Wideband Wide-scanning TCDA With Resistive-Frequency-Selective Surface and KlopfensteinTapered Balun

A wideband tightly coupled dipole array (TCDA) with resistive frequency selective surface (RFSS) fed by a Klopfenstein taper balun is proposed. A tooth-shaped slit is etched on the arms of the dipole, increasing the equivalent capacitance of the antenna and offsetting the inductive component of the floor. The impedance matching of the antenna at low frequency is improved. In addition, an RFSS is placed between the antenna and floor to filter out scanning blind spots caused by reflected waves at 3.2GHz. Moreover, the Klopfenstein-taper balun with a wideband-matching is used as the balanced feed structure. The infinite array and a 1*10 array are simulated. The Active VSWR at broadside of the array is $1.77 \mathrm{GHz}-7.94 \mathrm{GHz}$ under a scanning angle of ± 60° can be realized.