摘要 |
A method and circuit arrangement for determining angular velocities with the aid of an optical fiber ring interferometer includes filter circuitry for selecting the amplitudes of four adjacent spectral lines of resultant interfering light waves exiting from the interferometer, a first adder for adding amplitudes of spectral lines at the lowest and second highest frequency, a second adder for adding spectral line amplitudes at the second lowest and the highest frequency, a divider for forming a quotient by dividing a first product of the first adder's sum and the amplitude at the second highest frequency by a second product of the second adder's sum and the second lowest frequency amplitude if the second lowest frequency is an even numbered harmonic of the modulation frequency, and by dividing the second product by the first product if the second lowest frequency is an odd numbered haromonic of the modulation frequency; a first circuit device for weighting the quotient with a ratio of the ordinal of the harmonic which coincides with the second highest spectral line frequency to the harmonic which coincides with the second lowest spectral line frequency if the second lowest spectral line frequency is an even numbered harmonic of the modulation frequency, and with an inverse of the factor if the second lowest spectral line frequency is an odd numbered harmonic of the modulation frequency; and a second circuit device for using the arc tangent function on the square root of the weighted quotient to determine the Sagnac phase.
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