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Neamah, Al Sabbagh, & Al-Rizzo | 117

The TARC is a crucial metric in calculating the interference V. CONCLUSION
or mutual coupling between MIMO antenna ports. It is
possible to calculate the TARC for two-port MIMO antennas Two ports S-UWB multiple-input multiple-output
by considering the relationships between S11/S22 and (MIMO) antennas based on polarization diversity have been
S21/S12. A TARC value below 0 dB is desired with an proposed for modern communications. The antenna is
uncorrelated MIMO antenna system. TARC can be designed to function at frequency bands ranging from 3.6 to
calculated by Equation (7) [28]. 40 GHz, with isolation values more than 20 dB throughout
the working frequency band. The single element is modified
TARC = (S11 + S12 )2 + (S 22 + S 21)2 (7) to resemble a sector-shaped monopole SSM patch antenna
2 excited by the CPW feed technique and rotated with respect
to its center. The MIMO array is aligned as orthogonal and
Figure 13 shows the calculated TARC. As shown in figure investigated to perform self-decoupling with high isolation
without using any structure. Common ground is proposed as
13, the TARC is below -6 dB overall band response, which is an L-shape, which makes this MIMO antenna practical. The
simulated design is achieved using CST software, modelled
consistent with the MIMO condition. on an FR-4 substrate with a 4.3 dielectric constant. The
overall array dimensions are 45×23×1.6 mm3. The MIMO
IV. RESULTS COMPARISON metrics such as ECC, DG, TARC and MEG have been
evaluated and give good MIMO performance. Simulation
Table 2 compares two-port orthogonal 1×2 MIMO antennas results within the intended operating ranges demonstrate that
already reported accordingly. One can see from the table that the recommended structure can be utilized for modern
the overall results of our design are eminent either by communications.
bandwidth, gain, ECC, dimensions or isolation. However,
the references are introduced in some with high isolation or CONFLICT OF INTEREST
low ECC, their limit either by dimensions or by design
complexity. This comparison shows that our design besides The authors have no conflict of relevant interest to this
having a simple design, the proposed MIMO antenna has article.
high isolation, a good gain, and a low ECC.
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