The Signal Processing Group (GTS) and the Photonics Research Lab (PRL) at the iTEAM Institute of the Universitat Politècnica de València (UPV) will participate in the upcoming edition of the International Conference on Optical Fiber Sensors (OFS), one of the most prestigious conferences in the field of optical fiber sensing, where they will present a groundbreaking advancement in underwater acoustics.
The study, titled “Directional Sensing of Underwater Acoustic Waves using a 7-core FBG Membrane Hydrophone,” introduces a novel hydrophone design based on multicore Fiber Bragg Gratings (FBGs), capable not only of detecting the presence of underwater acoustic waves but also of determining their direction within a plane perpendicular to the fiber. The device developed by GTS and PRL features a seven-core optical fiber adhered to the center of a latex membrane mounted on a 3D-printed cylindrical shell. During the experiments, acoustic waves in the range of 50 to 400 Hz were generated using an underwater speaker, and Bragg wavelength shifts were recorded using a high-speed spectrum analyzer.By applying advanced signal processing techniques, the team was able to experimentally validate the theoretical behavior of the sensor. The results revealed consistent signal patterns across the different fiber cores, allowing the bending direction to be determined with an angular precision of 64.09º relative to the reference axis.
This development marks a significant step toward the creation of underwater sensors capable of identifying the three-dimensional direction of acoustic sources, with potential applications in maritime surveillance, marine wildlife tracking, and underwater communications.