prototype of a space vehicle or prototype of an aircraft and fly it to test its functionality.

  • PHM -

    A PHM or Passive Hydrogen Maser is an atomic clock designed to sit onboard space vehichles and satellites which is then used for ultra accurate timekeeping and positioning.

  • PLB -

    Personal Locator Beacon is a handheld device that can be used by individuals in remote areas in need of emergency services or rescue. A PLB will send a signal to the SARSAT satellites which then send that distress signal down back to Earth to the LUTs (Local User Terminals) which then send that information to an MCC (Mission Control Center) which can then dispatch search and rescue services to the location of the PLB.

  • PMAW -

    The Product Management Air Warrior office is a military entity that is responsible for developing and fielding equipment that improves the survivability of Army aircrews.

  • PNT -

    Position, Navigation, and Timing: PNT and map data combine to create the GPS service.

  • PTP -

    Precision Time Protocol is a protocol used to synchronize clocks throughout a computer network. On a LAN network, PTP can enable the clocks on each server to be synchronized within a sub-microsecond range, thus making it suitable for demanding applications that require precise timing and control. PTP is standardized within IEEE-1588v2.

  • Q Factor -

    Describes how under-damped an oscillator is. In electronic engineering, as a measure of the 'quality' in a well tuned circuit or resonator.

    See also

  • QZSS -

    QZSS is a regional satellite system in the Asia/Pacific Region. Developed and maintained by the Japanese government, this satellite constellation provides similar services as GPS: location, navigation and timing.

  • RAFS -

    The Rubidium Atomic Frequency Standard is 10.00 MHz which is a space-qualified frequency standard by which all atomic clocks are measured by. The 10.00 MHz frequency is derived by the spectral absorption line of the Rb87 isotope.

  • Rb -

    Rb - Rubidium is a rare, surprisingly soft whitish-grey metal. It is used in ultra precise atomic clocks to make oscillators.

  • RDF -

    Radio Detection Finding is the process of using multiple antennas receiving radio wave information to determine the direction of the emitting signal and an object's location.

  • RISC -

    Reduced Instruction Set Computer. ARM RISC - Advanced RISC Machine.

    See also

  • RLG -

    Ring Laser Gyroscope. Uses interference of laser light within an optical ring to detect changes in orientation and spin.

    See also

  • RLS Beacon -

    A beacon with an integrated GALILEO receiver enabled to receive an RLM (Return Link Message).

  • ROV -

    Remotely Operated Vehicle. Underwater robot common in deepwater industries such as offshore hydrocarbon extraction.

    See also

  • RS422 Protocol -

    Technical standard defining Electrical Characteristics of Balanced Voltage Differential Interface Circuits.

    See also

  • SAR -

    Search and Rescue

  • SARSAT -

    Search and Rescue Using Satellite Aided Technology is a network of satellites, control centers, and response facilities designed to provide search and rescue services all around the globe. SARSAT uses a specific frequency band to identify and locate distress signals, as well as emergency locator beacons that individuals can use or be placed in a vehicle. PLBs or personal locator beacons as well as ELTs in aircraft are activated in emergency situations.

  • SART -

    A SART - Search and Rescue Transponder - is a type of radio signal receiver that is installed inside a SARSAT satellite which can recognize and repeat a distress signal sent from an emergency locator beacon or personal locator beacon.

  • SAS-E -

    Signal Amplifer and Switch With Ethernet Interface


    SIMULCAST - The process of emitting the same signal from different radio towers that both use the exact same frequency and the exact same time. The towers need to be synchronized in order to transmit the signal without interference.

  • SOIC Package -

    Small-Outline Integrated Circuit. Surface-mounted integrated circuit (IC) package.

    See also

  • SPI Communication -

    Serial Peripheral Interface bus. Synchronous serial data link standard that operates in full duplex mode.

    See also

  • SPOT -

    SPOT Messenger GlobalStar Satellite Messenger - is a pocketsized safety device that can be used to transmit your GPS coordinates to emergency responders in times of need.

  • SSO -

    SSO refers to the Swiss Space Office. The SSO is responsible for overseeing all policy and strategy surrounding Space operations for Switzerland.

  • SyncE -

    SyncE - Synchronous Ethernet is a networking protocol that sends IP packets in a synchronous way from one node to another. This allows data and signals to be sent synchronously in IP networks. This solves the synchronization issue in networks, because without SyncE, networks are completely asynchronous and cannot send packets in a predictable way.

  • T&M -

    T&M stands for Test and Measurement.

  • Tactical Grade IMU -

    A tactical grade IMU can be used to provide stand-alone navigation for a few minutes. Tactical grade IMU's are used extensively in the industry and defense sector due to their cost effective performance. Most often, tactical grade is used to describe gyro performance with in run bias stability in the 1°/h range and angular random walk (ARW) of 0.15 °/√h or better. Sometimes it can also be used to describe parts with in run bias stability in the range of 0. 5°/h to 5 °/h and in rare cases to include in run bias stability up to 10 °/h.

  • TCAS -

    Traffic Collision Avoidance System is an international standard designed to protect and safely route commercial aircraft based on MODE S data links.

  • TDMA -

    Time Division Multiple Access is a radio channel access method which allows several users to share the same frequency channel by dividing the signal into different time slots. Each "user" or radio on the shared frequency will transmit in rapid succession using its own designated time slot. By using its own time slot, each radio on the shared frequency is able to transmit communications or data without talking over the other radios and experiencing interference.

  • Thermal Imaging -

    Produce images of radiation in the infrared range of the electromagnetic spectrum.

    See also

  • UAV -

    Unmanned Aerial Vehicle. Remotely piloted aircraft commonly referred to as a drone.

    See also

  • USCBP -

    US Customs and Border Control

  • USCG -

    US Coast Guard

  • UTC Time -

    Short for Coordinated Universal Time. UTC is the reference time scale used globally to align time and clocks. Time zones around the world are written using + or – offsets from UTC. UTC has been adopted since 1972 by many countries as reference time scale for their legal time.