Wave Optics Module Updates

For users of the Wave Optics Module, COMSOL Multiphysics® version 5.3 brings new variables for postprocessing far-field radiation patterns, new default settings to improve your modeling experience, and a new Fresnel Lens tutorial model. Review all of the Wave Optics Module updates in more detail below.

New Far-Field Postprocessing Variables

Additional postprocessing variables have been added to the physics interfaces that calculate far-field radiation patterns. The previous gain variable is clarified with gain and realized gain by the input impedance mismatching factor. These postprocessing variables can be used in far-field plots to visualize the characteristics of an antenna.

  • EIRP and EIRPdB: effective isotropic radiated power and its dB-scaled value
  • gainEfar and gaindBEfar: gain excluding input mismatch and its dB-scaled value
  • rGainEfar and rGaindBEfar: realized gain including input mismatch and its dB-scaled value
A plot illustrating the new far-field postprocessing variables in COMSOL Multiphysics version 5.3.

The far-field radiation gain and realized gain pattern on an xy-plane of a new Application Library example, a double-ridged horn antenna at 3 GHz.

The far-field radiation gain and realized gain pattern on an xy-plane of a new Application Library example, a double-ridged horn antenna at 3 GHz.

Application Library path for the new far-field postprocessing variable: RF_Module/Antennas/double_ridged_horn_antenna

Surface Magnetic Current Density

The new Surface Magnetic Current Density boundary condition has been added to the Electromagnetic Waves, Frequency Domain interface and specifies a surface magnetic current density at both exterior and interior boundaries. Magnetic current density is described by a 3D vector. However, because it flows along a surface, it can be alternatively represented for more efficient modeling. To achieve this, the COMSOL Multiphysics® software projects this current density onto a boundary surface and neglects its normal component. The new boundary condition has been provided for special modeling situations, such as for modeling electric dipoles.

An example of a model using the Surface Magnetic Current Density boundary condition.

Surface magnetic current density (blue arrows) on a cylindrical coil through use of the Surface Magnetic Current Density boundary condition in the Electromagnetic Waves, Frequency Domain interface. The electric field pattern (cone) resembles that of a short dipole antenna.

Surface magnetic current density (blue arrows) on a cylindrical coil through use of the Surface Magnetic Current Density boundary condition in the Electromagnetic Waves, Frequency Domain interface. The electric field pattern (cone) resembles that of a short dipole antenna.

New Default Settings for Enhanced Usability

Many default settings have been updated to reduce the number of modeling steps and enhance usability:

  • Mesh reads the frequency or wavelength from study steps automatically for the Electromagnetic Wave, Frequency Domain interface
  • Finer angular resolution (theta 45, phi 45) for the 3D far-field plot
  • Automatic excitation is now turned on for the first port
  • Eigenfrequency search method around shift is now set to Larger real part for Frequency-Domain Modal analyses
  • The Linper operator is applied internally for excited ports and no longer needs to be specified by the user for Frequency-Domain Modal analyses
  • The S-parameter descriptions have been simplified