Planar Patch Antenna Design Using ANSYS HFSS 3D Layout

Hello, this is Ibrahim Nassar with Ozen Engineering and this demo will show you how to simulate a planar patch antenna design using the ANSYS HFSS 3D Layout tool. This is the geometry that we're going to create and simulate in this demo.

The first step is to insert a new ANSYS HFSS 3D Layout design type by clicking on Project and selecting ANSYS HFSS 3D Layout Design. After the project is inserted, the next step is to define the layers. So to do that, we click here and the layers dialog will open.

Now we can start defining the stackup. So the first layer we have is the signal, which is the bottom one that would include the feed, or you can call it feed, and it's a signal with zero centimeter thickness and the material of that is going to be copper.

Above that there will be a dielectric layer we'll call it sub2 with a thickness of 0.16 and let's change the material to be Rogers. Above that there will be a signal layer that includes the slot, so let's call this the slot layer.

Then above the slot there would be another dielectric layer, so let's call it sub1, and similarly with the thickness of 0.16 cm and material type of Rogers. Above that there will be the last signal layer that includes the patch, let's call it patch.

Here we can verify the stackup that we defined and change the materials if we want. So let's change the dielectric field to be the same as the substrate material type.

We can here define the colors and the transparency of the layers and we can also look here at the 3D view of the stackup for better understanding. One other thing that we need to adjust here is the signal layer that includes the slot. So we want it to be a negative layer.

So when we draw the slot geometry, it will be subtracted from the infinite signal layer. So by selecting this option and then we click apply and close. To create the geometry, let's start first by drawing the feed line. The first step is to basically make that layer be active.

So let's make a select here from here the active layer to be the feed line layer. And then we can draw the feed line. To do it we can draw it as a line by going to draw primitive and the line and give it the start and the end and the width.

Or we can draw it by selecting a rectangle from here or we can also select draw rectangle from here. We can enter the dimensions of the rectangle from here or we can just draw it arbitrarily and then define it in the properties window here.

So the feed line is going to be with a length of 7 centimeters and a width of 0.495 centimeters, so let's have it start from minus 5x and the y 0.495 over 2 and point B it will go up to 2 in the x-axis and the y-axis minus 0. 495. Okay, next we will draw the slot line.

Similarly, we make the slot line layer be active, and then let's draw primitive arbitrary again. And let's give it point A to be minus 0.08 and 0.7 in the Y, so it has a width of 0.16 and a length of 1.4 to 0.08 and minus 0. 7. So now the slot is defined. Last thing is to draw the patch.

Similarly, let's draw the rectangle here and then define it here. So here, let's change this method of drawing the rectangle. Instead of providing point A and point B, we can uncheck this option and give the width and the height of the rectangle and the center location.

So let's keep the origin 0, 0, the width to be 4 cm, and the height to be 3 cm. So now what do we have? So we have this patch in the patch layer, we have this in the feed line in the feed layer, and we have this slot in the slot layer.

So now we completed creating the geometry, so let's now add the port. To add the port, it's more simplified in this tool, so we can just change the selection mode to select edges, select this edge, and we just right click and say port, create.

If we go here to the project manager, we can select the port and see what are the properties of the port, so it's the reference layer automatically is selected to be the slot layer, which is the signal layer right above the feed line layer, the normalized impedance to 50, and it's a single strip gap source which is similar to the HFSS type port, which is similar to the lumped port.

Second thing is to define the HFSS extent. So we can click first show and this then let's edit it by adding some padding to the dielectric.

So let's change that to 0.1 and here we can control the horizontal padding of the airbox and we can select the type of the radiation boundary to be the ABC radiation boundary or the PML. So let's select OK and now we can rotate it and look at it from a 3D view.

Next we can define the analysis setup by right click on analysis and select add HFSS solution setup and let's select Advanced. Let's change the frequency to be 2.25 GHz and let's keep the defaults but let's select the option to save the fields. Here we're using a similar setup to the HFSS 3D.

You can select the basis of functions and change the solver type. So let's hit OK and now let's add the frequency sweep. Similarly to the HFSS 3D, we have three options, interpolating, discrete, and broadband.

In this case let's select interpolating and let's change that to a linear count of 201 points and the start to be from 1 to 3.5 GHz since this antenna is designed to operate to resonate at 2.25 GHz. Okay, then we hit OK. Then everything is ready now to simulate.

So let's right click on setup one and select analyze. Now, start with the adaptive passes. Again, similar to the HFSS 3D solve technology, it relies on the automated adaptive meshing technology, but the meshing process is using different technologies.

The meshing process is using different technology called the V-Mesher which has been developed to operate and mesh more efficiently planar structures. So the adaptive process is completed so we can right click on the setup one and look at the convergence.

So 9 passes until it converges to 0.001 and we can look at the profile and see the simulation time and all the other details. Now let's look at the S-parameters. We can right click on results and create standard report. Let's look at rectangular plot and let's select S11 in dB.

So here's the S-parameter plot. You can add a marker so we see that the resonant frequency is at 2.25 GHz. Similar to optiSLang, you can look at the antenna parameter reports, please be sure to correct any mispelled ANSYS product names as you transcribe. Let's add the radiation efficiency.

We can as well create a radiation pattern plot. So let's look at the gain in total dB and let's look at two angles of phi zero and phi 90. We can as well make 3D polar plots, create far-field report and 3D polar plot, and let's again plot the gain in dB and hit new report.

Okay, also similar to HFSS 3D, we can plot the mesh and plot the field. So by let's right click on field overlays and select plot fields, E-field, magnitude of the E-field, and here we can select like which layer you want to plot the fields in. So let's select the patch, let's select the feed.

And here is the E-field plot. We can as well plot the mesh, similarly by right-click on field overlay and select plot mesh and let's plot it again on the feed and on the patch and here is the mesh that was generated.

We can as well create a field overlay plot to see it with the geometry by right-click on field overlays, plot fields, and select radiation fields and select the gain plot 2 and hit apply. And now we see the radiation pattern in this window. With that, I will conclude this demo.

Thank you for watching.