Dual-Circularly Polarized Conical-Beam Microstrip Antenna

A dual-circularly polarized (CP) microstrip antenna with conical-beam radiation is presented in this letter. The antenna is excited at the second-order mode to generate the conical radiation pattern and is fed by a hybrid coupler to obtain the dual-CP operation, which shows a stable performance with varisized metal reflectors. The measured results are consistent with the simulated ones in terms of good dual-CP conical patterns, which verified the effectiveness of the proposed design. All these features make the proposed antenna very suitable for vehicle-mounted satellite communication applications.