On the construction of effective DRONEWALLS: Technologies and challenges for Counter-UAV systems

The proliferation of unmanned aerial vehicles (UAVs) has exposed various security/safety vulnerabilities in our infrastructure systems. The increased use of drones for military purposes, especially in the ongoing conflict between Russia and Ukraine, together with geopolitical tensions, further exacerbate the situation. In September 2025, the European Union has called for a “drone wall” initiative to build up a robust Counter-UAV (C-UAV) system along the east flank of Europe. Existing research on C-UAV often remains fragmented, with detection, analysis, and neutralization studied in isolation or reviews covering a limited number of papers in community-specific outlets only. Our study introduces the so-called DRONEWALLS framework, a unified approach structured in three phases: Detection (radio frequency/spectrum sensing, radar/LiDAR, optical/thermal imaging, and acoustic/vibration-based), analysis/decision-making (weighted sensor fusion, edge AI/real-time processing, and simulation/benchmarking), as well as action/compliance (neutralization, legal/ethical adherence, and litigation). By synthesizing over 400 studies, nearly three times as many as in existing reviews, we provide an accurate depiction of the state of the art on C-UAV systems and their technological challenges, including systemic integration and adaptive, scalable solutions tailored to both civilian and strategic security needs.