Low profile four-port super-wideband multiple-input-multipleoutput antenna with triple band rejection characteristics

摘要

A quad-port planar multiple-input-multiple-output (MIMO) antenna possessing super-wideband (SWB) operational features and triple-band rejection characteristics is designed. The proposed MIMO configuration consists of four modified-elliptical-self-complementary-antenna (MESCA) elements, which are excited by tapered co-planar waveguide (TCPW) feed lines. A radiator-matched complementary slot is present in the ground conductor patch of each MESCA element. The proposed MIMO antenna exhibits a bandwidth ratio of 36:1 (|S-11| < -10 dB; 0.97-35 GHz). Further, a step-like slit-resonator is etched in the radiator to eliminate interferences at 3.5 GHz. A hexagonal shaped complementary split ring resonator (CSRR) is also loaded on the MESCA radiator to remove interferences at 5.5 and 8.5 GHz. The MIMO antenna is fabricated on FR-4 substrate of size 63 x 63 mm(2) and experimental results are found in good agreement with the simulated results. The MIMO antenna exhibits inter-element isolation >17 dB and envelope correlation coefficient (ECC) <0.01 at all the four ports.