Wideband Modeling and Beamforming for Beyond Diagonal Reconfigurable Intelligent Surfaces (2403.12893v1)
Abstract: This work studies the wideband modeling and beamforming design of beyond diagonal reconfigurable intelligent surface (BD-RIS), which generalizes and goes beyond conventional RIS with diagonal phase shift matrices to achieve enhanced channel gain. Specifically, we investigate the response of BD-RIS in wideband systems by going back to its hardware circuit realizations. We propose a novel wideband model which has simple expressions while capturing the response variations of BD-RIS for signals with different frequencies. With this wideband model, we propose a BD-RIS design algorithm for an orthogonal frequency division multiplexing system to maximize the average rate over all subcarriers. Finally, we provide simulation results to evaluate the performance of the proposed design and show the importance of wideband modeling for BD-RIS.
- “Intelligent reflecting surface-aided wireless communications: A tutorial,” IEEE Trans. Commun., vol. 69, no. 5, pp. 3313–3351, 2021.
- “Reconfigurable intelligent surfaces 2.0: Beyond diagonal phase shift matrices,” IEEE Commun. Mag., vol. 62, no. 3, pp. 102–108, 2024.
- “Modeling and architecture design of reconfigurable intelligent surfaces using scattering parameter network analysis,” IEEE Trans. Wireless Commun., vol. 21, no. 2, pp. 1229–1243, 2021.
- “Beyond diagonal reconfigurable intelligent surfaces utilizing graph theory: Modeling, architecture design, and optimization,” IEEE Trans. Wireless Commun., 2024.
- “Intelligent omni-surfaces for full-dimensional wireless communications: Principles, technology, and implementation,” IEEE Commun. Mag., vol. 60, no. 2, pp. 39–45, 2022.
- “A universal framework for multiport network analysis of reconfigurable intelligent surfaces,” arXiv:2311.10561, 2023.
- “Maximizing spectral and energy efficiency in multi-user MIMO OFDM systems with RIS and hardware impairment,” arXiv preprint arXiv:2401.11921, 2024.
- “Intelligent reflecting surface enhanced wideband MIMO-OFDM communications: From practical model to reflection optimization,” IEEE Trans. Commun., vol. 69, no. 7, pp. 4807–4820, 2021.
- “A general wideband non-stationary stochastic channel model for intelligent reflecting surface-assisted MIMO communications,” IEEE Trans. Wireless Commun., vol. 20, no. 8, pp. 5314–5328, 2021.
- “A joint precoding framework for wideband reconfigurable intelligent surface-aided cell-free network,” IEEE Trans. Signal Process., vol. 69, pp. 4085–4101, 2021.
- “Intelligent reflecting surface-enhanced OFDM: Channel estimation and reflection optimization,” IEEE Wireless Commun. Lett., vol. 9, no. 4, pp. 518–522, 2019.
- Surrogate-based modeling and optimization, Springer, 2013.
- “Localized and distributed beyond diagonal reconfigurable intelligent surfaces with lossy interconnections: Modeling and optimization,” arXiv:2402.05881, 2024.