A Low-Complexity M-Shaped Reconfigurable Intelligent Metasurface for Mitigating Pathloss in Wireless Systems

The 6G wireless communication systems demand innovative solutions to overcome severe path loss challenges, especially in mm-wave applications. This paper introduces a low-complexity, M-shaped Reconfigurable Intelligent Meta-surface (LCM-RIM) designed for indoor applications, such as wall-mounted installations in office environments. Our proposed design employs a compact 1-bit meta-surface, realized as a 32 × 32 unit cell array with 1024 phase shift states operating at 24.12 GHz, ensuring an optimal size of 0.5 λ for effective signal conveyance and optimized signal reflection and coverage. We integrate AlGaAs PIN diodes for control, which mitigate mm-wave signal attenuation. This work presents an improved path loss model for RIM-aided wireless communications, including electromagnetic factors such as LCM-RIM unit cell gain patterns and effective received power. A MATLAB-based model is presented to validate the LCM-RIM design for indoor 6G communications, demonstrating that the M-shaped meta-surface can enhance mmWave signals by approximately 15dB. This result offers a more accurate performance evaluation of RIM-assisted in 6G networks.