Simulated four-port MIMO antenna stretches from mmWave to sub-THz

Engineers have proposed a simulation-based design for a compact four-port 2×2 MIMO antenna that spans an unusually wide radio range—from millimetre-wave frequencies to the sub-THz region. Published in Frontiers in Antennas and Propagation, the work describes evolving a circular patch into a petal-like radiator formed by five overlapping, rotated elliptical sections, then scaling it into a four-element array that fits in a fingertip-sized footprint. Using CST Studio Suite, conventional reflection coefficients stayed below −10 dB from 13.6 GHz to 151.91 GHz, yielding an impedance bandwidth of 138.31 GHz and ~167.1% fractional bandwidth. Transmission coefficients remained mostly below −20 dB. Parametric geometry tuning achieved wide matching and low inter-port coupling without extra decoupling structures. Peak realized gain hit 11.87 dBi, and simulated radiation efficiency stayed above ~90% to about 120 GHz.