SIW-based Hexagonal Slot MIMO Antenna Array for 28 GHz Millimeter-Wave Applications

Abstract

This paper presents a substrate integrated waveguide (SIW) based MIMO antenna array operating at 28 GHz, intended for millimeter-wave (mm-wave) wireless applications. The design entails a hexagonal slot etched into the upper layer of the SIW cavity. Through meticulous optimization of different parameters (the slot's dimensions and its placement within the SIW cavity), a broadside radiation pattern is resulted featuring an impedance bandwidth of 370 MHz (from 27.82 GHz to 28.19 GHz) centered around 28 GHz and a peak gain of 6.10 dBi. To further improve the antenna's performance, a 1×2 antenna array is devised, accompanied by an SIW feed network. This array geometry yields a maximum gain of 8.28 dBi and an impedance bandwidth spanning 0.87 GHz (from 27.59 GHz to 28.46 GHz). To further enhance channel capacity, a 1 × 4 MIMO array is formulated by extending the antenna array. Thus the proposed structure encompasses several notable attributes including large operating gain, and good channel capacity, along with commendable efficiency, and minimal cross-polarization, thereby rendering it well-suited for mm-wave applications. © 2023 IEEE.