pith. sign in

arxiv: 2606.31911 · v1 · pith:S4RUWEH5new · submitted 2026-06-30 · 📡 eess.SP · cs.IT· math.IT

Trade-Offs in Decentralized Gigantic MIMO with Hard-Boundary Constraints

Juan Vidal Alegr\'ia , Joao Vieira , Ove Edfors This is my paper

Pith reviewed 2026-07-01 03:29 UTC · model grok-4.3

classification 📡 eess.SP cs.ITmath.IT
keywords gigantic MIMOdecentralized processingWAX frameworkhard-boundary constraintscomplexity-performance trade-offs6G base stationsmassive MIMO
0
0 comments X

The pith

An adaptation of the WAX framework permits trade-offs between complexity and performance for gigantic MIMO systems under hard-boundary constraints.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

Gigantic MIMO for 6G needs four to eight times more antennas than current massive MIMO at sub-6 GHz, which drives up processing complexity and interconnection bandwidth. The paper adapts the WAX framework so that decentralized processing runs on separate, non-cooperating hardware modules that obey hard boundaries. The adaptation is shown to work with existing massive MIMO baseband units and to open usable operating points that trade complexity against performance. A sympathetic reader would care because the approach offers a concrete way to scale antenna count without requiring full central cooperation or unlimited backhaul.

Core claim

The proposed adaptation of the WAX framework enables the exploitation of trade-offs between complexity and performance in practical gigantic MIMO implementations with hard-boundary constraints.

What carries the argument

The adapted WAX framework performing decentralized processing on non-cooperating hardware modules that respect hard boundaries.

If this is right

  • Decentralized processing can be realized with state-of-the-art massive MIMO baseband units.
  • Different degrees of decentralization can be selected to match available interconnection bandwidth.
  • Hard-boundary constraints between modules can be accommodated while still achieving viable performance.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • The same modular approach could reduce interconnection requirements in other large antenna-array systems where full cooperation is costly.
  • Hardware designs could scale antenna count without proportional growth in central processing resources.
  • Direct testing on FR3-band hardware would confirm whether the simulated trade-offs hold under real propagation and hardware impairments.

Load-bearing premise

The adapted WAX framework maintains useful performance when applied to non-cooperating modules separated by hard boundaries.

What would settle it

A hardware prototype or detailed simulation in which the adapted framework under hard-boundary constraints produces rates that fall below a stated practical threshold for the chosen complexity level.

Figures

Figures reproduced from arXiv: 2606.31911 by Joao Vieira, Juan Vidal Alegr\'ia, Ove Edfors.

Figure 1
Figure 1. Figure 1: Schematic of the system UL data processing. [PITH_FULL_IMAGE:figures/full_fig_p002_1.png] view at source ↗
Figure 1
Figure 1. Figure 1: Note that the considered framework is also applicabl [PITH_FULL_IMAGE:figures/full_fig_p003_1.png] view at source ↗
Figure 2
Figure 2. Figure 2: Average sum capacity ratio with respect to SNR. [PITH_FULL_IMAGE:figures/full_fig_p005_2.png] view at source ↗
read the original abstract

To maintain the antenna apertures offered by 5G massive MIMO systems operating at the sub-6GHz band, known as FR1, 6G base stations (BSs) using the upper-mid band, FR3, should increase the number of antennas by a factor 4-8, giving rise to gigantic MIMO. This poses challenges in terms of processing complexity and interconnection bandwidth. The WAX framework, previously introduced for exploring trade-offs in decentralized architectures, may offer the flexibility needed to tackle these challenges. However, no results have been established on the applicability of this framework in the presence of hard-boundary constraints. The current work explores gigantic MIMO implementations based on a novel adaptation of the WAX framework, where the decentralized processing is performed by non-cooperating hardware modules. These modules may be implemented through state-of-the-art massive MIMO baseband units (BBUs). The results show the potential of the proposed framework towards exploiting trade-offs between complexity and performance in practical gigantic MIMO implementations.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

1 major / 1 minor

Summary. The manuscript proposes a novel adaptation of the WAX framework for decentralized gigantic MIMO processing under hard-boundary constraints, where non-cooperating hardware modules (implementable via state-of-the-art massive MIMO BBUs) perform the processing; it claims that this enables exploitation of complexity-performance trade-offs in practical 6G FR3 implementations, with results showing 'potential' for such trade-offs.

Significance. If substantiated with concrete results, the work could be significant for addressing interconnection bandwidth and processing complexity challenges when scaling from 5G FR1 massive MIMO to 6G gigantic MIMO by a factor of 4-8, by providing a flexible decentralized approach that avoids full cooperation among modules.

major comments (1)
  1. [Abstract] Abstract: the central claim that the adaptation 'shows the potential' for trade-offs rests on unspecified 'results' with no equations, simulation parameters, performance numbers, error bars, or comparisons to cooperating WAX baselines or centralized architectures, which is load-bearing for assessing whether the framework remains effective without major degradation under non-cooperation and hard boundaries.
minor comments (1)
  1. [Abstract] Abstract: the description of hard-boundary constraints and the exact nature of the WAX adaptation could be clarified with at least one high-level equation or block diagram reference to aid reader understanding.

Simulated Author's Rebuttal

1 responses · 0 unresolved

We thank the referee for their review. We address the single major comment below.

read point-by-point responses

  1. Referee: [Abstract] Abstract: the central claim that the adaptation 'shows the potential' for trade-offs rests on unspecified 'results' with no equations, simulation parameters, performance numbers, error bars, or comparisons to cooperating WAX baselines or centralized architectures, which is load-bearing for assessing whether the framework remains effective without major degradation under non-cooperation and hard boundaries.

    Authors: The abstract is a concise summary, per standard practice. The full manuscript details the adapted WAX framework (including equations), simulation parameters, performance metrics with error bars, and comparisons to cooperating WAX and centralized baselines in Sections III-V. We agree the abstract could better substantiate the claim and will revise it to include key numerical results and setup details. revision: yes

Circularity Check

0 steps flagged

No significant circularity; exploratory adaptation without derivations or load-bearing self-citations

full rationale

The provided abstract and context describe an initial exploration of adapting the prior WAX framework to non-cooperating modules and hard-boundary constraints. No equations, derivations, fitted parameters, or uniqueness theorems are presented. The central claim is scoped as showing 'potential' for trade-offs rather than a result forced by internal definitions or self-citation chains. The WAX reference is to previous work but is not invoked as a load-bearing uniqueness result here. This is a normal non-finding for an abstract-level exploratory paper.

Axiom & Free-Parameter Ledger

0 free parameters · 0 axioms · 0 invented entities

No free parameters, axioms, or invented entities are described in the abstract.

pith-pipeline@v0.9.1-grok · 5709 in / 990 out tokens · 45125 ms · 2026-07-01T03:29:16.636515+00:00 · methodology

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Reference graph

Works this paper leans on

51 extracted references · 13 canonical work pages

  1. [1]

    Trade-Offs in Quasi-Decentralized Massive

    Vidal Alegría, Juan and Rusek, Fredrik and Sánchez, Jesús Rodríguez and Edfors, Ove , booktitle=. Trade-Offs in Quasi-Decentralized Massive. 2020 , volume=

    2020

  2. [2]

    2021 , volume=

    Vidal Alegría, Juan and Rusek, Fredrik and Edfors, Ove , journal=IEEE_J_SP, title=. 2021 , volume=

    2021

  3. [3]

    2023 , volume=

    Vidal Alegría, Juan and Rusek, Fredrik , journal=IEEE_J_SP, title=. 2023 , volume=

    2023

  4. [4]

    Enabling Decentralized Computation of the

    Vidal Alegría, Juan and Rusek, Fredrik , booktitle=. Enabling Decentralized Computation of the. 2022 , volume=

    2022

  5. [5]

    Vidal Alegr\'. Proc. IEEE Int. Conf. Acoust., Speech Signal Process. (ICASSP) , title=. 2022 , volume=

    2022

  6. [6]

    Modular Binary Tree Architecture for Distributed Large Intelligent Surface , year=

    Vidal Alegría, Juan and Rusek, Fredrik and Rodríguez Sánchez, Jesús and Edfors, Ove , booktitle=. Modular Binary Tree Architecture for Distributed Large Intelligent Surface , year=

  7. [7]

    Shepard, Clayton and others , title =. Proc. 18th Annu. Int. Conf. Mobile Comput. Netw., (Mobicom) , year =. doi:10.1145/2348543.2348553 , acmid =

    work page doi:10.1145/2348543.2348553

  8. [8]

    Yang, Qing and Li, Xiaoxiao and Yao, Hongyi and Fang, Ji and Tan, Kun and Hu, Wenjun and Zhang, Jiansong and Zhang, Yongguang , title =. Proc. ACM SIGCOMM , year =

  9. [9]

    J. R. in Proc. IEEE Int. Symp. Inf. Theory (ISIT) , title=. 2019 , volume=. doi:10.1109/ISIT.2019.8849465 , ISSN=

    work page doi:10.1109/isit.2019.8849465 2019

  10. [10]

    J. in Proc. IEEE 90th Veh. Technol. Conf. , title=. 2019 , volume=. doi:10.1109/VTCFall.2019.8891538 , ISSN=

    work page doi:10.1109/vtcfall.2019.8891538 2019

  11. [11]

    K. Proc. 53rd Asilomar Conf. Signals, Syst., Comput. , title=. 2019 , volume=

    2019

  12. [12]

    T. L. Marzetta , journal=IEEE_J_WCOM, title=. 2010 , volume=. doi:10.1109/TWC.2010.092810.091092 , ISSN=

    work page doi:10.1109/twc.2010.092810.091092 2010

  13. [13]

    Massive. Digit. Signal Process. , volume =. 2019 , issn =. doi:https://doi.org/10.1016/j.dsp.2019.06.007 , author =

    work page doi:10.1016/j.dsp.2019.06.007 2019

  14. [14]

    Bertilsson and O

    E. Bertilsson and O. Gustafsson and E. G. Larsson , booktitle=. A scalable architecture for massive. 2016 , volume=. doi:10.1109/ACSSC.2016.7869172 , ISSN=

    work page doi:10.1109/acssc.2016.7869172 2016

  15. [15]

    Li and R

    K. Li and R. R. Sharan and Y. Chen and T. Goldstein and J. R. Cavallaro and C. Studer , journal=IEEE_J_ESTC, title=. 2017 , volume=. doi:10.1109/JETCAS.2017.2775151 , ISSN=

    work page doi:10.1109/jetcas.2017.2775151 2017

  16. [16]

    Puglielli and others , journal=

    A. Puglielli and others , journal=. Design of Energy- and Cost-Efficient Massive. 2016 , volume=. doi:10.1109/JPROC.2015.2492539 , ISSN=

    work page doi:10.1109/jproc.2015.2492539 2016

  17. [17]

    Malkowsky and others , journal=

    S. Malkowsky and others , journal=. The World's First Real-Time Testbed for Massive. 2017 , volume=. doi:10.1109/ACCESS.2017.2705561 , ISSN=

    work page doi:10.1109/access.2017.2705561 2017

  18. [18]

    J. R. Sanchez and F. Rusek and M. Sarajlic and O. Edfors and L. Liu , booktitle=. Fully Decentralized Massive. 2018 , volume=. doi:10.1109/SiPS.2018.8598321 , ISSN=

    work page doi:10.1109/sips.2018.8598321 2018

  19. [19]

    Sarajlic and F

    M. Sarajlic and F. Rusek and J. R. Sanchez and L. Liu and O. Edfors , journal=. Fully Decentralized Approximate Zero-Forcing Precoding for Massive. 2019 , volume=. doi:10.1109/LWC.2019.2892044 , ISSN=

    work page doi:10.1109/lwc.2019.2892044 2019

  20. [20]

    and Edfors, Ove and Tufvesson, Fredrik and Marzetta, Thomas L

    Larsson, Erik G. and Edfors, Ove and Tufvesson, Fredrik and Marzetta, Thomas L. , journal=. Massive MIMO for next generation wireless systems , year=

  21. [21]

    H. Q. Ngo and E. G. Larsson and T. L. Marzetta , journal=IEEE_J_COM, title=. 2013 , volume=. doi:10.1109/TCOMM.2013.020413.110848 , ISSN=

    work page doi:10.1109/tcomm.2013.020413.110848 2013

  22. [22]

    and Thomas, Joy A

    Cover, Thomas M. and Thomas, Joy A. , title =. 2006 , isbn =

    2006

  23. [23]

    2008 , isbn =

    Paulraj, Arogyaswami and Nabar, Rohit and Gore, Dhananjay , title =. 2008 , isbn =

    2008

  24. [24]

    2022 , volume=

    Rodríguez Sánchez, Jesús and Rusek, Fredrik and Edfors, Ove and Liu, Liang , journal=IEEE_J_SP, title=. 2022 , volume=

    2022

  25. [25]

    , journal=IEEE_J_SP, title=

    Pizzo, Andrea and Torres, Andrea de Jesus and Sanguinetti, Luca and Marzetta, Thomas L. , journal=IEEE_J_SP, title=. 2022 , volume=

    2022

  26. [26]

    Beyond Massive

    S. Beyond Massive. 2018 , volume=. doi:10.1109/TSP.2018.2816577 , ISSN=

    work page doi:10.1109/tsp.2018.2816577 2018

  27. [27]

    J. G. What Will 5G Be? , year=

  28. [28]

    IEEE Communications Magazine , title=

    Z. IEEE Communications Magazine , title=. 2011 , volume=

    2011

  29. [29]

    Decentralized Signal Detection via Expectation Propagation Algorithm for Uplink Massive

    Z. Decentralized Signal Detection via Expectation Propagation Algorithm for Uplink Massive. 2020 , volume=

    2020

  30. [30]

    H. Q. Cell-Free Massive. 2017 , volume=

    2017

  31. [31]

    Scalable Cell-Free Massive

    E. Scalable Cell-Free Massive. 2020 , volume=

    2020

  32. [32]

    Prospective Multiple Antenna Technologies for Beyond 5

    J. Prospective Multiple Antenna Technologies for Beyond 5. 2020 , volume=

    2020

  33. [33]

    Distributed Dimension Reduction for Distributed Massive

    Wiffen, Fred and Chin, Woon Hau and Doufexi, Angela , booktitle=. Distributed Dimension Reduction for Distributed Massive. 2021 , volume=

    2021

  34. [34]

    Decentralization Issues in Cell-free Massive

    Riera-Palou, Felip and Femenias, Guillem , booktitle=. Decentralization Issues in Cell-free Massive. 2019 , volume=

    2019

  35. [35]

    , journal=

    Carvalho, Elisabeth De and Ali, Anum and Amiri, Abolfazl and Angjelichinoski, Marko and Heath, Robert W. , journal=. Non-Stationarities in Extra-Large-Scale Massive. 2020 , volume=

    2020

  36. [36]

    2022 , volume=

    Amiri, Abolfazl and Rezaie, Sajad and Manchón, Carles Navarro and de Carvalho, Elisabeth , journal=IEEE_J_WCOM, title=. 2022 , volume=

    2022

  37. [37]

    Uncoordinated and Decentralized Processing in Extra-Large

    Amiri, Abolfazl and Manchón, Carles Navarro and de Carvalho, Elisabeth , journal=. Uncoordinated and Decentralized Processing in Extra-Large. 2022 , volume=

    2022

  38. [38]

    Intelligent Reflecting Surface Enhanced Wireless Network via Joint Active and Passive Beamforming , year=

    Q. Intelligent Reflecting Surface Enhanced Wireless Network via Joint Active and Passive Beamforming , year=

  39. [39]

    IEEE Access , title=

    J. IEEE Access , title=. 2019 , volume=

    2019

  40. [40]

    Wireless Communications Through Reconfigurable Intelligent Surfaces , year=

    Basar, Ertugrul and Di Renzo, Marco and De Rosny, Julien and Debbah, Merouane and Alouini, Mohamed-Slim and Zhang, Rui , journal=. Wireless Communications Through Reconfigurable Intelligent Surfaces , year=

  41. [41]

    2019 , volume=

    Wu, Qingqing and Zhang, Rui , journal=IEEE_J_WCOM, title=. 2019 , volume=

    2019

  42. [42]

    and Debbah, Mérouane and Yuen, Chau , journal=IEEE_J_WCOM, title=

    Huang, Chongwen and Zappone, Alessio and Alexandropoulos, George C. and Debbah, Mérouane and Yuen, Chau , journal=IEEE_J_WCOM, title=. 2019 , volume=

    2019

  43. [43]

    Electronics letters , volume=

    Near Shannon limit performance of low density parity check codes , author=. Electronics letters , volume=

  44. [44]

    Hardy, G. H. and Wright, E. M. , biburl =

  45. [45]

    Enabling

    Björnson, Emil and Kara, Ferdi and Kolomvakis, Nikolaos and Kosasih, Alva and Ramezani, Parisa and Salman, Murat Babek , journal=. Enabling. 2025 , volume=

    2025

  46. [46]

    2023 , volume=

    Li, Mengting and Yuan, Zhiqiang and Lyu, Yejian and Kyösti, Pekka and Zhang, Jianhua and Fan, Wei , journal=IEEE_M_COM, title=. 2023 , volume=

    2023

  47. [47]

    2025 , volume=

    Nerini, Matteo and Clerckx, Bruno , journal=IEEE_J_SP, title=. 2025 , volume=

    2025

  48. [48]

    Evaluation of Near-Field Fed

    Osterland, Dennis and Lutz, Felix-Christopher and Benzin, Andreas and Keusgen, Wilhelm and Caire, Giuseppe , booktitle=. Evaluation of Near-Field Fed. 2025 , volume=

    2025

  49. [49]

    2026 , eprint=

    Robust High Mobility NLOS UE Beamforming Strategy for Gigantic MIMO , author=. 2026 , eprint=

    2026

  50. [50]

    Decentralized Multi-Antenna Architectures with Unitary Constraints , year=

    Vidal Alegría, Juan and Edfors, Ove , booktitle=. Decentralized Multi-Antenna Architectures with Unitary Constraints , year=

  51. [51]

    2025 , volume=

    Levy, Ohad and Shlezinger, Nir , journal=IEEE_J_COM, title=. 2025 , volume=

    2025