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

## TL;DR

This paper introduces a new low-complexity M-shaped metasurface to reduce signal loss in future 6G wireless systems, especially in indoor millimeter-wave environments.

## Contribution

The novel LCM-RIM design offers a compact, low-power, and scalable solution for mitigating path loss in mmWave communications.

## Key findings

- The LCM-RIM structure enhances received signal strength by up to 15 dB in typical mmWave indoor scenarios.
- The design supports passive beamforming with low hardware complexity and minimal power consumption.

## 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 \documentclass[12pt]{minimal}
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\begin{document}$$0.5\lambda$$\end{document} 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.