A Method for Recovery and Relative Positioning of Small UAVs

UAVs have garnered considerable attention due to their stealth, survivability, and the elimination of human casualties. Beyond traditional reconnaissance and attack, they have expanded into early warning, command, and electronic warfare. Particularly, small UAVs, equipped with lightweight precision instruments, transitions from standalone operations to sophisticated manned-unmanned teaming and swarm network configurations, further broadening their application horizons. However, the escalating costs associated with these advancements underscore the importance of efficient and reliable recovery methods. Recognizing the challenges posed by reduced navigation accuracy during UAVs’ recovery, especially within complex environments for swarms, we introduce an innovative radio positioning method, which harnesses signal transmissions among nodes to achieve relative positioning, thereby facilitating safe recovery. Addressing conventional positioning techniques often struggle to meet requirements at low ranging accuracies, we delved into the realm of cooperative positioning and proposed a novel TDOA-Chan method. Through theoretical derivation and simulations, we demonstrate that cooperative positioning among nodes can markedly enhance positioning accuracy, even under conditions of limited TDOA ranging precision. Our work not only shows the potential of cooperative positioning, but also paves the way for future endeavors aimed at optimizing UAV control.