Holistic Interaction Suppression in Dual-Band Antenna Array

This paper introduces holistic approaches to address the challenges faced by a typical dual-band side-by-side antenna array arrangement, where antennas with close spacing suffer from significant interactions leading to degradation in radiation patterns and port-to-port isolations. The proposed methods utilize three multifunctional loading structures, including a 2.5-dimensional (2.5-D) cloak, defected ground structure (DGS), and resonance shifter (RS), to simultaneously suppress both cross-band scattering and coupling. These structures effectively mitigate the cross-band interactions between the low-band (LB) and high-band (HB) antennas. Moreover, the 2.5-D cloak and RS also contribute to in-band coupling suppression and improved isolation between adjacent HB antennas. In addition, all these structures can be designed on the same substrate as the original antennas, eliminating the need for additional layers. This feature not only ensures cost-effectiveness but also facilitates the implementation process, making it easy to integrate the proposed techniques into existing antenna systems.