Electromagnetic Compatibility Study of Quadcopter UAVs: Characteristic Mode Analysis of the Frame's Material and Shape Effect

The variation in flight attitude, line-of-sight, and speed of unmanned aerial vehicles (UAVs) affect their polarization-dependent coupling cross-section and resultant compatibility to pulsed electromagnetic energy. Here, we present the out-of-band electromagnetic compatibility (EMC) effects of UAV frame material and shape on the UAV subcomponents. Characteristic mode analysis (CMA) is employed to study the fundamental modes supported by UAVs which facilitate the interpretation of its electromagnetic response and the prediction of its effect on the nearby components. Using CMA, we develop a framework that optimizes the placement of wires and traces of printed circuit boards (PCBs) on the frame mitigating interference from undesired electromagnetic sources. A 3-D scanner is used to provide four versions of a quadrotor UAV to study the frame shape effect on the coupling. Materials of differing permittivity are assigned to these frame versions to assist in understanding the material effect on the EM coupling to the UAV.