Changes

Before you begin to set up the geometry of your project, let’s quickly ensure that the project units are set up correctly. First, open up the Units Dialog box by selecting the Units button of the Simulate Toolbar (or using the keyboard shortcut Ctrl+U). Make sure the length units are Millimeters, and select OK to continue. Similarly, for frequency and bandwidth, select the Frequency button of the Simulate Toolbar (or use the keyboard shortcut Ctrl+F) to open the Frequency Dialog box. Make sure both the frequency and bandwidth are 1GHz, and select OK to continue.

==1.2 FDTD Module Navigation==

With the line tool selected, click the origin (0,0,0), and drag the mouse to start drawing a line. While still in “Draw Mode”, press and hold the Alt button of the keyboard. This forces the drawn line to be constrained along the alternate Z-axis (normal to the default XY plane on which the mouse pointer moves). Observe the changing Length value in the dialog box as you drag the mouse back and forth. When the length reaches a value of 150 units, left-click to “lock-in” the value. You may also left-click at any point and adjust the length by typing in a value of 150 in the object’s property dialog.

Since the center frequency of the project is 1GHz, the operating wavelength is:

The boundary Conditions at the six faces of the computational domain can be set by selecting the menu item Simulate  Computational Domain  Boundary Conditions… or by right clicking on the “Boundary Conditions” item in the “Computational Domain” section of the Navigation Tree. By default, EM.Cube’s [[FDTD Module]] assumes an open-boundary physical structure. All the six boundaries default to PML, or Perfectly Matched Layer, which you are going to maintain for this tutorial lesson. But the dropdown lists allow you to also choose PEC, or a Perfect Electric Conducting boundary, or PMC, a Perfect Magnetic Conducting boundary.

==1.5 Source Definition==

EM.Cube’s [[FDTD Module]] generates a Yee mesh of your physical structure. The mesh properties can be accessed by clicking the Mesh Settings button of the Simulate Toolbar (or using the keyboard shortcut Ctrl+G or via the menu Simulate  Discretization  Mesh Settings). For this tutorial, accept the default value of 20 Cells/eff for Minimum Mesh Density.

To view the mesh, click the Show/Generate Mesh button of the Simulate Toolbar (or alternatively use the keyboard shortcut Ctrl+M). For this particular project, the mesh view does not reveal much because the mesh of a vertical line object conforms to the grid. In general, the mesh view shows how the simulation engine sees your physical structure. You can also display the three mesh grid planes by right clicking on one of the three items XY Grid Plane, YZ Grid Plane, or ZX Grid Plane in the “Discretization” section of the Navigation Tree and selecting Show from the contextual menu. To remove the grid planes from the project workspace, open the same contextual menu and select Hide.

==1.7 Defining Project Observables==