Recent technological advances have brought to the end-user market smartphones that are able to remain fully-functional even when submerged under water. This capability will soon enable the commercialization of a plethora of exciting smartphone apps, including life-saving systems such as real-time monitoring of scuba divers breathing. On the other hand, it becomes paramount to empower smartphones with end-to-end underwater communication capabilities.

Technology Overview

iSonar the first system implementing reliable software-defined acoustic networking between water-proof smartphones and the first system implementing end-to-end software-defined networking between amphibious smartphones.   

The iSonar system transforms off-the-shelf smartphones into ultrasonic software “radios” that implement an orthogonal frequency division multiplexing-based communication system. iSonar achieves reliable transmission by implementing a fully-software-defined network stack that guarantees end-to-end reliable underwater communication by sending and receiving information through the AUX interface of smartphones. The system uses commercially available acoustic transducers, along with oscillators, switches, to transform the RF wave generated by the  smartphone into an acoustic wave that is then transmitted underwater. 

Nu Researchers have implemented a fully-functional hardware/software prototype of iSonar on Android smartphones and off-the-shelf electronic equipment, and extensively evaluated its performance through several experiments in a tank testbed. Results show that iSonar is able to achieve packet error rate (PER) of 10-3, which is significant considering the low audio sampling rate and the strong multipath effect induced by the water tank environment. 


  • Uses the AUX interface of smartphones

  • Fully-software-defined network protocol stack

  • End-to-end underwater acoustic communication

  • Works with off-the-shelf smartphones

  • Requires limited additional hardware 


  • Texting, sending pictures/video while underwater

  • Crowdsourced monitoring of marine wildlife

  • Discovery of people in distress (e.g., drowning) 

Patent Information:
For Information, Contact:
Dormant Computer
Northeastern University
Francesco Restuccia
Emrecan Demirors
Tommaso Melodia