Polarized Reconfigurable Decoupled MIMO Patch Antenna Using Characteristic Mode Analysis

This paper uses characteristic mode analysis to design a low-profile, polarization reconfigurable MIMO microstrip patch antenna. The proposed antenna can switch at +45° polarization and -45° polarization by loading liquid metal. Characteristic mode analysis is used to analyze the physical mechanism of loading excitation and decoupling. The antenna gain at the center frequency (4.18 GHz) is 7.75 dBi, and the port coupling is less than -21 dB. The designed antenna has the advantages of low profile, reconfigurable polarization, and self-decoupling. The proposed antenna can be applied to various practical MIMO systems.