A Fiber-Based Sensing Array for Persistent Ocean Monitoring

Undersea applications involving acoustic propagation often require continual knowledge of the sound speed at different depths. Existing systems that collect sound velocity profile data have a limited lifetime. To address this need, we are developing long-length, fiber sensing arrays that can persistently monitor water characteristics. Here, we describe the process used to fabricate these fibers, as well as a custom technique for integrating electronics into the fiber. An application specific integrated circuit (ASIC) was designed and fabricated for handling long-distance communication along the fiber. A proof-of-concept demonstration was performed in the ocean where temperature was measured for 3 hours and compared to a reference temperature probe. The fiber sensing array presented here offers a lightweight, low-power system for persistent monitoring of the ocean.