Hello,

Far Fields Report: Radiation Pattern

To plot the radiation pattern, you need to first define a geometry over which to plot. In this example, we will plot over the xz (phi = 0deg) and yz (phi = 90deg) cutplanes. I am using the patch antenna from Lab 9 for this demonstration since transmission lines are not designed to radiate. Right-click on 'Radiation' in the Project Manager window and select 'Insert Far Field Setup -> Infinite Sphere...'.

In the window that appears, it is helpful to change the name of the geometry to something that you will remember later. In this example we are plotting over the xz and yz cutplanes, so I will name this 'XZ/YZ'. Now we must think about how to define the xz and yz planes in terms of phi and theta. The xz plane is equivalent to phi = 0deg and theta = [-180,180)deg. The yz plane is equivalent to phi = 90deg and theta = [-180,180)deg. Mathematically, theta is bound between 0 and 180deg, but the software allows theta to go from -180deg to 180deg or even 0deg to 360deg if you prefer. So, we can set phi to start at 0deg and stop at 90deg with a step size of 90deg. This gives us phi = 0deg,90deg. And we can set theta to start at -180deg and stop at 180deg with a step size of 1deg. This gives us theta = -180deg,-179deg,...,179deg,180deg.

Now, right-click on 'Results' in the Project Manager window and select 'Create Far Fields Report -> Radiation Pattern'. In the window that appears, make sure the geometry is set to 'XZ/YZ'. Set the Primary Sweep to 'Theta' since we want the polar graph to sweep over theta and show seperate traces for different values of phi. We will plot the phi-polarized gain and the theta-polarized gain on one graph. Select 'Gain' under Category, then hold Ctrl and select 'GainPhi' and 'GainTheta' under Quantity, then select 'dB' under Function. Click 'New Report' to create the plot.

You can change the scaling by double-clicking on the numbers on the radial axis. Make sure you are on the 'Grid' tab and scroll down until you see Min Scale, Max Scale, and Spacing. Typically, we look at radiation patterns over a 40 dB range, that is the difference between the Max and Min. So change the 'Min Scale' to '-30', the 'Max Scale' to '10', and 'Spacing' to '10'. Click OK to close this window.

You should see 4 different traces corresponding to GainPhi Phi=0deg, GainPhi Phi=90deg, GainTheta Phi=0deg, and GainTheta Phi=90deg. The Phi=0deg traces are for the xz plane and the Phi=90deg are for the yz plane, and theta is the variable that is swept on the polar plot with 0deg being the positive z direction.

Thanks,

Dear Radouane,

Export the data u have plotted as .csv file. Simply right click on ur plot and export as .csv file. This .csv file you can open in any specialised figure/diagram plotting tool such as Origin or simply MS Excel also. Now you have your radiation data along with the angles, you can plot it as u like. By using special software like origin the figure you get are of much better resolution and suitable for publication(reputed journals usually ask for it). Also it gives u freedom to plot your figures in your own desired form, compare various data, select symbol for different plots, line color width etc. In totality it gives u a better version of your plot.

go for hfss - results

- create far field results -> radiation pattern

- under trace option -> look for primary sweep - theta (u change the values of theta here, if needed)

- under "families" tab look for phi (u can define the angles for phi here)