Sub-6 GHz Eight-Port 3-D Vehicular Antenna

This paper presents an 8-port 3-D MIMO diversity antenna designed for sub-6 GHz band. It shows $-\mathbf{10dB}$ impedance bandwidth over the frequency of 3.2-6 GHz. The size of the unit cell is 30 $\times 30\times 0.76\text{mm}^{3}$ and it is developed on Rogers 5880 substrate. The unit element is augmented into 8 port MIMO antenna. The MIMO antenna's footprint is $66\times 66$ mm 2. The elements are placed right-angled to each other for better isolation. It also helps in achieving polarization diversity with six polarization vectors. The isolation is found to be greater than 20 dB. The peak efficiency and gain are respectively 98 % and 3.3 dBi. The MIMO characteristic study results in TARC value less than $-\mathbf{10\ dB}$, CCL value less than 0.15 bits/s/Hz, ECC $\boldsymbol{ < 0.003}$, and DG $\boldsymbol{ > 9.85}$. The stability of the antenna in automotive environment is checked using housing effects.