Varanasi: In a major breakthrough, the Indian Institute of Technology (BHU), Varanasi, has developed a system that allows the sharing of images and messages without internet connectivity and with virtually infinite range.The innovation, which combines custom-built devices with drone-based relays, offers a new direction in resilient, long-range communication.Led by Hari Prabhat Gupta, associate professor at the department of computer science and engineering, the research team has created a dedicated self-sustaining transmission mechanism (SSTM) that uses autonomous drones to carry and forward data across large distances — even in areas without any communication infrastructure.The technique enables real-time sharing of images and text, allowing communication to continue in remote, obstructed, or high-interference regions. The system was tested in challenging conditions simulating signal-blocked environments and inaccessible zones.According to Gupta, the drones form a dynamic mesh network capable of adapting to terrain and movement, making it ideal for use in defence applications, border surveillance, territorial field communication, and disaster response.

"The system doesn't rely on conventional internet or satellite links," he said, adding, "It's an entirely new class of resilient communication where even blackhole-like zones can be bridged.

" The project focuses on three key areas: developing lightweight and energy-efficient communication devices, designing adaptive drone movement strategies, and building a mobile app to decode and display messages.The result is a scalable, low-cost, and intelligent communication system with potential uses in national security, emergency rescue operations, and off-grid mission-critical scenarios.The research is partially supported by TII-UAE, IDAPT-Hub Foundation at IIT (BHU), and SERB, and the team aims to expand the system for broader use in smart infrastructure, underground and rugged terrain communication, and future space-to-earth applications. The next phase includes integrating AI for autonomous drone path optimisation and encryption layers for secure transmissions.IIT-BHU director Prof Amit Patra congratulated the team members on successfully completing this research. The institute provided both financial and infrastructural support for the in-house development. It is also extending support for the next milestone, which involves converting the existing multi-story infrastructure into a LoRaWAN-enabled system.