A Wideband, Low-Profile Log-Periodic Monopole Array With End-Fire Scanning Beams

In this letter, we propose a wideband, low-profile phased array with vertically polarized end-fire radiation patterns. The array consists of four identical log-periodic top-hat monopole antennas (LPTMAs) and could be completely embedded within a shallow cavity for sight invisible integrated installation on metallic platforms. Simulation results show that the proposed array operates over a wide frequency band of 1.0-3.0 GHz for active voltage standing wave ratio <;2.0. It also possesses end-fire radiation patterns with ±45° beam scanning capability in the horizontal plane. Prototypes of the proposed LPTMA and a uniformly spaced linear array (1 × 4) are fabricated and validated in experiments. Measured results are in a good agreement with the simulation results. The measured results demonstrate that the proposed end-fire scanning array is attractive for applications that require wideband beam scanning, excellent aerodynamic, and stealth performances.