Researchers develop mobile all-light network for seamless air land and underwater connectivity

Researchers develop mobile all-light network for seamless air land and underwater connectivity
by Simon Mansfield
Sydney, Australia (SPX) Dec 11, 2024

Researchers from Nanjing University of Posts and Telecommunications have introduced a groundbreaking prototype for an all-light mobile communication network. This system facilitates seamless data exchange across air, land, and underwater environments, even when communication nodes are mounted on moving vehicles. The innovation has potential applications in navigation, emergency responses, research, and commercial sectors.

"Our all-light wireless network combines different light sources to ensure uninterrupted connectivity while also dynamically aligning optical paths between moving nodes," said Yongwin Wang, the research team leader. "This enables two-way real-time data transmission, ensuring reliable communication and data exchange within and across networks, regardless of the environment."

Published in Optics Express by the Optica Publishing Group, the study demonstrates that two prototypes mounted on separate moving vehicles can achieve bidirectional light transmission, successfully linking nodes across air and underwater domains.

"Our new wireless optical communication system could enable continuous connectivity for essential mobile nodes like drones, vehicles, and ships," added Wang. "This could transform the way mobile networks operate."

Tackling Alignment Challenges

The project builds on earlier fixed-node communication experiments. This iteration resolves the critical challenge of dynamic optical path alignment, enabling full-duplex communication for mobile nodes. "We also provide a new network architecture that ensures even and accurate comprehensive connectivity across all its parts while simultaneously supporting fast, two-way data exchange," explained Wang.

The system integrates multiple optical communication methods: green light for TCP/IP operations, blue laser communication for underwater vehicles, deep ultraviolet communication to avoid solar interference, and 850-nm laser diode systems for receiving data. All components are linked via Ethernet switches, connecting terminals such as sensors and personal computers.

Dynamic optical alignment is achieved with an image identification module and a full-duplex communication module mounted on a three-axis gimbal stabilizer. The module captures real-time images of light signals, enabling the system to maintain alignment automatically. This ensures seamless bidirectional data flow under the TCP/IP protocol without delays or data loss.

Successful Air-Water Demonstration

The researchers conducted outdoor and indoor tests using two green-light devices installed on separate moving vehicles. Experiments demonstrated smooth bidirectional light transmission across air and underwater environments with a maximum bandwidth of 4 Mbps, sufficient for transmitting video and audio. The system also provided internet access through a Wi-Fi modem and delivered stable video communication between the two environments.

Future plans aim to integrate wired and wireless nodes with diverse light sources and incorporate technologies like radio, sonar, and gas communication to develop a comprehensive network. "In the future, we could combine on-chip light communication with free-space light communication to create an all-light interconnection communication network," Wang said. "Such sophisticated all-light networks could enable advanced information processing and computing systems."

Research Report:Mobile all-light communication network