High-Isolation Multilayered SIW-Based MIMO Antenna for Next-Generation Terahertz Applications

Abstract

This paper presents a four-port multiple-input-multiple-output (MIMO) antenna, which has dimensions of 108 μm × 104 μm × 2.84 μm, with improved isolation and operating across multiple terahertz (THz) frequency bands. The antenna design supports triple-band operation at resonant frequencies of 6.7 THz, 7.8 THz, and 9.1 THz, and to improve isolation, vias are loaded around the resonating patch. The MIMO antenna experiences mutual coupling issues at THz frequencies, which is due to shorter wavelengths. The substrate integrated waveguide (SIW) ensures excellent signal transmission while reducing unwanted coupling between antenna elements. Also, multi-layering is used by placing a rectangular truncated patch between two substrates to enhance the gain, resulting in a peak gain of 10.8 dBi. The proposed design is a viable option for use in THz MIMO antenna systems that require improved isolation and gain. It may be suitable for multiband THz communications, including wireless body area networks, sensing and imaging, and the Internet of things applications.