Best Readings
Overview and Fundamentals of BD-RIS
Overview
H. Li, S. Shen, M. Nerini, and B. Clerckx, "Reconfigurable intelligent surfaces 2.0: Beyond diagonal phase shift matrices," IEEE Commun. Mag., 2023.
Fundamentals
S. Shen, B. Clerckx, and R. Murch, "Modeling and architecture design of reconfigurable intelligent surfaces using scattering parameter network analysis," IEEE Trans. Wireless Commun., 2022.
H. Li, S. Shen, and B. Clerckx, "Beyond diagonal reconfigurable intelligent surfaces: From transmitting and reflecting modes to single-, group-, and fully-connected architectures," IEEE Trans. Wireless Commun., 2023.
H. Li, S. Shen, and B. Clerckx, "Beyond diagonal reconfigurable intelligent surfaces: A multi-sector mode enabling highly directional full-space wireless coverage," IEEE J. Sel. Areas Commun., 2023.
M. Nerini, S. Shen, H. Li, and B. Clerckx, "Beyond diagonal reconfigurable intelligent surfaces utilizing graph theory: Modeling, architecture design, and optimization," IEEE Trans. Wireless Commun., 2024.
M. Nerini, and B. Clerckx, "Pareto frontier for the performance-complexity trade-off in beyond diagonal reconfigurable intelligent surfaces," IEEE Commun. Lett., 2023.
More BD-RIS Architectures
Static Architectures
X. Zhou, T. Fang, and Y. Mao, "A novel Q-stem connected architecture for beyond-diagonal reconfigurable intelligent surfaces," arXiv:2411.18480, 2024.
M. Nerini, and B. Clerckx, "Dual-polarized beyond diagonal RIS," arXiv:2412.16097, 2024.
Dynamic Architectures
Q. Li et al., "Reconfigurable intelligent surfaces relying on non-diagonal phase shift matrices," IEEE Trans. Veh. Technol., 2022.
H. Li, S. Shen, and B. Clerckx, "A dynamic grouping strategy for beyond diagonal reconfigurable intelligent surfaces with hybrid transmitting and reflecting mode," IEEE Trans. Veh. Technol., 2023.
Q. Li, M. El-Hajjar, I. Hemadeh, A. Shojaeifard, and L. Hanzo, "Coordinated Reconfigurable Intelligent Surfaces: Non-Diagonal Group-Connected Design," IEEE Trans. Veh. Technol., 2024.
Y. Dong, Q. Li, S. X. Ng, and M. El-Hajjar, "Reconfigurable intelligent surface relying on low-complexity joint sector non-diagonal structure," IEEE Open J. Veh. Technol., 2024.
Non-Reciprocal Architectures
H. Li, and B. Clerckx, "Non-reciprocal beyond diagonal RIS: Multiport network models and performance benefits in full-duplex systems," arXiv:2411.04370, 2024.
J. Xu, H. Wang, R. Liu, J. A. Nossek, and A. L. Swindlehurst, "Non-reciprocal reconfigurable intelligent surfaces," arXiv:2411.15617, 2024.
Z. Liu, H. Li, and B. Clerckx, "Non-reciprocal beyond diagonal RIS: Sum-rate maximization in full-duplex communications," arXiv:2411.18523, 2024.
Optimization and Performance Analysis of BD-RIS
Optimization of BD-RIS
G. Bartoli, A. Abrardo, N. Decarli, D. Dardari, and M. Di Renzo, "Spatial multiplexing in near field MIMO channels with reconfigurable intelligent surfaces," IET Signal Processing, 2023.
M. Nerini, S. Shen, and B. Clerckx, "Closed-form global optimization of beyond diagonal reconfigurable intelligent surfaces," IEEE Trans. Wireless Commun., 2023.
M.-A. Kim, S.-G. Yoo, H.-D. Kim, K.-H. Shin, and H.-K. Song, "Scattering matrix design of reconfigurable intelligent surface based on group connected impedance network in MU-MIMO system," International Conference on Ubiquitous and Future Networks (ICUFN), 2023.
T. Fang, and Y. Mao, "A low-complexity beamforming design for beyond-diagonal RIS aided multi-user networks," IEEE Commun. Lett., 2023.
I. Santamaria, M. Soleymani, E. Jorswieck, and J. Gutierrez, "SNR maximization in beyond diagonal RIS-assisted single and multiple antenna links," IEEE Signal Process. Lett., 2023.
Y. Zhou, Y. Liu, H. Li, Q. Wu, S. Shen, and B. Clerckx, "Optimizing power consumption, energy efficiency and sum-rate using beyond diagonal RIS — A unified approach," IEEE Trans. Wireless Commun., 2023.
M. Nerini, S. Shen, and B. Clerckx, "Static grouping strategy design for beyond diagonal reconfigurable intelligent surfaces," IEEE Commun. Lett., 2024.
W. Sun, S. Sun, T. Shi, X. Su, and R. Liu, "A new model of beyond diagonal reconfigurable intelligent surfaces (BD-RIS) for the corresponding quantization and optimization," IEEE Trans. Wireless Commun., 2024.
I. Santamaria, M. Soleymani, E. Jorswieck, and J. Gutiérrez, "MIMO capacity maximization with beyond-diagonal RIS," IEEE International Workshop on Signal Processing Advances in Wireless Communications (SPAWC), 2024.
E. Björnson, and Ö. T. Demir, "Capacity maximization for MIMO channels assisted by beyond-diagonal RIS," arXiv:2411.18298, 2024.
Z. Wu, and B. Clerckx, "Optimization of beyond diagonal RIS: A universal framework applicable to arbitrary architectures", arXiv:2412.15965, 2024.
C. Zhang, W. U. Khan, A. K. Bashir, A. K. Dutta, A. U. Rehman, and M. M. Al Dabel, "Sum rate maximization for 6G beyond diagonal RIS-assisted multi-cell transportation systems," IEEE Trans. Intell. Transp. Syst., 2025.
X. Zhou, T. Fang., and Y. Mao, "Joint active and passive beamforming optimization for beyond diagonal RIS-aided multi-user communications," IEEE Commun. Lett., 2025.
Optimization of BD-RIS with Machine Learning
R. Cerna Loli, and B. Clerckx, "Meta-learning based optimization for large scale wireless systems," arXiv:2407.01823, 2024.
S. Sobhi-Givi, M. Nouri, H. Behroozi, and Z. Ding, "Joint BS and beyond diagonal RIS beamforming design with DRL methods for mmWave 6G mobile communications," IEEE Wireless Communications and Networking Conference (WCNC), 2024.
Performance Analysis of BD-RIS
M. Samy, A. B. M. Adam, K. Ntontin, H. Al-Hraishawi, S. Chatzinotas, and B. Otteresten, "Enhancing spectral and energy efficiency with multi-sector beyond-diagonal RIS," IEEE International Workshop on Signal Processing Advances in Wireless Communications (SPAWC), 2024.
M. Samy, H. Al-Hraishawi, A. B. M. Adam, K. Ntontin, S. Chatzinotas, and B. Otteresten, "Beyond diagonal RIS-aided networks: Performance analysis and sectorization tradeoff," arXiv:2406.04009, 2024.
Channel Estimation for BD-RIS
H. Li, Y. Zhang, and B. Clerckx, "Channel estimation for beyond diagonal reconfigurable intelligent surfaces with group-connected architectures," IEEE International Workshop on Computational Advances in Multi-Sensor Adaptive Processing (CAMSAP), 2023.
H. Li, S. Shen, Y. Zhang, and B. Clerckx, "Channel estimation and beamforming for beyond diagonal reconfigurable intelligent surfaces," IEEE Trans. Signal Process., 2024.
A. L. F. de Almeida, B. Sokal, H. Li, and B. Clerckx, "Channel estimation for beyond diagonal RIS via tensor decomposition," arXiv:2407.20402, 2024.
N. Ginige, A. S. de Sena, N. H. Mahmood, N. Rajatheva, and M. Latva-aho, "Efficient channel prediction for beyond diagonal RIS-assisted MIMO systems with channel aging," arXiv:2411.17725, 2024.
G. T de Araujo, and A. L. F. de Almeida, "Semi-blind channel estimation for beyond diagonal RIS," arXiv:2412.02824, 2024.
B. Sokal, Fazal-E-Asim, A. L. F. de Almeida, H. Li, and B. Clerckx, "A decoupled channel estimation method for beyond diagonal RIS," arXiv:2412.06683, 2024.
Modeling and Optimization of BD-RIS with Hardware Impairments
Physics-Compliant Modeling of BD-RIS
M. Nerini, S. Shen, H. Li, M. Di Renzo, and B. Clerckx, "A universal framework for multiport network analysis of reconfigurable intelligent surfaces," IEEE Trans. Wireless Commun., 2024.
P. del Hougne, "Physics-compliant diagonal representation of beyond-diagonal RIS," IEEE International Workshop on Signal Processing Advances in Wireless Communications (SPAWC), 2024.
P. del Hougne, "A physics-compliant diagonal representation for wireless channels parametrized by beyond-diagonal reconfigurable intelligent surfaces," arXiv:2409.20509, 2024.
D. Wijekoon, A. Mezghani, G. C. Alexandropoulos, and E. Hossain, "Physically-consistent modeling and optimization of non-local RIS-assisted multi-user MIMO communication systems," arXiv:2406.05617, 2024.
M. Nerini, G. Gradoni, and B. Clerckx, "Physics-compliant modeling and scaling laws of multi-RIS aided MIMO systems," arXiv:2411.06309, 2024.
BD-RIS with Lossy Interconnections
M. Nerini, G. Ghiaasi, and B. Clerckx, "Localized and distributed beyond diagonal reconfigurable intelligent surfaces with lossy interconnections: Modeling and optimization" arXiv:2402.05881, 2024.
BD-RIS for Wideband Communications
A. S. de Sena, M. Rasti, N. H. Mahmood, and M. Latva-aho, "Beyond diagonal RIS for multi-band multi-cell MIMO networks: A practical frequency-dependent model and performance analysis," arXiv:2401.06475, 2024.
M. Soleymani, I. Santamaria, A. Sezgin, and E. Jorswieck, "Maximizing spectral and energy efficiency in multi-user MIMO OFDM systems with RIS and hardware impairment," arXiv:2401.11921, 2024.
H. Li, M. Nerini, S. Shen, and B. Clerckx, "Wideband modeling and beamforming for beyond diagonal reconfigurable intelligent surfaces," IEEE International Workshop on Signal Processing Advances in Wireless Communications (SPAWC), 2024.
H. Li, M. Nerini, S. Shen, and B. Clerckx, "Beyond diagonal reconfigurable intelligent surfaces in wideband OFDM communications: Circuit-based modeling and optimization," arXiv:2405.07297, 2024.
O. T. Demir, and E. Bjornson, "Wideband channel capacity maximization with beyond diagonal RIS reflection matrices," IEEE Wireless Commun. Lett., 2024.
K. D. Katsanos, P. Di Lorenzo, and G. C. Alexandropoulos, "The interference broadcast channel with reconfigurable intelligent surfaces: A cooperative sum-rate maximization approach," IEEE International Workshop on Signal Processing Advances in Wireless Communications (SPAWC), 2024.
K. D. Katsanos, P. Di Lorenzo, and G. C. Alexandropoulos, "Multi-RIS-empowered multiple access: A distributed sum-rate maximization approach," IEEE J. Sel. Top. Signal Process., 2024.
BD-RIS with Mutual Coupling
H. Li, S. Shen, M. Nerini, M. Di Renzo, and B. Clerckx, "Beyond diagonal reconfigurable intelligent surfaces with mutual coupling: Modeling and optimization," IEEE Commun. Lett., 2024.
M. Nerini, H. Li, and B. Clerckx, "Global optimal closed-form solutions for intelligent surfaces with mutual coupling: Is mutual coupling detrimental or beneficial?," arXiv:2411.04949, 2024.
D. Semmler, J. A. Nossek, M. Joham, B. Böck, W. Utschick, "Decoupling networks and super-quadratic gains for RIS systems with mutual coupling," arXiv:2411.17779, 2024.
BD-RIS with Discrete-Value Scattering Matrix
M. Nerini, S. Shen, and B. Clerckx, "Discrete-value group and fully connected architectures for beyond diagonal reconfigurable intelligent surfaces," IEEE Trans. Veh. Technol., 2023.
Applications of BD-RIS and Integration with Other Technologies
Applications of BD-RIS
H. Wang, Z. Han, and L. Swindlehurst, "Channel reciprocity attacks using intelligent surfaces with non-diagonal phase shifts," IEEE Open J. Commun. Soc., 2024.
Y. Zhao, H. Li, M. Franceschetti, and B. Clerckx, "Channel shaping using beyond diagonal reconfigurable intelligent surface: Analysis, optimization, and enhanced flexibility," arXiv:2407.15196, 2024.
H. Yahya, H. Li, M. Nerini, B. Clerckx, and M. Debbah, "Beyond diagonal RIS: Passive maximum ratio transmission and interference nulling enabler," arXiv:2408.09887, 2024.
H. Wang, J. Nossek and A. L. Swindlehurst, "Beyond-diagonal RIS attacks on physical layer key generation," IEEE International Workshop on Signal Processing Advances in Wireless Communications (SPAWC), 2024.
BD-RIS and Sensing/Localization
Y. Zhang, X. Shao, H. Li, B. Clerckx, and R. Zhang, "Full-space wireless sensing enabled by multi-sector Intelligent surfaces," arXiv:2406.15945, 2024.
M. Raeisi, H. Chen, H. Wymeersch, and E. Basar, "Efficient localization with base station-integrated beyond diagonal RIS," arXiv:2411.13295, 2024.
BD-RIS and Terahertz (THz)
A. Mahmood, T. X. Vu, S. Chatzinotas, and B. Ottersten, "Enhancing indoor and outdoor THz communications with beyond diagonal-IRS: Optimization and performance analysis," arXiv:2403.17913, 2024.
W. U. Khan, C. K. Sheemar, Z. Abdullah, E. Lagunas, and S. Chatzinotas, "Beyond diagonal IRS assisted ultra massive THz systems: A low resolution approach," arXiv:2406.15880, 2024.
BD-RIS and Non-Terrestrial Networks (NTNs)
W. U. Khan, A. Mahmood, M. A. Jamshed, E. Lagunas, M. Ahmed, and S. Chatzinotas, "Beyond diagonal RIS for 6G non-terrestrial networks: Potentials and challenges," IEEE Network, 2024.
BD-RIS and Stacked Intelligent Metasurface (SIM)
M. Nerini, and B. Clerckx, "Physically consistent modeling of stacked intelligent metasurfaces implemented with beyond diagonal RIS," IEEE Commun. Lett., 2024.
BD-RIS and Simultaneous Wireless Information and Power Transfer (SWIPT)/Wireless Power Transfer (WPT)
T. D. Hua, M. Mohammadi, H. Q. Ngo, and M. Matthaiou, "Cell-free massive MIMO SWIPT with beyond diagonal reconfigurable intelligent surfaces," arXiv:2402.00646, 2024.
A. Azarbahram, O. L. A. López, B. Clerckx, M. Di Renzo, and M. Latva-aho, "Beyond diagonal reconfigurable intelligent surfaces for multi-carrier RF wireless power transfer," arXiv:2501.01787, 2025.
BD-RIS and Physical Layer Security
A. Agarwal, and K. Singh, "Enhanced physical layer security for wireless systems with non-diagonal IRS," IEEE International Conference on Advanced Networks and Telecommunications Systems (ANTS), 2023.
S. Lin, Y. Zou, Y. Jiang, L. Yang, Z. Cui, and L. Tran, "Securing FC-RIS and UAV empowered multiuser communications against a randomly flying eavesdropper," arXiv:2408.14261, 2024.
BD-RIS and Unmanned Aerial Vehicle (UAV)
A. M. Huroon, Y. -C. Huang, and L. -C. Wang, "Optimized transmission strategy for UAV-RIS 2.0 assisted communications using rate splitting multiple access," IEEE Vehicular Technology Conference (VTC2023-Fall), 2023.
A. Mahmood, T. X. Vu, W. U. Khan, S. Chatzinotas, and B. Ottersten, "Joint computation and communication resource optimization for beyond diagonal UAV-IRS empowered MEC networks," arXiv:2311.07199, 2023.
BD-RIS and Massive MIMO
A. Mishra, Y. Mao, C. D’Andrea, S. Buzzi, and B. Clerckx, "Transmitter side beyond-diagonal reconfigurable intelligent surface for massive MIMO networks," IEEE Wireless Commun. Lett., 2023.
BD-RIS and Dual-Function Radar-Communication (DFRC)/Integrated Sensing and Communication (ISAC)
B. Wang, H. Li, Z. Cheng, S. Shen, and B. Clerckx, "A dual-function radar-communication system empowered by beyond diagonal reconfigurable intelligent surface," IEEE Trans. Commun., 2024.
T. Esmaeilbeig, K. V. Mishra, and M. Soltanalian, "Beyond diagonal RIS: Key to next-generation integrated sensing and communications?," arXiv:2402.14157, 2024.
Z. Guang, Y. Liu, Q. Wu, W. Wang, and Q. Shi, "Power minimization for ISAC system using beyond diagonal reconfigurable intelligent surface," IEEE Trans. Veh. Technol., 2024.
Z. Liu, Y. Liu, S. Shen, Q. Wu, and Q. Shi, "Enhancing ISAC network throughput using beyond diagonal RIS," IEEE Wireless Commun. Lett., 2024.
K. Chen, and Y. Mao, "Transmitter side beyond-diagonal RIS for mmWave integrated sensing and communications," IEEE International Workshop on Signal Processing Advances in Wireless Communications (SPAWC), 2024.
BD-RIS and Rate-Splitting Multiple Access (RSMA)
T. Fang, Y. Mao, S. Shen, Z. Zhu, and B. Clerckx, "Fully connected reconfigurable intelligent surface aided rate-splitting multiple access for multi-user multi-antenna transmission," IEEE International Conference on Communications Workshops (ICC Workshops), 2022.
M.-A. Kim, S.-G. Yoo, H.-D. Kim, K.-H. Shin, Y.-H. You, and H.-K. Song, "Group-connected impedance network of RIS-assisted rate-splitting multiple access in MU-MIMO wireless communication systems," Sensors, 2023.
M. Soleymani, I. Santamaria, E. Jorswieck, and B. Clerckx, "Optimization of rate-splitting multiple access in beyond diagonal RIS-assisted URLLC systems," IEEE Trans. Wireless Commun., 2023.
H. Li, S. Shen, and B. Clerckx, "Synergizing beyond diagonal reconfigurable intelligent surface and rate-splitting multiple access," IEEE Trans. Wireless Commun., 2024.
S. Khisa, A. Amhaz, M. Elhattab, C. Assi, and S. Sharafeddine, "Gradient-based meta learning for uplink RSMA with beyond diagonal RIS," arXiv:2410.17896, 2024.
BD-RIS and Non-Orthogonal Multiple Access (NOMA)
Q. Zhang, G. Luo, Z. Dong, F. Sun, X. Wang, and J. Liu, "Beyond-diagonal reconfigurable intelligent surface enhanced NOMA systems," IEEE Wireless Commun. Lett., 2024.