Dynamic topology reconfiguration is central to the reliability and efficiency of large satellite constellations, yet many existing approaches rely on idealized assumptions such as full constellation deployment or uniform orbital spacing. We present Adaptive Satellite Topology via Regret-Aware learning (ASTRA), a theoretically-grounded framework for dynamic satellite topology reconfiguration that builds on an online learning formulation and makes it computationally practical. ASTRA combines an ADMM-based offline solver with efficient online updates for both online gradient descent and online conditional gradient, yielding markedly cheaper constrained updates than generic optimization pipelines. On the theory side, we show that for a relevant class of entry-wise nonzero utility matrices, the objective is strongly convex, which yields logarithmic static regret for online gradient descent, and we further instantiate known dynamic-regret guarantees under inexact ADMM inner loops. Empirically, ASTRA matches or improves topology quality, presenting a good trade-off with computational time on synthetic constellations, and it remains effective on real Starlink data under partial deployment and non-uniform spacing, where idealized structural assumptions break down. These results position ASTRA as an efficient and theoretically grounded approach to topology reconfiguration in realistic Low Earth Orbit networks.
Figures & tables
Metrics
E ↑
A-Deg ↑
CC ↓
A-SP ↓
Time (s) ↓
+Grid
130
3.94
1
4 .036
0.001
× Grid
124
3.76
1
4.978
0.001
DoTD
1 31
3 .97
1
4.412
0.023
Motif
132
4.00
1
4.292
1.326
GUTO
128
3.88
1
3.767
0.091
ASTRA
128
3.88
1
3.767
0.071
Table 1: Methods applied on Iridium-like constellation, with 6 orbital planes and 11 uniformly-spaced satellites per plane. ASTRA is capable of achieving the same results as GUTO in a fraction of the time, while closely matching with state-of-the-art performance.
Metrics
Method
Approximation
E ↑
A-Deg ↑
CC ↓
A-SP* ↓
+Grid
—
2869.14±14.123
3.608±0.017
9.038±2.019
—
× Grid
2468.77±19.325
3.205±0.026
3.346±1.314
—
DoTD
3183.16±0.586
3.998±0.001
4.211±1.436
—
GUTO
H
2900.95 ± 13.033
3.650 ± 0.015
1.233±0.491
15.742±0.388
ASTRA
2900.24±13.058
3.649±0.015
1.264 ± 0.533
15.760±0.381
Table 2: Comparison on Starlink data. Only GUTO and ASTRA attain runs with a single connected component; therefore, A-SP* is reported only for topologies satisfying this condition. ASTRA preserves the connectivity regime of GUTO while improving efficiency.
Algorithm:
+Grid
× Grid
DoTD
GUTO
ASTRA
Time (s)
0.021±0.001
0.026±0.001
3262.927±48.097
665.027±2.093
567.949±5.615
Table 3: Average time and respective std each method takes to propose a topology (Starlink), after 10 runs.+Grid and × Grid are the fastest methods.
Appendix figures & tables6 assets
Supplementary material from the paper’s appendix.
Appendix
Parameter:
Description:
λ
Weight given to the utilities being considered.
ρ
Penalty parameter from the Augmented Lagrangian.
ϵ
Stopping criteria value.
projits
Number of iterations for the Projected Gradient (Alg. 1 ) that deals with the update over the matrix X .
T
Maximum number of iterations of the ASTRA algorithm.
Λ
Weight to be given to the connections between satellites.
Appendix
Table 4: List of the parameters for the ASTRA offline algorithm.
Metrics
λ
Approximation
E ↑
A-Deg ↑
CC ↓
A-SP ↓
Time (s)
0
H
121
3.667
1
4.678
0.047
0.15
122
3.697
1
4.648
0.055
0.30
123
3.727
1
4.650
0.071
0.45
122
3.697
1
4.726
0.104
0.60
124
3.758
1
4.482
0.133
Appendix
Table 5: Effect of the parameter λ and the approximation of the FOV of a satellite on the results of the ADMM-based algorithm, for an Iridium-like constellation.
Metrics
ρ
Approximation
E ↑
A-Deg ↑
CC ↓
A-SP ↓
Time (s)
0.001
H
128
3.879
1
4.082
0.204
0.01
124
3.758
1
4.482
0.212
0.1
124
3.758
1
4.482
0.178
0.25
124
3.758
1
4.482
0.078
0.5
124
3.758
1
4.482
0.086
Appendix
Table 6: Effect of the parameter ρ and the approximation of the FOV of a satellite on the results of the ADMM-based algorithm, for an Iridium-like constellation.
Metrics
projits
E ↑
A-Deg ↑
CC ↓
A-SP ↓
Time (s)
5
124
3.758
1
4.556
0.075
10
124
3.758
1
4.556
0.108
20
124
3.758
1
4.556
0.207
30
124
3.758
1
4.556
0.323
40
124
3.758
1
4.556
0.412
Appendix
Table 7: Effect of the parameter projits on the results of the ADMM-based algorithm, for both synthetic and real data.
Metrics
Algorithm:
E ↑
A-Deg ↑
CC ↓
SP* ↓
#{¬P}↓
A- #{¬P}↓
GUTO
2898.71±13.993
3.647±0.017
1.129±0.335
15.668±0.372
0
0±0.0
ASTRA
2897.87±14.232
3.646±0.017
1.171±0.377
15.704±0.355
0
0±0.0
ASTRA-OGD
2746.68±19.604
3.456±0.024
1.855±0.728
14.303±0.431
6153
89.174±9.902
ASTRA-OCG
3169.20±2.511
3.984±0.003
1.029±0.168
11.103±0.473
15199
220.275±48.962
Appendix
Table 8: Graph metric comparison between offline and online algorithms for 70 consecutive Starlink topologies. In addition to graph metrics, we also consider the total number of connections that do not respect matrix P , “ #{¬P} ”, and its average value per topology “A- #{¬P} ”.
Number of iterations:
20K
30k
40k
Time (s)
330.870±3.462
430.103±0.983
658.597±3.747
Appendix
Table 9: Wall-clock time needed for ASTRA-OCG to achieve a certain number of iterations for a fixed topology. The mean values and respective std are presented for 10 runs.