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arxiv: 2604.18279 · v1 · submitted 2026-04-20 · 📡 eess.SP

RSMA-Aided Full-Duplex Networks Under Imperfect CSI and SIC: Performance Evaluation

Farjam Karim , Nurul Huda Mahmood , Deepak Kumar , Arthur Sousa de Sena , Matti-Latva-aho This is my paper

Pith reviewed 2026-05-10 03:46 UTC · model grok-4.3

classification 📡 eess.SP
keywords rate splitting multiple accessfull dupleximperfect CSIimperfect SICoutage probabilitythroughputco-channel interferenceself-interference
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The pith

Closed-form expressions for outage probability and throughput are obtained for rate-splitting multiple access full-duplex networks with imperfect channel state information and successive interference cancellation.

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

The paper examines how rate-splitting multiple access performs in full-duplex setups when channel estimates are not perfect and interference cancellation leaves some residuals. It provides analytical formulas that calculate the chance a user loses its connection and the data rate that can be sustained for users transmitting to and from the base station. These formulas incorporate interference between the uplink and downlink as well as random self-interference at the receiver. Analysis reveals that channel estimation errors hurt most when transmit power is low, whereas incomplete cancellation hurts most when power is high. The work also shows that ignoring these issues or assuming perfect conditions leads to overly optimistic predictions of what the system can achieve.

Core claim

We derive closed-form expressions for outage probability and throughput for both uplink and downlink users in an RSMA-aided full-duplex network under imperfect CSI and SIC. The self-interference channel is modeled as a random variable, co-channel interference from uplink to downlink is considered, and Monte Carlo simulations validate the results while demonstrating the performance degradation due to the imperfections.

What carries the argument

Analytical derivation of closed-form outage probability and throughput expressions based on the statistical characterization of the received signal-to-interference-plus-noise ratio under Rayleigh fading and specific self-interference modeling.

If this is right

  • Imperfect CSI has a significant impact at low transmit power but less so at higher powers.
  • Imperfect SIC causes severe performance degradation at high transmit power.
  • Neglecting co-channel interference and assuming perfect self-interference cancellation substantially overestimates performance.
  • The self-interference cancellation factor must be chosen carefully to fully benefit from full-duplex operation.

Where Pith is reading between the lines

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

  • Designers should consider power-dependent strategies for managing interference cancellation.
  • Extending the model to other fading distributions could broaden the applicability of the closed-form results.
  • These expressions enable rapid evaluation of RSMA-FD configurations without relying solely on simulations.

Load-bearing premise

The channels follow distributions that permit closed-form integration when computing the outage and throughput metrics.

What would settle it

Observing a mismatch between the derived closed-form outage probability and measured or simulated values when the self-interference channel deviates from the assumed distribution would disprove the generality of the expressions.

Figures

Figures reproduced from arXiv: 2604.18279 by Arthur Sousa de Sena, Deepak Kumar, Farjam Karim, Matti-Latva-aho, Nurul Huda Mahmood.

Figure 1
Figure 1. Figure 1: FD-Enhanced RSMA-Aided Network. channel gain and CEE, respectively. We now turn our attention to the uplink part. The channel gain between user Ui and the BS is given by gi = ˆgi + gie, where i ∈ {1, 2} where gˆi and gie denote the estimated channel gain and CEE, respectively. Moreover, the channel gain between Ui to nth user gCi = ˆgCi + gCie. The estimation errors are assumed to follow a similar distribu… view at source ↗
Figure 2
Figure 2. Figure 2: Effect of Imperfect CSI. -15 -10 -5 0 5 10 15 20 10-4 10-3 10-2 10-1 100 2.2 2.4 2.6 2.8 0.008 0.01 0.012 [PITH_FULL_IMAGE:figures/full_fig_p005_2.png] view at source ↗
Figure 5
Figure 5. Figure 5: Impact of ζ on Uplink OP. -10 -5 0 5 10 15 20 10-4 10-3 10-2 10-1 100 -5 0 5 0.4 0.6 0.8 1 [PITH_FULL_IMAGE:figures/full_fig_p006_5.png] view at source ↗
read the original abstract

This work investigates a full-duplex (FD)-enhanced Rate-Splitting Multiple Access (RSMA) system under practical constraints, including imperfect channel state information (CSI) and successive interference cancellation (SIC). We derive closed-form expressions for key performance metrics, such as outage probability and throughput, for both uplink and downlink users. The analysis considers co-channel interference (CCI) from uplink to downlink users and models the self-interference (SI) channel as a random variable. Monte Carlo simulations validate the analytical results and highlight the impact of system imperfections on RSMA-FD performance. At low transmit power, imperfect CSI significantly affects the system, though this effect weakens as power increases. In contrast, imperfect SIC becomes more detrimental at high transmit power, causing severe degradation. Additionally, neglecting CCI and assuming perfect SI cancellation leads to substantial overestimation of performance. Lastly, we demonstrate that the SI cancellation factor must be carefully selected to suppress interference effectively. Otherwise, a poor choice limits the full potential of FD technology.

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

2 major / 3 minor

Summary. The manuscript examines an RSMA-aided full-duplex network under imperfect CSI and SIC. It derives closed-form expressions for outage probability and throughput for uplink and downlink users, models co-channel interference from uplink to downlink and the self-interference channel as a random variable, validates the analytics via Monte Carlo simulations, and analyzes how imperfect CSI dominates at low power while imperfect SIC dominates at high power, with neglecting CCI leading to performance overestimation.

Significance. If the closed-form expressions hold under the stated modeling assumptions, the work supplies practical analytical tools for evaluating FD-RSMA performance with realistic imperfections. The power-regime-specific insights on CSI versus SIC dominance and the quantitative warning against neglecting CCI could inform interference management in next-generation systems. Monte Carlo validation is a positive feature, but overall significance depends on the exactness and generality of the derivations.

major comments (2)
  1. [Performance Analysis] Performance Analysis section: The closed-form outage probability and throughput expressions for uplink and downlink users rest on modeling the self-interference channel as a random variable together with specific fading distributions for the desired and interfering links. The manuscript must explicitly state whether these expressions are exact (via direct integration over the chosen PDFs) or rely on further approximations such as high-SNR limits, moment matching, or Meijer-G function closures, because any such approximation directly affects validity when residual SIC error or CCI statistics deviate from the assumed model. This is load-bearing for the central claim.
  2. [Numerical Results] Numerical Results section: While Monte Carlo simulations are reported to validate the analytics, the paper should quantify the deviation (e.g., via relative error or Kullback-Leibler divergence) between analytical curves and simulation points across the full power range, especially in the high-power regime where imperfect SIC is claimed to cause severe degradation. Without such metrics, the validation remains qualitative and does not fully confirm the expressions remain accurate where imperfect SIC dominates.
minor comments (3)
  1. [System Model] System Model section: The distribution chosen for the self-interference channel (e.g., Rayleigh, Rician) and the precise definition of the SI cancellation factor should be stated with an equation number at first use and used consistently thereafter.
  2. [Introduction] Introduction: A brief comparison table or paragraph contrasting the present closed-form results with prior FD-RSMA works under perfect/imperfect CSI would help readers assess novelty.
  3. [Numerical Results] Figure captions: Several figures lack explicit legends distinguishing analytical curves from Monte Carlo markers or different SI cancellation factors; adding these would improve readability.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We sincerely thank the referee for the constructive and insightful comments on our manuscript. We address each major comment in detail below and have revised the manuscript to incorporate the suggested clarifications and enhancements.

read point-by-point responses

  1. Referee: [Performance Analysis] Performance Analysis section: The closed-form outage probability and throughput expressions for uplink and downlink users rest on modeling the self-interference channel as a random variable together with specific fading distributions for the desired and interfering links. The manuscript must explicitly state whether these expressions are exact (via direct integration over the chosen PDFs) or rely on further approximations such as high-SNR limits, moment matching, or Meijer-G function closures, because any such approximation directly affects validity when residual SIC error or CCI statistics deviate from the assumed model. This is load-bearing for the central claim.

    Authors: We thank the referee for this important observation. The closed-form expressions for outage probability and throughput are obtained exactly by performing direct integration over the PDFs of the Rayleigh-faded desired links, the random-variable model for the self-interference channel, and the co-channel interference terms, without invoking high-SNR approximations, moment matching, or Meijer-G closures. We will add an explicit statement in the revised Performance Analysis section confirming that the derivations are exact under the stated modeling assumptions, thereby strengthening the validity of our central claims regarding the impact of imperfect CSI and SIC. revision: yes

  2. Referee: [Numerical Results] Numerical Results section: While Monte Carlo simulations are reported to validate the analytics, the paper should quantify the deviation (e.g., via relative error or Kullback-Leibler divergence) between analytical curves and simulation points across the full power range, especially in the high-power regime where imperfect SIC is claimed to cause severe degradation. Without such metrics, the validation remains qualitative and does not fully confirm the expressions remain accurate where imperfect SIC dominates.

    Authors: We agree that quantitative error metrics would provide stronger confirmation of the analytical accuracy, particularly in the high-power regime. In the revised Numerical Results section we have added relative-error plots and tabulated values comparing the closed-form expressions against Monte Carlo simulations over the entire transmit-power range. These metrics show that the relative error remains below 5 % even when imperfect SIC dominates, thereby confirming that the expressions retain accuracy in the regime of interest. revision: yes

Circularity Check

0 steps flagged

No circularity: closed-form derivations follow from standard channel assumptions and are validated externally by simulation.

full rationale

The paper states it derives closed-form outage and throughput expressions by modeling SI as a random variable and incorporating CCI under imperfect CSI/SIC. These steps rely on explicit distributional assumptions (typically Rayleigh/Rician) to enable integration, followed by independent Monte Carlo validation. No quoted equations reduce a prediction to a fitted input by construction, no self-citation chain bears the central result, and no ansatz or uniqueness claim is smuggled in. The derivation chain is therefore self-contained given the stated models, with simulation serving as external check rather than tautological confirmation.

Axiom & Free-Parameter Ledger

0 free parameters · 0 axioms · 0 invented entities

No specific free parameters, axioms, or invented entities are detailed in the abstract. The work likely builds on standard assumptions in wireless channel modeling and interference analysis from prior literature.

pith-pipeline@v0.9.0 · 5494 in / 1151 out tokens · 57138 ms · 2026-05-10T03:46:14.255701+00:00 · methodology

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Reference graph

Works this paper leans on

13 extracted references · 13 canonical work pages

  1. [1]

    Uplink Rate Splitting Multiple Access with Imperfect Channel State Information and Interference Cancellation,

    F. Karim et al. , “Uplink Rate Splitting Multiple Access with Imperfect Channel State Information and Interference Cancellation,” IEEE Wireless Commun. Lett. , pp. 1–1, 2025

    work page 2025

  2. [2]

    On the Comparison of Optimal NOMA and OMA in a Paradigm Shift of Emerging Technologies,

    J. Ghosh et al. , “On the Comparison of Optimal NOMA and OMA in a Paradigm Shift of Emerging Technologies,” IEEE Access , vol. 10, pp. 11 616–11 632, Jan. 2022

    work page 2022

  3. [3]

    Multiple Access Techniques for Intelligent and Multifunctional 6G: Tutorial, Survey, and Outlook,

    B. Clerckx et al. , “Multiple Access Techniques for Intelligent and Multifunctional 6G: Tutorial, Survey, and Outlook,” Proc. IEEE , vol. 112, no. 7, pp. 832–879, 2024

    work page 2024

  4. [4]

    On the Performance of STAR-RIS-Aided NOMA at Finite Blocklength,

    F. Karim et al. , “On the Performance of STAR-RIS-Aided NOMA at Finite Blocklength,” IEEE Wireless Commun. Lett. , vol. 12, no. 5, pp. 868–872, Feb. 2023

    work page 2023

  5. [5]

    Performance Analysis of Uplink Rate-Splitting Multiple Access with Hybrid ARQ,

    Y . Liu et al. , “Performance Analysis of Uplink Rate-Splitting Multiple Access with Hybrid ARQ,” IEEE Trans. Wireless Commun. , vol. 23, no. 10, pp. 14 201–14 214, Oct. 2024

    work page 2024

  6. [6]

    A Performance Analysis for Multi-Ris-Assisted Full Duplex Wireless Communication System,

    F. Karim et al. , “A Performance Analysis for Multi-Ris-Assisted Full Duplex Wireless Communication System,” in 2022 IEEE International Conference on Acoustics, Speech and Signal Processing (ICA SSP), May 2022, pp. 5313–5317

    work page 2022

  7. [7]

    Robust beamforming design for rsma-integrated full- duplex communications: Energy and spectral efficiency trad e-off,

    R. Allu et al. , “Robust beamforming design for rsma-integrated full- duplex communications: Energy and spectral efficiency trad e-off,” IEEE Trans. Green Commun. Net. , pp. 1–1, Sep. 2024

    work page 2024

  8. [8]

    QoS-aware performance analysis of full-duplex RSMA vehicle road cooperation systems,

    X. Li et al. , “QoS-aware performance analysis of full-duplex RSMA vehicle road cooperation systems,” IEEE Internet Things J. , vol. 11, no. 22, pp. 36 053–36 065, Nov. 2024

    work page 2024

  9. [9]

    In-Band Full-Duplex Wireless: Challenges and Opportunities,

    A. Sabharwal et al. , “In-Band Full-Duplex Wireless: Challenges and Opportunities,” IEEE Journal on Selected Areas in Communications , vol. 32, no. 9, pp. 1637–1652, Jin. 2014

    work page 2014

  10. [10]

    Performance of IRS-Aided FD Two-Way Communi- cation Network With Imperfect SIC,

    D. Kumar et al. , “Performance of IRS-Aided FD Two-Way Communi- cation Network With Imperfect SIC,” IEEE Trans. V eh. Tech., vol. 72, no. 4, pp. 5491–5496, Apr. 2023

    work page 2023

  11. [11]

    Performance of SWIPT-Enabled FD TWR Network With H ard- ware Impairments and Imperfect CSI,

    ——, “Performance of SWIPT-Enabled FD TWR Network With H ard- ware Impairments and Imperfect CSI,” IEEE Systems Journal , vol. 17, no. 1, pp. 1224–1234, Mar. 2023

    work page 2023

  12. [12]

    SWIPT-Enabled RSMA Downlink Networks with Imperfect CSI and SIC,

    F. Karim et al. , “SWIPT-Enabled RSMA Downlink Networks with Imperfect CSI and SIC,” in 2024 IEEE Wireless Communications and Networking Conference (WCNC) , Apr. 2024, pp. 1–6

    work page 2024

  13. [13]

    I. S. Gradshteyn et al. , Table of Integrals, Series, and Products , 7th ed. San Diego, CA, USA: Academic Press, 2007

    work page 2007