Numerical and experimental generated data during project https://doi.org/10.1109/ACCESS.2025.3638980

The dataset was generated during a project aimed at developing a sixteenth mode substrate integrated waveguide (SMSIW) structures designed with right-angled triangle (RT) and scalene triangle (ST), termed RT-SMSIW and ST-SMSIW, respectively, are proposed to design ultra-compact 2 × 1 MIMO antennas. The design concept of SMSIW is based on the subdivision of an eighth mode SIW cavity into dual asymmetric triangular sections, enabling the development of ultra-compact structures. The fundamental modes of these structures are analyzed by deriving boundary conditions and extracting transverse electric (TE) and transverse magnetic (TM) solutions. Initially, two single-element RT-SMSIW and ST-SMSIW-based antennas operating at 3.5 GHz are designed and implemented, followed by the development of 2 × 1 MIMO configurations to explore their potential in multi-port systems. Characteristic Mode Analysis (CMA) is employed to address a significant challenge of achieving high isolation in closely spaced ultra-compact size antenna elements.