Full-Metal Dual-Polarized Phased Array Antenna With Large Element Spacing

In this letter, a full-metal ultrawideband (UWB) phased array antenna with large element spacing is proposed. Two metal blocks are loaded to increase the capacitively coupling, which can broaden the low-frequency bandwidth. Additionally, an equivalent rectangular resonator model is introduced to describe the resonance that affects the high-frequency bandwidth. Subsequently, the high-frequency resonance is shifted from 10.9 to 11.6 GHz by loading a perturbational metal column block on the ground. As a result, the element spacing of the antenna can be broadened as 0.533 × 0.533λ
_10.65GHz
²
. Consequently, the designed antenna has a reduction of at least 6.6% in the number of required expensive transmit/receive (T/R) modules compared with other antennas. Thus, the cost can be noticeably reduced. Finally, the proposed UWB array aperture demonstrates operation from 2 to 10.65 GHz, with active voltage standing wave ratios below 3 for ±60° scans in the E and H planes without scan blindness. To validate the design, a prototype of 10 × 9 array is manufactured through precision-machining and measured. Simulations and measurements show good agreement.