Breakthrough in High‑precision Underground Positioning and Navigation Technology Led by CETC

According to China Electronics Technology Group Corporation, a major original advance in ultra‑wide‑band positioning has been achieved after national technical acceptance organised by the Ministry of Science and Technology. This research project was spearheaded by the State Key Laboratory of Integrated Spatio‑Temporal Networks and Equipment under CETC Network and Communications Research Institute. It addresses the technical bottlenecks for long‑distance, large‑capacity, high‑precision autonomous positioning and unmanned navigation control within vast underground spaces.

Satellite‑based navigation cannot function underground. Navigation signals fail to penetrate thick rock, concrete and metallic frameworks. Underground tunnels are narrow with heavy structural shielding, while metal machinery and airborne dust further disrupt radio signals and create harsh electromagnetic surroundings.

The research team put forward an innovative digital‑twin channel‑modelling approach combining real‑time online data gathering with offline model optimisation. “It is like drawing an accurate portrait for radio signals, breaking the limits of conventional statistical modelling,” a laboratory official stated. The core of this solution lies in generating wireless environmental maps for large underground spaces. These maps visualise signal power, time delay and propagation direction, and characterise non‑stationary behaviour of ultra‑wide‑band radio waves amid complicated underground structures. Reliable channel modelling has resolved the fundamental problem whereby underground radio signals could not be clearly interpreted or accurately calculated.

The team has also established a flexible spatio‑temporal information networking framework. The network can scale smoothly from a single base‑station unit up to city‑wide deployment. On‑site testing shows the system supports 69,894 positioning nodes in total, with over 23,675 concurrent positioning targets. Such capacity satisfies high‑concurrency positioning demands across varied underground scenarios.

Scalable hybrid positioning‑navigation and control systems have been deployed at two extra‑large coal mines, Menkeqing and Dahaize. For the first time domestically, continuous above‑and‑below‑ground positioning relying on a mining‑grade smartphone with the single Beidou solution has been realised. Practical trials have delivered comprehensive upgrades for underground mine positioning: shifting from one‑dimensional tracking to three‑dimensional locating, from flat two‑dimensional mapping to three‑dimensional digital twinning, extending Beidou coverage down below ground, and enabling precise autonomous navigation for underground driverless vehicles. The technical results will deliver core support for intelligent transformation within China’s coal‑mining sector.