Millimeter-Wave RIS: Hardware Design and System-Level Considerations

Ruiqi Wang; Pinjun Zheng; Yiming Yang; Xiarui Su; Mohammad Vaseem; Anas Chaaban; Md. Jahangir Hossain; Tareq Y. Al-Naffouri; Atif Shamim

arXiv · 2602.23345

Millimeter-Wave RIS: Hardware Design and System-Level Considerations

Ruiqi Wang·Pinjun Zheng·Yiming Yang·Xiarui Su·Mohammad Vaseem·Anas Chaaban·Md. Jahangir Hossain·Tareq Y. Al-Naffouri·Atif Shamim

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Abstract

Reconfigurable intelligent surfaces have emerged as a promising hardware platform for shaping wireless propagation environments at millimeter-wave (mm-Wave) frequencies and beyond. While many existing studies emphasize channel modeling and signal processing, practical RIS deployment is fundamentally governed by hardware design choices and their system-level implications. This paper presents a hardware-centric overview of recent mm-Wave RIS developments, covering wideband realizations, high-resolution phase-quantized designs, fully printed low-cost implementations, optically transparent surfaces, RIS-on-chip solutions, and emerging three-dimensional architectures. Key challenges including mutual coupling, calibration, multi-RIS interaction, and frequency-dependent phase control are discussed to bridge hardware realization with system-level optimization. This overview provides practical design insights and aims to guide future RIS research toward scalable, efficient, and practically deployable intelligent surface architectures.

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Ruiqi Wang, Pinjun Zheng, Yiming Yang, Xiarui Su, Mohammad Vaseem, Anas Chaaban, Md. Jahangir Hossain, Tareq Y. Al-Naffouri, Atif Shamim. 2026-02-26. Millimeter-Wave RIS: Hardware Design and System-Level Considerations. https://arxiv.org/abs/2602.23345

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