This sample report features the embedded antenna of the popular Raspberry Pi 3B+, evaluated with our 3D polar patterns at high resolution (5 degree steps). The antenna was swept from 700 MHz to 18.5 GHz in 251 steps.
Background: This embedded antenna was designed by Proant AB, and replaces the dielectric SMT chip antenna used on previous “Pi’s”. The design is a planar resonant cavity using two sets of SMT capacitors to setup resonances in the 2450 and 5800 MHz WiFi ISM bands.
While small antennas are convenient and often inexpensive, they compromise performance for their size trade-off. This example antenna evaluation shows the actual radiation efficiency vs frequency for this tiny antenna, as well as it’s 3D gain patterns. Since the test results are swept from 2 to 7 GHz, we also present a downloadable interactive plot.
Results: Testing showed the radiation efficiency in the 2.45 GHz WiFi band is quite good with an average gain of -2 dBi or 60%. In the 5.5 GHz WiFi band this drops to about -3 dBi or 50% efficiency. In our experience, these are both very good for such a small and inexpensive antenna. As always, all data is provided in Excel spreadsheet format, allowing for additional plots and post-analysis. The results spreadsheet can be downloaded HERE.
Due to the large file size, the HTML interactive 3D plot is available to download from HERE … un-zip it and open it in your browser.
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