A compact 2×1 multiple input multiple output (MIMO) antenna system is designed to operate in the LTE band 40 (2.3-2.4) GHz. The proposed antenna consists of two circular patches fed using microstrip line. The antenna was initially designed to resonate at 5 GHz. Size reduction of 55.17% compared to conventional patch antenna is obtained after the inclusion of circular complementary split ring resonator (CSRR) in the ground plane. The resonating frequency was shifted to 2.34 GHz, there by the board size is compact (50×25×1.6 mm3). The designed antenna covers a bandwidth of 2.3 to 2.374 GHz with a maximum return loss of -27 dB at 2.34 GHz and isolation of -33.5 dB between the ports. The simulated correlation coefficient is approximately zero, and the total active reflection coefficient is 0.142 at the resonating frequency which are within the acceptable limits. The realized gain for the antenna is -8.9 dB.
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