Remcom announces a major update to XGtd®, a tool for analyzing far zone radiation, RCS, and EMI/EMC for electrically large platforms. The new version, Release 2.6, includes new functionality for radar cross section (RCS) applications including a more accurate hybrid model based on Physical Optics (PO) and the Method of Equivalent Currents (MEC), new output types for far zone RCS and antenna gain field points, ray path visualization to far zone field points, and visualization of edges considered by the calculation to be part of curved surfaces.

Greg Skidmore, director of Remcom’s propagation division, said, “We have a strong customer base in military-related markets, and their need for radar applications is growing. In designing the new version of XGtd, we focused on improving its RCS functionality for these types of applications. With our new RCS model, which combines both PO and MEC in its calculations, customers should notice significant improvements in accuracy with options for highly efficient simulations."

New MEC/PO Hybrid Model for RCS Calculations:

The new hybrid model is based on the Method of Equivalent Currents (MEC) and Physical Optics (PO), resulting in improved accuracy in all scattering directions that can be applied to RCS calculations for perfect electric conductors or dielectric surfaces.

New Far Zone Output Types for RCS and Antenna Radiation:

New far zone outputs include scattering amplitude and excess time of arrival for ray paths. Additionally, electric field magnitude and phase, complex impulse response, and Poynting vector magnitude, which were previously restricted to near zone locations, can now be calculated at a user-specified distance from the transmitter.

Ray Path Visualization to Far Zone Locations:

Ray paths for far zone antenna gain and RCS calculations can now be displayed in the graphical user interface. Rays will be colored according to strength, allowing users to identify strong scattering features on the project geometry.

Curved Surface Visualization in the User Interface:

Adjacent geometry faces within a specified angle range will be treated as a smooth curved surface during calculations. For far-zone RCS calculations, this impacts which models will be used (physical optics or MEC), and for antenna radiation it designates surfaces where UTD creeping wave calculations may be applied. Visualization of the edges and smooth surfaces will give users a better understanding of how their geometry will be used in the calculations.

XGtd is a general purpose ray-based electromagnetic analysis tool for assessing the effects of a vehicle or vessel on antenna radiation, estimating radar cross section (RCS), and predicting coupling between antennas. Based on techniques such as Geometric Optics (GO), the Uniform Theory of Diffraction (UTD), Physical Optics (PO), and the Method of Equivalent Currents (MEC), performance and memory requirements are less dependent on the electrical size of objects than full wave methods. This makes it ideally suited to applications with higher frequencies or very large platforms where requirements of a full physics method, such as Finite Difference Time Domain (FDTD), may exceed available computational resources.

For more information on XGtd, the detailed feature list, and a visual tour, visit Remcom’s website at

XGtd users without an active Remcom Professional Support contract can upgrade to Release 2.6 by contacting

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