Low Mutual Coupling with High Efficiency Circularly Polarized MIMO DRA for On-chip mm-Wave Applications

A low mutually coupled multiple-input multiple-output (MIMO) antenna is designed for on-chip millimetre-wave (mm-Wave) application. Two circularly polarized (CP) cylindrical dielectric resonator antennas (CDRA) with polarization diversity are placed over a double substrate silicon layer. Herein, a simple decoupling approach is applied to inhibit mutual coupling by introducing a metal plate in the substrate between the two DRAs. According to the simulation results, the inserted metallic plate improved isolation by 4–5 dB in the desired CP bandwidth. This is achieved while maintaining excellent radiation efficiency and gain, making the suggested antenna appropriate for mm-wave on-chip MIMO applications.