Design and Realization of Wideband 4 - Element Printed MIMO Antenna for X-Ku-Band Satellite and Limited K - Band Short range Applications

This present works focus on increasing the isolation between antennas and enhanced radiation efficiency (
$\eta$
) of the proposed novel four port Multiple - Input Multiple - Output (MIMO) antenna operating in the X-band (8–12GHz), Ku - band (12–18GHz) and limited 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,
$\varepsilon_{\mathrm{r}} =4.4$
, loss tangent,
$\tan\delta=0.02$
, thickness, h = 0.8mm) having a compact size of
$16. 5\text{mm}\times 16.5\text{mm}$
, Proposed MIMO structure is resonating from 7.62 to 23.04GHz at −10dB and is achieved impedance bandwidth (IBW) of 15.42GHz, bandwidth ratio (BR) of 3.02 and fractional bandwidth (FBW) of 100.58 respectively. The proposed antenna achieves improvement in isolation
$(\mathrm{S}_{21})$
greater than 20dB and exhibits high radiation efficiency (
$\eta$
) of 94.63%. Suggested antenna performance can be studied including reflection coefficient
$(\mathrm{S}_{11})$
), voltage standing wave ratio
$(\text{VSWR} < 2)$
), isolation
$(\mathrm{S}_{12})$
), isolation between multi ports, far - field reports, current analysis, Envelope correlation coefficient
$(\text{ECC} < 0.015)$
), diversity gain
$(\text{DG}\sim 10\text{dB})$
), total active reflection coefficient
$(\text{TARC} < 0.3)$
, channel capacity loss
$(\text{CCL} < 0. 2\text{bps}/\text{Hz}$
and Mean effective gain
$(-3\text{dB} < \text{MEG} <-12\text{dB})$
.