Stub-Loaded Reactive Decoupling Network for Two-Element Array Using Even–Odd Analysis

A stub-loaded reactive decoupling network is investigated in this letter for two-element closely spaced array. The proposed topology, consisting of a pair of connecting lines and a T-shaped neutralized section, is developed based on the even/odd-mode analysis. The proposed scheme is able to deal with the matching and decoupling requirements in the even and odd modes separately and, hence, able to achieve overall good impedance matching and excellent port isolation simultaneously for an arbitrary two-element closely spaced array. The design concept, formulation, and experimental results will be introduced.