A 12.5:1 Bandwidth Dual-Polarized Tightly Coupled Dipole Phased Array with Compact Balun

Abstract

This paper presents an ultra-wideband dual-polarized tightly coupled dipole array (TCDA) with compact perforated Marchand balun. Equivalent circuit model (ECM) is employed to determine preliminary design parameters for TCDA. In order to feed the array, a wideband and compact perforated Marchand balun is developed based on its ECM. A resistive loop is carefully designed and integrated in the array to further improve the impedance bandwidth of the TCDA. The phased array gives a 12.5:1 bandwidth (0.8-10 GHz, VSWR < 2.7), and ±45° scanning angles in both of the E-plane and H-plane. In addition, it is observed that the array delivers a 10.5:1 (0.86-9 GHz, VSWR < 3.3) bandwidth and a scanning range of ±60° in both of the E-plane and H-plane. The cross polarization level of the array in both of the two polarizations is below -20 dB, which outperforms those of reported TCDAs designed with the state of the art.