A Wideband Circularly Polarized Patch Antenna with Conical Radiation Pattern

A circularly polarized conical-beam patch antenna that employs a hybrid feeding mechanism for wideband operation is presented in this paper. It is implemented through using a pair of L-probes and apertures, which are connected by the feeding network, to excite the circular patch in orthogonal directions. The patch is supported by two plastic posts of 0.084 lambda₀ height in the air, where lambda₀ is the free space wavelength at 2.53 GHz. This antenna possesses an impedance bandwidth of 28.2% (SWR < 1.5) and an axial ratio bandwidth (AR < 3 dB) of 28.3%. Also, it has left hand circularly polarized (LHCP) conical patterns with the peaks located at around thetas = plusmn33⁰ over these bandwidths. Moreover, its 3-dB gain bandwidth and peak gain are 32.4% and 5.5 dBi, respectively.