Example 6: LHCP Omnidirectional FPV Antenna

This sample report features an omnidirectional circularly polarized antenna, evaluated with our 3D spherical patterns at standard resolution (10 degree steps). The antenna was swept from 5300 to 6300 MHz.

Background: This compact LHCP omnidirectional antenna was designed by the talented Maarten Baert. It is a sophisticatedly simple design with three PCBs on a semi-rigid coax and an SMA connector. This inexpensive antenna was designed for the 5.8 GHz WiFi market, targeting FPV (first person view or remote person view) drone control transceivers. When fitted with a plastic cover, these antennas earn the nickname “lollipop antennas” and are popular among hobbyist RC drone racers.

Results: This antenna performs very well! It has essentially 0 dBi gain in the intended sideways directions, where its axial ratio is around 2 dB. Radiation was verified as LHCP, with a cross-polarization rejection ratio (in the sideways directions) of close to 20 dB. Realized radiation efficiency is 78% at 5.8 GHz. Impressive for an C band antenna made with inexpensive FR4 PCB material. Our test report includes graphs of CP gains (RHCP, LHCP, and magnitude) vs frequency, as well as our interactive variable frequency polar plots (sampled below). As always, all data is provided in Excel spreadsheet format, allowing for additional plots and post-analysis. The results spreadsheet can be downloaded HERE.