A Compact Planar Conical Beam Array Antenna

A novel compact planar conical beam antenna with high gain, low side lobe level (SLL), enhanced bandwidth, and stable beam pointing angle within the working bandwidth is proposed. With a low profile of 0.11 λ
₀
, it consists of a multiport radiator formed by three annular radiation elements and a feeding network. To facilitate the multiport array radiator design, a method to quickly get its overall reflection coefficient is developed, and an element-level pattern diversity (ELPD) technique is applied in the design. The proposed antenna with a feeding network has achieved an impedance bandwidth of 13.2% (4.67 ~ 5.33 GHz), a peak gain of 14.1 dBi, and a SLL of -21 dB at the center frequency of 5 GHz.