FIELD: fiber optics, design of fiber-optical gyroscopes and other fiber transducers of physical quantities based on ring fiber-optical interferometer. SUBSTANCE: invention is aimed at reduction of influence of spurious modulation of intensity of beams of ring interferometer on stability of scale factor of fiber- optical gyroscope when beams pass through channel waveguides of integral-optical phase modulator and at rise of sensitivity of gyroscope. Difference of phases of ring interferometer is formed in the form of pulse sequence of four levels of auxiliary phase modulation. Error signal of change of levels of phase modulation is extracted. Optimum levels of phase modulation are selected. EFFECT: reduction of influence of spurious modulation on stability of scale factor, risen sensitivity of gyroscope. 5 dwg
