The Design of A 3–18GHz Tightly Coupled Dipole Array with An FSS Superstrate

This paper presents a design for ultra-wideband tightly coupled dipole array (TCDA) with a Marchand balun and a printed frequency selective surface (FSS) for wide angle scanning. The simulation results show that the infinite array achieves 6:1 bandwidth (3-18GHz) with VSWR<;2.5 in the broadside while scanning up to ±45° in the E and H planes for VSWR<;3, <; -20dB cross-polarization. The FSS superstrate replaces the bulky dielectric layer, leading to a low profile and low weight structure. In comparison to strip feed line, the tapered micro-strip feed line makes the model easier to fabricate at high frequency.