Joint Trajectory and Resource Optimization for Dual-aerial ARIS-assisted NOMA-TNT Networks
Pith reviewed 2026-05-10 14:56 UTC · model grok-4.3
The pith
Jointly optimizing UAV and HAP trajectories with active RIS coefficients and beamforming maximizes sum-rate in dual-aerial NOMA ITNTNs.
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
In a NOMA-based integrated terrestrial and non-terrestrial network assisted by dual-aerial active reconfigurable intelligent surfaces, jointly optimizing transmit beamforming, ARIS coefficients, and the 3D trajectories of the UAV and HAP maximizes average sum-rate subject to power, unit-modulus, amplification, and mobility constraints; the resulting block-coordinate algorithm converges to a stationary point and delivers an 8.44 percent sum-rate improvement over passive-RIS benchmarks under the same power limits.
What carries the argument
Block coordinate descent framework that alternates WMMSE beamforming, manifold-based Riemannian conjugate gradient for ARIS phases, successive convex approximation for amplification factors, and first-order linearization for UAV and HAP trajectories.
If this is right
- The dual-aerial ARIS configuration provides an average 8.44 percent sum-rate gain over passive RIS under identical power budgets.
- Joint communication-mobility optimization outperforms schemes that treat trajectory design and resource allocation separately.
- The block coordinate descent procedure is guaranteed to converge to a stationary point of the non-convex problem.
- The design respects practical constraints on ARIS power consumption, unit-modulus phase shifts, and platform mobility limits.
Where Pith is reading between the lines
- Extending the same joint-optimization logic to time-varying user locations or additional aerial platforms could further improve coverage in remote regions.
- The framework naturally raises the question of whether energy or latency can be traded against sum-rate within the same BCD structure.
- Because the gain is attributed to active amplification and mobility coupling, similar benefits may appear in other non-terrestrial scenarios that already use movable surfaces.
Load-bearing premise
A fixed successive interference cancellation order for NOMA users remains effective as the UAV and HAP move and change the channel conditions.
What would settle it
A simulation in which the reported sum-rate gain vanishes when the ARIS amplification factors are forced to unity or when the UAV and HAP trajectories are held fixed instead of jointly optimized.
Figures
read the original abstract
Integrated terrestrial and non-terrestrial networks (ITNTNs) are envisioned as a key paradigm for sixth-generation (6G) wireless systems, enabling seamless global connectivity. In this paper, we investigate a dual-aerial active reconfigurable intelligent surface (ARIS)-assisted non-orthogonal multiple access (NOMA)-based ITNTN, where a terrestrial base station (TBS) and a satellite (SAT) simultaneously serve terrestrial and satellite users with the aid of a UAV-mounted ARIS and a HAP-mounted ARIS. Users are multiplexed via power-domain NOMA with a predefined SIC decoding order. We formulate an average sum-rate maximization problem by jointly optimizing transmit beamforming, ARIS coefficients, and the 3D trajectories of the UAV and HAP, subject to power, unit-modulus, ARIS power, and mobility constraints. The problem is highly non-convex due to coupled variables, nonlinear SINR expressions, ARIS amplification, and trajectory-dependent channels. To address this, a block coordinate descent (BCD)-based framework is proposed. Specifically, beamforming is optimized via WMMSE, ARIS phase shifts via a manifold-based RCG method, amplification factors via SCA, and trajectories via first-order approximations. The proposed algorithm is guaranteed to converge to a stationary point. Simulation results demonstrate that the proposed design achieves significant performance gains over benchmark schemes. In particular, it provides an average sum-rate improvement of approximately $8.44\%$ over passive RIS under given power constraints, highlighting the benefits of dual-aerial ARIS and joint communication-mobility optimization.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The manuscript investigates a dual-aerial active RIS (ARIS)-assisted NOMA system in integrated terrestrial-non-terrestrial networks, with a terrestrial base station and satellite serving users via UAV- and HAP-mounted ARIS. It formulates an average sum-rate maximization problem jointly optimizing transmit beamforming, ARIS coefficients, and 3D trajectories subject to power, unit-modulus, ARIS power, and mobility constraints. A BCD framework is proposed: WMMSE for beamforming, manifold-based RCG for phase shifts, SCA for amplification factors, and first-order approximations for trajectories. The algorithm is shown to converge to a stationary point, and simulations report an approximately 8.44% sum-rate gain over passive RIS.
Significance. If the simulation results hold under rigorous validation, the work offers a concrete algorithmic framework for handling non-convex joint communication-mobility optimization in 6G ITNTN scenarios with active RIS, highlighting potential benefits of dual-aerial platforms over passive alternatives. The explicit convergence guarantee to a stationary point and the block-wise decomposition are positive technical contributions, though the moderate level of simulation transparency and the fixed NOMA assumption reduce the strength of the performance claims.
major comments (2)
- [Abstract and System Model] Abstract and System Model: The power-domain NOMA scheme uses a predefined SIC decoding order that is fixed prior to optimization. This choice directly determines the structure of the nonlinear SINR expressions and the power allocation constraints. Because the overall problem is already non-convex due to coupled trajectory-dependent channels and ARIS amplification, fixing the order a priori can produce a stationary point that is suboptimal relative to a jointly optimized decoding order, which weakens the fairness of the benchmark comparisons and the attribution of the reported 8.44% gain specifically to the dual-aerial ARIS and joint mobility design.
- [Simulation Results] Simulation Results: The claim of an average 8.44% sum-rate improvement over passive RIS (and other benchmarks) is presented without explicit details on the simulation parameters (e.g., number of users, exact transmit power budgets, channel models, noise variances, or mobility constraints), the precise definition of the benchmark schemes, or empirical checks on the accuracy of the first-order trajectory approximations and SCA relaxations. This absence makes it difficult to assess the robustness or reproducibility of the central performance claim.
minor comments (2)
- [Proposed Algorithm] The BCD algorithm description would benefit from a concise pseudocode listing the block updates and stopping criteria to improve readability.
- [Problem Formulation and Algorithm] Notation for ARIS amplification factors and phase-shift matrices should be checked for consistency between the problem formulation and the manifold optimization subsection.
Simulated Author's Rebuttal
We thank the referee for the constructive comments, which help clarify key aspects of our work. We respond to each major comment below and indicate the revisions we will incorporate.
read point-by-point responses
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Referee: [Abstract and System Model] Abstract and System Model: The power-domain NOMA scheme uses a predefined SIC decoding order that is fixed prior to optimization. This choice directly determines the structure of the nonlinear SINR expressions and the power allocation constraints. Because the overall problem is already non-convex due to coupled trajectory-dependent channels and ARIS amplification, fixing the order a priori can produce a stationary point that is suboptimal relative to a jointly optimized decoding order, which weakens the fairness of the benchmark comparisons and the attribution of the reported 8.44% gain specifically to the dual-aerial ARIS and joint mobility design.
Authors: We appreciate the referee highlighting the implications of the fixed SIC decoding order. The manuscript adopts a predefined order based on sorted effective channel gains, a standard assumption in power-domain NOMA optimization to preserve tractability of the already non-convex problem involving coupled trajectories, ARIS amplification, and beamforming. Jointly optimizing the decoding order would introduce discrete combinatorial decisions that render the BCD framework intractable. All benchmark schemes, including passive RIS variants, employ the identical fixed-order assumption, so the reported performance differences remain attributable to the dual-aerial ARIS and joint mobility optimization. We will add a short discussion of this modeling choice and its limitations in the revised manuscript. revision: partial
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Referee: [Simulation Results] Simulation Results: The claim of an average 8.44% sum-rate improvement over passive RIS (and other benchmarks) is presented without explicit details on the simulation parameters (e.g., number of users, exact transmit power budgets, channel models, noise variances, or mobility constraints), the precise definition of the benchmark schemes, or empirical checks on the accuracy of the first-order trajectory approximations and SCA relaxations. This absence makes it difficult to assess the robustness or reproducibility of the central performance claim.
Authors: We acknowledge that the initial presentation of the simulation results lacked sufficient explicit detail for full reproducibility. The manuscript contains a dedicated simulation section that specifies all parameters and benchmark definitions; we will reorganize this section to include a consolidated parameter table, explicit descriptions of each benchmark scheme, and additional numerical checks confirming the accuracy of the first-order trajectory approximations and SCA relaxations. These changes will be made in the revised version. revision: yes
Circularity Check
No significant circularity; results computed directly from optimized variables
full rationale
The paper formulates a non-convex sum-rate maximization problem and solves it via a BCD framework using standard subproblem solvers (WMMSE for beamforming, manifold RCG for phases, SCA for amplification, first-order approx for trajectories). The 8.44% gain is obtained by direct evaluation of the objective on the converged variables in simulations, with no fitted parameters renamed as predictions and no self-citation chain supporting the core claims. The predefined SIC order is a modeling assumption, not a definitional loop. The derivation remains self-contained against external benchmarks.
Axiom & Free-Parameter Ledger
free parameters (1)
- SIC decoding order
axioms (2)
- domain assumption The optimization problem is highly non-convex due to coupled variables, nonlinear SINR expressions, ARIS amplification, and trajectory-dependent channels
- standard math The proposed algorithm is guaranteed to converge to a stationary point
Reference graph
Works this paper leans on
-
[1]
F. Khennoufa, K. Abdellatif, H. Yanikomeroglu, M. Ozturk, T. Elganimi, F. Kara, and K. Rabie, “A multi-layer Non-Terrestrial Networks architecture for 6G and beyond under realistic conditions and with practical limitations,” IEEE Internet Things Mag., vol. 8, no. 5, pp. 136–143, Sep. 2025
work page 2025
-
[2]
Resource Optimization for Integrated Terrestrial Non-Terrestrial Networks Involving IRS,
W. U. Khan, A. Mahmood, E. Lagunas, M. A. Jamshed, S. Chatzinotas, and B. Ottersten, “Resource Optimization for Integrated Terrestrial Non-Terrestrial Networks Involving IRS,” in Proc. IEEE Globecom Workshops (GC Wkshps), Dec 2023, pp. 1710–1715
work page 2023
-
[3]
H. Yu, T. Taleb, K. Samdanis, and J. Song, “Toward Supporting Holographic Services Over Deterministic 6G Integrated Terrestrial and Non-Terrestrial Networks,” IEEE Netw., vol. 38, no. 1, pp. 262–271, Jan 2024
work page 2024
-
[4]
Integrating Terrestrial and Non-Terrestrial Networks: 3D Oppor- tunities and Challenges,
G. Geraci, D. López-Pérez, M. Benzaghta, and S. Chatzinotas, “Integrating Terrestrial and Non-Terrestrial Networks: 3D Oppor- tunities and Challenges,” IEEE Commun. Mag., vol. 61, no. 4, pp. 42–48, April 2023
work page 2023
-
[5]
MIMO satellite communication systems: A survey from the PHY layer perspective,
J. Heo, S. Sung, H. Lee, I. Hwang, and D. Hong, “MIMO satellite communication systems: A survey from the PHY layer perspective,” IEEE Commun. Surveys Tuts., vol. 25, no. 3, pp. 1543–1570, thirdquarter 2023. 14
work page 2023
-
[6]
Evolution of Non- Terrestrial Networks From 5G to 6G: A Survey,
M. M. Azari, S. Solanki, S. Chatzinotas, O. Kodheli, H. Sallouha, A. Colpaert, J. F. Mendoza Montoya, S. Pollin, A. Haqiqatnejad, A. Mostaani, E. Lagunas, and B. Ottersten, “Evolution of Non- Terrestrial Networks From 5G to 6G: A Survey,” IEEE Commun. Surveys Tuts., vol. 24, no. 4, pp. 2633–2672, Fourthquarter 2022
work page 2022
-
[7]
M. Di Renzo, A. Zappone, M. Debbah, M.-S. Alouini, C. Yuen, J. de Rosny, and S. Tretyakov, “Smart radio environments empow- ered by Reconfigurable Intelligent Surfaces: How it works, state of research, and the road ahead,” IEEE J. Sel. Areas Commun., vol. 38, no. 11, pp. 2450–2525, Nov 2020
work page 2020
-
[8]
C. Pan, H. Ren, K. Wang, J. F. Kolb, M. Elkashlan, M. Chen, M. Di Renzo, Y. Hao, J. Wang, A. L. Swindlehurst, X. You, and L. Hanzo, “Reconfigurable Intelligent Surfaces for 6G Systems: Principles, Applications, and Research Directions,” IEEE Com- mun. Mag., vol. 59, no. 6, pp. 14–20, June 2021
work page 2021
-
[9]
Weighted sum-rate maximization for reconfigurable intelligent surface aided wireless networks,
H. Guo, Y.-C. Liang, J. Chen, and E. G. Larsson, “Weighted sum-rate maximization for reconfigurable intelligent surface aided wireless networks,” IEEE Trans. Wireless Commun., vol. 19, no. 5, pp. 3064–3076, May 2020
work page 2020
-
[10]
Reconfigurable Intelligent Surfaces for Energy Efficiency in Wireless Communication,
C. Huang, A. Zappone, G. C. Alexandropoulos, M. Debbah, and C. Yuen, “Reconfigurable Intelligent Surfaces for Energy Efficiency in Wireless Communication,” IEEE Trans. Wireless Commun., vol. 18, no. 8, pp. 4157–4170, Aug 2019
work page 2019
-
[11]
X. Ma, S. Guo, H. Zhang, Y. Fang, and D. Yuan, “Joint Beamforming and Reflecting Design in Reconfigurable Intelligent Surface-Aided Multi-User Communication Systems,” IEEE Trans. Wireless Commun., vol. 20, no. 5, pp. 3269–3283, May 2021
work page 2021
-
[12]
Active Reconfig- urable Intelligent Surface-Aided Wireless Communications,
R. Long, Y.-C. Liang, Y. Pei, and E. G. Larsson, “Active Reconfig- urable Intelligent Surface-Aided Wireless Communications,” IEEE Trans. Wireless Commun., vol. 20, no. 8, pp. 4962–4975, Aug 2021
work page 2021
-
[13]
Optimization of Active RIS Configurations in SIM Architectures with Mutual Coupling,
H. Mandalika, S. Singh, A. Rosyidah, K. Singh, and H. Shin, “Optimization of Active RIS Configurations in SIM Architectures with Mutual Coupling,” IEEE Wirel. Commun. Lett., pp. 1–1, 2026
work page 2026
-
[14]
NOMA-Enhanced Active RIS-Aided MISO ISAC System Under NTN With Hardware Impairment,
S. Mondal, K. Singh, C.-P. Li, and Z. Ding, “NOMA-Enhanced Active RIS-Aided MISO ISAC System Under NTN With Hardware Impairment,” IEEE Trans. Commun., vol. 74, pp. 4629–4645, 2026
work page 2026
-
[15]
Active RIS vs. Passive RIS: Which Will Prevail in 6G?
Z. Zhang, L. Dai, X. Chen, C. Liu, F. Yang, R. Schober, and H. V. Poor, “Active RIS vs. Passive RIS: Which Will Prevail in 6G?” IEEE Trans. Commun., vol. 71, no. 3, pp. 1707–1725, March 2023
work page 2023
-
[16]
S. Li, B. Duo, X. Yuan, Y.-C. Liang, and M. Di Renzo, “Re- configurable Intelligent Surface Assisted UA V Communication: Joint Trajectory Design and Passive Beamforming,” IEEE Wirel. Commun. Lett, vol. 9, no. 5, pp. 716–720, May 2020
work page 2020
-
[17]
N. Agrawal, A. Bansal, K. Singh, and C.-P. Li, “Performance Eval- uation of RIS-Assisted UA V-Enabled Vehicular Communication System With Multiple Non-Identical Interferers,” IEEE Trans. Intell. Transp. Syst., vol. 23, no. 7, pp. 9883–9894, July 2022
work page 2022
-
[18]
Performance Analysis of RIS-Assisted UA V Communication Systems,
L. Yang, P. Li, F. Meng, and S. Yu, “Performance Analysis of RIS-Assisted UA V Communication Systems,” IEEE Trans. Veh. Technol., vol. 71, no. 8, pp. 9078–9082, Aug 2022
work page 2022
-
[19]
H. Mei, K. Yang, Q. Liu, and K. Wang, “3D-trajectory and phase- shift design for RIS-assisted UA V systems using deep reinforce- ment learning,” IEEE Trans. Veh. Technol., vol. 71, no. 3, pp. 3020–3029, March 2022
work page 2022
-
[20]
Joint UA V Trajectory and Beamforming Designs for RIS-Assisted MIMO System,
S. Li, H. Du, D. Zhang, and K. Li, “Joint UA V Trajectory and Beamforming Designs for RIS-Assisted MIMO System,” IEEE Trans. Veh. Technol., vol. 73, no. 4, pp. 5378–5392, April 2024
work page 2024
-
[21]
S. Alfattani, W. Jaafar, H. Yanikomeroglu, and A. Yongaçoglu, “Multimode High-Altitude Platform Stations for Next-Generation Wireless Networks: Selection Mechanism, Benefits, and Potential Challenges,” IEEE Veh. Technol. Mag, vol. 18, no. 3, pp. 20–28, Sep. 2023
work page 2023
-
[22]
T.-N. Tran, Y. Jeon, H. Yu, and T. Kim, “Joint Resource Allocation and Power Control in Rate-Splitting Multiple Access- Based Integrated Terrestrial and Non-Terrestrial Networks With HAP Assistance,” IEEE Access, vol. 13, pp. 142 203–142 220, 2025
work page 2025
-
[23]
Power- Domain Non-Orthogonal Multiple Access (NOMA) in 5G Systems: Potentials and Challenges,
S. M. R. Islam, N. A vazov, O. A. Dobre, and K.-s. Kwak, “Power- Domain Non-Orthogonal Multiple Access (NOMA) in 5G Systems: Potentials and Challenges,” IEEE Commun. Surveys Tuts., vol. 19, no. 2, pp. 721–742, Secondquarter 2017
work page 2017
-
[24]
S. Singh, K. Singh, S. K. Singh, F.-S. Tseng, and O. A. Dobre, “Holographic active RIS-enhanced secure uplink NOMA-aided near-field communications under channel uncertainties,” IEEE Trans. Wireless Commun., vol. 25, pp. 12 391–12 406, 2026
work page 2026
-
[25]
Re- configurable Intelligent Surface Aided NOMA Networks,
T. Hou, Y. Liu, Z. Song, X. Sun, Y. Chen, and L. Hanzo, “Re- configurable Intelligent Surface Aided NOMA Networks,” IEEE J. Sel. Areas Commun., vol. 38, no. 11, pp. 2575–2588, Nov 2020
work page 2020
-
[26]
Reconfigurable Intelligent Surface-Assisted Non-Orthogonal Multiple Access,
G. Yang, X. Xu, Y.-C. Liang, and M. D. Renzo, “Reconfigurable Intelligent Surface-Assisted Non-Orthogonal Multiple Access,” IEEE Trans. Wireless Commun., vol. 20, no. 5, pp. 3137–3151, May 2021
work page 2021
-
[27]
On Performance of RIS-NOMA Assisted Heterogeneous ISAC Networks,
A. Singh Parihar, K. Singh, V. Bhatia, C.-P. Li, and Z. Ding, “On Performance of RIS-NOMA Assisted Heterogeneous ISAC Networks,” IEEE Trans. Cogn. Commun. Netw., vol. 12, pp. 3088– 3103, 2026
work page 2026
-
[28]
Active RIS Aided NOMA for HAP-MISO Systems,
P. Ji, L. Jiang, C. He, Z. Lian, and D. He, “Active RIS Aided NOMA for HAP-MISO Systems,” IEEE Wirel. Commun. Lett., vol. 13, no. 8, pp. 2170–2174, Aug 2024
work page 2024
-
[29]
Design of RIS-UA V- Assisted LEO Satellite Constellation Communication,
W. Yao, X. Chen, Q. Wang, and X. Peng, “Design of RIS-UA V- Assisted LEO Satellite Constellation Communication,” IEEE Trans. Commun., vol. 73, no. 12, pp. 15 656–15 671, 2025
work page 2025
-
[30]
Study on Channel Model for Frequencies from 0.5 to 100 GHz,
3GPP, “Study on Channel Model for Frequencies from 0.5 to 100 GHz,” 3rd Generation Partnership Project, Technical Report TR 38.901, 2020, technical Specification Group Radio Access Network
work page 2020
-
[31]
P.-A. Absil, R. Mahony, and R. Sepulchre, Opti- mization Algorithms on Matrix Manifolds. Princeton: Princeton University Press, 2008. [Online]. A vailable: https://doi.org/10.1515/9781400830244
-
[32]
S. Boyd and L. Vandenberghe, Convex Optimization. Cambridge University Press, 2004
work page 2004
-
[33]
IRS-Assisted Secure UA V Transmission via Joint Trajectory and Beamforming Design,
X. Pang, N. Zhao, J. Tang, C. Wu, D. Niyato, and K.-K. Wong, “IRS-Assisted Secure UA V Transmission via Joint Trajectory and Beamforming Design,” IEEE Trans. Commun., vol. 70, no. 2, pp. 1140–1152, Feb 2022
work page 2022
-
[34]
X. Tang, Y. Jiang, R. Zhang, Q. Du, J. Liu, and N. Liu, “Energy-Efficient Integrated Communication and Computation via Nonterrestrial Networks With Uncertainty Awareness,” IEEE Internet Things J., vol. 12, no. 17, pp. 35 165–35 178, Sep. 2025
work page 2025
-
[35]
Solutions for NR to Support Non-Terrestrial Networks (NTN),
3GPP, “Solutions for NR to Support Non-Terrestrial Networks (NTN),” 3rd Generation Partnership Project, Technical Report TR 38.821, 2020, technical Specification Group Radio Access Network
work page 2020
discussion (0)
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