Fiber-optic gyroscope and method capable of realizing rapid self-detection during starting in wide temperature range

Abstract

The invention provides a fiber-optic gyroscope and a method capable of realizing rapid self-detection during starting in a wide temperature range. Comprising a fiber-optic gyroscope light path part, a pre-stage amplification and analog-to-digital conversion circuit, a demodulation information classification module, a rate information demodulation module, a step wave signal generator, a self-detection information demodulation module, a state early warning and output module, a modulation signal generation module, a modulation signal combination module and a digital-to-analog conversion and post-stage amplification circuit.

Description

Technical Field

[0001] This invention relates to the field of fiber optic gyroscope technology, and in particular to a fiber optic gyroscope and method capable of achieving rapid self-testing upon power-on over a wide temperature range. Background Technology

[0002] Fiber optic gyroscope based on The fiber optic gyroscope achieves angular velocity measurement through a closed fiber optic loop that decomposes two counter-propagating light waves generated by the same light source. When the carrier experiences angular velocity motion, the two beams interfere with each other due to the optical path difference, resulting in a phase shift. This phase difference is detected to sense the carrier's angular velocity. The all-solid-state structure and lack of moving parts in fiber optic gyroscopes significantly reduce maintenance requirements, leading to their widespread application in aerospace, marine navigation, military guidance, and industrial control. In high-reliability scenarios such as attitude control, guidance, and positioning, the fiber optic gyroscope's rapid self-testing capability over a wide temperature range directly impacts the system's reliability and fault tolerance.

[0003] Within a wide temperature range, the temperature control process during gyroscope light source startup can cause fluctuations in gyroscope optical power, leading to saturation or severe fluctuations in the photodetector's response signal. Simultaneously, the asynchronous thermal response hysteresis characteristics of optical components and control circuitry, such as the light source wavelength, the integrated optical modulator's half-wave voltage, and the photodetector's response, can interfere with phase detection results or amplify errors. Traditional detection methods require interruption of operation or reliance on external equipment; generally, embedded detection methods depend on a stable detector response signal, making rapid detection after power-on difficult over a wide temperature range. Currently, there is no method for rapid self-testing of fiber optic gyroscopes after power-on over a wide temperature range. Summary of the Invention

[0004] This invention aims to provide a fiber optic gyroscope and method that enables rapid self-testing upon power-on over a wide temperature range. This addresses the problem that fiber optic gyroscopes cannot quickly self-test after power-on over a wide temperature range due to factors such as saturated or large fluctuations in the optical power output of the photodetector and asynchronous thermal response hysteresis characteristics of gyroscope components. The invention achieves rapid self-testing upon power-on over a wide temperature range, improving the gyroscope's health management capabilities and long-term reliability.

[0005] The technical solution of this invention: In a first aspect, this application provides a fiber optic gyroscope capable of rapid self-testing upon power-on over a wide temperature range, comprising: 1. a fiber optic gyroscope optical path section; 2. a pre-amplifier and analog-to-digital converter circuit; 3. a demodulation information classification module; 4. a rate information demodulation module; 5. a stepped wave signal generator; 6. a self-test information demodulation module; 7. a status warning and output module; 8. a modulation signal generation module; 9. a modulation signal combination module; and 10. a digital-to-analog converter and post-amplifier circuit, wherein: Fiber optic gyroscope optical path section 1 implements the fiber optic gyroscope Effect; the preamplifier and analog-to-digital converter circuit 2 amplifies the electrical signal converted by the photodetector and converts the analog electrical signal into a digital signal for use by the demodulation information classification module; the demodulation information classification module 3 divides the digital signal into the rate signal to be demodulated and the self-detection signal to be demodulated; the rate signal to be demodulated is sent to the rate information demodulation module 4, which demodulates the rate signal according to the demodulation timing and generates a step signal corresponding to the rate information, which is sent to the step wave signal generation module 5; the self-detection information demodulation module 6 receives the self-detection signal to be demodulated, completes the self-detection information demodulation, and transmits the demodulation result to the status warning and output module 7; the status warning and output module 7 calculates and judges whether the current functional state of the gyroscope is normal according to the self-detection threshold, and completes the gyroscope self-detection and working status output; the modulation signal generation module 8 generates a square wave or four-state modulation signal according to the gyroscope closed-loop control timing and periodically replaces it with a modulation depth of The self-detection modulation signal; the signals generated by the stepped wave signal generation module 5 and the modulation signal generation module 8 are sent to the modulation signal combination module 9, which superimposes the two signals into digital quantities and sends them to the digital-to-analog converter and subsequent amplifier circuit 10; the subsequent amplifier and digital-to-analog converter circuit 10 performs digital-to-analog conversion on the superimposed combined modulation signal and amplifies the signal before outputting it to the integrated optical modulator in the optical path section of the fiber optic gyroscope.

[0006] Specifically, the optical path section 1 of the fiber optic gyroscope includes a light source, a coupler, an optical fiber ring, an integrated optical modulator, and a photodetector. The coupler is connected to the light source, the integrated optical modulator, and the photodetector respectively. The beam splitting port of the integrated optical modulator is then connected to the optical fiber ring. The light emitted from the light source is split into two beams after passing through the coupler and the integrated optical modulator. These beams propagate into the optical fiber ring in clockwise and counterclockwise directions respectively, and then return through the integrated optical modulator and the coupler to enter the photodetector. The electrodes of the integrated optical modulator are connected to the subsequent amplification and analog-to-digital conversion circuit 10 to convert the electrical signal into phase modulation of the optical signal. The photodetector is connected to the pre-amplification and analog-to-digital conversion circuit 2 to convert the optical signal into an electrical signal.

[0007] Specifically, the preamplifier and analog-to-digital converter circuit 2 includes a preamplifier circuit and an analog-to-digital converter. The preamplifier circuit is connected to the photodetector and the analog-to-digital converter, which further filters and amplifies the electrical signal converted by the photodetector. The analog-to-digital converter then converts the analog electrical signal into a digital signal. The analog-to-digital converter is then connected to the digital processing chip, where the software algorithm further processes the digital signal.

[0008] Specifically, the demodulation information classification module 3 receives the digital signal input from the analog-to-digital converter, extracts the digital signal containing self-detection information according to the timing of the self-detection modulation signal application period, and sends it to the self-detection signal demodulation module 6; the remaining digital signal containing angular rate information is sent to the rate information demodulation module 4 for processing.

[0009] Specifically, the rate information demodulation module 4 subtracts and integrates the effective digital signals within the corresponding modulation state period according to the timing of the square wave or four-state modulation signal generated by the modulation signal generation module 8 to obtain the angular rate information; this angular rate information is simultaneously sent to the stepped wave signal generator 5. Specifically, after receiving the angular rate information from the rate information demodulation module 4, the stepped wave signal generation module 5 uses this value as the step height of the stepped wave signal, and generates a step duration of [missing value]. The stepped wave signal is sent to the modulation signal combination module 9, where, This is the fiber optic loop transit time, which is the time it takes for light to travel one full circle within the fiber optic loop.

[0010] Specifically, the self-detection information demodulation module 6, based on the modulation depth generated by the modulation signal generation module 8, is... The self-detection modulation signal timing is obtained by subtracting the effective digital signal within the corresponding modulation state period to obtain self-detection information, which is then sent to the status warning and output module 7.

[0011] Specifically, after receiving the self-detection information from the self-detection information demodulation module 6, the status warning and output module 7 determines whether the gyroscope is working normally according to the preset status alarm threshold, and outputs the gyroscope working status word to realize the gyroscope status self-detection.

[0012] Specifically, the modulation signal generation module 8 generates a normal bias phase, i.e., a modulation depth of , according to the gyroscope closed-loop control principle. Alternatively, a square wave or four-state modulated signal with a modulation depth of [other modulated depths] can be used to improve phase detection sensitivity and achieve rate information demodulation; simultaneously, this square wave or four-state modulated signal can be periodically replaced with a modulation depth of [other modulated depths]. Duration is The self-detection modulation signal is combined to generate a gyroscope modulation signal, which is then sent to the modulation signal combination module 9. The modulation signal combination module 9 is connected to the digital-to-analog converter and subsequent amplifier circuit 10. It superimposes the stepped wave signal and the modulation signal sent by the stepped wave signal generation module 5 and the modulation signal generation module 8, and sends the superimposed signal to the digital-to-analog converter and subsequent amplifier circuit 10.

[0013] Secondly, this application provides a method for achieving rapid self-testing upon power-on over a wide temperature range, characterized in that the method utilizes the aforementioned fiber optic gyroscope capable of achieving rapid self-testing upon power-on over a wide temperature range, and the method includes: Step 1: The modulation signal generation module generates a periodic modulation signal; Step 2: After the modulated signal is superimposed on the stepped wave signal by the modulated signal combination module, it is applied to the integrated optical modulator of the optical path section of the fiber optic gyroscope by the subsequent amplification and digital-to-analog conversion circuit to achieve phase modulation; Step 3: The preamplifier and analog-to-digital converter circuit receives the electrical signal converted by the photodetector in the optical path of the fiber optic gyroscope and sends it to the demodulation information classification module; Step 4: The demodulation information classification module extracts the self-detection interference signal according to the modulation signal application timing, and sends the extracted signal to the self-detection information demodulation module; Step 5: The self-detection information demodulation module demodulates the step height corresponding to the interference step signal. This is the self-detection demodulated signal, which is then sent to the status warning and output module; Step 6: The status warning and output module determines the working status of the gyroscope based on the self-detection demodulation signal value and the preset self-detection threshold, and outputs the status word to the outside world.

[0014] In summary, this invention provides a fiber optic gyroscope and method capable of rapid self-testing upon power-on over a wide temperature range. Without altering the optical path structure or circuit hardware of the fiber optic gyroscope, it achieves rapid self-testing within microseconds after power-on, solely through software algorithm design, unaffected by factors such as saturated or fluctuating optical power output of the photodetector or asynchronous thermal response hysteresis characteristics of gyroscope components. This is of great significance for the health management and long-term reliability of fiber optic gyroscopes. Attached image description: Figure 1 This refers to the normal bias phase modulation signal of the fiber optic gyroscope and the corresponding interference and response signals.

[0015] Figure 2 This invention provides a block diagram of a fiber optic gyroscope capable of rapid self-testing upon power-on over a wide temperature range.

[0016] Figure 3 This is a schematic diagram of the gyroscope's stepped wave signal and modulation signal.

[0017] Figure 4 These are the self-detection interference signal and response signal corresponding to the self-detection modulation signal.

[0018] Figure 5 This is a graph showing the change curve of the demodulation value after the gyroscope is powered on and the setting of the self-detection threshold, established over a wide temperature range.

[0019] The components are: 1-Fiber optic gyroscope optical path, 2-Pre-amplifier and analog-to-digital converter circuit, 3-Demodulation information classification module, 4-Rate information demodulation module, 5-Step wave signal generator, 6-Self-detection information demodulation module, 7-Status warning and output module, 8-Modulation signal generation module, 9-Modulation signal combination module, and 10-Post-amplifier and digital-to-analog converter circuit. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0021] Generally, when the feedback signal provided by the main control circuit of a fiber optic gyroscope keeps the gyroscope's non-reciprocal phase shift near zero, its detection sensitivity is zero. To improve the phase detection sensitivity, the main control circuit of the fiber optic gyroscope typically provides an offset phase, causing the phase detection point to shift to zero. or near other modulation depths, such as Figure 1 As shown, better detection sensitivity and zero-bias performance can be obtained through phase bias modulation technology.

[0022] If the phase offset modulation depth is adjusted to In a fiber optic gyroscope loop, the interference of two beams of light propagating in opposite directions creates dark fringes. Since there is no light signal input at the photodetector, this signal can be used as a reference. The difference is determined by comparing the normal signal output of the photodetector after the fiber optic gyroscope is powered on with... The signal is output under phase modulation for self-testing of the fiber optic gyroscope. If the gyroscope functions normally, regardless of whether the optical power of the gyroscope saturates or fluctuates significantly after power-on in a wide temperature range, it will be consistent with... The signal output difference under phase modulation is always at its maximum value, enabling rapid self-testing upon power-on over a wide temperature range.

[0023] This research focuses on embedded self-testing technology. Without adding optical or electronic components, it designs a modulation and demodulation method to achieve rapid self-testing of the fiber optic gyroscope over a wide temperature range by comparing the response signals of the fiber optic gyroscope under a specific modulation state. This improves the health management capabilities and long-term reliability of the fiber optic gyroscope in system applications.

[0024] This invention provides a fiber optic gyroscope and method that can achieve rapid self-testing upon power-on over a wide temperature range.

[0025] The basic working principle of a fiber optic gyroscope is to detect changes in the intensity of light output from a photodetector to determine the optical path. Phase shift is used to obtain the angular velocity of the light path rotating along its normal direction, based on... The effect is that the intensity of the light signal detected by the photodetector is (1) In the formula The average output light intensity For two beams of light propagating in opposite directions Phase difference.

[0026] As can be seen from the cosine function, its output sensitivity is lowest near zero input. Typically, the main control circuit of a fiber optic gyroscope provides a bias phase to ensure that the two beams of light propagating in opposite directions... Introducing a fixed phase into the phase difference This allows us to obtain the highest sensitivity near zero input. Equation 1 will then transform into... (2) To overcome the insufficient nonlinear performance of open-loop gyroscopes, closed-loop feedback control is generally used to generate an additional feedback phase difference in the optical path system. . Phase difference caused by rotation Equal in magnitude but opposite in sign, resulting in a total phase difference If the light signal intensity is near zero, then the light signal intensity detected by the photodetector is: (3) (4) If the phase offset modulation depth is adjusted to The phase, as can be seen from Equations 3 and 4, (5) When the two beams of light propagating in the forward and reverse directions in the fiber optic gyroscope loop interfere, dark fringes are formed. Since there is no light signal input at the photodetector end, a large step difference will be formed with the normal operating signal.

[0027] by Using the phase modulation response signal as a reference, the normal signal output of the photodetector after the fiber optic gyroscope is powered on is compared with... Phase-modulated signal output enables self-detection of the fiber optic gyroscope's status. If the gyroscope functions correctly, regardless of whether the optical power saturates or fluctuates significantly after power-on in a wide temperature range, it will function as expected. The signal output difference under phase modulation is always at its maximum value, enabling rapid self-testing upon power-on over a wide temperature range.

[0028] Example 1 like Figure 2As shown, this invention provides a fiber optic gyroscope capable of rapid self-testing upon power-on over a wide temperature range, comprising: 1. a fiber optic gyroscope optical path section; 2. a pre-amplifier and analog-to-digital converter circuit; 3. a demodulation information classification module; 4. a rate information demodulation module; 5. a stepped wave signal generator; 6. a self-test information demodulation module; 7. a status warning and output module; 8. a modulation signal generation module; 9. a modulation signal combination module; and 10. a digital-to-analog converter and post-amplifier circuit, wherein: Fiber optic gyroscope optical path section 1 implements the fiber optic gyroscope The effect is the foundation for the basic function realization of the fiber optic gyroscope; the pre-amplifier and analog-to-digital converter circuit 2 amplifies the electrical signal converted by the photodetector and converts the analog electrical signal into a digital signal for use by the demodulation information classification module; the demodulation information classification module 3 divides the pre-amplifier input signal into a rate signal to be demodulated and a self-detection signal to be demodulated according to the software algorithm control timing; the rate signal to be demodulated is sent to the rate information demodulation module 4, which demodulates the rate signal according to the demodulation timing and generates a step signal corresponding to the rate information, which is sent to the step wave signal generation module 5; the self-detection information demodulation module 6 receives the self-detection signal to be demodulated and completes the self-detection information demodulation, and transmits the demodulation result to the status warning and output module 7; the status warning and output module 7 calculates and judges whether the current functional state of the gyroscope is normal according to the self-detection threshold, and completes the gyroscope self-detection and working status output; the modulation signal generation module 8 generates a square wave or four-state modulation signal according to the gyroscope closed-loop control timing, and periodically replaces it with a modulation depth of The self-detection modulation signal; the signals generated by the stepped wave signal generation module 5 and the modulation signal generation module 8 are sent to the modulation signal combination module 9, which digitally superimposes the two signals and sends them to the digital-to-analog converter and subsequent amplifier circuit 10; the subsequent amplifier and digital-to-analog converter circuit 10 performs digital-to-analog conversion on the superimposed combined modulation signal and amplifies the signal, and then outputs it to the integrated optical modulator in the optical path section of the fiber optic gyroscope to realize phase modulation of the fiber optic gyroscope.

[0029] It should be noted that the preamplifier and analog-to-digital converter circuit 2, the digital-to-analog converter and post-amplifier circuit 10, and the digital processing chip constitute the hardware circuit part of the fiber optic gyroscope; the demodulation information classification module 3, the rate information demodulation module 4, the stepped wave signal generator 5, the self-detection information demodulation module 6, the status warning and output module 7, the modulation signal generation module 8, and the modulation signal combination module 9 constitute the software algorithm part of the fiber optic gyroscope, and the software algorithm runs in the digital processing chip.

[0030] Specifically, the optical path section 1 of the fiber optic gyroscope includes a light source, a coupler, a fiber optic ring, an integrated optical modulator, and a photodetector. The coupler is connected to the light source, the integrated optical modulator, and the photodetector. The beam splitting port of the integrated optical modulator is then connected to the fiber optic ring. Light emitted from the light source is split into two beams after passing through the coupler and the integrated optical modulator, which propagate in clockwise and counterclockwise directions respectively into the fiber optic ring, then return via the integrated optical modulator and coupler and enter the photodetector. The electrodes of the integrated optical modulator are connected to the subsequent amplification and digital-to-analog conversion circuit 10, converting the electrical signal into phase modulation of the optical signal. The photodetector is connected to the pre-amplification and analog-to-digital conversion circuit 2, converting the optical signal into an electrical signal.

[0031] Specifically, the preamplifier and analog-to-digital converter circuit 2 includes a preamplifier circuit and an analog-to-digital converter (A / D). The preamplifier circuit is connected to the photodetector and the A / D converter, further filtering and amplifying the electrical signal converted by the photodetector. The A / D converter then converts the analog electrical signal into a digital signal, which is then connected to a digital processing chip for further processing by the software algorithm.

[0032] Specifically, the demodulation information classification module 3 receives the digital signal input from the analog-to-digital converter (A / D), extracts the digital signal containing self-detection information according to the timing of the self-detection modulation signal application period, and sends it to the self-detection signal demodulation module 6; the remaining digital signal containing angular rate information is sent to the rate information demodulation module 4 for processing.

[0033] Specifically, the rate information demodulation module 4, based on the timing of the square wave or four-state modulation signal generated by the modulation signal generation module 8, subtracts and integrates the effective digital signals within the corresponding modulation state period to obtain angular rate information. This angular rate information is simultaneously sent to the stepped wave signal generator 5.

[0034] Specifically, after receiving the angular rate information from the rate information demodulation module 4, the stepped wave signal generation module 5 uses this value as the step height of the stepped wave signal, and generates a step duration of [missing value]. , The step wave signal, which is the time it takes for light to travel through the fiber optic loop once, is sent to the modulation signal combination module 9.

[0035] Specifically, the self-detection information demodulation module 6, based on the modulation depth generated by the modulation signal generation module 8, is... The self-detection modulation signal timing is obtained by subtracting the effective digital signal within the corresponding modulation state period to obtain self-detection information, which is then sent to the status warning and output module 7.

[0036] It should be noted that the self-detection information demodulation method utilizes The photodetector with phase modulation has no light response output step. Subtracting the data signal from the demodulation cycle without self-detection interference signals allows for the calculation of the output signal in the gyroscope. It can acquire detection data within a short time and achieve microsecond-level rapid detection after power-on.

[0037] Specifically, after receiving the self-detection information from the self-detection information demodulation module 6, the status warning and output module 7 determines whether the gyroscope is working normally according to the preset status alarm threshold, and outputs the gyroscope working status word to realize the gyroscope status self-detection.

[0038] It should be noted that by establishing a self-test threshold model for the fiber optic gyroscope after power-on within a wide temperature range, the false alarm rate can be reduced and the self-test reliability of the fiber optic gyroscope can be improved.

[0039] Specifically, the modulation signal generation module 8 generates a normal bias phase, i.e., a modulation depth of , according to the gyroscope closed-loop control principle. Alternatively, a square wave or four-state modulated signal with a modulation depth of [other modulation depths] can be used to improve phase detection sensitivity and achieve rate information demodulation. Simultaneously, this square wave or four-state modulated signal is periodically replaced with a signal having a modulation depth of [other modulation depths]. Duration is The self-detection modulation signal is combined to generate a gyroscope modulation signal, which is then sent to the modulation signal combination module 9.

[0040] It should be noted that, based on Phase modulation, using the dark fringes of fiber loop interference as a reference, can be started over a wide temperature range and is not affected by the saturation output or large fluctuations of the photodetector's optical power, or the asynchronous thermal response hysteresis characteristics of the gyroscope components. By demodulating the self-detection interference signal, the gyroscope can quickly achieve self-detection. The entire implementation process does not require changes to the gyroscope's optical path, circuitry, or other hardware, making it easy to implement and promote.

[0041] It should be noted that the periodic application of a duration of The signal amplitude is The self-detection modulation method generates a self-detection interference dark fringe signal, and through a demodulation method corresponding to the timing of the modulation signal, it can simultaneously achieve periodic long-term monitoring of the gyroscope's operating state.

[0042] Specifically, the modulation signal combination module 9 is connected to the digital-to-analog converter and subsequent amplifier circuit 10, which superimposes the stepped wave signal and modulation signal sent by the stepped wave signal generation module 5 and the modulation signal generation module 8, and sends the superimposed signal to the digital-to-analog converter and subsequent amplifier circuit 10.

[0043] Specifically, the digital-to-analog converter and subsequent amplifier circuit 10 includes a digital-to-analog converter (D / A) and a subsequent amplifier circuit. The D / A converter is connected to the digital processing chip, converting the digital signal processed by the software algorithm in the digital processing chip into a module signal. This module signal is then connected to the subsequent amplifier circuit, which further amplifies the electrical signal to drive the integrated optical modulator.

[0044] Example 2 This application provides a wide-temperature-range fast power-on self-test method, applied to the fiber optic gyroscope provided in the above embodiments, the method comprising: Step 1: Modulation signal generation module 8 generates a periodic modulation signal; Step 11: After the gyroscope is powered on, a periodic self-detection modulation signal is generated at fixed intervals. The duration of the self-detection modulation signal is... , among which, in the first The amplitude of the internal self-detection modulation signal is The second one The amplitude of the internal self-detection modulation signal is .

[0045] Step 12: The self-detection modulation signal is combined with the gyroscope's normal bias phase modulation signal to generate a periodic modulation signal for the gyroscope, such as... Figure 3 The diagram shown is a schematic of a modulation signal according to an embodiment.

[0046] Step 2: After the modulated signal is superimposed on the stepped wave signal by the modulated signal combination module 9, it is applied to the integrated optical modulator of the fiber optic gyroscope optical path section 1 by the subsequent amplification and digital-to-analog conversion circuit 10 to achieve phase modulation; Step 3: The preamplifier and analog-to-digital converter circuit 2 receives the electrical signal converted by the photodetector in the fiber optic gyroscope optical path section 1 and sends it to the demodulation information classification module 3; Step 4: The demodulation information classification module 3 extracts the self-detection interference signal according to the modulation signal application timing, and sends the extracted signal to the self-detection information demodulation module 6; Specifically, such as Figure 4 As shown, due to the periodic depth of the integrated optical modulator is The phase modulation causes interference in the optical path of the fiber optic gyroscope, forming dark fringes. At this time, the photodetector has no optical signal input and generates a periodic interference step digital signal, which is the signal that needs to be extracted and sent to the self-detection information demodulation module 6.

[0047] Step 5: The self-detection information demodulation module 6 demodulates the step height corresponding to the interference step signal. This is the self-detection demodulation signal, which is sent to the status warning and output module 7.

[0048] Specifically, such as Figure 4 As shown, the self-detection signal demodulation process uses the method of subtracting the digital signals in the preceding and following demodulation cycles. When there is no self-detection modulation signal, the amplitude of the input digital signal is [value missing]. When there is a self-detection modulation signal, the amplitude of the digital signal is The step height is obtained by subtracting the digital values ​​of the two signals. This is the self-detection demodulation signal.

[0049] Step 6: The status warning and output module 7 determines the working status of the gyroscope based on the self-detection demodulation signal value and the preset self-detection threshold, and outputs the status word to the outside world.

[0050] Specifically, such as Figure 5 As shown, by establishing self-detection demodulation output models of the fiber optic gyroscope after power-on in a wide temperature range, a preset threshold for gyroscope self-detection is obtained. When the gyroscope functions normally, the demodulated value of the self-detection signal should be greater than this threshold.

[0051] Through the above self-testing method, the gyroscope can finally achieve microsecond-level rapid self-testing after powering on within a wide temperature range.

[0052] In some embodiments, the normal bias phase of the gyroscope generated by the modulation signal generation module 8 can be four-state modulation, square wave modulation, or a hybrid modulation method, and the modulation depth can be [missing information]. Or other modulation depths.

[0053] In some embodiments, the model of the gyroscope's self-detection demodulation value change curve after power-on, established over a wide temperature range, varies depending on the type of gyroscope light source, such as... light source, Different response curves are formed due to factors such as the light source or the temperature control process of the light source.

[0054] In summary, this application provides a wide-temperature-range fast self-test method for power-on based on the aforementioned fiber optic gyroscope. It replaces the normal bias phase modulation of the gyroscope with a modulation depth of [missing information - likely a specific value]. Duration is The self-detection modulation signal is used as a reference, and the loop interference dark fringes generated by the self-detection modulation signal are used to demodulate and obtain the demodulated value of the self-detection response signal. By comparing it with the established self-detection threshold, the working state of the gyroscope is obtained, and microsecond-level self-detection is realized after power-on in a wide temperature range.

[0055] It should be noted that the functional algorithm implementation shown in the above embodiments can be hardware, software, or a combination thereof. When implemented in hardware, it can be, for example, an electronic circuit, an application-specific integrated circuit (ASIC), etc. When implemented in software, the elements of this invention are programs or code segments used to perform the required tasks.

[0056] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should be covered within the protection scope of the present invention.

Claims

1. A fiber optic gyroscope capable of rapid self-testing upon power-on over a wide temperature range, characterized in that... It includes the fiber optic gyroscope optical path section (1), the pre-amplifier and analog-to-digital converter circuit (2), the demodulation information classification module (3), the rate information demodulation module (4), the step wave signal generator (5), the self-detection information demodulation module (6), the status warning and output module (7), the modulation signal generation module (8), the modulation signal combination module (9), and the digital-to-analog converter and post-amplifier circuit (10), wherein: The optical path of the fiber optic gyroscope (1) implements the fiber optic gyroscope Effect; the preamplifier and analog-to-digital converter circuit (2) amplifies the electrical signal converted by the photodetector and converts the analog electrical signal into a digital signal for use by the demodulation information classification module; the demodulation information classification module (3) divides the digital signal into the rate signal to be demodulated and the self-detection signal to be demodulated; the rate signal to be demodulated is sent to the rate information demodulation module (4), which demodulates the rate signal according to the demodulation timing and generates a step signal corresponding to the rate information, which is sent to the step wave signal generation module (5); the self-detection information demodulation module (6) receives the self-detection signal to be demodulated and completes the self-detection information demodulation, and transmits the demodulation result to the status warning and output module (7); the status warning and output module (7) according to The self-detection threshold is calculated and the current functional state of the gyroscope is judged to be normal, and the gyroscope self-detection and working status output are completed. The modulation signal generation module (8) generates a square wave or four-state modulation signal according to the gyroscope closed-loop control timing, and periodically replaces it with a self-detection modulation signal with a modulation depth of ±π. The signals generated by the step wave signal generation module (5) and the modulation signal generation module (8) are sent to the modulation signal combination module (9), which superimposes the two signals into digital quantities and sends them to the digital-to-analog converter and the subsequent amplifier circuit (10). The subsequent amplifier and digital-to-analog converter circuit (10) performs digital-to-analog conversion on the superimposed combined modulation signal and amplifies the signal before outputting it to the integrated optical modulator in the optical path of the fiber optic gyroscope.

2. The fiber optic gyroscope according to claim 1, characterized in that... The optical path of the fiber optic gyroscope (1) includes a light source, a coupler, an optical fiber ring, an integrated optical modulator, and a photodetector. The coupler is connected to the light source, the integrated optical modulator, and the photodetector respectively. The beam splitting port of the integrated optical modulator is then connected to the optical fiber ring. The light emitted from the light source is split into two beams after passing through the coupler and the integrated optical modulator. They enter the optical fiber ring in clockwise and counterclockwise directions respectively, and then return through the integrated optical modulator and the coupler and enter the photodetector. The integrated optical modulator electrode is connected to the post-amplifier and digital-to-analog converter circuit (10) to convert the electrical signal into phase modulation of the optical signal; the photodetector is connected to the pre-amplifier and analog-to-digital converter circuit (2) to convert the optical signal into an electrical signal.

3. The fiber optic gyroscope according to claim 1, characterized in that... The preamplifier and analog-to-digital converter circuit (2) includes a preamplifier circuit and an analog-to-digital converter. The preamplifier circuit is connected to the photodetector and the analog-to-digital converter to further filter and amplify the electrical signal converted by the photodetector. The analog-to-digital converter then converts the analog electrical signal into a digital signal. The analog-to-digital converter is then connected to the digital processing chip, and the software algorithm part further processes the digital signal.

4. The fiber optic gyroscope according to claim 1, characterized in that... The demodulation information classification module (3) receives the digital signal input from the analog-to-digital converter, extracts the digital signal containing self-detection information according to the self-detection modulation signal application period timing, and sends it to the self-detection signal demodulation module (6); and sends the remaining digital signals containing angular rate information to the rate information demodulation module (4) for processing.

5. The fiber optic gyroscope according to claim 1, characterized in that... The rate information demodulation module (4) subtracts and integrates the effective digital signals within the corresponding modulation state period according to the timing of the square wave or four-state modulation signal generated by the modulation signal generation module (8) to obtain the angular rate information; the angular rate information is simultaneously sent to the step wave signal generator (5).

6. The fiber optic gyroscope according to claim 1, characterized in that... The stepped wave signal generation module (5) receives the angular rate information from the rate information demodulation module (4), and uses this value as the step height of the stepped wave signal, generating a step duration of... The stepped wave signal is sent to the modulation signal combination module (9), where, This is the fiber optic loop transit time, which is the time it takes for light to travel one full circle within the fiber optic loop.

7. The fiber optic gyroscope according to claim 1, characterized in that... The self-detection information demodulation module (6) generates a modulation depth of based on the modulation signal generation module (8). The self-detection modulation signal timing is obtained by subtracting the effective digital signal within the corresponding modulation state period to obtain the self-detection information, which is then sent to the status warning and output module (7).

8. The fiber optic gyroscope according to claim 1, characterized in that... After receiving the self-detection information sent by the self-detection information demodulation module (6), the status warning and output module (7) determines whether the gyroscope is working normally according to the preset status alarm threshold and outputs the gyroscope working status word to realize the gyroscope status self-detection.

9. The fiber optic gyroscope according to claim 1, characterized in that... The modulation signal generation module (8) generates a normal bias phase according to the gyroscope closed-loop control principle, that is, the modulation depth is... Alternatively, a square wave or four-state modulated signal with a modulation depth of [other modulated depths] can be used to improve phase detection sensitivity and achieve rate information demodulation; simultaneously, this square wave or four-state modulated signal can be periodically replaced with a modulation depth of [other modulated depths]. Duration is The self-detection modulation signal is combined to generate a gyroscope modulation signal, which is then sent to the modulation signal combination module (9). The modulation signal combination module (9) is connected to the digital-to-analog converter and subsequent amplifier circuit (10). It superimposes the stepped wave signal and modulation signal sent by the stepped wave signal generation module (5) and the modulation signal generation module (8), and sends the superimposed signal to the digital-to-analog converter and subsequent amplifier circuit (10).

10. A method for achieving rapid self-testing upon power-on over a wide temperature range, characterized in that... The method utilizes the fiber optic gyroscope described in any one of claims 1 to 9, which enables rapid self-testing upon power-on over a wide temperature range. The method includes: Step 1: The modulation signal generation module generates a periodic modulation signal; Step 2: After the modulated signal is superimposed on the stepped wave signal by the modulated signal combination module, it is applied to the integrated optical modulator of the optical path section of the fiber optic gyroscope by the subsequent amplification and digital-to-analog conversion circuit to achieve phase modulation; Step 3: The preamplifier and analog-to-digital converter circuit receives the electrical signal converted by the photodetector in the optical path of the fiber optic gyroscope and sends it to the demodulation information classification module; Step 4: The demodulation information classification module extracts the self-detection interference signal according to the modulation signal application timing, and sends the extracted signal to the self-detection information demodulation module; Step 5: The self-detection information demodulation module demodulates the step height corresponding to the interference step signal. This is the self-detection demodulated signal, which is then sent to the status warning and output module; Step 6: The status warning and output module determines the working status of the gyroscope based on the self-detection demodulation signal value and the preset self-detection threshold, and outputs the status word to the outside world.

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