Pith. sign in

REVIEW 3 major objections 5 minor 53 references

Time-Continuous Frequency Allocation for Feeder Links of Mega Constellations with Multi-Antenna Gateway Stations

T0 review · 3 major / 5 minor · reviewed 2026-08-15 · deepseek-v4-flash

Pith's one-line read Graph-coloring frequency allocation can keep mega-LEO feeder links within the regulatory interference limit while switching frequencies only about 1.5 percent of the time.

desk verdict A real engineering problem and a plausible toolkit, but the P1-to-P2 graph transformation is circular as written and the sub-1% link-failure claims rest on an unverified equivalence. read the letter →

arxiv 2505.12429 v1 pith:UGEJI6YE submitted 2025-05-18 eess.SY cs.SYeess.SP

classification eess.SYcs.SYeess.SP
keywords graphcoloringfrequencyallocationfeederlinksmegaLEOconstellationsmulti-antennagatewaystationsinterferencemitigationtime-continuouslist
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

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

The reading

The paper tries to establish that the interference problem for feeder links in mega LEO systems with multi-antenna gateway stations can be reduced to graph coloring with negligible performance loss, and that the resulting frequency allocations can be held stable over time. It develops an adaptive per-link threshold that turns the aggregate interference constraint into graph edges, then gives two coloring algorithms—Generalized Global and Clique-Based Tabu Search—that exploit the fact that satellites serving the same gateway form a clique. The paper reports average link failure rates below 1 percent on a simulated 34,396-satellite Starlink constellation, and a time-continuous variant that stays below 1.1 percent failure at a frequency switching rate of only 0.015. If correct, this makes system-level interference mitigation for mega constellations computationally practical at low switching overhead.

What carries the argument

The load-bearing object is the time-varying interference graph $G(t)$, whose vertices are the working satellites and whose edges are placed by an adaptive threshold: an interfering link becomes an edge when its single-link interference exceeds a per-satellite threshold chosen so that the aggregate interference of every link stays under the regulatory limit. This edge construction is what converts the original integer nonlinear link-failure minimization into a conflict-minimization coloring problem. The second mechanism is the clique partition of $G(t)$: satellites serving the same multi-antenna gateway form a clique or quasi-clique, and Lemma 1 guarantees that coloring each clique with all distinct colors removes every intra-gateway conflict. GG and CTS solve the coloring at scale, and the time-continuous variants freeze the colors of satellites that keep their gateway and switch a constrained satellite's color only with a probability proportional to the number of conflicts it would remove; this probabilistic switch is the mechanism that holds the frequency switching rate near 0.015.

What would settle it

Re-run the edge-construction rule on one time slot with two different allocations—CTS's output and a random assignment—and compare the resulting edge sets; if they differ materially, the graph is not a fixed interference topology and the reported link-failure rates cannot be attributed solely to the coloring solutions.

Watch

Extended reading notes

Core claim

The central claim is that the aggregate-interference constraint on feeder links—the ITU requirement that each link's interference-to-noise ratio stay below -12.2 dB—can be converted into a graph-coloring problem with almost no loss, provided the graph edges are drawn with an adaptive per-satellite threshold rather than a fixed one. The paper identifies a structural fact that makes the coloring easy: all satellites selected by the same multi-antenna gateway point their antennas at the same location, so they form a clique or quasi-clique of size equal to the number of gateway antennas. Assigning distinct subchannels inside each clique eliminates all intra-gateway interference by Lemma 1, and a tabu search over these clique-structured initial colorings removes most inter-gateway interference as well. On a simulated Starlink constellation of 34,396 satellites, the paper reports that these methods keep average link failure below 1 percent, with the clique-based variant reaching 0.89 percent and outperforming a strong general-purpose graph-coloring algorithm at lower runtime; the time-continuous modification extends the same protection to a frequency switching rate as low as 0.015.

Load-bearing premise

The interference graph is defined using the very frequency assignment the coloring procedure is supposed to produce, so the reduction from link-failure minimization to graph coloring is only well-posed if the graph's edges are read as potential interference that does not depend on the current allocation.

Editorial extensions

If this is right

  • If the paper's results are right, a mega-constellation operator can hold average feeder-link failure below about 1 percent using only as many subchannels as the gateway has antennas, with the clique-based CTS variant reaching 0.89 percent on the simulated 34,396-satellite Starlink system.
  • The time-continuous variants preserve that protection at low switching cost: TCFA-CTS stays below 1.1 percent link failure at a frequency switching rate of 0.015, which the paper argues makes feeder-link stability practical without heavy signaling overhead.
  • The two decomposition methods scale the approach to full mega constellations: connected-component decomposition saves about half the execution time, and gateway-station clustering saves about 70 percent, with CTS experiencing almost no interference-mitigation loss.
  • Because the paper bounds capacity loss once the ITU interference constraint is met, graph-coloring IM nearly reaches the interference-free capacity ceiling; the paper reports system capacity degradation below 0.1 percent for CTS.
  • List-coloring-based vacant subchannel reuse can then raise system capacity by about 6 percent at 20 antennas per gateway and 17 percent at 25 antennas, without adding conflicts.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

  • The paper leaves implicit that the clique partition is a geometric fact rather than a Starlink-specific one: any gateway with several antennas pointed at nearby satellites generates near-cliques, so CTS should transfer to other mega constellations and to multi-beam gateway architectures.
  • A testable extension would replace the binary adaptive threshold with continuous edge weights and solve a weighted coloring problem; the small gap between CTS and the direct integer optimization suggests that weighted conflict minimization could close it while keeping the polynomial-time scaling.
  • The switching probability is a tunable knob: an operator could adapt it online to honor a hard frequency-switching budget, which the paper does not explore.
  • A stress test for coexistence would apply the method when two operators' satellites share the same gateway region, since then the clean per-gateway clique partition is broken and the method's performance is not covered by the paper's simulations.
Share X Bluesky LinkedIn Reddit HN

Signed reviews

No signed human review yet.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, and a circularity audit.

Referee Report

3 major / 5 minor

Summary. The paper addresses interference mitigation for feeder links of mega LEO satellite constellations with multi-antenna gateway stations (MAGSs). It models the system, formulates an aggregate I/N link-failure minimization problem P1, and transforms it into a graph coloring problem P2 with an adaptive interference threshold. Two coloring algorithms are proposed: Generalized Global (GG) and Clique-Based Tabu Search (CTS), together with time-continuous variants (TCFA-GG, TCFA-CTS), two constellation decomposition methods, and a list-coloring-based vacant subchannel utilization scheme. Simulations on a Starlink Gen1/Gen2 constellation with 34,396 satellites report average link failure rates below 1% for GG, CTS, and HEAD, with TCFA-CTS below 1.1% at a frequency switching rate of 0.015.

Significance. If the core formulation is valid, the paper makes a significant engineering contribution: it proposes scalable, low-complexity frequency allocation for a pressing real-world problem, leverages the clique structure of MAGSs in a principled way, and addresses time continuity explicitly. The simulation scale is realistic, the comparison against Gurobi and HEAD is informative, and the reported performance figures are concrete and falsifiable. The main weakness is that the central problem transformation from P1 to P2 is not soundly established as written, and the reported sub-1% LF results depend on this transformation.

major comments (3)
  1. [Section III, Eq. (6)-(7)] The edge-construction rule in Eq. (6) uses S_I^s(c_s,t), the set of satellites already transmitting on subchannel c_s. This set is only defined after a subchannel assignment is chosen, so the edge set E(t) depends on the very coloring being optimized. Consequently f_con in Eq. (8) counts conflicts on a coloring-dependent graph, and P2 is not a standard K-coloring problem as stated. Please redefine the graph using potential co-channel interferers independent of the current assignment (e.g., all satellites above the horizon whose interference would exceed the threshold if co-channel), or provide a fixed-point/iterative formulation in which the graph and coloring are consistent. This is a load-bearing issue because all later algorithms operate on G(t).
  2. [Section III and Section VI-B] The claimed equivalence between P1 and P2 is not established. Fig. 9 is a threshold sweep of I_Gamma^th for CTS; it does not compare a P2-optimal coloring with a P1-optimal coloring on the same instances. No theorem bounds f_LF by f_con. Proposition 1 assumes the ITU constraint is met and concerns capacity degradation, not the P1-P2 gap. Please provide either a formal bound relating f_LF to f_con or a systematic numerical comparison (e.g., evaluating f_LF of colorings that minimize f_con on the same instances where Gurobi solves P1 directly).
  3. [Section III, Eq. (7)] Equation (7) is not well-posed as printed: the summation range and the role of I_s^th are ambiguous, and the expression appears to define a threshold from a sum over a subset of co-channel interferers that depends on the unknown coloring. Since I_s^th determines which edges are inserted into G(t), please rewrite this equation with explicit quantifiers and a clear definition of the set over which the sum is taken.
minor comments (5)
  1. [Section IV-B and Fig. 4] There are several typos: 'Freqency' in Section I-B, 'Adapitve' in Fig. 4, 'sturcture' in Section IV-B, and 'decompositon' in Section IV-D.
  2. [Algorithm 1] Algorithm 1 line 5 uses argmin over colors not used by neighbors; if all C colors are used by neighbors, the feasible set is empty, and the algorithm does not specify what color is assigned. The text in Section VI mentions a random color for conflicts, but the algorithm pseudocode should state this explicitly.
  3. [Section V-A, Eq. (26)] The notation log_{C/N}_s(1+I_R^th) is unusual; please write the base explicitly, e.g., log_{(C/N)_s}(1+I_R^th), to avoid confusion.
  4. [Section VI-A] The parameter p_s in Eq. (17) is used to control the long-term FSR but its value is not reported in Table I or the simulation setup. Please provide the value used in the simulations.
  5. [Eq. (32)] In the FSR formula, the outer sum is over all satellites S while m_c(s,t) is nonzero only for satellites selected in both t-1 and t; please clarify the index set.

Circularity Check

1 steps flagged · score 8.0 of 10

Eq. (6) defines the interference graph via S_I^s(c_s,t), the co-channel set of the very coloring P2 is optimizing, making the P1-to-P2 transformation self-referential.

  1. self definitional [Section III, Eqs. (6)-(9)]
    "edges are constructed according to the following rule: e_{u,s}(t) = (1, ∀s∈W(t), ∀u∈S_I^s(c_s,t), I_{u,s,t}≥I_s^th, 0, otherwise), (6) where the adaptive interference threshold I_s^th for satellite s is determined as the maximum value satisfying ... (7). On this basis, the number of conflicting edges for subchannel assignment scheme (coloring scheme) c is calculated by fcon(c,t) = Σ_{s∈W(t)} Σ_{u∈W(t)} e_{u,s}(t) δ(c_s−c_u), (8) then P1 is transformed into P2: min_c fcon(c,t). (9)"

    Earlier in Section II.A, S_I^u(c_u,t) is defined as the set of satellites 'simultaneously communicating on subchannel c_u', i.e., the set is determined by the current frequency allocation. Substituting that set into Eq. (6) makes the edge e_{u,s}(t) exist only when u is already assigned the same subchannel as s, and Eq. (7) makes the threshold I_s^th depend on the same assignment-dependent set. Therefore the graph G(t), the threshold, and the P2 objective fcon(c,t) are all functions of the candidate coloring c that P2 is supposed to determine. P2 is not a fixed-input K-coloring reformulation of P1; it is a self-referential count of strong co-channel pairs under c.

full rationale

The algorithmic contributions are otherwise self-contained: GG, CTS, TCFA-GG/CTS, and VSU are tested against external baselines (Global, HEAD, Gurobi) on a Starlink simulation, and no load-bearing self-citation or imported uniqueness theorem appears. The circularity is concentrated in the problem transformation. As written, Eq. (6) builds E(t) from S_I^s(c_s,t), the set of satellites already using subchannel c_s assigned to s; Eq. (7) tunes I_s^th from the same assignment-dependent set; and Eqs. (8)-(9) define P2 by minimizing conflicts on that self-referential graph. If the authors intended E(t) to represent potential co-channel interference independent of the current coloring, that would remove the circularity, but that is not what Eqs. (6)-(7) state. The later claim that 'the gap between P1 and P2 is trivial' (Section VI.B.1, Fig. 9) is an empirical threshold sweep for CTS and does not repair the definitional issue. Because the central derivation from P1 to P2 is self-referential by construction, the circularity score is 8.

Assumptions & free parameters 6 free parameters · 4 assumptions · 0 invented entities

The central claim depends on tuned parameters (I_Γ^th, algorithm hyperparameters, p_s) and on the assumption that the interference graph can be constructed independent of the allocation. The clique structure and P1-P2 equivalence are also assumed or fitted rather than derived.

free parameters (6)
  • I_Γ^th = -13 dB
    Weak interference threshold for graph construction; tuned offline via simulation (Fig. 9) to near the ITU threshold. Directly controls edge density and the claimed P1-P2 equivalence.
  • N_GG = 100
    Number of independent optimizations in GG; chosen by the authors as a computational budget, not derived.
  • N_t_in, N_t_ca, Nit, Nn = 2000, 500, 250, 10
    CTS hyperparameters for initial solutions, candidate selection, tabu iterations, and neighbors per iteration.
  • σ (Gaussian noise std) = not specified
    Perturbation added to degrees in GG stage 1 (Eq. 10); no value is given, affecting coloring order diversity.
  • p_s (FSR proportionality constant) = not specified
    Constant in Eq. (17) that controls probability of switching constrained vertices; value is not reported, yet it determines the achieved FSR.
  • C (number of subchannels) = N_at
    Set equal to number of antennas per MAGS, claimed as optimal balance between accessibility and capacity (Fig. 10).
assumptions (4)
  • ad hoc to paper The set S_I^s(c_s,t) of co-channel interferers can be used to build the graph before solving for c_s.
    Eq (6) uses S_I^s(c_s,t), which depends on the unknown allocation; this is a circular premise unless reinterpreted as potential interference.
  • domain assumption Each MAGS's selected satellites form a clique or quasi-clique of size N_at, and removing a few edges does not change the chromatic number.
    Used in Lemma 1 and CTS design; observed in simulation but not proved for all geometries.
  • ad hoc to paper The gap between P1 (minimize link failures) and P2 (minimize conflicting edges) is trivial when I_Γ^th is tuned near -13 dB.
    Asserted from Fig. 9; the equivalence is not derived, so the transformation's optimality rests on a fitted threshold.
  • domain assumption Satellite selection follows the maximum elevation angle principle and all satellites transmit at maximum power.
    Section II system model; influences the interference graph and clique structure, and represents a worst-case assumption.

how reviews work

0 comments
Cite this review

Pith. "Pith review of Time-Continuous Frequency Allocation for Feeder Links of Mega Constellations with Multi-Antenna Gateway Stations." pith.science (2026). https://pith.science/paper/UGEJI6YE

@misc{pith2026250512429,
  author       = {Pith},
  title        = {Pith review of: Time-Continuous Frequency Allocation for Feeder Links of Mega Constellations with Multi-Antenna Gateway Stations},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/UGEJI6YE}},
  note         = {Machine review of arXiv:2505.12429}
}
abstract

With the recent rapid advancement of mega low earth orbit (LEO) satellite constellations, multi-antenna gateway station (MAGS) has emerged as a key enabler to support extremely high system capacity via massive feeder links. However, the densification of both space and ground segment leads to reduced spatial separation between links, posing unprecedented challenges of interference exacerbation. This paper investigates graph coloring-based frequency allocation methods for interference mitigation (IM) of mega LEO systems. We first reveal the characteristics of MAGS interference pattern and formulate the IM problem into a $K$-coloring problem using an adaptive threshold method. Then we propose two tailored graph coloring algorithms, namely Generalized Global (GG) and Clique-Based Tabu Search (CTS), to solve this problem. GG employs a low-complexity greedy conflict avoidance strategy, while CTS leverages the unique clique structure brought by MAGSs to enhance IM performance. Subsequently, we innovatively modify them to achieve time-continuous frequency allocation, which is crucial to ensure the stability of feeder links. Moreover, we further devise two mega constellation decomposition methods to alleviate the complexity burden of satellite operators. Finally, we propose a list coloring-based vacant subchannel utilization method to further improve spectrum efficiency and system capacity. Simulation results on Starlink constellation of the first and second generations with 34396 satellites demonstrate the effectiveness and superiority of the proposed methodology.

Figures

Figures reproduced from arXiv: 2505.12429 by the authors.

Figure 1
Figure 1. Interference scenario of a SatCom system with mega constellation and [PITH_FULL_IMAGE:figures/full_fig_p002_1.png] view at source ↗
Figure 2
Figure 2. Interference comparison of MAGSs and SAGSs. [PITH_FULL_IMAGE:figures/full_fig_p003_2.png] view at source ↗
Figure 3
Figure 3. Aggregate I/N distributions under different [PITH_FULL_IMAGE:figures/full_fig_p004_3.png] view at source ↗
Figures from the paper (7 more)
Figure 4
Figure 4. Figure 4: Adapitve edge construction of satellite s2 and s4 on interference graph G(t), in which each satellite has its own adaptive threshold. If an edge exists between two vertices, they should use different colors to avoid conflict, i.e., their corresponding satellites should…
Figure 5
Figure 5. Figure 5: Illustration of Lemma 1, solution structure (13) and neighboring [PITH_FULL_IMAGE:figures/full_fig_p006_5.png]
Figure 6
Figure 6. Figure 6: An Example of GC with low FSR. Due to the dynamic nature of LEO [PITH_FULL_IMAGE:figures/full_fig_p007_6.png]
Figure 7
Figure 7. Figure 7: Link failure rate performance. (a) Time distributions of LF rate for different IM methods, [PITH_FULL_IMAGE:figures/full_fig_p010_7.png]
Figure 8
Figure 8. Figure 8: Visualization of subchannel allocation results obtained by GC-based IM. [PITH_FULL_IMAGE:figures/full_fig_p010_8.png]
Figure 10
Figure 10. Figure 10: LF rate versus C. 0.5 1 1.5 2 2.5 Link Failure Rate (1e-2) 0 100 200 300 400 500 600 700 Number of Time Slots [PITH_FULL_IMAGE:figures/full_fig_p011_10.png]
Figure 12
Figure 12. Figure 12: Performance of CCD and GSCD for CTS. 10-4 10-3 10-2 10-1 100 0 100 200 300 400 500 600 700 Number of Time Slots [PITH_FULL_IMAGE:figures/full_fig_p012_12.png]

Discussion (0). Continue with ORCID to comment.

Reference graph

Works this paper leans on

53 extracted references · 52 canonical work pages

  1. [1]

    On the road to 6G: Visions, requirements, key technologies, and testbeds,

    C.-X. Wang et al. , “On the road to 6G: Visions, requirements, key technologies, and testbeds,” IEEE Commun. Surv. Tutor., vol. 25, no. 2, pp. 905–974, Feb. 2023

  2. [2]

    Integrated satellite-terrestrial networks toward 6G: Architectures, applications, and challenges,

    X. Zhu and C. Jiang, “Integrated satellite-terrestrial networks toward 6G: Architectures, applications, and challenges,” IEEE Internet Things J., vol. 9, pp. 437–461, Nov. 2022

  3. [3]

    Satellite communications in the new space era: A survey and future challenges,

    O. Kodheli et al. , “Satellite communications in the new space era: A survey and future challenges,”IEEE Commun. Surv. Tutor., vol. 23, no. 1, pp. 70–109, Sep. 2020

  4. [4]

    A survey on nongeostationary satellite systems: The communication perspective,

    H. Al-Hraishawi et al., “A survey on nongeostationary satellite systems: The communication perspective,” IEEE Commun. Surv. Tutor., vol. 25, no. 1, pp. 101–132, Aug. 2023

  5. [5]

    A technical comparison of three low earth orbit satellite constellation systems to provide global broadband,

    I. Del Portillo, B. G. Cameron, and E. F. Crawley, “A technical comparison of three low earth orbit satellite constellation systems to provide global broadband,” Acta Astronautica , vol. 159, pp. 123–135, Jun. 2019

  6. [6]

    Ground segment architec- tures for large LEO constellations with feeder links in EHF-bands,

    I. del Portillo, B. Cameron, and E. Crawley, “Ground segment architec- tures for large LEO constellations with feeder links in EHF-bands,” in Proc. IEEE Aerosp. Conf. , Mar. 2018, pp. 1–14

  7. [7]

    Gateway station geographical planning for emerging non-geostationary satellites constellations,

    V . M. Baeza, F. Ortiz, E. Lagunas, T. S. Abdu, and S. Chatzinotas, “Gateway station geographical planning for emerging non-geostationary satellites constellations,” IEEE Network, Oct. 2023

  8. [8]

    Applications for Ka-band gateway earth station authorizations,

    SpaceX Services, Inc., “Applications for Ka-band gateway earth station authorizations,” IBFS File Nos. SES-LIC-20190816-01062 and 01063; SES-LIC-20190827-01110; SES-LIC-20190906-01170 and 01171, Nov. 2019

Show all 53 references
  1. [9]

    Application for fixed satellite service by spacex services,

    Federal Communications Commission (FCC), “Application for fixed satellite service by spacex services,” [Online]. Available: https://fcc. report/IBFS/Filing-List/SES-LIC, Jun. 2023. 13

  2. [10]

    Should we worry about interference in emerging dense NGSO satellite constellations?

    C. Braun, A. M. V oicu, L. Simi ´c, and P. M ¨ah¨onen, “Should we worry about interference in emerging dense NGSO satellite constellations?” in Proc. IEEE Int. Symp. Dynamic Spectr. Access Net. (DySPAN) , 2019, pp. 1–10

  3. [11]

    The dense sky: Evaluating system coexistence of new NGSO satellite constellations in the Ka band,

    J. Suilmann, A. M. V oicu, L. Simi ´c, and P. M ¨ah¨onen, “The dense sky: Evaluating system coexistence of new NGSO satellite constellations in the Ka band,” in Proc. IEEE Globecom Workshops (GC Wkshps) , 2021, pp. 1–6

  4. [12]

    Dynamic cooperative spectrum sharing in a multi-beam LEO-GEO co-existing satellite system,

    P. Gu, R. Li, C. Hua, and R. Tafazolli, “Dynamic cooperative spectrum sharing in a multi-beam LEO-GEO co-existing satellite system,” IEEE Trans. Wireless Commun., vol. 21, no. 2, pp. 1170–1182, Aug. 2021

  5. [13]

    Multi-satellite beam hopping based on load balancing and interference avoidance for NGSO satellite communication systems,

    Z. Lin, Z. Ni, L. Kuang, C. Jiang, and Z. Huang, “Multi-satellite beam hopping based on load balancing and interference avoidance for NGSO satellite communication systems,” IEEE Trans. Commun., vol. 71, no. 1, pp. 282–295, 2022

  6. [14]

    The next generation of beam hopping satellite systems: Dynamic beam illumination with selective precoding,

    L. Chen, V . N. Ha, E. Lagunas, L. Wu, S. Chatzinotas, and B. Ottersten, “The next generation of beam hopping satellite systems: Dynamic beam illumination with selective precoding,” IEEE Trans. Wireless Commun., vol. 22, no. 4, pp. 2666–2682, Oct. 2022

  7. [15]

    Satellite-terrestrial coordinated multi-satellite beam hopping scheduling based on multi- agent deep reinforcement learning,

    Z. Lin, Z. Ni, L. Kuang, C. Jiang, and Z. Huang, “Satellite-terrestrial coordinated multi-satellite beam hopping scheduling based on multi- agent deep reinforcement learning,” IEEE Trans. Wireless Commun. , vol. 23, no. 8, pp. 10 091–10 103, Feb. 2024

  8. [16]

    Newspace spectrum sharing: Assessing interference risk and mitigations for new satellite constellations,

    S. Tonkin and J. P. De Vries, “Newspace spectrum sharing: Assessing interference risk and mitigations for new satellite constellations,” in Proc. TPRC 46th Res. Conf. Commun. Inf. Internet Policy , Sep. 2018, pp. 1–102

  9. [17]

    Beam pointing optimization based downlink interference mitigation technique between NGSO satellite systems,

    L. Yin, R. Yang, Y . Yang, L. Deng, and S. Li, “Beam pointing optimization based downlink interference mitigation technique between NGSO satellite systems,” IEEE Wireless Commun. Lett., vol. 10, no. 11, pp. 2388–2392, Jul. 2021

  10. [18]

    Radio resource allocation for multi- antenna gateway stations of diverse NGSO constellation networks,

    Z. Ren, W. Li, J. Jin, and Y . Zhan, “Radio resource allocation for multi- antenna gateway stations of diverse NGSO constellation networks,” IET Commun., vol. 16, no. 7, pp. 734–744, Jan. 2022

  11. [19]

    Joint power and tilt control in satellite constellation for NGSO-GSO interference mitigation,

    M. Jalali, F. Ortiz, E. Lagunas, S. Kisseleff, L. Emiliani, and S. Chatzino- tas, “Joint power and tilt control in satellite constellation for NGSO-GSO interference mitigation,” IEEE Open J. Veh. Technol. , vol. 4, pp. 545– 557, Aug. 2023

  12. [20]

    Statistical CSI-based distributed precoding design for OFDM-cooperative multi-satellite systems,

    Y . Wang, V . N. Ha, K. Ntontin, H. Yan, W. Wang, S. Chatzinotas, and B. Ottersten, “Statistical CSI-based distributed precoding design for OFDM-cooperative multi-satellite systems,” 2025. [Online]. Available: https://arxiv.org/abs/2505.08038

  13. [21]

    Distributed beamforming for multiple LEO satellites with imperfect delay and doppler compensations: Modeling and rate analysis,

    S. Wu, Y . Wang, G. Sun, W. Wang, J. Wang, and B. Ottersten, “Distributed beamforming for multiple LEO satellites with imperfect delay and doppler compensations: Modeling and rate analysis,” IEEE Trans. Veh. Technol., May. 2025, Early Access

  14. [22]

    A risk assessment framework for NGSO-NGSO interference,

    F. T. A. Council, S. Group et al. , “A risk assessment framework for NGSO-NGSO interference,” Federal Communications Commision, Tech. Rep., Dec, 2017

  15. [23]

    Frequency prediction and assignment among SatComs networks: A CNN-LSTM approach,

    Z. Ren, J. Jin, W. Li, R. Wen, and Y . Zhan, “Frequency prediction and assignment among SatComs networks: A CNN-LSTM approach,” in Proc. 2022 IEEE/CIC Int. Conf. Commun. China , Aug. 2022, pp. 106–111

  16. [24]

    Frequency plan design for multibeam satellite constellations using integer linear programming,

    J. J. Garau-Luis, S. A. Torrens, G. C. Vila, N. Pachler, E. F. Crawley, and B. G. Cameron, “Frequency plan design for multibeam satellite constellations using integer linear programming,” IEEE Trans. Wireless Commun., vol. 23, no. 4, pp. 3312–3327, Aug. 2023

  17. [25]

    Avoiding self- interference in megaconstellations through cooperative satellite routing and frequency assignment,

    N. Pachler, E. F. Crawley, and B. G. Cameron, “Avoiding self- interference in megaconstellations through cooperative satellite routing and frequency assignment,” IEEE J. Sel. Areas Commun., vol. 42, no. 11, pp. 3188–3203, Jul. 2024

  18. [26]

    Frequency assignment: Theory and applications,

    W. Hale, “Frequency assignment: Theory and applications,” Proc. IEEE, vol. 68, no. 12, pp. 1497–1514, Dec. 1980

  19. [27]

    Low-cost mmwave MIMO multi- streaming via bi-clustering, graph coloring, and hybrid beamforming,

    A. Ghasemi and S. A. Zekavat, “Low-cost mmwave MIMO multi- streaming via bi-clustering, graph coloring, and hybrid beamforming,” IEEE Trans. Wireless Commun. , vol. 20, no. 7, pp. 4113–4127, Feb. 2021

  20. [28]

    Topological interference manage- ment with adversarial topology perturbation: An algorithmic perspec- tive,

    Y .-C. Liang, C.-S. Liao, and X. Yi, “Topological interference manage- ment with adversarial topology perturbation: An algorithmic perspec- tive,” IEEE Trans. Commun., vol. 70, no. 12, pp. 8153–8166, Oct. 2022

  21. [29]

    2-layer interference coordination framework based on graph coloring algorithm for a cellular system with distributed MU-MIMO,

    C. Ge, S. Xia, Q. Chen, and F. Adachi, “2-layer interference coordination framework based on graph coloring algorithm for a cellular system with distributed MU-MIMO,” IEEE Trans. Veh. Technol., vol. 72, no. 3, pp. 3557–3568, Nov. 2022

  22. [30]

    UA V-assisted emergency communications in social IoT: A dynamic hypergraph col- oring approach,

    B. Wang, Y . Sun, Z. Sun, L. D. Nguyen, and T. Q. Duong, “UA V-assisted emergency communications in social IoT: A dynamic hypergraph col- oring approach,” IEEE Internet Things J. , vol. 7, no. 8, pp. 7663–7677, Apr. 2020

  23. [31]

    A greedy approach combined with graph coloring for non-uniform beam layouts under antenna constraints in multibeam satellite systems,

    J.-T. Camino, S. Mourgues, C. Artigues, and L. Houssin, “A greedy approach combined with graph coloring for non-uniform beam layouts under antenna constraints in multibeam satellite systems,” in Proc. 2014 Adv. Satell. Multimed. Syst. Conf. Signal Process. Space , Sep. 2014, p...

  24. [32]

    Quantum annealing for complex optimization in satellite communication systems,

    T. Q. Dinh, S. H. Dau, E. Lagunas, S. Chatzinotas, D. N. Nguyen, and D. T. Hoang, “Quantum annealing for complex optimization in satellite communication systems,” IEEE Internet Things J. , vol. 12, no. 4, pp. 3771–3784, Oct. 2024

  25. [33]

    Recommendation ITU-R S.1528: Satellite antenna radiation patterns for non-geostationary orbit satellite antennas operating in the fixed-satellite service below 30 GHz,

    ITU-R, “Recommendation ITU-R S.1528: Satellite antenna radiation patterns for non-geostationary orbit satellite antennas operating in the fixed-satellite service below 30 GHz,” [Online]. Available: https://www. itu.int/rec/R-REC-S.1528, 2001

  26. [34]

    Available: https://www.itu.int/dms pubrec/itu-r/rec/s/ R-REC-S.1428-1-200102-I!!PDF-E.pdf, 2001

    ITU-R, “Recommendation ITU-R S.1428: Reference FSS earth-station radiation patterns for use in interference assessment involving non- GSO satellites in frequency bands between 10.7 GHz and 30 GHz,” [Online]. Available: https://www.itu.int/dms pubrec/itu-r/rec/s/ R-REC-S.1428-1...

  27. [35]

    ITU-R, “Recommendation ITU-R S.1325: Simulation methodologies for determining statistics of short-term interference between co-frequency, codirectional non-geostationary-satellite orbit fixed-satellite service sys- tems in circular orbits and other non-geostationary fixed-sate...

  28. [36]

    Co-frequency interference analysis and avoidance between NGSO constellations: Challenges, techniques, and trends,

    Y . He, Y . Li, and H. Yin, “Co-frequency interference analysis and avoidance between NGSO constellations: Challenges, techniques, and trends,” China Commun., vol. 20, no. 7, pp. 1–14, Jul. 2023

  29. [37]

    ITU-R, “Recommendation ITU-R S.1432: Apportionment of the allow- able error performance degradations to fixed-satellite service (FSS) hy- pothetical reference digital paths arising from time invariant interference for systems operating below 30 GHz,” 2006

  30. [38]

    Analysis of co-frequency interference avoidance effect of downlink between giant ngso constellations based on mesinr satellite selection,

    Y . Li and Y . He, “Analysis of co-frequency interference avoidance effect of downlink between giant ngso constellations based on mesinr satellite selection,” in Proc. 2023 Int. Conf. Commun. Technol. (ICCT) , Oct. 2023, pp. 1214–1218

  31. [39]

    Reducibility among combinatorial problems,

    R. M. Karp, “Reducibility among combinatorial problems,” Complexity of Computer Computations , pp. 85–103, 1972

  32. [40]

    Graph coloring based pilot assignment for cell-free massive MIMO systems,

    H. Liu, J. Zhang, S. Jin, and B. Ai, “Graph coloring based pilot assignment for cell-free massive MIMO systems,” IEEE Trans. Veh. Technol., vol. 69, no. 8, pp. 9180–9184, Jun. 2020

  33. [41]

    An upper bound for the chromatic number of a graph and its application to timetabling problems,

    D. J. Welsh and M. B. Powell, “An upper bound for the chromatic number of a graph and its application to timetabling problems,” Comput. J., vol. 10, no. 1, pp. 85–86, Jan. 1967

  34. [42]

    Effective and efficient dynamic graph coloring,

    L. Yuan, L. Qin, X. Lin, L. Chang, and W. Zhang, “Effective and efficient dynamic graph coloring,” in Proc. VLDB Endow. , vol. 11, no. 3, Nov. 2017, pp. 338–351

  35. [43]

    Complexity of clique coloring and related problems,

    D. Marx, “Complexity of clique coloring and related problems,” Theo- retical Computer Science , vol. 412, no. 29, pp. 3487–3500, Jul. 2011

  36. [44]

    Using tabu search techniques for graph coloring,

    A. Hertz and D. d. Werra, “Using tabu search techniques for graph coloring,” Computing, vol. 39, no. 4, pp. 345–351, May. 1987

  37. [45]

    The new memetic algorithm for graph coloring: An easy way for managing diversity,

    L. Moalic and A. Gondran, “The new memetic algorithm for graph coloring: An easy way for managing diversity,” in Proc. Eur. Conf. Evol. Comput. Comb. Optim. , Jan. 2015, pp. 173–183

  38. [46]

    Cluster analysis of multivariate data: efficiency versus interpretability of classifications,

    E. W. Forgy, “Cluster analysis of multivariate data: efficiency versus interpretability of classifications,” Biometrics, vol. 21, no. 3, pp. 761– 777, Sep. 1965

  39. [47]

    Graph colorings with local constraints-a survey,

    Z. Tuza, “Graph colorings with local constraints-a survey,” Discuss. Math. Graph Theory , vol. 17, no. 2, pp. 161–228, Sep. 1997

  40. [48]

    Amendment to pending applica- tion for the SpaceX Gen2 NGSO satellite system,

    Space Exploration Holdings, LLC, “Amendment to pending applica- tion for the SpaceX Gen2 NGSO satellite system,” File No. SA- TAMD2021081800105, Aug. 2021

  41. [49]

    Supplemental infor- mation regarding earth stations,

    Space Exploration Technologies Corp. (SpaceX), “Supplemental infor- mation regarding earth stations,” 2021

  42. [50]

    SpaceX non-geostationary satellite system,

    FCC, “SpaceX non-geostationary satellite system,” [Online]. Available: https://fcc.report/IBFS/SAT-MOD-20181108-00083/1569860.pdf, 2018

  43. [51]

    Gurobi Optimizer Reference Manual, Gurobi Optimization, LLC, Beaverton, OR, USA, 2022

  44. [52]

    Spectrum graph coloring and applications to Wi-Fi channel assignment,

    D. Orden, J. M. Gimenez-Guzman, I. Marsa-Maestre, and E. De la Hoz, “Spectrum graph coloring and applications to Wi-Fi channel assignment,” Symmetry, vol. 10, no. 3, p. 65, Mar. 2018

  45. [53]

    Study on handover techniques for satellite-to-ground links in high and low interference regimes,

    A. Bhattacharya and M. Petrova, “Study on handover techniques for satellite-to-ground links in high and low interference regimes,” in Proc. Jt. European Conf. Networks Commun. 6G Summit , Jun. 2023, pp. 359– 364

Pith tools

Reviewed August 15, 2026 · model on record in the stance chip above.