Fiber Optic Averaging Magnetometer for Submarines (FOAMS)

Physical Sciences Inc. (PSI) proposes development of a Fiber Optic Averaging Magnetometer for Submarines (FOAMS) sensor to support the Circuit-D system that monitors and maintains low magnetic field signatures on Virginia-class submarines. Presently, arrays of fluxgate magnetometers serve as on-board magnetic field monitors, but these discrete sensors are influenced by local magnetic inhomogeneities caused by welds, bulkheads, and support beams that do not represent the average hull magnetization. The FOAMS sensor will provide the spatial average of the axial and two transverse vector components of the magnetic field along a long, thin sensor element. The optical-based sensor element will contain only passive components to reduce sensitivity to electromagnetic interference and enable scaling from 2-100 m lengths. The proposed design will achieve comparable performance to fluxgate magnetometers while overcoming the susceptibility of discrete sensors to local magnetic inhomogeneity.