Compact Dual Band Substrate Integrated Waveguide MIMO Antenna for X-Band Application

Abstract

This article introduces a compact, dual-band, eight-port Multiple Input Multiple Output (MIMO) stacking antenna integrated with Substrate Integrated Waveguide (SIW) and a common ground. The antenna operates in the 9.2-9.5 GHz and 11.5-12.25 GHz frequency bands. Its configuration consists of four identical, coaxial fed annular ring radiators mounted on an FR4 substrate (40x40x4 mm³). To enhance the performance of the eight-port MIMO antenna, a feed structure is positioned above the radiator structure. The SIW-integrated MIMO antenna demonstrates excellent isolation (>15 dB), high gain (8 dB and 6.6 dB), and favourable diversity parameters. The design demonstrates a minimal Envelope Correlation Coefficient (ECC) of 0.10 and a substantial diversity gain (DG) of 9.96 dB, demonstrating its potential to guarantee strong diversity reception and improve communication dependability, especially in challenging situations.