References & Further Reading
References
- Q. Wu and R. Zhang, Intelligent Reflecting Surface Enhanced Wireless Network via Joint Active and Passive Beamforming, 2019
The signal model and AO framework reused throughout. Section II.B extends to multi-user.
- C. Pan et al., Multicell MIMO Communications Relying on Intelligent Reflecting Surfaces, 2020
The definitive MU-MISO-RIS paper. Problem (P1) is the sum-rate formulation used throughout Section 7.2.
- C. Huang, A. Zappone, M. Debbah, and C. Yuen, Achievable Rate Maximization by Passive Intelligent Mirrors, 2018
Early max-min formulation for RIS. Introduces the bisection + SOCP approach adopted in Section 7.3.
- Q. Shi, M. Razaviyayn, Z.-Q. Luo, and C. He, An iteratively weighted MMSE approach to distributed sum-utility maximization, 2011
The WMMSE framework used inside every AO active update for sum-rate.
- M. Bengtsson and B. Ottersten, Optimal and suboptimal transmit beamforming, 2001
The classical reference for SOCP-based multi-user QoS beamforming. Section 7.3's bisection + SOCP structure is adapted from here.
- G. Caire and I. Atzeni, Multiuser RIS Scheduling with Limited Pilot Budget, 2022
CommIT contribution. Hierarchical multi-user RIS scheduling that clusters users and amortizes pilot overhead. Key practical enabler for MU-RIS at scale.
- T. Lan, D. Kao, M. Chiang, and A. Sabharwal, An axiomatic theory of fairness in network resource allocation, 2010
Provides the philosophical framework for sum-rate vs. max-min vs. proportional-fair choices. Relevant context for the tradeoff discussion in Section 7.4.
- G. Zhou, C. Pan, H. Ren, K. Wang, and A. Nallanathan, A Framework of Robust Transmission Design for IRS-Aided MISO Communications With Imperfect Cascaded Channels, 2020
Extends sum-rate/max-min to imperfect CSI using worst-case error minimization. Essential for deployment.
- Q.-U.-A. Nadeem, A. Kammoun, A. Chaaban, M. Debbah, and M.-S. Alouini, Asymptotic Max-Min SINR Analysis of Reconfigurable Intelligent Surface Assisted MISO Systems, 2020
Random-matrix-theory asymptotic analysis of max-min RIS. Beautiful closed-form scaling laws for large $N, K$.
- E. Björnson, Ö. Özdogan, and E. G. Larsson, Reconfigurable intelligent surfaces: Three myths and two critical questions, 2020
Critically examines RIS claims including multi-user capacity. The 'DoF vs SNR' distinction of Section 7.4 is clearly articulated here.
- M. Di Renzo et al., Smart Radio Environments Empowered by Reconfigurable Intelligent Surfaces, 2020
Survey with multi-user system-level perspective. Section V covers capacity and DoF issues.
- H. Guo, Y.-C. Liang, J. Chen, and E. G. Larsson, Weighted Sum-Rate Maximization for Reconfigurable Intelligent Surface Aided Wireless Networks, 2020
Multi-user WMMSE-RIS; Algorithm 1 is the canonical reference AO implementation.
Further Reading
Resources for deeper study of multi-user RIS optimization.
RIS-aided MU-MIMO with imperfect CSI
Zhou et al. (2020), 'Robust Transmission Design...' (ch07 reference)
The real-world extension of Section 7.2 including CSI uncertainty via worst-case and stochastic frameworks.
Asymptotic analysis (RMT) of MU-RIS
Nadeem et al. (2020), 'Asymptotic Max-Min SINR Analysis' (ch07 reference)
Closed-form performance bounds for large $N, K$ regimes; useful for back-of-envelope deployment sizing.
Hierarchical multi-user RIS scheduling
Caire and Atzeni (2022), 'Multiuser RIS Scheduling...' (CommIT contribution)
Practical scheduling algorithm for MU-RIS at scale. The foundation of efficient multi-user deployments.
RIS for NOMA
Mu, Liu, Guan, Yuen, Alouini (2020), 'Capacity and Optimal Resource Allocation for IRS-Assisted Multi-User Communication Systems,' IEEE TCOM
Non-orthogonal multiple access variant of MU-RIS. Same framework, different power-domain user multiplexing.
Three myths of RIS
Björnson, Özdogan, Larsson (2020), 'Three myths and two critical questions' (ch07 reference)
A healthy skeptical read. Clarifies the DoF vs. SNR distinction and debunks inflated RIS claims.