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Exterior Field

The Exterior Field Probe utility is used to obtain electric or magnetic field data at a point outside of the computational domain. These point locations may be at great distances from the confines of the problem space. The locations of exterior fields are specified by identifying the coordinates of the far field locations in the user interface. While most useful for probing fields outside of the domain, this probe does allow for probe locations within the domain.

The exterior field algorithm computes the total field, including the near field, the inductive field, and the far field. The Exterior Field Probe algorithm operates by computing electric and magnetic surface current densities on a far field integration surface that is just inside the domain boundary. These current densities are synthesized, with the proper retardation times, to provide the electric or magnetic fields at close or at distance points from the integration surface.

Instructions

  1. Click FieldField Probe Image 16 within the Probes section under the EMA3D tab in the ribbon. Then click Exterior Field in the drop-down list.

    2. exterior probe 1

  2. The default probe field type is Electric. To measure the magnetic field, change the probe field type to Magnetic in the Properties panel. The time, location, and orientation properties can also be adjusted.

    3. exterior probe 2

  3. Adjust the orientation and location in the Properties Panel to set the probe’s position and direction.

    4. exterior probe 3

  4. The probe will appear in the model window as a large green dot and will be added to the Simulation Tree under the Probes node.

    5. exterior probe 4

  5. The probe can be renamed or deleted at any time by right clicking it in the Simulation Tree. It can also be edited by double clicking its name.

    6. exterior probe 5

  6. To visualize the Exterior Field Probe results, see here.

General
Options

Entry

Meaning

Name

Name of the probe.

Field Type

Field quantity to measure.

Time
Time Options

Entry

Meaning

Start: Match Domain

Match the start time to the FDTD domain. Blue indicates True.

Start: Value

The probe start time.

Step: Match Domain

To which domain to match the probe time step:

  • Highest Frequency sets the probe time step such that it captures up to the highest supported frequency of the domain (this time step is coarser than the Domain time step and results in smaller files)

  • Time Step matches the probe time step to the FDTD domain time step.

  • False allows the user to set the probe time step manually.

Step: Value

The probe time step [s].

End: Match Domain

Match the end time to the FDTD domain. Blue indicates True.

End: Value

The probe end time [s].

Position
Position Options

Entry

Meaning

X

X location of the probe.

Y

Y location of the probe.

Z

Z location of the probe.

Orientation
Orientation Options

Entry

Meaning

Theta

The theta coordinate of the probe.

Phi

The phi coordinate of the probe.

r (m)

The distance from the domain center [m].

See Also

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