The Global Positioning System (GPS) Interference and Navigation Tool (GIANT) is a physics-based, constructive and repeatable simulation model that computes Position, Navigation and Timing system performance and its impacts on mission effectiveness (e.g. CEP, Pk) in a benign or electronic contested environment. GIANT includes databases of satellites, receivers, antennas, inertial navigation systems (INS), and emitters, as well as a comprehensive User Manual.
GIANT is accredited for use in the GPS Warfighter Collaboration Cell (GWCC) and is included in the Air Force Standard Analysis Toolkit and Army Space Operations System (SOS). GIANT supports the Distributed Mission Operations Center-Space (DMOC-S), GPS Virtual Flight Test Facility, multiple studies, analyses, and AoAs, ionospheric scintillation, flex power, and GPS jamming range events, and is integrated into a number of other systems.
With hundreds of users of GIANT worldwide, GIANT is the premier GPS performance model and provides a simulation and modeling environment for analysts, engineers, testers, operators, and decision makers.
The GIANT software suite includes a user-friendly graphical interface, data visualization and post-processing tools. The GIANT simulation is a discrete time-stepped simulation that runs much faster than real-time. A typical GIANT simulation run consists of one or more GPS/INS-equipped platforms moving along a route, employing optional air-to-ground or surface-to-surface precision guided munitions against multiple targets, in an electronic environment that includes zero to many GPS interference sources or jammers, and a GPS constellation; area analyses are also supported.
The Configuration Control Board (CCB), chaired by SSC/CGG, manages the software baseline. Formal training is periodically provided and is also available on request. Information on upcoming training dates is provided on the GIANT website.
The simulation has been extensively verified and validated, including the geospatial model, coordinate systems, orbit propagation algorithms, Jammer-to-Signal ratios, and GPS accuracy metrics. For example, the J/S ratios produced by GIANT were validated against flight test data consisting of single and multiple jammer scenarios across independent GPS flight tests.
The simulation evaluates electromagnetic signal propagation and visibility using detailed ellipsoid, geoid, and digital terrain models. The resulting geometries and power levels determine the signal environment experienced by the modeled antenna and receiver systems. Antenna, including antenna electronics, and receiver behavior are modeled, ultimately resulting in the calculation of position error as a function of the combined GPS/INS solution at each point along the route. Routes can be combined to produce aggregate or engagement/battle-level performance and effectiveness metrics across multiple routes. Multiple time-based, event-driven performance output files are available and provide a variety of low and high level information.