References & Further Reading

References

3GPP, 3GPP TR 38.901: Study on Channel Model for Frequencies from 0.5 to 100 GHz (Release 17), 2022. [Link]
The baseline channel model for all 3GPP 5G NR performance evaluations. Section 7.5 codifies the WSS-US assumption that Section 27.1 puts into question. Rel-18 adds near-field support; Rel-20+ is expected to address XL-MIMO non-stationarity but had not as of the time of writing.
E. de Carvalho, A. Ali, A. Amiri, M. Angjelichinoski, R. W. Heath, Non-Stationarities in Extra-Large-Scale Massive MIMO, 2020
The canonical survey on XL-MIMO non-stationarity. Introduces the visibility-region terminology and presents measurement evidence from multiple campaigns. Defines the open problem that Section 27.1 revisits.
A. Amiri, M. Angjelichinoski, E. de Carvalho, R. W. Heath, Extremely Large Aperture Massive MIMO: Low Complexity Receiver Architectures, 2022
Derives the rate-loss bound under mismatched WSS and proposes low-complexity VR-aware receivers. The theoretical basis for Theorem 27.1.1.
E. Bjornson, L. Sanguinetti, Spatial Correlation Matters: A Non-Stationary Analysis of Massive MIMO, 2019
Early paper in the non-stationary modeling thread, focused on deriving closed-form capacity expressions that do not assume WSS. Referenced throughout Section 27.1.
P. A. Bello, Characterization of Randomly Time-Variant Linear Channels, 1963
The origin of the WSS-US channel model. Bello introduced the 2x2 taxonomy of time/scatterer stationarity and explicitly warned that WSS-US is a modeling choice, not a physical law. Cited in the historical note of Section 27.1.
E. Bjornson, L. Sanguinetti, Scalable Cell-Free Massive MIMO Systems, 2020
Introduces the scalability taxonomy and the distributed/centralized processing tradeoff for cell-free systems. Theorem 27.2.1 is a consolidated version of results from this paper plus Interdonato et al. 2019.
G. Interdonato, E. Bjornson, H. Q. Ngo, P. Frenger, E. G. Larsson, Ubiquitous Cell-Free Massive MIMO Communications, 2019
Comprehensive survey of cell-free massive MIMO covering architecture, fronthaul, and scalable processing. Referenced in Section 27.2 for the history of how CoMP evolved into cell-free.
S. Buzzi, C. D'Andrea, Cell-Free Massive MIMO: User-Centric Approach, 2017
Introduces user-centric clustering as a middle ground between fully centralized and fully distributed cell-free processing. Referenced in the proof sketch of Theorem 27.2.1.
H. Q. Ngo, A. Ashikhmin, H. Yang, E. G. Larsson, T. L. Marzetta, Cell-Free Massive MIMO Versus Small Cells, 2017
The foundational paper on cell-free massive MIMO. Establishes the baseline performance and fronthaul analysis that Section 27.2 builds upon.
A. Sabharwal, P. Schniter, D. Guo, D. W. Bliss, S. Rangarajan, R. Wichman, In-Band Full-Duplex Wireless: Challenges and Opportunities, 2014
The definitive survey of full-duplex wireless prior to massive MIMO integration. Describes the three-stage cancellation cascade codified in Definition 27.3.2.
D. Bharadia, E. McMilin, S. Katti, Full Duplex Radios, 2013
The first practical full-duplex demonstration with $>$110 dB total cancellation in a compact COTS radio. The reference implementation for Section 27.3.
E. Dinc, H. Arslan, A Survey of Self-Interference Management Techniques for Single-Frequency Full-Duplex Wireless Communications, 2017
Covers the intersection of full-duplex and massive MIMO, including the spatial-nulling approach of Theorem 27.3.2. A useful entry point to the pre-2020 literature on FD massive MIMO.
E. Everett, C. Shepard, L. Zhong, A. Sabharwal, SoftNull: Many-Antenna Full-Duplex Wireless via Digital Beamforming, 2016
Experimental validation of spatial nulling for FD massive MIMO on the Rice WARP testbed. Demonstrates the $\sim 20$ dB spatial cancellation gain at 64-element scale.
B. Smida, A. Sabharwal, G. Fodor, G. C. Alexandropoulos, H. A. Suraweera, C.-B. Chae, Full-Duplex Wireless for 6G: Progress Brings New Opportunities and Challenges, 2023
The most recent comprehensive survey of FD wireless. Lists the commercial deployment barriers synthesized in the engineering note of Section 27.3.
A. Pizzo, T. L. Marzetta, L. Sanguinetti, Spatially-Stationary Model for Holographic MIMO Small-Scale Fading, 2020
The foundational paper that established the $(L/L_F)^4$ DoF scaling for holographic MIMO surfaces. Cited throughout Section 27.4 as the theoretical anchor; the Landau-Slepian-Pollak machinery is pulled into MIMO theory for the first time.
C. Huang, S. Hu, G. C. Alexandropoulos, A. Zappone, C. Yuen, R. Zhang, M. Di Renzo, M. Debbah, Holographic MIMO Surfaces for 6G Wireless Networks: Opportunities, Challenges, and Trends, 2020
A tutorial survey of holographic MIMO from an architectural perspective. Complements Pizzo et al. 2020 with practical manufacturing considerations. Referenced in the engineering note of Section 27.4.
S. Gong, C. Xing, P. Yue, L. Zhao, T. Q. S. Quek, Hardware-Impaired Holographic MIMO: From Theory to Practice, 2023
Quantifies the gap between theoretical and manufacturable holographic surfaces. Cited in Section 27.4 for the manufacturing-constraint discussion.
E. Basar, M. Di Renzo, J. de Rosny, M. Debbah, M.-S. Alouini, R. Zhang, Wireless Communications Through Reconfigurable Intelligent Surfaces, 2019
Introduces the RIS signal model used throughout Section 27.5 and derives the cascaded channel form.
M. Di Renzo, A. Zappone, M. Debbah, M.-S. Alouini, C. Yuen, J. de Rosny, S. Tretyakov, Smart Radio Environments Empowered by Reconfigurable Intelligent Surfaces: How It Works, State of Research, and The Road Ahead, 2020
The definitive early survey of RIS. Lays out the research roadmap that Section 27.5 partially inherits and updates for the cell-free convergence angle.
E. Bjornson, H. Wymeersch, B. Matthiesen, P. Popovski, L. Sanguinetti, E. de Carvalho, Reconfigurable Intelligent Surfaces: A Signal Processing Perspective With Wireless Applications, 2022
A signal-processing-centric RIS survey that clarifies the economic and architectural tradeoffs between active APs and passive RIS. The framing of RIS as a passive AP in Section 27.5 follows this paper.
O. Ozdogan, E. Bjornson, E. G. Larsson, Intelligent Reflecting Surfaces: Physics, Propagation, and Pathloss Modeling, 2020
Derives the $1/(d_1^2 d_2^2)$ cascaded pathloss scaling cited in Theorem 27.5.1 and quantifies the $N_{\text{RIS}}^2$ coherent combining gain.
C. Huang, S. Hu, et al., Integrating Reconfigurable Intelligent Surfaces with Cell-Free Massive MIMO: A Review and Open Problems, 2021
Survey of joint RIS and cell-free architecture proposals. Foundation for Section 27.5's convergence discussion.
Q. Wu, R. Zhang, Intelligent Reflecting Surface Enhanced Wireless Network via Joint Active and Passive Beamforming, 2019
Foundational paper on joint active AP and RIS phase profile optimization. Used in the engineering note of Section 27.5 to estimate SDP problem size.
Q. Wu, R. Zhang, Towards Smart and Reconfigurable Environment: Intelligent Reflecting Surface Aided Wireless Network, 2019
Alternating-optimization approach to joint RIS and active beamforming. Complements the SDP approach of Wu-Zhang 2019 TWC.
G. Caire, CommIT (TU Berlin), Huawei 6G Research, 6G Wireless Technologies: Advancing MIMO and AI Integration (Workshop Report), 2023. [Link]
The 2023 CommIT/Huawei 6G workshop synthesis. Immediate inspiration for the research agenda of Section 27.6 and the industry-engineering gaps discussion. CommIT contribution.
ITU-R, Report ITU-R M.2516-0: Future Technology Trends of Terrestrial IMT Systems towards 2030 and Beyond, 2023. [Link]
The ITU-R framing document for IMT-2030 (6G). Identifies the research priorities that the chapter's research-agenda section aligns with.
C. E. Shannon, Communication in the Presence of Noise, 1949
Shannon's second foundational paper, which closed with the warning that information-theoretic limits require engineering that the theory does not prescribe. Quoted in the historical note of Section 27.6 as the framing for why the research agenda is not closed.