A 2 × 1 orthogonal circularly polarized multiple‐input‐multiple‐output (MIMO) antenna is presented at wireless 5G (3.3–4.2 GHz) and 5.9 GHz vehicle‐to‐everything (V2X) application bands. The proposed antenna obtains circular polarization with the incorporation of inserting Γ‐shaped stripline to the ground and asymmetric ground structure. The MIMO antenna exhibits impedance bandwidth of 3.17 GHz in the band of 3.15–6.32 GHz, and 3 dB axial ratio bandwidth of 3.3 GHz in the band of 2.85–6.15 GHz. The design radiates RHCP and LHCP in both directions due to the arrangement of MIMO unit cells in a mirrored fashion. The inter‐port isolation is greater than 20 dB and achieves up to 30 dB within the required band due to orthogonal circular polarizations. A prototype is fabricated on a flexible polyimide substrate and achieved envelope correlation coefficient lower than 0.02, diversity gain almost 10 dB, and channel capacity loss of less than 0.12 b/s/Hz in the operating band. To analyze the effect of the car body on the radiation characteristics, the MIMO antenna is sited on the car side view mirror and roof‐top using the Ansys savant tool. These investigations confirm that the antenna is suitable for wireless and vehicular safety applications.
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