Orientation Matters: Learning Radiation Patterns of Multi-Rotor UAVs In-Flight to Enhance Communication Availability Modeling
Pith reviewed 2026-05-13 19:58 UTC · model grok-4.3
The pith
Radiation patterns of two heterogeneous UAVs can be learned and decoupled from joint calibration flight data using linear regression.
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
By flying both UAVs together along a joint trajectory in an open area, received signal strength measurements can be used to fit independent sets of polynomial coefficients for each vehicle's radiation pattern. The resulting models, expressed either through spherical harmonic expansions or weighted sums over inducing points, reconstruct the directional gain of each antenna separately.
What carries the argument
Joint calibration trajectory combined with linear regression on polynomial coefficients that decouples the two UAV radiation patterns modeled as spherical harmonics series or weighted averages over inducing samples.
If this is right
- Enables rapid recalibration of models when payloads or antenna configurations change on either UAV.
- Supports more accurate autonomous path planning that accounts for orientation effects on link quality.
- Improves swarm control algorithms in settings where UAV setups are modified between missions.
- Maintains communication availability predictions without separate calibration flights or dedicated test equipment.
Where Pith is reading between the lines
- The regression approach could extend to three or more UAVs by increasing the number of coefficient sets solved simultaneously.
- Adding terms for known obstacles or multipath effects might allow the same decoupling in non-anechoic environments.
- The technique could apply to learning orientation-dependent performance of other onboard systems such as cameras or sensors.
Load-bearing premise
A single joint calibration trajectory in an obstacle-free anechoic altitude supplies enough measurements to separate the two UAVs' radiation patterns through linear regression of their polynomial coefficients.
What would settle it
After learning the patterns from the calibration data, collect signal strength measurements on independent flights and check whether the prediction error remains at or below the original 3.6 dB noise level.
Figures
read the original abstract
The paper presents an approach for learning antenna Radiation Patterns (RPs) of a pair of heterogeneous quadrotor Uncrewed Aerial Vehicles (UAVs) by calibration flight data. RPs are modeled either as a Spherical Harmonics series or as a weighted average over inducing samples. Linear regression of polynomial coefficients simultaneously decouples the two independent UAVs' RPs. A joint calibration trajectory exploits available flight time in an obstacle-free anechoic altitude. Evaluation on a real-world dataset demonstrates the feasibility of learning both radiation patterns, achieving 3.6 dB RMS error, the measurement noise level. The proposed RP learning and decoupling can be exploited in rapid recalibration upon payload changes, thereby enabling precise autonomous path planning and swarm control in real-world applications where setup changes are expected.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The paper claims that radiation patterns (RPs) of two heterogeneous quadrotor UAVs can be learned and decoupled from joint in-flight calibration measurements using linear regression on spherical-harmonics or inducing-point coefficients. A single obstacle-free anechoic-altitude trajectory is used to collect received-power data; the resulting model achieves 3.6 dB RMS error on real-world data, stated to equal the measurement noise floor. The learned RPs are positioned as enabling improved communication availability modeling for path planning and swarm control after payload changes.
Significance. If the decoupling result is robust, the work would provide a practical, data-driven route to accurate per-UAV antenna models without separate anechoic-chamber campaigns. Reaching noise-limited error on real flights is a concrete strength that directly supports downstream uses in autonomous UAV communication planning.
major comments (2)
- [Methods / Regression formulation] The central decoupling step (linear regression of the joint coefficient vector) is load-bearing for the claim that both RPs are recovered independently. No rank, condition-number, or singular-value analysis of the design matrix formed from the two UAVs' basis functions along the chosen trajectory is reported; limited relative yaw or insufficient angular diversity could render the matrix rank-deficient, making the recovered patterns non-unique even when RMS error appears low.
- [Experimental evaluation] The evaluation reports 3.6 dB RMS error matching measurement noise, yet provides no description of data-exclusion criteria, train/validation/test splits, or propagation of measurement uncertainty into the fitted coefficients. Without these, it is impossible to judge whether the noise-limited result generalizes or is an artifact of the particular trajectory and preprocessing.
minor comments (2)
- [Notation / Model] Notation for the two UAVs' coefficient vectors and the combined design matrix should be introduced with explicit dimensions and a short matrix-equation example to clarify how the simultaneous regression is constructed.
- [Abstract] The phrase 'anechoic altitude' in the abstract is unclear; clarify whether an open-sky outdoor site or a controlled chamber is intended.
Simulated Author's Rebuttal
We thank the referee for the constructive feedback on our manuscript. We provide point-by-point responses to the major comments below.
read point-by-point responses
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Referee: [Methods / Regression formulation] The central decoupling step (linear regression of the joint coefficient vector) is load-bearing for the claim that both RPs are recovered independently. No rank, condition-number, or singular-value analysis of the design matrix formed from the two UAVs' basis functions along the chosen trajectory is reported; limited relative yaw or insufficient angular diversity could render the matrix rank-deficient, making the recovered patterns non-unique even when RMS error appears low.
Authors: We agree that an explicit analysis of the design matrix is necessary to confirm that the decoupling is unique. In the revised manuscript we will add the rank, condition number, and singular-value spectrum of the joint design matrix constructed from the two UAVs' basis functions evaluated along the calibration trajectory. This will be placed in the Methods section and will demonstrate that the matrix is full rank and numerically stable, thereby supporting the claim that both radiation patterns are independently recoverable. revision: yes
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Referee: [Experimental evaluation] The evaluation reports 3.6 dB RMS error matching measurement noise, yet provides no description of data-exclusion criteria, train/validation/test splits, or propagation of measurement uncertainty into the fitted coefficients. Without these, it is impossible to judge whether the noise-limited result generalizes or is an artifact of the particular trajectory and preprocessing.
Authors: We acknowledge that additional experimental details are required for reproducibility and to rule out artifacts. In the revised manuscript we will expand the Experimental Evaluation section to describe the data-exclusion criteria applied, the train/validation/test partitioning of the flight data, and the procedure used to propagate measurement uncertainty into the estimated coefficients. These additions will allow readers to assess whether the reported 3.6 dB RMS error is robust. revision: yes
Circularity Check
No significant circularity detected
full rationale
The paper fits radiation pattern coefficients for two UAVs via simultaneous linear regression on received-power measurements collected along a joint calibration trajectory, then reports RMS error on the real-world dataset as 3.6 dB matching the independently observed measurement noise floor. This evaluation step compares the residual directly to external noise statistics rather than to any quantity defined by the fitted coefficients themselves. No self-definitional loops, fitted-input predictions, or load-bearing self-citations appear in the derivation; the central claim remains independently falsifiable against the noise benchmark and does not reduce to its inputs by construction.
Axiom & Free-Parameter Ledger
free parameters (1)
- Spherical harmonics polynomial coefficients
axioms (1)
- domain assumption Antenna radiation patterns can be modeled as a Spherical Harmonics series or as a weighted average over inducing samples
Lean theorems connected to this paper
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IndisputableMonolith/Foundation/AlexanderDuality.leanalexander_duality_circle_linking unclear?
unclearRelation between the paper passage and the cited Recognition theorem.
Linear regression of polynomial coefficients simultaneously decouples the two independent UAVs' RPs... Spherical Harmonics (SH) model... G(α, β; p) = Σ p_{l,m} Y_{l,m}
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IndisputableMonolith/Cost/FunctionalEquation.leanwashburn_uniqueness_aczel unclear?
unclearRelation between the paper passage and the cited Recognition theorem.
RPs are modeled either as a Spherical Harmonics series or as a weighted average over inducing samples
What do these tags mean?
- matches
- The paper's claim is directly supported by a theorem in the formal canon.
- supports
- The theorem supports part of the paper's argument, but the paper may add assumptions or extra steps.
- extends
- The paper goes beyond the formal theorem; the theorem is a base layer rather than the whole result.
- uses
- The paper appears to rely on the theorem as machinery.
- contradicts
- The paper's claim conflicts with a theorem or certificate in the canon.
- unclear
- Pith found a possible connection, but the passage is too broad, indirect, or ambiguous to say the theorem truly supports the claim.
Reference graph
Works this paper leans on
-
[1]
Multi-robot online sensing strategies for the con- struction of communication maps,
A. Quattrini Li et al., “Multi-robot online sensing strategies for the con- struction of communication maps,”Autonomous Robots, vol. 44, no. 3-4, pp. 299–319, 2019.DOI:10.1007/s10514-019-09862-3
-
[2]
Advances in Measuring the Environmental and Social Impacts of Environmental Programs
A. Muralidharan and Y . Mostofi, “Communication-aware robotics: Exploiting motion for communication,”Ann. Rev. of Control, Robot., and Auton. Syst., vol. 4, no. 1, pp. 115–139, 2021.DOI:10.1146/annurev- control- 071420-080708
-
[3]
Communication-aware uav path planning,
A. Mardani, M. Chiaberge, and P. Giaccone, “Communication-aware uav path planning,”IEEE Access, vol. 7, pp. 52 609–52 621, 2019.DOI:10.1109/ access.2019.2911018
-
[4]
A critical review of communications in multi-robot systems,
J. Gielis, A. Shankar, and A. Prorok, “A critical review of communications in multi-robot systems,”Curr . Robot. Reports, vol. 3, no. 4, pp. 213–225, 2022.DOI:10.1007/s43154-022-00090-9
-
[5]
Fast swarming of uavs in gnss-denied feature-poor environments without explicit communication,
J. Horyna, V . Kr ´atk´y, V . Pritzl, T. B ´aˇca, E. Ferrante, and M. Saska, “Fast swarming of uavs in gnss-denied feature-poor environments without explicit communication,”IEEE Robot. and Autom. Lett., vol. 9, no. 6, pp. 5284–5291, 2024.DOI:10.1109/lra.2024.3390596
-
[6]
Mrs drone: A modular platform for real-world deployment of aerial multi-robot systems,
D. Hert et al., “Mrs drone: A modular platform for real-world deployment of aerial multi-robot systems,”J. Intell. & Robot. Syst., vol. 108, no. 4, 2023. DOI:10.1007/s10846-023-01879-2
-
[7]
Experimentally analyzing diverse antenna placements and orientations for uav communications,
M. Badi, J. Wensowitch, D. Rajan, and J. Camp, “Experimentally analyzing diverse antenna placements and orientations for uav communications,”IEEE Trans. V eh. Technol., vol. 69, no. 12, pp. 14 989–15 004, 2020.DOI:10 . 1109/tvt.2020.3031872
-
[8]
Accessing from the sky: A tutorial on uav communications for 5g and beyond,
Y . Zeng, Q. Wu, and R. Zhang, “Accessing from the sky: A tutorial on uav communications for 5g and beyond,”Proc. of the IEEE, vol. 107, no. 12, pp. 2327–2375, 2019.DOI:10.1109/jproc.2019.2952892
-
[9]
B. Hu and X. Dong, “Communications channel characteristics in the presence of aircraft body blockage in urban air mobility,”IEEE Trans. V eh. Technol., vol. 73, no. 7, pp. 10 703–10 707, 2024.DOI:10 . 1109 / tvt . 2024 . 3384375
work page 2024
-
[10]
Communication mapping for robot teams,
J. Diller, J. G. Rogers, N. T. Dantam, and Q. Han, “Communication mapping for robot teams,”IEEE Trans. Field Robot., vol. 2, pp. 288–307, 2025.DOI: 10.1109/tfr.2025.3568794
-
[11]
Impact of uav structure on antenna radiation patterns at different frequencies,
A. Rizwan, D. Biswas, and V . Ramachandra, “Impact of uav structure on antenna radiation patterns at different frequencies,” inProc. of Int. Conf. on Antenna Innovations & Modern Technologies for Ground, Aircraft and Satellite Applications (iAIM), IEEE, 2017, pp. 1–5.DOI:10.1109/iaim. 2017.8402597
-
[12]
M. Mahbub et al., “Uav-assisted wireless communications in the 6g-and- beyond era: An extensive survey on characteristics, standardization and reg- ulations, enabling technologies, challenges, and future directions,”V ehicular Communications, vol. 56, p. 100 977, 2025.DOI:10.1016/j.vehcom. 2025.100977
-
[13]
Energy- efficient fixed-wing uav relay with considerations of airframe shadowing,
D. Bonilla Licea, M. Bonilla E., M. Ghogho, and M. Saska, “Energy- efficient fixed-wing uav relay with considerations of airframe shadowing,” IEEE Commun. Lett., vol. 27, no. 6, pp. 1550–1554, 2023.DOI:10.1109/ lcomm.2023.3264780
-
[14]
Improving data collection efficiency of uav-assisted lora networks via directivity-aware link model,
J. Zhang, X. Zheng, R. Li, L. Liu, H. Ma, and N. Kato, “Improving data collection efficiency of uav-assisted lora networks via directivity-aware link model,”IEEE Trans. Netw., vol. 33, no. 5, pp. 2208–2223, 2025.DOI:10. 1109/ton.2025.3559889
-
[15]
A Survey of Optimization-Based Task and Motion Planning: From Classical to Learning Approaches
A. T. Koru, J. Chang, and Y . Wan, “Rssi-based distributed control to align directional antenna pairs for uav communication,”IEEE/ASME Trans. Mechatronics, vol. 29, no. 4, pp. 2877–2885, 2024.DOI:10.1109/tmech. 2024.3403911
-
[16]
In: 2023 International Conference on Unmanned Aircraft Systems, pp
D. B. Licea, G. Silano, M. Ghogho, and M. Saska, “Communications-aware robotics: Challenges and opportunities,” inProc. of Int. Conf. on Unmanned Aircraft Syst. (ICUAS), IEEE, 2023.DOI:10.1109/icuas57906.2023. 10155882
-
[17]
Modeling microwave propagation in natural caves using lidar and ray tracing,
M. D. Bedford, A. Hrovat, G. Kennedy, T. Javornik, and P. Foster, “Modeling microwave propagation in natural caves using lidar and ray tracing,”IEEE Trans. Antennas Propag., vol. 68, no. 5, pp. 3878–3888, 2020.DOI:10 . 1109/tap.2019.2957969
-
[18]
On the spatial predictability of communi- cation channels,
M. Malmirchegini and Y . Mostofi, “On the spatial predictability of communi- cation channels,”IEEE Trans. Wireless Commun., vol. 11, no. 3, pp. 964–978, 2012.DOI:10.1109/twc.2012.012712.101835
-
[19]
Machine learning for channel quality prediction: From concept to experimental validation,
Z. Becvar, J. Plachy, P. Mach, A. Nikolov, and D. Gesbert, “Machine learning for channel quality prediction: From concept to experimental validation,” IEEE Trans. Wireless Commun., vol. 23, no. 10, pp. 14 605–14 619, 2024. DOI:10.1109/twc.2024.3417532
-
[20]
A comprehensive survey on uav com- munication channel modeling,
C. Yan, L. Fu, J. Zhang, and J. Wang, “A comprehensive survey on uav com- munication channel modeling,”IEEE Access, vol. 7, pp. 107 769–107 792, 2019.DOI:10.1109/access.2019.2933173
-
[21]
Direction estimation in 3d outdoor air–air wireless channels through machine learning,
M. H. Syed, M. Singh, and J. Camp, “Direction estimation in 3d outdoor air–air wireless channels through machine learning,”Sensors, vol. 23, no. 23, p. 9524, 2023.DOI:10.3390/s23239524
-
[22]
B. Yang, T. Taleb, Y . Shen, X. Jiang, and W. Yang, “Performance, fairness, and tradeoff in uav swarm underlaid mmwave cellular networks with direc- tional antennas,”IEEE Trans. Wireless Commun., vol. 20, no. 4, pp. 2383– 2397, 2021.DOI:10.1109/twc.2020.3041800
-
[23]
X. Dai, B. Duo, X. Yuan, and M. D. Renzo, “Energy-efficient uav com- munications with directional antennas: Tilting effect modeling and trajectory optimization,”IEEE Trans. V eh. Technol., vol. 74, no. 7, pp. 11 194–11 206, 2025.DOI:10.1109/tvt.2025.3545454
-
[24]
D. B. Licea, H. El Hammouti, G. Silano, and M. Saska, “Harnessing the potential of omnidirectional multi-rotor aerial vehicles in cooperative jamming against eavesdropping,” inProc. of Global Communications Con- ference (GLOBECOM), IEEE, 2024, pp. 2052–2058.DOI:10 . 1109 / globecom52923.2024.10901802
-
[25]
D. B. Licea, G. Silano, M. Ghogho, and M. Saska, “Omnidirectional multi- rotor aerial vehicle pose optimization: A novel approach to physical layer security,” inProc. of Int. Conf. on Acoustics, Speech and Sig. Proc. (ICASSP), IEEE, 2024, pp. 9021–9025.DOI:10 . 1109 / icassp48485 . 2024 . 10447876 Preprint version. Submitted to the IEEE for possible publication
work page 2024
-
[26]
Swarm intelligence-inspired au- tonomous flocking control in uav networks,
F. Dai, M. Chen, X. Wei, and H. Wang, “Swarm intelligence-inspired au- tonomous flocking control in uav networks,”IEEE Access, vol. 7, pp. 61 786– 61 796, 2019.DOI:10.1109/access.2019.2916004
-
[27]
Effect of antenna orientation on the air-to-air channel in arbitrary 3d space,
N. C. Matson, S. M. Hashir, S. Song, D. Rajan, and J. Camp, “Effect of antenna orientation on the air-to-air channel in arbitrary 3d space,” inProc. of Int. Symp. on a World of Wireless, Mobile and Multim. Netw. (WoWMoM), IEEE, 2021, pp. 298–303.DOI:10.1109/wowmom51794.2021.00055
-
[28]
A. Y . Umeyama, J. L. Salazar-Cerreno, and C. J. Fulton, “Uav-based far- field antenna pattern measurement method for polarimetric weather radars: Simulation and error analysis,”IEEE Access, vol. 8, pp. 191 124–191 137, 2020.DOI:10.1109/access.2020.3027790
-
[29]
G. Pupillo et al., “Medicina array demonstrator: Calibration and radiation pattern characterization using a uav-mounted radio-frequency source,”Ex- perimental Astronomy, vol. 39, no. 2, pp. 405–421, 2015.DOI:10.1007/ s10686-015-9456-z
work page 2015
-
[30]
S. Jan, Y . Liu, and C. D. Sarris, “Efficient neural network-based reconstruction of three-dimensional antenna radiation patterns from two-dimensional cuts,” IEEE Open J. Antennas Propag., vol. 6, no. 3, pp. 726–734, 2025.DOI: 10.1109/ojap.2025.3544968
-
[31]
New cosine-q pattern formulas for the analysis of elongated-aperture antennas,
J. Wang and Y . Rahmat-Samii, “New cosine-q pattern formulas for the analysis of elongated-aperture antennas,”IEEE Trans. Antennas Propag., vol. 72, no. 2, pp. 1893–1898, 2024.DOI:10.1109/tap.2023.3348573
-
[32]
E. K. Miller, “Adaptive sparse sampling to estimate radiation and scattering patterns to a specified uncertainty with model-based parameter estimation: Compute patterns using as few as two to four samples per lobe,”IEEE Antennas Propag. Mag., vol. 57, no. 4, pp. 103–113, 2015.DOI:10.1109/ map.2015.2453920
-
[33]
Impact of 3d uwb antenna radiation pattern on air-to-ground drone connectivity,
J. Chen, D. Raye, W. Khawaja, P. Sinha, and I. Guvenc, “Impact of 3d uwb antenna radiation pattern on air-to-ground drone connectivity,” inProc. of V ehicular Technology Conference (VTC-Fall), IEEE, 2018, pp. 1–5.DOI: 10.1109/vtcfall.2018.8690726
-
[34]
Analysis of antenna radiation patterns by means of spherical wavelets,
A. Quennelle, A. Chabory, P. Pouliguen, R. Contreres, and G. Le Fur, “Analysis of antenna radiation patterns by means of spherical wavelets,” in Proc. of European Conference on Antennas and Propagation (EuCAP), IEEE, 2022, pp. 1–5.DOI:10.23919/eucap53622.2022.9769478
-
[35]
Installed radiation pattern of patch antennas: Prediction based on a novel equivalent model,
S.-P. Gao, B. Wang, H. Zhao, W.-J. Zhao, and C. E. Png, “Installed radiation pattern of patch antennas: Prediction based on a novel equivalent model,” IEEE Antennas Propag. Mag., vol. 57, no. 3, pp. 81–94, 2015.DOI:10 . 1109/map.2015.2437275
-
[36]
When robotics meets wireless communications: An introductory tutorial,
D. Bonilla Licea, M. Ghogho, and M. Saska, “When robotics meets wireless communications: An introductory tutorial,”Proc. of the IEEE, vol. 112, no. 2, pp. 140–177, 2024.DOI:10.1109/jproc.2024.3380373
-
[37]
R. Allard and D. Werner, “The model-based parameter estimation of antenna radiation patterns using windowed interpolation and spherical harmonics,” IEEE Trans. Antennas Propag., vol. 51, no. 8, pp. 1891–1906, 2003.DOI: 10.1109/tap.2003.815419
-
[38]
M. Rahman, I. Guvenc, J. A. Abrahamson, A. Mishra, and A. Bhuyan, “Characterization of the combined effective radiation pattern of uav-mounted antennas and ground station,” 2025.DOI:10 . 48550 / ARXIV . 2506 . 01925
work page 2025
-
[39]
Px4: A node-based multithreaded open source robotics framework for deeply embedded platforms,
L. Meier, D. Honegger, and M. Pollefeys, “Px4: A node-based multithreaded open source robotics framework for deeply embedded platforms,” inProc. of Int. Conf. on Robotics and Automation (ICRA), IEEE, 2015, pp. 6235–6240. DOI:10.1109/icra.2015.7140074
-
[40]
T. Lee, M. Leok, and N. H. McClamroch, “Geometric tracking control of a quadrotor uav on se(3),” inProc. of Conference on Decision and Control (CDC), IEEE, 2010, pp. 5420–5425.DOI:10.1109/cdc.2010.5717652
-
[41]
Parametric modeling of radiation patterns and scattering parameters of antennas,
N. Mutonkole, E. R. Samuel, D. I. L. de Villiers, and T. Dhaene, “Parametric modeling of radiation patterns and scattering parameters of antennas,”IEEE Trans. Antennas Propag., vol. 64, no. 3, pp. 1023–1031, 2016.DOI:10 . 1109/tap.2016.2521883
-
[42]
Z. Zhang, P. Wang, Z. Ma, W. Hu, and M. He, “Uncertainty quantification of radiation pattern in radome-enclosed antennas via integrated gaussian process regression and grey wolf optimization,”IEEE Antennas Propag. Lett., vol. 24, no. 8, pp. 2587–2591, 2025.DOI:10.1109/lawp.2025.3569433
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