UWB Low-Profile Tightly Coupled Dipole Array

An ultra-wideband (UWB) low profile phased array antenna based on tightly coupled dipole array (TCDA) is proposed. In particular, a gradient line balun is integrated into each cell and a dielectric wide angle impedance matching (WAIM) layer is used to improve the scanning performance of the array. Simulation results show that the antenna unit can achieve 9:1 frequency bandwidth (when the active VSWR<3.5) in infinite period environment. Both E- and H-plane can be scanned to 45°. A 10×10 finite-scale array is fabricated and measured in microwave anechoic chamber, a beam scan range of 45° was achieved for E- and H-plane, and the measured VSWR<3.0 within 9 octaves of bandwidth is achieved resorting to the phase optimization.