December 11, 2018: The content below helps navigate the new features in this release. A full list of updates is available in the Reference Manual's Appendix.

Distributed Circuit Component

The circuit component editor includes a distributed option that increases accuracy when a component is attached to a transmission line. When selected, the excitation is spread across the width of the transmission line connected to the component.

XF assumes an analytic field distribution under the transmission line where the voltage and current density are evenly distributed across the component's width. XF accounts for components that are placed across inhomogeneous materials.

Surface Current Sensor

The surface current sensor computes the electrical current on a metal surface, and is primarily used for building antennas that perform well at multiple frequencies. Users can view the surface current on only the antenna rather than the entire complex circuit in order to more easily identify issues and make the appropriate changes.

The sensor can collect data on any part that is a good electrical conductor, and it supports both XACT and staircased parts.

Array Analysis

XFdtd Release 7.8.0 includes an array analysis macro that optimizes input phases for either arrays or subarrays in order to obtain the maximum possible realized gain in all directions. It then plots the cumulative distribution function of EIRP for the array configurations.

XFdtd Release 7.9.0 replaces the macro with array optimization.

Apply Matching Circuit Script

The apply matching circuit macro inserts a matching circuit into an unmatched feed as a post-processing step and updates the results to reflect a matched antenna.

Users designing an antenna's matching circuit can pass S-parameters and efficiency results to a circuit solver, such as Optenni Lab or ADS, where a matching circuit is synthesized. After the matching circuit is exported to an *.s2p file and then imported into XF, this script places the matching circuit between the voltage source and antenna and recomputes results.

Standalone Radiation Efficiency

XF's system sensor reports the standalone radiation efficiency in cases where there are inactive waveguides or circuit components. This is similar to radiation efficiency, but it does not include the losses from inactive components or waveguides. This is primarily used to directly feed the system's antenna ports and export the efficiencies and S-parameters to an external tool, making it particularly useful to ADS users who export XF's S-parameter matrix.

Cloud Computing with Rescale

This release introduces the multithreaded daemon script, which configures and submits XF simulations for remote execution via the Rescale high performance cloud computing platform. It also downloads simulation results and places them back in the appropriate location on the local filesystem upon completion, allowing XF users to submit simulations to Rescale and view the results without manually setting up both the jobs and compute clusters, or monitoring simulations for completion and then retrieving their output.


XF's slice modeling operation cuts one part into two parts. It is similar to a boolean chop, except that it utilizes a single cutting plane. This operation can be used to separate an undesired portion of a part for deletion, such as the feeding structure of an antenna needing to be redesigned.

Users can also slice multiple parts simultaneously.

Photoconductive Semiconductor Switch

The photoconductive semiconductor switch (PCSS) circuit component definition simulates a semiconductor device that conducts electricity when illuminated. PCSS components should be used when only time-domain results are of interest.

Object Encryption

Users can password protect both material and circuit component definitions in order to secure an object's associated information. The encrypted information can be viewed and edited by reentering the password.

This protective measure ensures that the intellectual property associated with the object is accessible only to authorized users, while still allowing the object to be shared in projects and included in simulations.

Surface Roughness

The surface roughness of a copper trace affects its conductivity by creating resistance and causing power loss as the current moves along the trace toward the antenna. Higher frequencies increase the current's deviation from an ideal, perfectly smooth surface and result in decreased efficiency.

Users can control this deviation by adjusting the surface roughness in the material editor, allowing them to assess the conductivity loss captured in the output and its effect on efficiency.

Optenni Lab Integration

Support for Optenni Lab 4.2 has been added, so users can export to Optenni Lab through the right-click menu of XF's results browser when a 3-D far zone radiation pattern is selected. Based on the far zone selection, XF determines the full S-parameter matrix, efficiencies, available powers, and other data to send to Optenni Lab.

Graph Updates

This release includes three main updates to XF's graphing capabilities:

Additional Capabilities

There are over 40 usability, performance, scripting, and other updates in this version.

Here is a select list of modifications: