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arxiv: 2606.28921 · v1 · pith:PRDV57FSnew · submitted 2026-06-27 · 📡 eess.SP

PASS-Assisted RSMA under Imperfect SIC: Joint Antenna Activation and Resource Allocation

Saeid Pakravan , Imene Trigui , Wessam Ajib , Wei-Ping Zhu This is my paper

Pith reviewed 2026-06-30 08:51 UTC · model grok-4.3

classification 📡 eess.SP
keywords rate-splitting multiple accesspinching antenna systemimperfect successive interference cancellationmax-min rate optimizationantenna activationpower allocationsuccessive convex approximation
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The pith

A two-stage framework jointly optimizes antenna activation and resource allocation to improve fairness in pinching antenna assisted RSMA when successive interference cancellation is imperfect.

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

This paper examines rate-splitting multiple access in a pinching antenna system where imperfect successive interference cancellation leaves residual common-stream interference that affects private-stream decoding. It sets up a max-min rate optimization that designs antenna activation, common-rate allocation, and power allocation together to promote fairness among users. The resulting mixed-integer non-convex problem is handled by a two-stage method that first selects antennas greedily according to channel quality and then applies successive convex approximation to allocate rates and power. A reader would care because real systems rarely achieve perfect cancellation, and the approach shows how to maintain balanced performance without assuming ideal conditions.

Core claim

The paper establishes that explicitly modeling residual common-stream interference and solving the max-min fairness problem through greedy channel-aware antenna activation followed by successive convex approximation-based resource allocation yields effective performance in PASS-assisted RSMA networks under imperfect SIC.

What carries the argument

The two-stage framework of greedy channel-aware antenna activation followed by successive convex approximation for joint common-rate and power allocation.

Load-bearing premise

The two-stage framework produces a solution close to the global optimum for the max-min rate problem without the greedy choice or convex approximations introducing large sub-optimality.

What would settle it

Solving small instances of the original mixed-integer problem to global optimality via exhaustive search or branch-and-bound and comparing the resulting max-min rates against those from the two-stage method would show whether the approximations cause significant performance loss.

Figures

Figures reproduced from arXiv: 2606.28921 by Imene Trigui, Saeid Pakravan, Wei-Ping Zhu, Wessam Ajib.

Figure 1
Figure 1. Figure 1: Illustration of the proposed PASS-assisted RSMA system model. [PITH_FULL_IMAGE:figures/full_fig_p002_1.png] view at source ↗
Figure 2
Figure 2. Figure 2: Minimum user rate versus (a) maximum transmit power [PITH_FULL_IMAGE:figures/full_fig_p005_2.png] view at source ↗
read the original abstract

The performance of rate-splitting multiple access (RSMA) can be severely affected by imperfect successive interference cancellation (SIC) in practical wireless systems. This paper investigates a downlink pinching antenna system (PASS)-assisted RSMA network under imperfect SIC, where residual common-stream interference is explicitly incorporated into private-stream decoding. To improve user fairness, a max-min rate optimization problem is formulated through the joint design of antenna activation, common-rate allocation, and power allocation. The resulting mixed-integer non-convex problem is addressed using a two-stage framework that combines greedy channel-aware antenna activation with successive convex approximation (SCA)-based resource allocation. Numerical results demonstrate the effectiveness of the proposed framework in improving fairness under imperfect SIC.

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 / 2 minor

Summary. The manuscript formulates a max-min rate optimization for a downlink PASS-assisted RSMA network under imperfect SIC (with explicit residual common-stream interference at private-stream decoders). The mixed-integer non-convex problem is solved by a two-stage heuristic: greedy channel-aware antenna activation followed by SCA-based joint common-rate and power allocation. Numerical results are presented to claim improved user fairness relative to baselines.

Significance. If the reported fairness gains hold under a validated solver, the work would provide a concrete design for practical RSMA in pinching-antenna systems that accounts for imperfect SIC, an issue that limits conventional RSMA performance. The explicit modeling of residual interference and the joint antenna/resource formulation are potentially useful contributions.

major comments (2)
  1. [Numerical Results / Proposed Algorithm (Section IV)] The central claim rests on numerical results from the two-stage solver. No small-instance exhaustive enumeration, duality-gap bound, or comparison against a global solver (e.g., branch-and-bound on the mixed-integer problem) is provided to quantify the optimality gap of the greedy antenna selection or the SCA fixed point; without this, fairness improvements cannot be confidently attributed to the RSMA/PASS design rather than solver artifacts.
  2. [Two-Stage Framework (Section III)] The greedy channel-aware antenna activation step selects a subset without backtracking or exhaustive search over the combinatorial space; the manuscript does not analyze how this choice interacts with the subsequent SCA stage or whether alternative activation heuristics materially alter the max-min rate under imperfect SIC.
minor comments (2)
  1. [Numerical Results] Simulation parameters (noise variance, channel model, number of antennas/users, imperfect-SIC residual factor) should be stated explicitly in the numerical-results section rather than referenced only in figure captions.
  2. [System Model] Notation for the residual interference term after imperfect SIC should be introduced once in the system model and used consistently in the rate expressions.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for the constructive comments on validation and analysis of the proposed heuristic. We address each major comment below with clarifications and indicate where revisions will be made.

read point-by-point responses

  1. Referee: [Numerical Results / Proposed Algorithm (Section IV)] The central claim rests on numerical results from the two-stage solver. No small-instance exhaustive enumeration, duality-gap bound, or comparison against a global solver (e.g., branch-and-bound on the mixed-integer problem) is provided to quantify the optimality gap of the greedy antenna selection or the SCA fixed point; without this, fairness improvements cannot be confidently attributed to the RSMA/PASS design rather than solver artifacts.

    Authors: We agree that the lack of a global optimality benchmark limits strong claims about the heuristic's gap. The mixed-integer non-convex problem is NP-hard, making branch-and-bound infeasible for the system sizes considered due to prohibitive complexity. However, we will add exhaustive enumeration results for small instances (e.g., few antennas/users) in the revision to quantify the greedy step's gap and better attribute fairness gains. This addresses the concern without misrepresenting the practical nature of the approach. revision: partial

  2. Referee: [Two-Stage Framework (Section III)] The greedy channel-aware antenna activation step selects a subset without backtracking or exhaustive search over the combinatorial space; the manuscript does not analyze how this choice interacts with the subsequent SCA stage or whether alternative activation heuristics materially alter the max-min rate under imperfect SIC.

    Authors: The greedy activation prioritizes low complexity and channel awareness, which is essential for PASS systems. We acknowledge the absence of interaction analysis and alternative comparisons. In the revision, we will include a discussion of the greedy-SCA interplay and add numerical comparisons with alternatives (e.g., random or exhaustive for small cases) to show robustness under imperfect SIC. revision: yes

Circularity Check

0 steps flagged

No circularity; heuristic solver validated by simulation without self-referential reduction

full rationale

The paper formulates a max-min rate optimization as a mixed-integer non-convex problem and solves it via a two-stage heuristic (greedy antenna activation + SCA). Numerical results are obtained by executing this solver on simulated channels. No derivation step reduces a claimed prediction or first-principles result to its own fitted inputs by construction, nor does any load-bearing premise rest on a self-citation chain. The central claim is empirical performance of the heuristic under imperfect SIC, which is externally falsifiable via simulation benchmarks and does not exhibit the enumerated circularity patterns.

Axiom & Free-Parameter Ledger

1 free parameters · 2 axioms · 0 invented entities

Review based on abstract only; the framework relies on standard wireless communication models and optimization assumptions not detailed in the provided text.

free parameters (1)
  • Power allocation variables
    Common and private stream powers are decision variables in the optimization and are solved numerically for given channels.
axioms (2)
  • domain assumption Imperfect SIC leaves residual common-stream interference that affects private-stream decoding
    Explicitly incorporated into the model as stated in the abstract.
  • ad hoc to paper The mixed-integer non-convex max-min rate problem can be addressed via greedy antenna activation plus SCA without large optimality gap
    The two-stage framework is presented as effective without further justification in the abstract.

pith-pipeline@v0.9.1-grok · 5658 in / 1686 out tokens · 47246 ms · 2026-06-30T08:51:37.695295+00:00 · methodology

discussion (0)

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Reference graph

Works this paper leans on

16 extracted references · 2 canonical work pages · 2 internal anchors

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