Novel on-Wafer mm wave MIMO Antenna for JCAS of CT Scanners and Ring Resonator for Assessing Polyimide Properties at 60 Ghz

This paper presents an on-wafer dual-port multiple-input—multiple-output (MIMO) antenna for joint communications and sensing (JCAS) of new computed tomography (CT) scanner-based medical applications in the 60 gigahertz (GHz) millimeter wave (mmW) spectrum. The proposed antenna yields a wide -10 decibel (dB) impedance bandwidth (I-BW) of 8.4 GHz from 55.8–64.2 GHz by combining radiating elements with low and high impedance. A partial ground plane was deployed to produce a noteworthy quasi-omnidirectional realized gain ($G_{r}$) of 6.11 dB isotropic (dBi) and a fairly elevated total efficiency $\left(\eta_{t}\right)$ of 79.6$. Furthermore, reasonable antenna isolation $\left(\vert S_{21}\vert \right)$ of >12 dB was ascertained while engaging a compact area of $5.79 \times 8 {\lambda_{0}}^{2}$ and a low-profile of $0.1526 \lambda_{0}$, where $\lambda_{0}$ indicates free-space wavelength at 60 GHz. This paper also introduces a millimeter wave ring resonator (mmW - RR) design that is capable of determining the relative permittivity ($\epsilon_{r}$) of polyimide (PI) wafer at 60 GHz.