Fiber optic gyro system applications on strapdown attitude control

The drift specification for high bandwidth/low noise gyros applicable to attitude control systems is determined by the order of earth rate drift, which is up to + or - 15 deg/hr depending on orientation with the earth rate vector. Attention is presently given to a phase-modulated fiber-optic gyro meeting these specifications, with 10 deg/hr drift (by comparison with the 0.01 deg/hr drift of mechanical gyros). Noise is noted to impose no limit on the use of such a broad bandwidth.