References & Further Reading

References

Q. Wu and R. Zhang, Intelligent Reflecting Surface Enhanced Wireless Network via Joint Active and Passive Beamforming, 2019
The single most cited RIS paper. Establishes the system model, derives $N^2$ SNR scaling, and introduces the alternating-optimization framework for joint active-passive beamforming. Essential reading.
E. Basar, M. Di Renzo, J. de Rosny, M. Debbah, M.-S. Alouini, and R. Zhang, Wireless Communications Through Reconfigurable Intelligent Surfaces, 2019
The survey that gave the field its name and vocabulary. Comprehensive coverage of hardware options, system models, and early results. A good first read before diving into specific algorithms.
M. Di Renzo, A. Zappone, M. Debbah, M.-S. Alouini, C. Yuen, J. de Rosny, and S. Tretyakov, Smart Radio Environments Empowered by Reconfigurable Intelligent Surfaces: How It Works, State of Research, and the Road Ahead, 2020
An encyclopedic survey. Pay attention to Sections II–III for hardware, Section V for channel modeling, and Section VII for deployment. Seventy-six pages, but the reference standard.
E. Björnson, Ö. Özdogan, and E. G. Larsson, Intelligent Reflecting Surface Versus Decode-and-Forward: How Large Surfaces Are Needed to Beat Relaying?, 2020
The crossover analysis between RIS and relays. Introduces the 'Björnson threshold' — the minimum $N$ for an RIS to match a DF relay — and pushes back against the 'RIS is always better' narrative.
S. W. Ellingson, Path Loss in Reconfigurable Intelligent Surface-Enabled Channels, 2021
Careful derivation of the path loss for both the 'anomalous mirror' ($1/(d_1+d_2)^2$) and 'point scatterer' ($1/d_1^2 d_2^2$) regimes, and the transition between them. Resolves the early-literature confusion about RIS path loss.
W. Tang, M. Z. Chen, X. Chen, J. Y. Dai, Y. Han, M. Di Renzo, Y. Zeng, S. Jin, Q. Cheng, and T. J. Cui, Wireless Communications With Reconfigurable Intelligent Surface: Path Loss Modeling and Experimental Measurements, 2021
First experimental measurements of RIS path loss with a 2-bit RIS prototype. Validates the theoretical $N^2 A_e^2 / (4\pi)^2 d_1^2 d_2^2$ model and calibrates the constants.
C. Liaskos, S. Nie, A. Tsioliaridou, A. Pitsillides, S. Ioannidis, and I. Akyildiz, A New Wireless Communication Paradigm through Software-Controlled Metasurfaces, 2018
One of the earliest framings of the 'programmable wireless environment' concept. Broader and more speculative than the later technical papers; useful for historical perspective and vision.
C. Pan, H. Ren, K. Wang, J. F. Kolb, M. Elkashlan, M. Chen, M. Di Renzo, Y. Hao, J. Wang, A. L. Swindlehurst, X. You, and L. Hanzo, Reconfigurable Intelligent Surfaces for 6G Systems: Principles, Applications, and Research Directions, 2022
Forward-looking survey with emphasis on 6G use cases. Good companion to Di Renzo et al. (2020) for seeing where the field is headed.
G. Caire et al., Multiuser Multibeam Array-Fed RIS for High-Frequency Bands, 2023
CommIT contribution. Array-fed RIS architecture: a small active array illuminates a large passive RIS. Eigenmode decomposition of the BS–RIS channel governs the number of independent beams. The system-level result motivating the entire Part III of this book (Chapter 11).
D. M. Pozar, Microwave Engineering, Wiley, 4th ed., 2012
Standard graduate text on microwave hardware. Chapters 2 and 3 on reflection coefficients and S-parameters are the right background for the hardware sections of Chapter 2 in this book.
C. A. Balanis, Antenna Theory: Analysis and Design, Wiley, 4th ed., 2016
Authoritative reference on antennas and arrays. Chapter 6 on linear arrays and Chapter 14 on reflector antennas are directly relevant to RIS modeling.