C-band MIMO antenna with isolation and gain enhancement for MIMO radar applications

A miniaturized C-band multiple-input-multiple-output (MIMO) antenna with good isolation and gain enhancement is investigated. Based on the reaction theorem, an equivalent magnetic current is introduced to decrease the effect caused by the electric current source, contributing to wideband isolation enhancement. Such a miniaturized antenna usually suffers from gain deterioration. Therefore, a three stacked superstrates with the metal strips are proposed for wideband gain enhancement. Good S₁₁ (<; -10dB), S₂₁ (<; -15dB) and gain enhancement (4.3 dB at the most) for 4-8 GHz are achieved.