A Wideband Single-Feed Circularly Polarized Stacked Patch Antenna

We present a circularly polarized single-feed stacked patch antenna with wide axial ratio bandwidth, suitable for both coaxial probe feeding and coplanar microstrip feeding. The antenna is composed of two patches with truncated corners connected together using four pins. The circularly polarized antenna has been designed using CST Studio Suite in the upper part of the UHF frequency band. A prototype has been fabricated using low-cost 3D-printing manufacturing technology. In this regard, both the dielectric substrate and the support for the stacked patches have been realized with a 3D-printed Polylactic Acid. Measured results provide a 34% −10 dB reflection coefficient bandwidth (between 2.14 and 3.03 GHz) and a 3 dB axial ratio bandwidth of 25% (between 2.31 and 2.97 GHz), with a flat gain in the overlapped (axial ratio-reflection coefficient) bandwidth that coincides with the axial ratio bandwidth and a peak gain of 8.5 dBic.