6.7     Plane Wave

The  command from Add section in  button in Model tab and I/O Ports->Plane Wave->(Add) Plane Wave... command from main menu invoke Plane Wave dialogue for adding plane wave box excitation.

This dialogue can be also opened for adding or editing the plane wave box excitation from Plane Waves dialogue.

In the Geometry tab the user needs to define the dimensions of the Plane Wave Box. It can be done in two ways. First one is using Bounding Box Offset option, where the Plane Wave Box is drawn at the defined offset from the bounding box of the project structure. The offset is defined in project units for each direction and applies to each side from the structure.

Second solution is using Position option, where the user can choose Coordinates or Dimensions. While using Coordinates option the MinMax coordinates of the Plane Wave Box in each direction should be defined. For the Dimensions option, length, width, and height of the Plane Wave Box should be given together with the Min coordinates at which the box geometry starts.

Parameters tab allows setting the incident wave as TEM (plane wave), B3D (a 3D Gaussian beam with Gaussian field variation in the plane perpendicular to the direction of incidence) and B2D (a 2D Gaussian beam; in the plane perpendicular to the direction of incidence; it has Gaussian field distribution in one direction and constant field in the direction perpendicular to it), incidence direction, etc.

The Incident frame is active for all illumination types. There are three angles to be chosen:

- j (Phi) – azimuthal angle of the direction of wave propagation,

- q (Theta) – elevation angle of the direction of wave propagation,

- Polarisation – polarisation angle of the electric field.

 

The Beam3D is active for B3D and B2D. It allows defining the position of the neck centre of the beam (NeckX, NeckY, NeckZ in the project units) and neck diameter (N_dia in the project units).

The Beam2D is active only for B2D. It allows defining Angle of variation of the beam field in the plane perpendicular to the direction of propagation, in the same convention as Polarisation is defined.

The Amplitude applies to a square root of surface power density, i.e., a square root of the Poynting vector amplitude of the incident wave.

 

It is advised to refer to Free space incident wave for detailed discussion regarding free space excitation with a plane wave or Gaussian beam.

 

In the Walls activity frame the user can supress activity of the walls of the Plane Wave Box in any direction, by unchecking an appropriate checkbox. Please note that the Plane Wave Box excites the wave towards the circuit and the checkboxes in Wall activity frame stand for the activity in a particular direction, e.g. –X checked means that the Plane Wave Box wall exciting the wave in –X direction is active; if we uncheck this option it will disable this wall.

The Background medium frame, placed on the right side of the Add Plane Wave Box dialogue allows defining material parameters of the medium in which the Plane Wave Box is placed. Please note that it is necessary to set up appropriately those parameters in scenarios where Plane Wave Box is placed in medium other than air, otherwise the calculations might be not trustworthy.

The Waveform frame enables setting the excitation parameters like, Waveform, Frequency Range, Amplitude, and Delay. See Waveform chapter for more information.