A compact four element CSRR-loaded antenna for dual band pattern diversity MIMO applications

In this paper, a four element compact MIMO antenna system is proposed for dual-band (GSM/WLAN/WiFi/LTE) applications. Dual-band antenna characteristics is obtained by loading L-shaped monopoles with complementary split ring resonators (CSRR), which produce an antenna resonance in addition to the reference monopole mode. Inter-element isolation of more than 15 dB is achieved in both the operating bands. The four element MIMO configuration exhibits pattern diversity in both the bands due to the directional radiation characteristics of the dual-band antenna element. The proposed antenna has satisfactory performance in terms of MIMO parameters as envelope correlation coefficient (ECC) < 0.5, mean effective gain (MEG) ratio (MEGi/MEGj) ≈ 1, total active reflection coefficient (TARC) < −10 dB and average channel capacity loss (CCL) < 0.5 bits/s/Hz are obtained in both the working bands. Experimental results on the fabricated MIMO antenna prototype confirms the validity of the proposed design concept.