A gyroscopic sensor unit detects a phase drift between a demodulated output signal and demodulation signal during output of a quadrature test signal. A delay calculator detects the phase drift based on changes in the demodulated output signal during application of the quadrature test signal. A delay compensation circuit compensates for the phase drift by delaying the demodulation signal by the phase drift value.

A gyroscopic sensor unit detects a phase drift between a demodulated output signal and demodulation signal during output of a quadrature test signal. A delay calculator detects the phase drift based on changes in the demodulated output signal during application of the quadrature test signal. A delay compensation circuit compensates for the phase drift by delaying the demodulation signal by the phase drift value.

The general field of the invention is that of passive resonator gyros comprising an injection laser emitting an initial optical beam at a first frequency and a fiber optic cavity. The gyro according to the invention operates with three optical beams at three different optical frequencies. A first beam is injected in a first direction of rotation, the second and the third beam are injected in the contrary direction. The gyro includes three slaving devices maintaining each optical frequency at a specific mode of resonance of the cavity. The gyro includes means for measuring the frequency differences existing between the different frequencies. Combined together, these differences are representative of the length of the cavity and the angular rotational velocity of the cavity along an axis perpendicular to its plane.

A fiber-optic measurement device (10) includes a SAGNAC ring interferometer (20) having a proper frequency f.sub.p, a detector (14) and a modulation chain (30) generating a phase-shift modulation φ.sub.m(t) between the two counter-propagating waves (24, 25) propagating in the ring interferometer. The device aims to reduce measurement faults due to the linearity defects in the modulation chain of such a measurement device with optical fiber. For this reason, the fiber-optic measurement device reduces the amplitude of the phase-shift modulation φ.sub.m(t) which is the sum of a first biasing phase-shift modulation component φ.sub.b1(t) and a first counter-reaction phase-shift modulation component φ.sub.cr1(t), the phase-shift modulation φ.sub.m(t) falling or rising by twice the amplitude of the first biasing phase-shift modulation component φ.sub.b1(t). A rate gyro including such a measurement device and an inertial stabilization or navigation unit including at least one such rate gyro are also described.

A novel and useful electronic gyroscope exploits the Sagnac resulting in a detectable phase or frequency shift when an electromagnetic wave travels inside a rotating medium. These shifts in phase or frequency are measured and used to determine the angular velocity of the rotating medium. Three such media can be positioned in mutually perpendicular planes to detect 3D rotational movement. At least one loop acts as an RF transmission media that accommodates simultaneous bidirectional propagation of RF signals while being capable of separating between signals counter propagating in two opposite directions through the use of a switching matrix. A switching matrix and loop buffer function to sample pulses, amplify them, and reinject them back into one of the loops. A time measurement unit functions to detect the time difference between the counter propagating pulses which is used to calculate the rotation rate of the loop.

A disk resonator is pumped by counterpropagating pump signals to produce corresponding counterpropagating Brillouin laser signals. The pump laser optical frequencies are separated by a frequency offset Δν.sub.P but excite the same nominal resonator optical mode; the Brillouin laser optical frequencies are separated by a beat frequency Δν.sub.L with 0<Δν.sub.L<Δν.sub.P. A photodetector receives the Brillouin laser signals and produces an electrical signal at the beat frequency Δν.sub.L. The frequency offset Δν.sub.P can be large so enough to prevent locking of the Brillouin laser signals onto a common Brillouin laser frequency. A signal processing system derives from the beat frequency Δν.sub.L an estimated angular velocity component of the disk optical resonator about an axis substantially perpendicular to the disk optical resonator.

Disclosed are systems and methods that utilize multicore optical fibers for gyro coil winding. Particularly, the use of multicore fiber enables inherent thermal stability without the need for complex, tedious, and costly winding patterns. Enabling the use of level winding techniques eliminates the need for complex quadrupole winding patterns. This simplicity lends itself to advancements towards full automation of winding coils for multicore fibers, without sacrificing performance. This, in turn increases the production rate and overcomes current barriers to fiber optic gyroscope (FOG) market expansion. In accordance with the embodiments, multicore fiber can be utilized in various gyro coil winding techniques, including: level winding; Interrupted Level Wind (ILW); and Dual Axis Symmetric (DAS) winding. Furthermore, each of the multicore fiber gyro coil winding patterns can incorporate a multicore shuffle bridge. The multicore shuffle bridge is designed to provide multiple features, such as facilitating the rotation of mating cores.

A gyroscopic sensor unit detects a phase drift between a demodulated output signal and demodulation signal during output of a quadrature test signal. A delay calculator detects the phase drift based on changes in the demodulated output signal during application of the quadrature test signal. A delay compensation circuit compensates for the phase drift by delaying the demodulation signal by the phase drift value.

Disclosed herein are systems and methods that utilize multicore optical fibers for gyro coil winding. Particularly, the use of multicore fiber enables inherent thermal stability without the need for complex, tedious, and costly winding patterns. Enabling the use of level winding techniques eliminates the need for complex quadrupole winding patterns. This simplicity lends itself to advancements towards full automation of winding coils for multicore fibers, without sacrificing performance. This, in turn increases the production rate and overcomes current barriers to fiber optic gyroscope (FOG) market expansion. In accordance with the embodiments, multicore fiber can be utilized in various gyro coil winding techniques, including: level winding; Interrupted Level Wind (ILW); and Dual Axis Symmetric (DAS) winding. Furthermore, each of the multicore fiber gyro coil winding patterns can incorporate a multicore shuffle bridge. The multicore shuffle bridge is designed to provide multiple features, such as facilitating the rotation of mating cores.

One example includes fiber optic gyroscope (FOG) assembly. The FOG assembly includes a spool comprising a flange. The FOG assembly also includes an optical fiber comprising an optical fiber coil portion that is counter-wound in a first orientation and a second orientation opposite the first orientation. The optical fiber portion can be coupled to the flange. The optical fiber further includes a loopback portion with respect to the first orientation that is secured to the flange.