Low-profile ultra-wideband array design based on dielectric layer loading

Abstract

In the paper, a new ultra-wideband tightly coupled antenna array (TCA) is designed. The array unit is mainly based on the traditional Vivaldi antenna structure, to which trapezoidal slots are added and metal vias are used to extend the radiating arms, thus forming a flat plate coupling capacitor to reduce the overall profile height of the antenna. The wide foot matching layer is placed on top of the antenna, and T-slots are added on both sides of the Vivaldi opening to increase the resonance point and widen the bandwidth. This unit is formed into an array, and the array takes the form of a uniform planar array. Based on the above improved dielectric layer loading low-profile array can achieve VSWR<2.5 at 3~18GHz with 15mm profile height, and also can achieve high radiation efficiency, which is >85% in the full band.