Understanding and control of the magnetic sensitivity of a fiber-optic gyroscope

A good understanding of FOG (fiber-optic gyroscope) magnetic sensitivity is one of the key factors for making high-grade inertial navigation systems. With a typical sensitivity of 1°/h/gauss, very good magnetic shielding has become essential. The state of the art is to use multiple layers of μ-metal. As the shielding efficiency grows, the remaining magnetic sensitivity keeps decreasing, so it becomes difficult to measure it quickly and accurately. This paper describes an innovative method for the fast measurement of a high-efficiency magnetic shielding, using FOG technology.