Patent ID: 8610995

Claim:
A method for modulating the phase of a pair of optical waves in a Sagnac interferometer, the method comprising: generating a phase modulation signal ( 701 ), where the phase modulation signal is the summation of phase modulation component signals including (i) a bias phase modulation component signal ( 705 ) having a selected bias modulation amplitude and waveform, (ii) a rotation-rate feedback phase modulation component signal ( 702 ), (iii) a waveform adjust component signal ( 706 ) for keeping the phase modulation within a predetermined range, and (iv) a calibration feedback phase modulation component signal ( 707 ), wherein said calibration feedback phase modulation component alternates back and forth between substantially constant values, a first substantially constant value and a second substantially constant value that is either 2π greater than the first substantially constant value or 2π less than the first substantially constant value, and the first substantially constant value is held for first time durations and the second substantially constant value is held for second time durations.