CN112710294B - Low-optical-noise double-ring parallel resonant gyro system and method - Google Patents
Low-optical-noise double-ring parallel resonant gyro system and method Download PDFInfo
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- G01C19/72—Gyrometers using the Sagnac effect, i.e. rotation-induced shifts between counter-rotating electromagnetic beams with counter-rotating light beams in a passive ring, e.g. fibre laser gyrometers
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Abstract
The application discloses a low-optical-noise double-ring parallel resonant fiber optic gyroscope system and a method, the system comprises a narrow-line-width tunable Laser, wherein light emitted by the Laser is divided into two paths of transmission, namely a counterclockwise path and a clockwise path, after passing through a multifunctional integrated phase modulator MIOC; after passing through the intensity modulator IM1, the counterclockwise light is split into two beams after passing through the 1 × 2 fiber Coupler1, wherein one beam is converted into an electrical signal by the photodetector PD 1; the other beam enters an annular cavity FRR1 formed by hollow photonic crystal fibers through a 2 x 2 fiber Coupler2, and then emergent light of the resonant cavity is converted into an electric signal by a photoelectric detector PD2 connected to Coupler 2; after passing through an intensity modulator IM2, light in a clockwise path is divided into two beams after passing through a 1 × 2 optical fiber Coupler3, and one beam is converted into an electric signal by a photoelectric detector PD 3; the other beam enters a ring cavity FRR2 formed by hollow photonic crystal fibers through a 2 x 2 fiber Coupler4, and emergent light of the resonant cavity is converted into an electric signal through a photoelectric detector PD4 connected to Coupler 4.
Description
Technical Field
The application relates to the technical field of fiber optic gyroscopes, in particular to a double-ring parallel resonant gyroscope system with low optical noise and a method thereof.
Background
The fiber optic gyroscope is an angular velocity sensor based on the Sagnac effect, and has the advantages of being fast in starting, high in reliability, easy to integrate and the like. The resonant fiber optic gyroscope is one of the resonant fiber optic gyroscopes, and the physical effect of the resonant fiber optic gyroscope is enhanced by utilizing the circulating propagation of a light path in a resonant cavity. Compared with an interference type fiber-optic gyroscope, the resonant fiber-optic gyroscope has the advantages that the required resonant cavity ring length is greatly shortened under the condition of meeting the same performance index, so that the resonant fiber-optic gyroscope has the potential of miniaturization and integration, and is concerned in recent years.
Although resonant fiber optic gyroscopes have many advantages, the practical application of fiber optic gyroscopes is still focused on interferometric fiber optic gyroscopes. This is because the resonant fiber optic gyroscope must use a narrow-line-width laser light source, and the strong coherence of the laser light source increases noise caused by backscattering, parasitic effects, and the like, thereby greatly limiting the practical use of the resonant fiber optic gyroscope. At present, back scattering, Kerr noise and polarization fluctuation are all important factors influencing the detection precision of the resonant fiber-optic gyroscope.
Disclosure of Invention
The embodiments of the present application provide a dual-ring parallel resonant gyroscope system with low optical noise and a method thereof, so as to solve the problem that the detection accuracy in the existing scheme of the resonant fiber-optic gyroscope is limited by backscattering, kerr noise and polarization fluctuation from the source.
According to a first aspect of the embodiments of the present application, a low optical noise dual-ring parallel resonant fiber optic gyroscope system is provided, which includes a narrow-linewidth tunable Laser, and light emitted by the Laser is divided into two paths of propagation, namely, a counterclockwise path and a clockwise path, after passing through a multi-function integrated phase modulator MIOC; after passing through the intensity modulator IM1, the light in the counterclockwise path is divided into two beams after passing through the 1 × 2 fiber Coupler1, wherein one beam is converted into an electrical signal by the photodetector PD 1; the other beam enters an annular cavity FRR1 formed by hollow photonic crystal fibers through a 2 x 2 fiber Coupler2, and then emergent light of the resonant cavity is converted into an electric signal by a photoelectric detector PD2 connected to Coupler 2; after passing through the intensity modulator IM2, the clockwise light is divided into two beams after passing through the 1 × 2 fiber Coupler3, and one beam is converted into an electrical signal by the photodetector PD 3; the other beam enters a ring cavity FRR2 formed by hollow photonic crystal fibers through a 2X 2 fiber Coupler4, and light emitted from the resonant cavity is converted into an electric signal through a photoelectric detector PD4 connected to a Coupler 4.
Furthermore, the multifunctional integrated phase modulator MIOC is a Y-type optical waveguide fabricated on a niobium lithiumate substrate by adopting a proton exchange technology.
Furthermore, a sinusoidal modulation voltage V ═ Msin (2 pi f) is applied across the multifunctional integrated phase modulator MIOC, and a sinusoidal signal is generated by the digital processing board, that is, the clockwise path and the counterclockwise path adopt the same modulation frequency f and modulation coefficient.
Further, the intensity modulator IM1, the photodetector PD1 and the digital processing board form a Power Feedback 1; the intensity modulator IM2, the photoelectric detector PD3 and the digital processing board form a Power Feedback2 of optical Power closed loop; the optical power closed loop feedback enables the optical power entering the resonant cavity in a clockwise way and a counterclockwise way to be the same and stable.
Further, the hollow photonic crystal fiber resonant cavities FRR1 and FRR2 are formed by the same polarization-maintaining type hollow photonic crystal fibers, have the same fiber length and the same fiber ring diameter, and are stacked in parallel.
Further, the intensity modulators IM1 and IM2 both have a polarization extinction ratio of 30dB or more, and all the beam splitters and couplers are single-axis polarization maintaining devices.
Further, all fiber solder joints are 0 ° fusion splices.
Further, output signals of the photoelectric detectors PD2 and PD4 are acquired and calculated by a digital processing board, and positive and negative phase-locked demodulation outputs are obtained.
Further, the Laser, the photodetector PD2 and the digital processing board form a frequency closed-loop Feedback frequency Feedback, so that the center frequency of the Laser is always locked at the resonant frequency of the counterclockwise resonant cavity.
According to a second aspect of the embodiments of the present application, there is provided a noise processing and signal detecting method for a resonant gyroscope, the method being implemented based on the dual-ring parallel resonant fiber optic gyroscope system with low optical noise according to the first aspect, the method including:
the method comprises the following steps: the PD1 detects the light intensity of the counterclockwise path and converts the light intensity into an electric signal, the Proportional Integral (PI) feedback quantity is calculated after the electric signal is collected by a digital processing board, the PI feedback quantity is converted into voltage change and is applied to a voltage modulation port of the IM1, and therefore the light power entering the resonant cavity from the counterclockwise path is controlled to be stabilized at a fixed target value I, and light power closed loop feedback1 is formed; the PD3 detects the light intensity of the clockwise path and converts the light intensity into an electric signal, the Proportional Integral (PI) feedback quantity is calculated after the electric signal is collected by a digital processing board and is converted into voltage change to be applied to a voltage modulation port of the IM2, so that the light power entering the resonant cavity of the clockwise path is controlled to be stabilized at a fixed target value I, and a light power closed loop feedback2 is formed;
step two: a sinusoidal modulation signal is applied to the MIOC, and the sinusoidal modulation signal is generated and converted into voltage by the digital processing board;
step three: the PD2 detects the light intensity output from the FRR1 and converts the light intensity into an electric signal, the electric signal is multiplied by a sine reference signal after being collected by a digital processing board, then the demodulation result of a counterclockwise path is obtained by filtering the signal by a low pass filter LPF1, the PD4 detects the light intensity output from the FRR2 and converts the light intensity into an electric signal, the electric signal is multiplied by another sine reference signal after being collected by a digital processing board, and then the demodulation result of a clockwise path is obtained by filtering the signal by a low pass filter LPF 2;
step four: the demodulation result of the counterclockwise path is processed by a digital processing board to calculate Proportional Integral (PI) feedback quantity, and the PI feedback quantity is converted into voltage change to be applied to a frequency modulation port of the laser, so that the central frequency of the laser is always locked on the resonant frequency of the counterclockwise path resonant cavity to form a frequency feedback closed loop; the demodulation result of the clockwise path is the output of the resonant fiber-optic gyroscope system.
The technical scheme provided by the embodiment of the application can have the following beneficial effects:
according to the embodiment, the design idea of 'single-ring two-way modulation' of the traditional resonant fiber gyroscope is broken through, two hollow photonic crystal fiber rings made of the same material are respectively used as resonant cavities of a clockwise path and a counterclockwise path, a multifunctional integrated phase modulator is used for conducting the same sine phase modulation on the two paths, in addition, a full polarization-maintaining optical path system scheme and an intensity modulator are added for controlling light intensity, and optical noise caused by back scattering, the Kerr effect and polarization state fluctuation in the system is greatly reduced.
In the process of restraining errors caused by backscattering, the invention ensures that only light input in one direction exists in each resonant cavity, and the light in the reverse direction of the input direction generated by the backscattering cannot be detected by a photoelectric detector, namely, the output light field of the resonant cavity does not contain the backscattering light, so that the system designed by the invention has very good capability of restraining the backscattering. On the other hand, in the conventional single-resonant cavity scheme, modulation signals with different modulation frequencies need to be applied to the forward path and the reverse path to suppress the influence of backscattering, i.e. two phase modulators must be used for carrying out modulation tasks. However, in the scheme of the invention, because the double-ring optical structure eliminates the interference of back scattering, two paths of counterclockwise light and clockwise light can adopt the same modulation frequency, and further, one MIOC can be adopted to realize the modulation, beam splitting and polarization of the two paths of light, thereby greatly reducing the system volume and cost compared with the traditional modulation and demodulation optical path scheme.
In the process of restraining errors caused by Kerr noise, firstly, the propagation medium of light in the resonant cavity is air, and the nonlinear coefficient related to the Kerr effect of the light is far lower than that in the quartz cavity, so that the system noise caused by the Kerr effect can be effectively reduced; secondly, because the light in two directions is independently transmitted after beam splitting, compared with the traditional single-ring resonant cavity scheme, the scheme of the invention does not have the Kerr effect caused by cross modulation, thereby reducing the additional phase shift of two paths caused by the Kerr effect; finally, the invention adopts the intensity modulator to respectively control the light intensity of the two paths, so that the light power of the two paths is always equal, the Kerr noise is further inhibited, and the stability of the scale factor of the whole system can be ensured.
In the aspect of restraining errors caused by polarization fluctuation, on one hand, the invention adopts a full polarization-maintaining light path, and the multifunctional integrated phase modulator and the intensity modulator both have high polarization extinction ratio, so that the light entering the resonant cavity is ensured to be stable linear polarization light; on the other hand, the invention adopts a single-shaft working 2 multiplied by 2 optical fiber coupler as a resonant cavity coupler, has the polarization extinction ratio of more than 20dB, and can effectively inhibit the polarization fluctuation of light caused by external environment in the transmission process in the resonant cavity.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the application.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the application and, together with the description, serve to explain the principles of the application.
Fig. 1 is a schematic structural diagram of a resonant fiber-optic gyroscope optical system according to an exemplary embodiment.
Fig. 2 is a schematic diagram illustrating a noise processing and signal detection flow of a resonant fiber optic gyroscope according to an exemplary embodiment.
Detailed Description
Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, like numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present application, as detailed in the appended claims.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used in this application and the appended claims, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term "and/or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.
It is to be understood that although the terms first, second, third, etc. may be used herein to describe various information, such information should not be limited to these terms. These terms are only used to distinguish one type of information from another. For example, first information may also be referred to as second information, and similarly, second information may also be referred to as first information, without departing from the scope of the present application. The word "if" as used herein may be interpreted as "at … …" or "when … …" or "in response to a determination", depending on the context.
Fig. 1 is a schematic diagram of a low-optical-noise resonant gyroscope system according to an embodiment of the present invention, where the low-optical-noise resonant gyroscope system according to the present embodiment includes a narrow-linewidth tunable Laser, a multifunctional integrated phase modulator MIOC, an intensity modulator IM1, an IM2, a 1 × 2 optical fiber Coupler1, a Coupler3, a 2 × 2 optical fiber Coupler2, and a Coupler 4.
In this embodiment, light emitted by the Laser passes through the multifunctional integrated phase modulator MIOC and then is divided into two paths, namely, a clockwise path (CW path) and a counterclockwise path (CCW path). After passing through the intensity modulator IM1, the counterclockwise light is divided into two beams after passing through the 1 × 2 fiber Coupler1, one beam is converted into an electrical signal by the photodetector PD1, the other beam enters the annular cavity FRR1 formed by the hollow photonic crystal fiber through the 2 × 2 fiber Coupler2, and the emergent light of the resonant cavity is converted into an electrical signal for frequency locking by the photodetector PD2 connected to the Coupler 2. After passing through an intensity modulator IM2, light in a clockwise path is divided into two beams after passing through a 1 × 2 optical fiber Coupler3, one beam is converted into an electric signal by a photoelectric detector PD3, the other beam passes through a 2 × 2 optical fiber Coupler4 and enters an annular cavity FRR2 formed by hollow photonic crystal fibers, emergent light of a resonant cavity is converted into an electric signal by a photoelectric detector PD4 connected to a Coupler4, and the electric signal is demodulated to form gyroscope output.
In this embodiment, the tunable narrow linewidth Laser is a narrow linewidth Laser, the linewidth is 1KHz, the center wavelength is 1550nm, and the power is 30 mW. The multifunctional integrated phase modulator MIOC is a Y-shaped optical waveguide manufactured on a single-crystal niobium lithiumate substrate by adopting proton exchange and annealing technologies. The phase sinusoidal modulation is carried out on the incident light, and the beam splitting function is also played to divide the modulated emergent light into a clockwise path and a counterclockwise path. The intensity modulators IM1 and IM2 are niobium lithiumate crystal intensity modulators, the modulation bandwidth is 30GHz, and the half-wave voltage is 4.5V.
In this example, the light emitted from the tunable narrow linewidth Laser is linearly polarized along the slow axis. The multifunctional integrated phase modulator and the intensity modulator are proton exchange type niobium lithium titanate electro-optic modulators with high polarization extinction ratio. All the beam splitters and couplers are single-axis working devices and have polarization extinction ratio of more than 20 dB. All the tail fibers of the device are polarization maintaining fibers, all the fiber welding points are in 0-degree alignment fusion, and the hollow photonic crystal fibers used by the resonant cavity are also polarization maintaining fibers. On one hand, the full polarization maintaining light path enables light entering the resonant cavity to be linearly polarized light transmitted along the slow axis of the optical fiber; on the other hand, the coupler with the polarization extinction ratio is used as a part of the resonant cavity, so that the polarization fluctuation caused by the external environment in the transmission process of light in the resonant cavity can be effectively inhibited.
In this embodiment, the optical fiber couplers 1 and 3 are 1 × 2 beam splitters, the insertion loss is 0.5dB, and the splitting ratio is 50: 50. The beam splitting ratio of the optical fiber Coupler2 and the Coupler4 is 85:15, and the insertion loss is 0.6 dB.
In this embodiment, the hollow photonic crystal fiber resonant cavities FRR1 and FRR2 are formed by the same hollow photonic band gap fiber, that is, the propagation medium of light in the resonant cavity is air, and the nonlinear coefficient related to the kerr effect is much lower than that of a quartz cavity, thereby effectively reducing the system noise caused by the kerr effect. The hollow photonic crystal fiber resonators FRR1 and FRR2 have exactly the same fiber length and fiber loop diameter and are stacked in parallel. Clockwise and anticlockwise optical fields are respectively input into the hollow photonic crystal fiber resonant cavities FRR1 and FRR2 through Coupler2 and Coupler4, so that only one direction of input light exists in each resonant cavity, and the light in the opposite direction of the input direction generated by back scattering cannot be detected by a photoelectric detector, namely the output optical field of the resonant cavity does not contain back scattering light.
Fig. 2 is a schematic diagram of a noise processing and signal detecting process of a resonant gyroscope according to an embodiment of the present invention, where the present embodiment provides a noise processing and signal detecting method of a resonant gyroscope, the method is based on the system described in embodiment 1, and the method includes the following steps:
the method comprises the following steps: the PD1 detects the light intensity of the counterclockwise path and converts the light intensity into an electric signal, the Proportional Integral (PI) feedback quantity is calculated after the electric signal is collected by a digital processing board, the PI feedback quantity is converted into voltage change and is applied to a voltage modulation port of the IM1, and therefore the light power entering the resonant cavity through the counterclockwise path is controlled to be stabilized at a fixed target value I, and the light power closed-loop feedback1 is formed. The PD3 detects the light intensity of the clockwise path and converts the light intensity into an electric signal, the electric signal is acquired by a digital processing board, then the Proportional Integral (PI) feedback quantity is calculated and converted into voltage change to be applied to a voltage modulation port of the IM2, and therefore the light power entering the resonant cavity of the clockwise path is controlled to be stabilized at a fixed target value I, and the light power closed loop feedback2 is formed. The optical power feedback closed loops 1 and 2 ensure that two paths of optical cavities entering the resonant cavity are stable and equal, greatly improve the stability of the system scale factor and can effectively inhibit Kerr noise.
Step two: the MIOC applies a sinusoidal modulation signal V ═ Msin (2 pi f), i.e. the clockwise path and the counter-clockwise path use exactly the same modulation frequency f and modulation factor. Because the optical structure of the embodiment eliminates the interference of back scattering, one MIOC can be adopted to realize the modulation of two paths of light, and the system volume and the cost are greatly reduced. The modulation signal is generated by a digital processing board.
Step three: the PD2 detects the light intensity output from FRR1, converts the light intensity into an electric signal, and multiplies the electric signal by a sine reference signal after being collected by a digital processing board
Then filtered by a low pass filter LPF1 to obtain a demodulation result of a counterclockwise path, wherein the phase of the sinusoidal reference signal
The phase difference caused by the transmission delay of the anticlockwise path. The PD4 detects the light intensity output from FRR2, converts the light intensity into an electric signal, and multiplies a sinusoidal reference signal after being collected by a digital processing board
Then filtered by a low pass filter LPF2 to obtain a clockwise demodulation result, wherein the phase of the sinusoidal reference signal
The phase difference caused by the clockwise transmission delay.
Step four: the demodulation result of the counterclockwise path is processed by a digital processing board to calculate a Proportional Integral (PI) feedback quantity, and the PI feedback quantity is converted into voltage change to be applied to a frequency modulation port of the laser, so that the center frequency of the laser is always locked on the resonant frequency of the counterclockwise path resonant cavity, and a frequency feedback closed loop is formed. The demodulation result of the clockwise path is the output of the resonant fiber-optic gyroscope system.
Other embodiments of the present application will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure disclosed herein. This application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the application and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the application being indicated by the following claims.
It will be understood that the present application is not limited to the precise arrangements described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The scope of the application is limited only by the appended claims.
Claims (8)
1. A low-optical-noise double-ring parallel resonant fiber optic gyroscope system is characterized by comprising a narrow-line-width tunable Laser, wherein light emitted by the Laser is divided into two paths of transmission, namely a counterclockwise path and a clockwise path, after passing through a multifunctional integrated phase modulator MIOC;
after passing through the intensity modulator IM1, the light in the counterclockwise path is divided into two beams after passing through the 1 × 2 fiber Coupler1, wherein one beam is converted into an electrical signal by the photodetector PD 1; the other beam enters an annular cavity FRR1 formed by hollow photonic crystal fibers through a 2 x 2 fiber Coupler2, and then emergent light of the resonant cavity is converted into an electric signal by a photoelectric detector PD2 connected to Coupler 2;
after passing through the intensity modulator IM2, the clockwise light is divided into two beams after passing through the 1 × 2 fiber Coupler3, and one beam is converted into an electrical signal by the photodetector PD 3; the other beam enters a ring cavity FRR2 formed by hollow photonic crystal fibers through a 2 x 2 fiber Coupler4, and emergent light of the resonant cavity is converted into an electric signal through a photoelectric detector PD4 connected to Coupler 4;
the hollow photonic crystal fiber resonant cavities FRR1 and FRR2 are formed by the same polarization-maintaining type hollow photonic crystal fibers, have the same fiber length and fiber ring diameter, and are stacked in parallel;
wherein, all the optical fiber welding points are in 0-degree alignment fusion.
2. The system of claim 1, wherein the multifunctional integrated phase modulator MIOC is a Y-type optical waveguide fabricated on a niothium lithiumate substrate using proton exchange technology.
3. A low-optical-noise dual-ring parallel resonant fiber-optic gyroscope system as claimed in claim 1, wherein the multifunctional integrated phase modulator MIOC applies a sinusoidal modulation voltage V ═ Msin (2 pi f) across it, and the sinusoidal signal is generated by the digital processing board, i.e. the clockwise path and the counter-clockwise path use the same modulation frequency f and modulation coefficient.
4. The dual-ring parallel resonant fiber optic gyroscope system with low optical noise of claim 1, wherein the intensity modulator IM1, the photodetector PD1 and the digital processing board form a Power Feedback 1; the intensity modulator IM2, the photoelectric detector PD3 and the digital processing board form a Power Feedback2 of optical Power closed loop; the optical power closed loop feedback enables the optical power entering the resonant cavity in a clockwise way and a counterclockwise way to be the same and stable.
5. A low optical noise dual-ring parallel resonant fiber optic gyro system as claimed in claim 1, wherein said intensity modulators IM1, IM2 each have a polarization extinction ratio above 30dB, and all beam splitters and couplers are single-axis polarization maintaining devices.
6. The low-optical-noise double-ring parallel resonant fiber optic gyroscope system of claim 1, wherein the output signals of the photodetectors PD2 and PD4 are collected and calculated by a digital processing board to obtain the phase-locked demodulation outputs of the positive and negative paths.
7. The low-optical-noise double-ring parallel resonant fiber optic gyroscope system of claim 1, wherein the Laser, the photodetector PD2 and the digital processing board form a frequency closed-loop Feedback frequency Feedback so that the center frequency of the Laser is always locked at the resonant frequency of the counterclockwise resonator.
8. A method for processing noise and detecting signal of resonant gyroscope, which is implemented based on a low optical noise double-ring parallel resonant fiber-optic gyroscope system as claimed in any one of claims 1-7, and which comprises:
the method comprises the following steps: the PD1 detects the light intensity of the counterclockwise path and converts the light intensity into an electric signal, the electric signal is acquired by a digital processing board, then the Proportional Integral (PI) feedback quantity is calculated and converted into voltage change to be applied to a voltage modulation port of the IM1, and therefore the light power entering the resonant cavity from the counterclockwise path is controlled to be stabilized at a fixed target value I, and light power closed loop feedback1 is formed; the PD3 detects the light intensity of the clockwise path and converts the light intensity into an electric signal, the electric signal is acquired by a digital processing board, then the Proportional Integral (PI) feedback quantity is calculated and converted into voltage change to be applied to a voltage modulation port of the IM2, and therefore the optical power entering the resonant cavity of the clockwise path is controlled to be stabilized at a fixed target value I, and optical power closed loop feedback2 is formed;
step two: applying a sine modulation signal V-Msin (2 pi f) to the MIOC, wherein the sine modulation signal is generated by a digital processing board and converted into voltage;
step three: the PD2 detects the light intensity output from the FRR1 and converts the light intensity into an electric signal, the electric signal is multiplied by a sine reference signal after being collected by a digital processing board, then the demodulation result of a counterclockwise path is obtained by filtering the signal by a low pass filter LPF1, the PD4 detects the light intensity output from the FRR2 and converts the light intensity into an electric signal, the electric signal is multiplied by another sine reference signal after being collected by a digital processing board, and then the demodulation result of a clockwise path is obtained by filtering the signal by a low pass filter LPF 2;
step four: the demodulation result of the counterclockwise path is processed by a digital processing board to calculate Proportional Integral (PI) feedback quantity, and the PI feedback quantity is converted into voltage change to be applied to a frequency modulation port of the laser, so that the central frequency of the laser is always locked on the resonant frequency of the counterclockwise path resonant cavity to form a frequency feedback closed loop; the demodulation result of the clockwise path is the output of the resonant fiber-optic gyroscope system.
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| CN113566806B (en) * | 2021-07-26 | 2024-05-10 | 浙江大学 | Single-polarization low-optical-noise space micromirror coupling system and digital signal processing system |
| CN114362831B (en) * | 2021-12-28 | 2024-01-26 | 杭州电子科技大学 | 2-line-4-line decoder based on optical single-ring mosaic resonant cavity |
| CN115112113B (en) * | 2022-07-18 | 2023-03-03 | 哈尔滨工业大学 | Device and method for compensating relative intensity noise error of resonant fiber-optic gyroscope |
| CN116400456A (en) * | 2023-03-24 | 2023-07-07 | 雨树光科(深圳)有限公司 | Adjustable optical power beam splitter, control method and optical fiber gyroscope |
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