A One-Way Acoustic Deep-Sea Navigation and Positioning System for Long-Range Autonomous Underwater Vehicles Groups

Accurate and robust underwater positioning is essential for enabling autonomous operations of underwater vehicles in deep-sea environments, particularly within the framework of the industrial underwater Internet of Things (IoT). Conventional acoustic positioning systems typically rely on two-way ranging, which doubles the signal travel distance, thereby reducing accuracy, increasing energy consumption, and constraining operational range. To address these limitations, this study presents a novel deep-sea navigation and positioning framework based on one-way acoustic communication synchronized via atomic clocks. This approach significantly shortens signal propagation paths and improves real-time responsiveness, enabling high-precision long-range operations. To enhance signal detection under low signal-to-noise ratio (SNR) conditions, a signal processing scheme is developed that integrates spread-spectrum modulation with energy-based normalization, effectively extending the operational range beyond 10 km. Sea trials conducted at depths greater than 4000 m validate the proposed system, achieving a maximum horizontal range of 11.5 km and an average positioning error of only 0.15% relative to the slant range. Furthermore, the system’s inherent scalability supports simultaneous positioning of multiple autonomous underwater vehicles (AUVs), paving the way for future large-scale, cooperative deep-sea exploration missions.