A broadband and wide beamwidth dual circularly polarized antenna using crossed bent dipoles

A broadband and wide-beamwidth dual circularly polarized (CP) antenna is presented in this paper. The antenna consists of two bent dipoles placed in a crossed shape. The dipoles are individually fed with signals with quadrature phases from a 3-dB hybrid coupler chip. A metal cavity serving as a reflector is used to produce a unidirectional radiation pattern. Measurements show that the antenna has an impedance bandwidth of 66.2% (0.98-1.95 GHz) for |S
₁₁
|<;-10 dB, an axial-ratio bandwidth (ARBW) of 51.4% (1.03-1.75 GHz) for AR<;3 dB, and a very wide AR beamwidth of over 162° with a maximum AR beamwidth of 260°.