A low-complexity M-shaped reconfigurable intelligent meta-surface for mitigating pathloss in wireless systems

Abstract

Abstract Future 6G wireless communication systems require innovative solutions to overcome severe path loss, particularly in the millimeter-wave (mmWave) frequency bands. This study presents a novel Low-Complexity M-shaped Reconfigurable Intelligent Metasurface (LCM-RIM) designed to mitigate path loss in indoor environments. The proposed LCM-RIM features a compact, single-layer unit cell based on a low-loss Rogers substrate, offering a lightweight and cost-effective design suitable for seamless integration into wall-mounted installations in office and conference room settings. Each unit cell incorporates an AlGaAs PIN diode, enabling control at high frequencies and facilitating 1-bit phase modulation with discrete phase shifts of $$0^\circ$$ and $$180^\circ$$ , operating at 24.12 GHz. This configuration supports passive beamforming with low hardware complexity and minimal power consumption. A $$32 \times 32$$ array configuration (1024 elements) with $$0.5\lambda$$ element spacing is used to enhance the gain. The LCM-RIM is employed to enable effective wavefront manipulation and ensure scalability for large-area coverage. To evaluate system-level performance, a numerical path loss model is developed by characterizing the angular gain profile of the LCM-RIM, which follows a Gaussian distribution across reflection angles. The model is validated using MATLAB simulations under various transmitter-receiver distances and angles of incidence. Results indicate that the LCM-RIM structure can enhance received signal strength by up to 15 dB in typical mmWave indoor scenarios. These findings underscore the potential of the proposed LCM-RIM design for practical deployment in future 6G networks, offering an efficient and scalable solution to address mmWave path loss in enclosed environments.