RSSI-Based Autonomous Tracking System for Radio-Tagged Flying Insects Using UAV With Rotational Antenna

The escalating effects of climate change have heightened the urgency of ecosystem conservation efforts worldwide. In this context, pollinators such as honeybees play a critical role in maintaining ecosystem health. However, they face appreciable threats, including the proliferation of invasive alien species (IAS) and colony collapse disorder. In this study, we propose a novel tracking system that uses unmanned aerial vehicles (UAVs) equipped with rotational directional antennas and radio telemetry systems. This approach, which represents an improvement over our previous works, aims to protect biodiversity and ecosystem resilience by mitigating the adverse impacts of IAS on pollinator populations. To implement the proposed tracking strategy, a motor-based directional antenna that can rotate 360° is attached to a UAV, and the received signal strength indicator (RSSI) value is used to localize the hornets to which sensors are attached. The proposed tracking system was verified in a simulated field environment that was constructed by considering the RSSI values obtained in a forest. In addition, the robustness and field applicability of the tracking system were improved by applying it to scenarios consisting of different paths that were constructed considering the dynamic nature of hornets.