XGtd® is a ray-based electromagnetic analysis tool for assessing the effects of a vehicle or vessel on antenna radiation, predicting coupling between antennas, and predicting radar cross section (RCS).  It is ideally suited for applications with higher frequencies or very large platforms where the requirements of a full physics method may exceed available computational resources.

XGtd’s capabilities extend well beyond standard ray tracing codes, incorporating techniques including Geometric Optics (GO), the Uniform Theory of Diffraction (UTD), Physical Optics (PO), and the Method of Equivalent Currents (MEC). XGtd provides high-fidelity outputs tailored to its intended applications.

Computational methods include:

  • Ray tracing methods: Shooting and bouncing ray and image theory
  • E-field evaluations using UTD, GO, PO, and MEC
  • High-fidelity field predictions in shadow zones including creeping wave effects
  • Multipath calculations including reflections, transmissions, wedge diffractions, surface diffractions, and creeping waves


XGtd Features

X3D RCS Model is a GPU-accelerated, multi-threaded 3D propagation model providing highly optimized calculations for far zone radar cross section (RCS) analysis, using methods based on Physical Optics (PO), the Method of Equivalent Currents (MEC), and the Uniform Theory of Diffraction (UTD).  X3D’s exact path and targeted ray shooting algorithms provide higher accuracy than traditional ray tracing models that are based on the shooting-and-bouncing ray (SBR) method.  The model can support frequencies up to millimeter waves.

Full 3D Model The Full 3D propagation model predicts the paths by which energy travels from the transmitting antenna to the receiving location. This model supports interactions with structures in the near zone for applications such as
co-site interference analysis, anechoic chamber analysis, or far zone antenna radiation from a platform-mounted antenna.  It also provides an alternative method for predicting far zone RCS.

Graphical User Interface XGtd's modular 64-bit GUI makes it easy to import objects to set up projects for various electrical large platforms. Users can simulate co-site analysis, antenna placement, radar cross section, and anechoic chambers.

Feature Import Support for KMZ, COLLADA, STL and DXF formats for object import.

Large Platform Simulations XGtd’s methods are less impacted by the platform’s electrical size than full wave techniques, supporting larger structures and higher frequencies.

Ray Path Visualization Display ray paths for far zone antenna gain, RCS calculations, or antenna coupling. Rays are colored according to strength, allowing users to identify scattering features.

XFdtd Compatibility for Higher Fidelity Antenna Patterns Calculate antenna radiation patterns for complex antenna designs using XFdtd. Import into XGtd to determine effects of placement on electrically-large platforms.

Antennas Import simulated antennas from XFdtd or create textbook antennas for use as transmitters and receivers.

Materials Electrical properties of the scene can be defined down to the facet level. An installed database of materials includes metal and absorbers.

Outputs Users have quick access to outputs such as direction-of-arrival, complex impulse response, E-field vs. time, and E-field vs. frequency for each transmitter-receiver link. These ASCII-based files can be plotted in the tool or easily post-processed externally. S-parameters are exported to touchstone.



Learning and Documentation

Application Examples




XGtd Brochure

XGtd Brochure