3D attitude control boosts maritime air to sea communication speeds
3D Euler-Angle Orientation Control for Two-Ray Fading Mitigation in Maritime Air-to-Sea Communications
Robotics
Summary
Maritime air-to-sea communication signals can weaken when two main signal paths—direct and sea-reflected—interfere destructively. The authors found that controlling the full three-dimensional orientation (attitude) of a drone’s antenna can reduce this interference by adjusting how the signals combine. They developed a method to calculate the best drone angles to improve signal strength and implemented a control system for the drone to maintain these angles during flight. This approach improved data throughput by over 11% compared to simpler angle adjustments.
What this means in practice
- •For drone communication engineers: Enhance UAV-based maritime communication links by adjusting drone orientation in three dimensions to reduce signal fading and increase throughput.
- •For maritime wireless system operators: Improve reliability and data rates of air-to-sea communication systems through orientation control of airborne nodes.
Authors
Mohammed Bajja, Abdoul Karim A. H. Saliah, Hajar El Hammouti, Daniel Bonilla Licea, Giuseppe Silano
Abstract
Maritime Air-to-Sea links are dominated by a line-of-sight ray and a sea-surface reflected ray whose destructive combination produces deep fades. Existing mitigation strategies optimize Unmanned Aerial Vehicle position or trajectory but leave attitude unexploited. This paper treats the full three dimensional attitude as a physical-layer control variable that shapes the two-ray interference through antenna phase-center displacement. Under small-angle and far-field assumptions, the constructive-interference condition reduces to an affine constraint in the Euler angles and admits a closed-form family of minimum-norm attitude candidates. A differentiable soft-minimum rule yields a smooth reference tracked by a constrained Nonlinear Model Predictive Control controller on a fully-actuated tilting multirotor. The proposed scheme increases cumulative throughput by 11.4% over a pitch-only benchmark and 22.2% over a zero-orientation baseline, while preserving trajectory tracking and respecting actuator limits.