A pseudo-heterodyne fiber optical gyro, using integrated optics

A hybrid fiber-optical gyro using a novel scheme for pseudo-heterodyne detection is presented. The large bandwidth of integrated optical phase modulators allows for the use of a triangular-wave for dynamical biasing of the interferometer, while still being able to choose the modulation frequency to be the eigenfrequency of the fiber-loop. It is shown that this, together with the use of a dual-channel approach, minimizes both bias and scale factor errors. It is proposed that the fourth harmonic can be used to keep the modulation index of the applied triangular-wave phase modulation at the correct height and thus guarantee a good scale factor linearity.<
>