This blog illustrates how the EMA3D and MHARNESS simulation tools can be used to simulate the electric filed produced by an antenna inside a cavity. Below is a brief overview of the steps needed to complete the simulation and a full demonstration is provided in the video link.
The first step in preparing the simulation is to define the simulation domain. The domain should encloses all the geometries that need to be analyzed. In this demo we will use the following settings:
Lowest Frequency: 10 MHz
Highest Frequency: 500 MHz
Under Lattice in the Properties Panel adjust the Minimum values to be:
X: −420 mm
Y: −420 mm
Z: −1920 mm
Under Lattice in the Properties Panel adjust the Minimum values to be:
X: 1920 mm
Y: 1920 mm
Z: 420 mm
In this step all the material properties should be assigned in order to simulate the problem. Aluminum material properties will be assigned to all the enclosure box surfaces with electric conductivity of 1.2e7.
In order to capture the electric field produced by the antenna, an electric field probe should be defined at the area of interest. For this demo, we are going to specify the coordinates of the probe by entering values in the Bound Tab.
Under Minimum in the Properties Panel adjust the values to be:
X: 540mm
Y: 1080 mm
Z: −359.99 mm
Under Maximum in the Properties Panel adjust the values to be:
X: 840 mm
Y: 1380 mm
Z:-60 mm
In this step the MHARNESS cable will be defined for the antenna to model the induced voltage and currents and a pin voltage source will be assigned at the end of the antenna wire to excite the antenna conductor.
After the pin voltage source is defined, we need to determine the excitation voltage signal for the simulation. In this demo, a Derivative Gaussian signal will be used.
Before starting the analysis, we need to mesh the model geometry. In this step, the mesh will be created for all the geometries inside the simulation domain defined and the simulation will be run.
After the simulation is completed, we can post process the results. In this type of problems, we have 2 options to select; 1) Compute filed statistics which calculates the field averages as well as the shielding effectiveness, and 2) Compute field averages. In this demo we will select Compute Field Averages as shielding effectiveness is not a useful measure in this demo.
A complete demonstration of this work flow is shown in the video link below: