What Are Zero Offset And Zero Drift?

Zero offset is the output of the gyroscope when the input angular velocity is zero (that is, the gyroscope is at rest). It is expressed by the equivalent input angular velocity corresponding to the average value of the output measured in the specified time, and ideally is the component of the angular velocity of the earth’s rotation.Zero drift is zero offset stability, which represents the degree of dispersion of gyroscope output around its zero offset mean value when the input angular rate is zero, and is represented by the equivalent input angular rate corresponding to the standard deviation of the output in the specified time.Zero drift is the most important and basic index to measure the precision of FOG.The main cause of zero drift is the non-reciprocal phase shift error introduced in the fiber coil by the change of ambient temperature distribution along the fiber.Usually in order to stabilize zero drift, often need to IFOG temperature control or temperature compensation.In addition, polarization will also have a certain impact on zero drift. Polarization filtering and polarization-maintaining optical fiber are often used to eliminate the influence of polarization on zero drift in IFOG.