Multichannel fiber-optic magnetometer system for undersea measurements

• Published in: Journal of lightwave technology Vol. 13; no. 7; pp. 1385 - 1395
• Main Authors: Bucholtz, F., Villarruel, C.A., Davis, A.R., Kirkendall, C.K., Dagenais, D.M., McVicker, J.A., Patrick, S.S., Koo, K.P., Gunnar Wang, Valo, H., Lund, T., Andersen, A.G., Gjessing, R., Eidem, E.J., Knudsen, T.
• Format: Journal Article
• Language: English
• Published: IEEE 01-07-1995
• Subjects: Geomagnetism; Magnetic noise; Magnetic variables measurement; Magnetometers; Magnetostriction; Optical design; Optical interferometry; Optical noise; Phase noise; Transducers
• ISSN: 0733-8724; 1558-2213
• DOI: 10.1109/50.400703

We have designed, fabricated, and operated an undersea array of eight fiber-optic vector magnetometers. Each magnetometer consists of three magnetostrictive transducers aligned on orthogonal axes and incorporated in a single Michelson interferometer. During undersea operation, each interferometer exhibited less than 1 /spl mu/rad//spl radic/ Hz phase noise, and the self-noise of each magnetic transducer was less than 0.2 nT//spl radic/ Hz at 0.1 Hz. We discuss the design and performance of the optical system including noise mechanisms. We present the results of magnetic measurements of the geomagnetic field and the magnetic tracking of ships.< >