132 results about "Fiber optical gyroscope" patented technology

The invention relates to the technical field of optical fiber sensing and fault diagnosis, in particular to an optical fiber gyroscope fault monitoring method and system. The method comprises the following steps: extracting four-dimensional characteristics of phase difference, light intensity fluctuation, polarization state drift and temperature drift from an output signal of an optical fiber gyroscope, and constructing a high-dimensional characteristic matrix after unifying a time reference; establishing a dynamic prediction model based on historical data to generate a residual matrix, and orthogonally separating the residual into an internal structure abnormal signal and an environment disturbance signal through covariance characteristic decomposition; mapping the structure residual error sequence into a topological graph, calculating an evolution index in real time, and capturing a fault gradient trend in combination with sliding window gradient analysis; a multi-dimensional vector is constructed by fusing topological features, an adaptive classifier of an online Gaussian mixture model is adopted to identify a fault mode and quantify a health index, and meanwhile, a health measurement result is fed back to a prediction model and topological analysis parameters to realize closed-loop optimization. According to the invention, full-process adaptive monitoring from anomaly detection to health measurement is realized.

The invention relates to the technical field of optical fiber gyroscopes, in particular to a temperature control optical fiber inertial navigation structure and a design method thereof.The design method comprises the following steps of detecting heat flow direction changes, extracting offset numbers, generating frequency density, analyzing the thickness contour and deformation coincidence rate, outputting correction gradients, matching jump trends and structural connection, and generating a priority sequence; and screening offset channel numbers, integrating compression and deformation trends, and outputting a design scheme. According to the method, by capturing heat flow direction change points and extracting offset area numbers, density expression of a heat energy propagation path is achieved, the space recognition capability of thermal disturbance is enhanced, the structural adaptability of thermal response is improved, and stable conduction of heat flow between structural levels is optimized through sequence integration of a temperature jump trend and a connection relation; and extracting a stable channel number in a lateral offset state, enhancing path directivity, integrating a multi-region compression trend and structural deformation mapping, and improving thermal situation identification capability and structural thermal adaptability.

A loop pigtail compensation method for a fiber-optic gyroscope, and a fiber length compensator. The fiber length compensator is fixed on a loop pigtail of the fiber-optic gyroscope, and the fiber length compensator includes a peripheral fiber loop and an expansion-and-contraction shaft core capable of realizing deformation of expanding and contracting; and upon detecting that there is a drift in an output of the fiber-optic gyroscope, a length of the peripheral fiber loop of the fiber length compensator is changed by adjusting a coefficient of linear expansion of the expansion-and-contraction shaft core of the fiber length compensator, so that the compensation for the loop pigtail of the fiber-optic gyroscope is realized, and the problem of low accuracy of online adjustment of the pigtail of the fiber-optic gyroscope is solved.

The utility model discloses a shell structure for an optical fiber gyroscope, which comprises an optical fiber gyroscope shell, a shell cover is mounted at the upper end of the optical fiber gyroscope shell through bolts, a bottom plate is welded at the bottom of the optical fiber gyroscope shell, a mounting seat is connected to the bottom of the bottom plate through bolts, and a sealing structure is mounted between the optical fiber gyroscope shell and the shell cover. According to the utility model, the sealing structure is arranged between the optical fiber gyroscope shell and the shell cover, when the shell cover is arranged on the optical fiber gyroscope shell, the sealing ring extrudes the convex ring plate, and then the sealing ring extends into the convex groove under the elastic action of the spring, so that the sealing performance between the optical fiber gyroscope shell and the shell cover is better; the influence of the external environment on the internal optical fiber gyroscope is reduced, the stability and reliability of the optical fiber gyroscope are improved, and the shell and the shell cover of the optical fiber gyroscope are further fastened through the first flange and the second flange.

The application provides a filtering optimization method and system for an inertial measurement unit fiber-optic gyroscope. The three-dimensional vibration signal of the inertial measurement unit fiber-optic gyroscope is collected, and the vibration modal characteristic data is generated through short-time Fourier transform. The magnetic field strength of the gyroscope is dynamically adjusted according to the data, and the environmental vibration energy is converted into current data based on the adjusted magnetic field strength. The original angular velocity data output by the gyroscope is combined, a double-channel convolutional neural network is used to extract first and second noise features from the current data and the original angular velocity data respectively, and preliminary denoising data is output after fusion. The preliminary denoising data is subjected to variational modal decomposition, and the effective modal components are selected according to a preset kurtosis rule to obtain target angular velocity data, which is used to realize filtering optimization of the gyroscope. The technical scheme provided by the application improves the measurement accuracy and filtering optimization effect of the inertial measurement unit fiber-optic gyroscope.

The utility model discloses an active heave compensation control system of a crane, which relates to the technical field of active heave compensation of cranes and comprises a first Hall encoder, a first capacitive grating displacement sensor, a second capacitive grating displacement sensor, a second Hall encoder, a lifting hook optical fiber gyroscope and a ship optical fiber gyroscope, the upper computer receives data acquired by the first Hall encoder, the second Hall encoder, the first capacitive grating displacement sensor, the second capacitive grating displacement sensor, the lifting hook optical fiber gyroscope and the ship optical fiber gyroscope, and generates an active heave compensation control signal according to the received data; and the field controller is used for receiving the active heave compensation control signal sent by the upper computer and controlling the crane to carry out active heave compensation. According to the utility model, the crane actuating mechanism is controlled through the field controller, so that the heaving motion of the load can be effectively compensated, and the load stability is improved.

The invention discloses a shipborne intelligent navigation method based on a satellite-inertial combination technology. The method comprises the steps of system initialization, navigation in a satellite signal normal state, navigation in a satellite signal disconnection state, navigation in a satellite signal denial environment, navigation mode adaptive switching and similar route library dynamic updating. The invention relates to the technical field of intelligent navigation. According to the ship-borne intelligent navigation method based on the satellite-inertial combination technology, all-weather and high-reliability navigation of a ship in different signal environments is realized through information fusion of multi-source sensors such as a high-precision GNSS receiver, an optical fiber gyroscope, an MEMS inertial unit, an underwater acoustic velocimeter and a geomagnetic module in combination with intelligent matching of a similar route library. The method is particularly suitable for ship intelligent navigation in satellite signal disconnection and denial environments, and has the characteristics of strong anti-interference capability, high intelligent degree and strong self-learning capability.

The application relates to the technical field of fiber-optic gyroscopes, in particular to a preparation method of a two-in and two-out mirror image fiber-optic ring, which comprises the following steps: measuring two optical fibers with required lengths; marking the endpoints and the midpoints of the two optical fibers respectively; calculating a winding sequence change point and marking the same on the two optical fibers respectively; winding the two optical fibers on a fiber-optic ring skeleton in a mirror image symmetrical manner alternately by adopting a quadrupole symmetrical winding method until the winding sequence change point; changing the winding sequence of the two optical fibers; repeating steps d and e until the endpoint marks at the two ends of the optical fibers; and leading out four optical fiber tail fibers from the fiber-optic ring skeleton and fixing the same. According to the preparation method of the two-in and two-out mirror image fiber-optic ring, the two optical fiber rings have a mirror image relationship in space, so that the temperature phase errors generated by the two wound optical fiber rings are consistent, the phase errors caused by temperature changes in the Shupe effect can be compensated after joint signal processing, and the precision of the fiber-optic gyroscope is further improved.

The application relates to a split modular three-axis integrated optical fiber gyroscope structure, which comprises an optical fiber gyroscope control assembly and three optical fiber gyroscope optical path assemblies. The four assembly structures are independent of each other and are only connected through wire harnesses, can be flexibly laid according to system-level application requirements, and are suitable for various types of system products. The assembly is modular, compact in layout, and reasonable in material selection, and high reliability and high applicability of the three-axis integrated optical fiber gyroscope are realized under small volume and weight. The heating components are installed in the optical fiber gyroscope control assembly, complete isolation between the heating device and the polarization maintaining optical path is realized, the influence of the heating device temperature change on the optical path is avoided, and the starting characteristics and temperature performance of the gyroscope are improved; the internal material of the optical fiber gyroscope optical path assembly is optimized, the configuration is refined, the weight is reduced, the high strength and high rigidity characteristics are ensured, the optical fiber is not suspended, the fiber radius is maximized, the mechanical environmental adaptability of the gyroscope is strong, and the long-term stability of the gyroscope precision is ensured.

Embodiments of the present invention provide a system for mitigating dual domain vulnerabilities using fiber optic gyroscope and quantum cryptography. The system is configured for receiving an alert associated with misappropriation of an interaction processing device, via a quantum communication channel, in response to receiving the alert, extracting monitoring data associated with the interaction processing device from one or more monitoring devices, analyzing the alert received via the quantum communication channel and the monitoring data extracted from the one or more monitoring devices, determining unauthorized access of the interaction processing device based on analyzing the alert and the monitoring data, and performing one or more actions to mitigate vulnerabilities associated with the unauthorized access of the interaction processing device.

The invention provides an optical fiber gyroscope capable of dynamically adjusting a light source. The optical fiber gyroscope comprises a light source driving control circuit, a signal processing circuit, a temperature sensor and a light source module, the light source driving control circuit comprises a constant current source module, a temperature control module and a dual-channel digital-to-analog conversion module; the signal processing circuit comprises a programmable logic device; the temperature sensor is connected with the programmable logic device; the programmable logic device is used for generating constant current voltage and temperature control voltage in a digital form according to the environment temperature collected by the temperature sensor, and sending the constant current voltage and the temperature control voltage to the dual-channel digital-to-analog conversion module; the dual-channel digital-to-analog conversion module is used for converting the constant current voltage into a first analog voltage and outputting the first analog voltage to the constant current source module so as to dynamically adjust the output current of the constant current source module, and converting the temperature control voltage into a second analog voltage and outputting the second analog voltage to the temperature control module so as to dynamically adjust the temperature set point of the temperature control module; the output of the constant current source module and the output of the temperature control module are connected with the light source module and used for providing dynamically-adjusted driving current and working temperature for the light source module.

The utility model discloses a mining attitude instrument which comprises a box body, an inclinometer assembly, a PCB (Printed Circuit Board) assembly, a gyroscope assembly, a rotary table part, a display module, a cross laser mark and a storage battery, the box body comprises a base and a box cover; an inclinometer assembly, a rotary table component and a storage battery are sequentially arranged on the base from left to right; the rotary table component comprises a rotary table base assembly, a worm and gear mechanism, a travel switch and a stepping motor. The PCB assembly comprises a main control board and a multifunctional board; a display module is arranged on the inner wall of the front side of the box cover, a cross-shaped laser mark is arranged on the upper portion of the right side wall, and a membrane switch is arranged on the outer wall of the front side of the box cover corresponding to the display module. By adopting the combination of the optical fiber gyroscope and the inclinometer, the size and the weight of the north seeker are reduced, the cost is reduced, and the north seeker can quickly seek north; by arranging the rotary table component, the optical fiber gyroscope can be driven to rotate to different positions; and through the arrangement of the cross cursor, hole alignment is facilitated.

The invention discloses an optical polarizer and an optical fiber gyroscope. The optical polarizer comprises a mode hybridization region, a mode coupling region and a light beam combination region, the input end of the mode coupling area is coupled with the output end of the mode hybridization area, and the first output end and the second output end of the mode coupling area are respectively coupled with the first input end and the second input end of the light beam combination area; the mode hybridization region receives input light containing a TE0 mode and a TM0 mode, converts the TM0 mode into a TE1 mode, and then inputs the TE1 mode and the original TE0 mode into the mode coupling region; the mode coupling region outputs the original TE0 mode from the first output end of the mode coupling region, converts the TE1 mode into the TE0 mode, and then outputs the converted TE0 mode from the second output end of the mode coupling region; and the light beam combining area is used for carrying out beam combining processing on the two received beams in a TE0 mode. According to the scheme, the polarization purpose can be achieved, and meanwhile the effect of reducing optical power loss is achieved.

The utility model discloses a super-radiation light-emitting diode light source driving circuit, and relates to the technical field of inertial navigation optical fiber gyroscope light source driving. The positive control end and the negative control end of the TEC temperature control module are respectively connected with the cold end and the hot end of the super-radiation light-emitting diode light source and are used for controlling the temperature of the super-radiation light-emitting diode light source to be within a set range, and the constant power module mainly provides stable and constant driving current for the super-radiation light-emitting diode light source; according to the utility model, stable and constant driving current can be provided for the super-radiation light-emitting diode light source, the super-radiation light-emitting diode light source TEC module can be controlled to carry out temperature compensation, and the optical power change caused by temperature change is reduced, so that the precision index of the optical fiber gyroscope is improved, the circuit structure is simple, the miniaturization design can be realized, and the cost is low. And the size and the weight of the optical fiber gyroscope are reduced.

A method for manufacturing a fiber optic gyroscope ring to reduce the gyroscope scaling factor includes the following steps: If the expansion coefficient reaches a stabilization threshold, a scaling factor calibration system is activated. The scaling factor of the gyroscope is adjusted according to a preset calibration procedure. Based on the scaling factor calibration results, it is determined whether the measurement accuracy meets the preset accuracy requirements. Equivalent radius data is acquired over the entire temperature range, and the stability of the equivalent radius with temperature variation is analyzed. Based on the stability data of the equivalent radius, a performance stability evaluation model is established to describe the relationship between performance stability and equivalent radius stability. A preset performance optimization algorithm is used to adjust the winding process parameters so that the equivalent radius of the ring tends to stabilize over the entire temperature range. By monitoring the change trend of the equivalent radius in real time, it is determined whether the performance stability reaches the preset optimization threshold.

A gyroscope shell is provided with a left cavity and a right cavity, a light source module and a power module are installed in the left cavity, an optical module is installed in the right cavity, and a curved surface groove for an optical fiber to pass through is formed between the two cavities; the optical module comprises a ring base, an optical fiber ring, a ring shell, a coupler and a Y waveguide; the optical module is reversely mounted through a screw arranged at the bottom of the gyroscope shell; the ring base and the ring shell are made of magnetic shielding materials to overcome the influence of a magnetic field on the optical fiber ring, the circuit control mainboard is fixedly connected to the ring shell, and the power panel is detachably installed on the power panel bracket. The optical fiber gyroscope provided by the invention can overcome the influence of temperature change, magnetic field and vibration impact on measurement precision and stability, and the reliability of the optical fiber gyroscope is effectively improved.

The invention discloses an optical fiber gyroscope, which is suitable for the technical field of sensors and comprises a first substrate, a first planar optical waveguide coupler, a second planar optical waveguide coupler, at least one optical fiber resonant cavity and a first optical fiber. The first substrate comprises a first surface and a second surface which are opposite. The first planar optical waveguide coupler and the second planar optical waveguide coupler are arranged on the first surface. The at least one optical fiber resonant cavity is arranged on the first surface and extends into the first substrate from the first surface, and the at least one optical fiber resonant cavity is located between the first planar optical waveguide coupler and the second planar optical waveguide coupler in the direction parallel to the second surface. And the orthographic projection of the at least one optical fiber resonant cavity on the second surface is annular. The first optical fiber is arranged in the at least one optical fiber resonant cavity. According to the technical scheme, the test precision and the integration degree of the optical fiber gyroscope are improved.

The present invention discloses a system and method for compensating the optical path power of a fiber optic gyroscope using a binary modulation depth method, and belongs to the technical field of fiber optic gyroscopes. The system includes a fiber optic gyroscope closed-loop system and a signal processing circuit. In the signal processing circuit, the photocurrent signal detected by the photodetector is amplified and converted into a digital signal. In the FPGA digital logic circuit, the signal is modulated using a binary modulation depth method, and the optical path power and angular velocity in the digital signal are demodulated using a digital operation method. The generated feedback signal is fed back to the current control port of the wide-spectrum light source and the phase modulator of the Y-waveguide integrated optical chip. The present invention uses a shared A / D detection channel for optical path power compensation and fiber optic gyroscope angular velocity detection, eliminating the need for an additional optical power detection module. Real-time compensation of the optical path power of the fiber optic gyroscope can be achieved without affecting the performance and size of the fiber optic gyroscope, thereby increasing the reliability and stability of the fiber optic gyroscope.

The invention discloses a precision test environment for an ultrahigh-precision optical fiber gyroscope. The precision test environment comprises a high-stability workbench and a closed container, the high-stability workbench comprises a shell, a table top and a double-layer mass base. The double-layer mass base is arranged in the shell, and the upper surface of the double-layer mass base supports the table top through evenly-distributed ground feet. The double-layer quality base is used for realizing the overall stability of a full frequency band; the closed container is of a double-layer heat preservation structure. Thin-film resistance heating pieces are attached to the inner side of an inner heat preservation layer and the outer side of an outer heat preservation layer. The thin-film resistor heating sheet is connected with an external temperature control computer through a signal line; the ultrahigh-precision optical fiber gyroscope is arranged in the closed container, and the temperature control computer performs power-on and power-off control on the thin-film resistor heating sheet according to real-time temperature data around the optical fiber gyroscope; and the closed container is arranged on the surface of the high-stability workbench. According to the precise testing environment, the high-stability workbench is provided, and the high-stability temperature environment is provided.

The application discloses a high-polarization-extinction-ratio integrated Y waveguide structure based on a thin film lithium niobate, relates to the fields of microwave photonics, integrated optoelectronics and high-precision inertial sensing technology, and comprises a substrate, a lower cladding layer, a thin film lithium niobate layer and an upper cladding layer from bottom to top; and the polarization extinction ratio of the device is significantly improved according to the application; in view of the problem of poor polarization extinction ratio performance of the current monolithic integrated thin film lithium niobate Y waveguide due to the lack of an on-chip efficient polarization structure, the application creatively utilizes mode parity symmetry for filtering; the energy zero point position of the TE1 mode is determined by the waveguide electromagnetic field eigen equation and does not drift with the external environment temperature or stress; unlike the directional coupler relying on nanoscale gaps or the subwavelength grating with a minimum line width; the end-to-end transmission loss of the polarization and filtering of the application can be controlled at a very low level, so that the optical power margin and the overall signal-to-noise ratio of the fiber-optic gyroscope system detection end are significantly improved.

The invention relates to a three-axis integrated optical fiber gyroscope which comprises a light source base assembly and three gauge outfit assemblies, the light source base assembly and the three gauge outfit assemblies are installed on a system body structure, and the light source base assembly and the three gauge outfit assemblies form the complete three-axis integrated optical fiber gyroscope. The light source base assembly and the meter head assembly are connected through a wire harness. The light source base assembly generates light signals, the light signals enter the three gauge outfit assemblies after light splitting operation is completed in the light source base assembly, the light signals are subjected to light splitting, transmission and interference processes in the gauge outfit assemblies to form interference light signals, then the interference light signals are transmitted back to the gauge outfit assemblies, and photoelectric conversion is conducted on the gauge outfit assemblies to obtain electric signals. Through the process design that the box body is processed and matched with the slot position, the bending and abrasion risks of the optical fiber are reduced, the service life of the optical fiber is effectively prolonged, and finally the design targets of low power consumption and low cost of the three-axis integrated gyroscope are achieved.

The invention discloses a three-axis integrated optical fiber gyroscope packaging structure with high environmental adaptability, and relates to the field of optical fiber gyroscopes. A three-axis integrated optical fiber gyroscope packaging structure with high environmental adaptability comprises a frame-type structure, the frame-type structure is a cylinder with a concave hexagonal structure, and a hollow cavity is formed in the frame-type structure; the rectangular frame structure is mounted in the hollow cavity of the frame structure, and the rectangular frame structure is fixedly connected with the hexagonal structure; the transverse partition plate is arranged at the bottom of the rectangular frame-shaped structure; through the arrangement of the transverse partition plates, the frame type structure can be divided into six independent mounting bins including a front mounting bin, a rear mounting bin, a left mounting bin, a right mounting bin, an upper mounting bin and a lower mounting bin; according to the invention, an equal-rigidity core frame structure is adopted, and the mounting surface of each component is designed into an integrated frame with balanced rigidity, so that resonance amplification caused by rigidity difference of a traditional structure is avoided, and zero offset change and noise in a vibration environment are effectively reduced.

The application discloses a machine learning assisted fiber-optic gyroscope polarization locking and slow drift compensation system. The system can intelligently search and predict the relationship between the fiber-optic gyroscope interference error signal and the incident light polarization direction by introducing the neural network in machine learning, and feed back the predicted optimal value to the hardware system for compensation, thereby realizing the functions of fiber polarization locking and suppressing the intensity slow drift of the output signal. The system comprises a coherent light source, a Glan laser prism, a first polarization beam splitter, a first mirror, a first Faraday rotator, a first half-wave plate, a liquid crystal modulator, a polarization maintaining optical fiber, a phase modulator, a second Faraday rotator, a second half-wave plate, a second mirror, a third half-wave plate, a second polarization beam splitter, a photodetector, a computer and a signal generator. The application also discloses a machine learning assisted fiber-optic gyroscope polarization locking and slow drift compensation method realized by using the above system.

The invention discloses a polarization-maintaining hollow-core anti-resonance optical fiber with an arc-shaped cladding. The polarization-maintaining hollow-core anti-resonance optical fiber comprises a fiber core region and a cladding region, the fiber core area is formed by surrounding of the cladding area and is in a long strip shape. The cladding area comprises a cladding tube, a half-tube structure and an outermost sleeve; the cladding tube comprises two nested circular tubes; the two nested circular pipes are tangent to each other, and the outer circular pipe is in contact with the outermost sleeve; the whole optical fiber structure meets central symmetry. The hollow-core anti-resonance optical fiber has the unique advantages of low loss, low nonlinearity, high temperature stability and the like, and optical signals can be well limited in the fiber core for transmission. The effective mode refractive index of the polarization state is modulated through the y-pol reverse cross coupling of the quartz wall of the half-tube structure to the fundamental mode, and meanwhile the fundamental mode of the air fiber core is effectively limited through the nested tube in the cladding area, so that the low-loss performance is considered while high birefringence is achieved. And support is provided for application in the fields of signal transmission, precision sensing, optical fiber gyroscopes and the like.

The invention belongs to the technical field of fault detection, and discloses a fault detection method, system and device of an optical fiber gyroscope and a storage medium, the method comprises the following steps: obtaining historical operation parameters of the optical fiber gyroscope during normal operation, and preprocessing the historical operation parameters to obtain an operation parameter sample set; performing clustering processing on the operation parameter sample set based on a preset clustering algorithm to obtain a plurality of normal behavior clusters; acquiring real-time operation parameters of the optical fiber gyroscope, and performing anomaly analysis on the real-time operation parameters based on the normal behavior cluster to obtain an anomaly analysis result; based on the abnormal analysis result and a pre-constructed fault occurrence condition, judging whether the optical fiber gyroscope has a fault or not, and if so, generating fault early warning information; and carrying out visual display on the fault early warning information. According to the method, the fault condition of the optical fiber gyroscope in the operation process can be accurately and quickly found, the optical fiber gyroscope can be conveniently calibrated and served in the later period, and the reliability of the optical fiber gyroscope in the operation process is improved.

The present invention belongs to the technical field of fiber optic gyroscopes and proposes an anti-shock method for an interferometric fiber optic gyroscope based on pre-judgment of an integrator. Based on the traditional closed-loop feedback system of the fiber optic gyroscope, the integrator in the closed-loop feedback system is pre-judged to perform phase compensation adjustment so that the difference between the closed-loop tracking rate and the actual carrier rotation speed is always less than the π phase shift, ensuring that the closed-loop feedback value can effectively track the actual carrier rotation speed. By real-time processing and outputting the accumulated phase compensation amount and the current integrator output, the actual angular velocity change that the fiber optic gyroscope is sensitive to is obtained. The present invention can ensure that the fiber optic gyroscope can still maintain accuracy and normal operation when subjected to a large impact, avoiding the measurement error caused by the working point offset. At the same time, the original optical path and circuit structure of the fiber optic gyroscope are not changed, and the cross-fringe phenomenon is corrected only through the optimization algorithm, meeting the low-cost and miniaturization requirements of the fiber optic gyroscope and being suitable for application in various occasions.

The application discloses a method and device for reducing detection noise of an optical fiber gyroscope. The method comprises: constructing a finite element simulation model of an optical modulator; the simulation model comprises equivalent transverse resistance and capacitance and equivalent longitudinal resistance and capacitance; based on the simulation model, equivalent resistance and capacitance parameters of the optical modulator under different electrode parameters are calculated respectively, and multiple sets of equivalent resistance and capacitance parameters are obtained; the electrode parameters comprise electrode width and electrode spacing; based on each set of equivalent resistance and capacitance parameters, a quantitative relationship between effective modulation signal drift time and drift amount on the optical modulator and the electrode parameters is determined; based on the quantitative relationship, final electrode parameters of the optical modulator under a set requirement are determined; the set requirement comprises a set drift amount and a set drift time. According to the application, the output drift of the optical modulator can be reduced, the reset error of the optical fiber gyroscope can be reduced, and the detection noise of the optical fiber gyroscope can be reduced.

The invention discloses an all-fiber type isolated circular polarizer and a preparation method thereof. The all-fiber type isolation circular polarizer comprises three parts, namely a fiber type polarizer, a fiber type lambda / 4 wave plate and a holding fiber, the fiber type polarizer and the fiber type lambda / 4 wave plate with a certain length are connected in a manner that an axial included angle is 45 degrees, the lambda / 4 wave plate is prepared from novel high-birefringence crystal derived fibers, and the holding fiber is made of high-birefringence crystal derived fibers. The optical fiber type polarizer is composed of a single-polarization optical fiber, a D-type optical fiber, a 45-degree inclined grating or any optical fiber type device with a polarization effect. The all-fiber device which is manufactured based on an improved welding mode and integrates circular polarization and isolation characteristics has the advantages of high temperature resistance, ultra wide band, high performance, low cost, compactness, easiness in integration and the like; the method can be applied to the fields of optical fiber gyroscopes, AR / VR equipment, optical fiber current sensors, high-power laser, optical fiber communication, medical imaging, quantum communication, material structure analysis and measurement and the like.

This invention provides a resonant fiber optic gyroscope signal processing system based on FPGA and ARM, including an A / D converter, an FPGA terminal, an ARM terminal, a D / A converter, and a resonant fiber optic gyroscope. The resonant fiber optic gyroscope includes a tunable semiconductor laser, an optical isolator, a beam splitter, a first phase modulator, a second phase modulator, a first circulator, a second circulator, a coupler, a fiber optic ring resonant cavity, a first photodetector, and a second photodetector. The A / D converter receives the photodetector signals from the gyroscope system; the D / A converter outputs the phase modulation signals and laser control signals; and the AXI bus protocol, UART protocol, and TLV protocol are used to control the FPGA output signals, transmit signals from the ARM terminal, and process the gyroscope output data. This invention allows for the control of required parameters and the acquisition, processing, and observation of gyroscope output signals on a host computer, simplifying the parameter debugging process and improving system debugging efficiency.

The invention discloses a multi-event failure mode FMEA analysis method for an optical fiber gyroscope, and relates to the technical field of optical fiber gyroscopes. Comprising the following steps: establishing a multi-event failure mode database and management software; clicking a plurality of failure modes by utilizing the management software, and generating a multi-top event failure mode assembly and a multi-top event fault tree; the multi-top event fault tree comprises a plurality of bottom events, a plurality of middle events and a plurality of top events; and based on the failure mode assembly and the multi-top event fault tree, performing troubleshooting and influence analysis on the failure mode in combination with troubleshooting priorities. The problem of FMEA analysis work when a plurality of top events occur on the optical fiber gyroscope at the same time is solved.