Avionics are the onboard electronic systems used on aircraft, satellites, and spacecraft to perform functions including communications, navigation, flight control, power management, and data handling. In modern vehicles, avionics systems are highly integrated and generate continuous data streams across multiple buses throughout every phase of operation.
A Channel is an individual telemetry signal recorded from an Asset, typically represented as a time-series measurement like temperature, voltage, or pressure.
Data decimation is the process of reducing telemetry resolution by dropping samples from a data stream to reduce storage requirements or transmission bandwidth.
A data historian is a software system specifically designed to collect, store, and retrieve time-series data from industrial equipment, sensors, and control systems. Historians were originally developed for process manufacturing industries and remain the dominant data infrastructure in energy, manufacturing, and utilities.
Decommutation is the process of extracting individual sensor measurements from a framed telemetry data stream by reversing the time-division multiplexing applied during commutation. Frame synchronization must be established before decommutation can begin.
Delta-v is a scalar measure of the velocity change required to perform a spacecraft maneuver such as a launch, orbital insertion, course correction, or landing. It is the primary metric used in mission planning to determine propellant requirements, with the total mission delta-v budget setting the constraint on how much propellant a vehicle must carry.
Guidance, Navigation and Control (GNC) is the integrated discipline that combines sensor measurements of a vehicle's position and orientation, algorithms to determine desired trajectory corrections, and actuator commands to execute those corrections. GNC systems are present on all aerospace vehicles from launch vehicles to satellites to autonomous aircraft.
Ground support equipment (GSE) refers to the hardware, software, and facility systems used to support, fuel, test, and operate a vehicle or spacecraft during ground operations before and after flight.
Hardware-in-the-loop (HIL) testing is a technique for validating embedded control systems by connecting real controller hardware to a real-time simulation of the physical system it will operate. The simulation replicates sensors and actuators so the controller responds as it would in operation.
A Flow is a processing step within a Sift ingestion configuration that determines how incoming telemetry is handled and mapped as it enters the system.
Ingestion latency is the time between a sensor generating a measurement and that data becoming queryable in an analysis system typically measured in milliseconds for real-time telemetry pipelines.
IRIG 106 Chapter 10 is a digital data acquisition and recording standard maintained by the Range Commanders Council that defines interfaces and operational requirements for solid-state on-board recorders. It specifies how multiple data types, including PCM, MIL-STD-1553, analog, video, and discrete signals, are captured and time-stamped in a single recording.
MIL-STD-1553 is a serial data bus standard published by the US Department of Defense that defines the mechanical, electrical, and functional characteristics of a command/response multiplexed data bus. Originally designed for military aircraft avionics, it is now widely used in spacecraft on-board data handling systems as well.
The noise floor is the threshold of background interference in a measurement system below which real signals cannot be distinguished from sensor or electrical noise.
The Nyquist frequency is half the sampling rate of a data acquisition system. It represents the upper limit of frequencies that can be accurately captured without aliasing. To correctly sample a signal of a given frequency without distortion the sampling rate must exceed twice that frequency.
OPC UA (Open Platform Communications Unified Architecture) is a cross-platform, vendor-neutral communication standard that defines how industrial devices, controllers, and software systems exchange data. Defined by the IEC 62541 specification and maintained by the OPC Foundation, it supports both client-server and publish-subscribe communication patterns and includes built-in security through encryption and certificate-based authentication.
Root cause analysis (RCA) in hardware engineering is the process of tracing an observed failure or off-nominal event back to its originating cause using telemetry logs and sensor data.
SCADA (Supervisory Control and Data Acquisition) is a system architecture that uses hardware and software to collect real-time data from sensors and equipment across industrial operations, enabling operators to supervise and control physical processes from a central interface.
Specific impulse (Isp) is a measure of rocket or jet engine efficiency expressed as the amount of thrust produced per unit of propellant mass flow rate per second. It is the primary metric used to compare propulsion system performance with higher values indicating more efficient use of propellant. It is measured in seconds.
Stream processing is a data handling technique where data is processed continuously as it is produced, rather than stored first and processed later. In hardware telemetry applications, stream processing enables rules, anomaly detection, and data shaping to run on incoming sensor data in real time as it flows from a vehicle or test rig into a storage and analysis system.
Structural fatigue is the progressive degradation of a material caused by repeated cyclic stress loading. Fatigue damage accumulates even when peak stress levels remain well below the material's rated tensile strength making it a primary concern in aerospace structures subject to vibration thermal cycling and repeated pressurization and depressurization events.
Telemetry is the automated process of collecting and transmitting sensor data from remote or inaccessible systems to a ground station or data processing environment for analysis.
