Feko 2017.2 Release Notes

The Feko 2017.2 update includes the features, enhancements and bug fixes documented below.

Prominent features

  • Custom user specification of the convergence criteria for the finite difference time domain (FDTD) solver.
  • Improved support for PEC regions embedded in dielectric regions for the finite element method (FEM).


Figure 1. Partial view of a coaxial diplexer model (left) and mesh (right) with the perfect electric conductor pins meshed into tetrahedra with the dielectrics and solved as part of the FEM solution.
Note: Feko 2017.2 is a cumulative update that contains changes from all previous releases. It can be applied as an update to an existing installation of Feko 2017 or it can be installed without first installing Feko 2017.

CADFEKO

Features

  • Support for setting FEM regions to the Perfect electric conductor medium. FEM PEC regions are meshed into tetrahedra, but do not add to the number of unknowns in the FEM solution. (2017.2)
  • The advanced solution frequency settings are extended with options to specify the minimum time interval, the maximum time interval and the convergence threshold for FDTD simulations. (2017.2)
  • The near field optimisation goal is extended to support optimisation of (normalised) electric and magnetic flux density. (2017.2)
  • The far field optimisation goal is extended to support the optimisation of realised gain. (2017.2)
  • The API is extended to provide rational interpolation functionality to the scripting environment.
  • The meshing library is upgraded to the latest version. (2017.2)

Resolved Issues

  • A problem with the file browser file extension filter for mesh imports is resolved. The filters for CADFEKO mesh (.cfm) and (.fek) files did not show files of these types in the file browser when opening files to import. (2017.2)
  • An issue is resolved with configuration specific cable sources that could trigger "ERROR 38353: Multiple cable sources defined at the same connector pin combination are not allowed" during the simulation. (2017.2)
  • An issue is resolved that prevented changes from being made to the medium properties of a face. The problem was encountered when creating a cone or flare primitive with the top dimension set to zero and then modifying this dimension to be non-zero. The face created during this modification would have "Perfect electric conductor" medium properties and changes to the face medium would not be applied. (2017.2)

EDITFEKO

Features

  • The ME card (dielectric region) is extended to allow defining perfect electric conductor FEM tetrahedra. (2017.2)
  • The FD card (FDTD settings) is extended with the options to specify the minimum time interval, the maximum time interval and the convergence threshold for FDTD simulations. (2017.2)

POSTFEKO

Features

  • Support the display of electric and magnetic flux densities for near field graphs and views. (2017.2)
  • The file size is reduced for POSTFEKO .pfs files sessions that contain imported data. (2017.2)
  • The API is extended to provide rational interpolation functionality to the scripting environment.
  • The .fek file version is increased to 158 to accommodate new features. (2017.2)

Resolved Issues

  • The visualisation of stored data for near field requests using local workplanes is corrected. (2017.2)
  • An issue with cable probes used across multiple configurations is resolved. If cable paths were swapped between configurations, probe results could be incorrectly labelled, associated with the wrong configuration or not be available for plotting. (2017.2)

Solver

Features

  • Improved handling of PEC regions embedded in FEM solution domains. (2017.2)
  • Custom user specification of the FDTD convergence criteria is supported. (2017.2)
  • Support is added to the FDTD solver for left/right handed polarisation and ellipticity of a plane wave source. (2017.2)
  • Irradiation MTL cable analysis for frequency domain FDTD is supported. (2017.2)
  • The stabilised MLFMM now supports specifying the residuum for the stopping criteria. (2017.2)
  • The MUMPS sparse LU preconditioner is used for extremely large MLFMM problems (more than 2^31-1 matrix entries) instead of the fall-back SPAI preconditioner. (2017.2)
  • Various computational libraries are upgraded to improve support for large models run with the FEM and MLFMM. (2017.2)

Resolved Issues

  • An issue causing incorrect reflection coefficient phase values for the planar Green's function when the phase reference is not set to z=0 is resolved. (2017.2)
  • A bug is fixed that caused incorrect results (small differences) for physical optics problems connected to a ground plane. (2017.2)
  • An issue is resolved that caused an internal error state when solving certain MLFMM models containing dielectric media in parallel. (2017.2)
  • Incorrect transmission coefficients reported for a negative incident theta angle are resolved. (2017.2)
  • An internal error condition that occurred when setting all ports active for S-parameter requests with four or more ports is fixed. (2017.2)
  • Memory usage of the out-of-core pre-conditioner used for large MLFMM problems is improved. (2017.2)
  • Parallel memory reporting is improved at various stages for distributed MPI parallel examples. (2017.2)
  • A memory location fault encountered for certain MLFMM problems that use the MUMPS preconditioner is prevented. (2017.2)
  • Rays were missing from .ray and .bof files when using distributed parallel MPI Feko runs. (2017.2)
  • An issue is resolved that caused parallel Feko runs to terminate because a host list file could not be written. (2017.2)
  • An error regarding the size of the mesh in relation to the number of processes used was issued incorrectly for certain small FDTD examples. (2017.2)

Support Components

Feature

  • A shared Lua module gives the user access to common actions. The module provides the ability to read values from an ASCII file. (2017.2)