LAUSR

In this paper, we propose a compact four-port dual-band MIMO antenna with suppressed higher order modes (HOMs). First, complementary split ring resonator (CSRR) loading is used on a square microstrip antenna to achieve simultaneous miniaturization and dual-band response. Next, the HOMs in the proposed CSRR loaded MIMO configuration are analysed using equivalent circuit model as well as surface current distribution plots. By placing a single shorting post close to antenna center line, these HOMs of the four-port dual-band MIMO antenna are then suppressed, while maintaining satisfactory mutual coupling (< –11 dB) and impedance matching (< –15 dB) performance in the operating band. Furthermore, simulated and measured values of total active reflection coefficient (TARC), envelop correlation coefficient (ECC) and channel capacity loss (CCL) are within the desired levels of –10 dB, 0.5 and 0.5 bits/s/Hz respectively, signifying good diversity performance of the proposed MIMO antenna.