Design of Low - Profile Four Port Linear Configured Wideband MIMO Antenna for C-X-Ku-K-band Applications

This present works focus on increasing the isolation between antennas and enhanced radiation efficiency (η) of the proposed novel four port Multiple – Input Multiple – Output (MIMO) antenna operating in the C – band (4 – 8GHz), X – band (8 - 12GHz), Ku – band (12 – 18GHz) and K – band (18 - 26.5GHz) applications. The design is fed by tapered structure and has been printed on FR – 4 epoxy substrate material (dielectric constant, ε
r
= 4.4, loss tangent, tanδ = 0.02, thickness, h = 0.8mm) having a compact size of 24mm x 10.5mm. Proposed linear configured MIMO structure is resonating from 6.14 to 23.16GHz at -10dB and is achieved impedance bandwidth (IBW) of 17.02GHz, bandwidth ratio (BR) of 3.77 and fractional bandwidth (FBW) of 116.17 respectively. The proposed antenna achieves improvement in isolation (S
21
) greater than 25dB and exhibits high radiation efficiency (η) of 98.04%. Suggested antenna performance can be studied including reflection coefficient (S
11
), voltage standing wave ratio (VSWR < 2), isolation (S
12
), isolation between multi ports, far – field reports, current analysis, Envelope correlation coefficient (ECC < 0.02), diversity gain (DG ~ 10dB), total active reflection coefficient (TARC < 0.3), channel capacity loss (CCL < 0.25bps/Hz) and Mean effective gain (-2.4dB < MEG < -12.8dB).