A Compact Triband Quad-Element MIMO Antenna Using SRR Ring for High Isolation

• Published in: IEEE antennas and wireless propagation letters 2017, Vol.16, p.1409-1412
• Main Authors: Ramachandran, Anitha, Mathew, Sumitha, Rajan, Vivek, Kesavath, Vasudevan
• Format: Article
• Language: English
• Subjects: Antenna measurements; Bandwidth; Correlation coefficients; Couplings; Diversity performance; envelope correlation; Gain; isolation; Loaded antennas; meander-line antenna; MIMO; multiple-input–multiple-output (MIMO); polarization diversity; Resonators; split-ring resonator (SRR)
• ISSN: 1536-1225; 1548-5757
• DOI: 10.1109/LAWP.2016.2640305

A compact multiband four port diversity-based antenna with high isolation between elements is proposed for multiple-input-multiple-output applications. The antenna resonates at following three bands: 1.95-2.5 GHz (covering UMTS, LTE 2300, and 2.4-GHz ISM bands), 3.15-3.85 GHz (covering WiMAX band), and 4.95-6.6 GHz (covering 5.2/5.8-GHz ISM bands). The stub-loaded meander-line antenna is loaded with split-ring resonators arranged in the form of a ring to enhance isolation by 17 dB at 2.4 GHz. All four elements radiate with equal efficiency with measured peak gains of 2.5, 3.7, and 4.4 dBi, respectively, in three bands and have a very low envelope correlation coefficient between elements. The overall size of the compact multiport antenna system is 0.26λ × 0.26λ × 0.01λ with a minimum isolation of 22 dB between its elements. The antenna elements and the isolation enhancement structure are fully planar for an easier integration.