Hybrid positioning system improves tracking where GPS falls short

Researchers have developed a hybrid positioning system designed to maintain accurate location tracking in environments where GPS signals are weak or unavailable. The technology targets locations such as tunnels, dense urban areas, and underground infrastructure, where satellite navigation often struggles.

The system, called Joint DAS and GNSS (JDG), combines GPS with Distributed Acoustic Sensing (DAS). DAS turns existing fiber-optic cables into highly sensitive vibration sensors by detecting tiny changes in light signals caused by movement near the cable.

In field tests conducted in southern England, researchers collected both GPS data and vibration data from a fiber-optic cable while participants traveled along a test route. An AI model fused the two data sources, allowing it to continue estimating participants’ positions even when GPS signals were temporarily lost or significantly degraded.

According to the research team, the hybrid approach outperformed GPS-only positioning systems. It also remained effective when location updates were collected less frequently, suggesting it could be suitable for battery-powered devices such as smartphones and Internet of Things (IoT) sensors.

The researchers believe the technology could benefit applications including smart transportation, emergency response, and autonomous vehicles. By combining satellite navigation with fiber-optic sensing, the system could provide more reliable positioning in urban environments and other areas where GPS coverage is limited.