A Low-Profile Pin-Loaded Patch Antenna Array with 2-D Wide-Angle Beam Scanning Capability

This paper presents a low-profile pin-loaded patch antenna array with 2-D wide-angle beam scanning capability. The radiation parts of the proposed array are designed on $20-\mathrm{mil}-$ thick ($0.04 \lambda_{0}$ at 24 GHz) PCB substrate and the element spacings are $6 \mathrm{~mm}\left(0.48 \lambda_{0}\right.$ at 24 GHz). Parasitic patches are inserted within the array to increase the beam-width of the antenna element, and all patches are loaded with short pins to suppress the scanning blindness at large angles. Two $1 \times 8$ arrays scanning at E-plane and H-plane respectively are fabricated. Simulated results show that the two arrays match well within 24 GHz to 24.5 GHz with peak realized gain of $\mathbf{1 2. 5} \mathbf{~ d B i}$ to $\mathbf{1 3. 5} \mathbf{~ d B i}$. Measured beam scanning performances at 24 GHz show that the proposed design can achieve less than 3-dB gain loss within -50° to 60° at E-plane and 55° to 60° at H-plane.