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Microstrip Patch Antenna Radiation Pattern

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I examine the "Microstrip Patch Antenna" example in the application libraries. I just want to see the radiation pattern of the antenna. I selected "emw.gaindBEfar" expression to see the far-field gain pattern in dB. Eventually, I can see it now. But the grid values around the pattern are not fit with the real gain values as you can see in the following figure. What are these grid values and how can I switch them to the proper values?



2 Replies Last Post Feb 20, 2019, 8:07 a.m. EST
Robert Koslover Certified Consultant

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Posted: 5 years ago Feb 19, 2019, 10:18 a.m. EST
Updated: 5 years ago Feb 19, 2019, 10:20 a.m. EST

Those grid values are associated with the geometry of the antenna and the orientation of the pattern, but not the far-field values (e.g., gain) of the pattern. The geometry can be plotted along with the 3D pattern, if you want, and in that case the grid lines can be helpful. This is a common practice to help people see how the pattern and antenna are oriented relative to each other. Just use a semi-transparent view or cutaway-view (not the full 360).

You can read the gain values from the color bar and the colors in the plot. You can also create 2D polar plots or cartesian plots of the gain vs. various angles, separately from plotting geometries, and this may be useful for more detailed studies of specific values.

You can also choose different plotted quantities for the magnitude (e.g., shape and/or displacement) of the 3D pattern and for the colors of the 3D pattern. Experiment with the settings. But be careful not to create plots that are inherently confusing to yourself and others. Only a few kinds are generally used in the literature. If you look at what others typically use in published papers (such as IEEE journal articles), you will get a good idea of what settings are best and are least confusing.

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Those grid values are associated with the geometry of the antenna and the orientation of the pattern, but not the far-field values (e.g., gain) of the pattern. The geometry can be plotted along with the 3D pattern, if you want, and in that case the grid lines can be helpful. This is a common practice to help people see how the pattern and antenna are oriented relative to each other. Just use a semi-transparent view or cutaway-view (not the full 360). You can read the gain values from the color bar and the colors in the plot. You can also create 2D polar plots or cartesian plots of the gain vs. various angles, separately from plotting geometries, and this may be useful for more detailed studies of specific values. You can also choose different plotted quantities for the magnitude (e.g., shape and/or displacement) of the 3D pattern and for the colors of the 3D pattern. Experiment with the settings. But be careful not to create plots that are inherently confusing to yourself and others. Only a few kinds are generally used in the literature. If you look at what others typically use in published papers (such as IEEE journal articles), you will get a good idea of what settings are best and are least confusing.

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Posted: 5 years ago Feb 20, 2019, 8:07 a.m. EST

Hi Robert, Thanks a lot for this comprehensive answer.

Hi Robert, Thanks a lot for this comprehensive answer.

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