Biphase magnetic mirror offset frequency laser gyroscope system

Abstract

The invention discloses a biphase magnetic mirror offset frequency laser gyroscope system, and belongs to the technical field of precise laser gyroscopes. The two gyroscopes are arranged in parallel, each gyroscope comprises a gyroscope cavity and an alternating-current phototube assembly which is arranged on the gyroscope cavity and used for outputting demodulation, and the alternating-current phototube assemblies output two A / B signals with the phase difference of 90 degrees; two magnetic mirror offset frequency assemblies; the double-phase magnetic field control circuit is used for controlling the two magnetic mirror offset frequency assemblies to generate an orthogonally changing magnetic field so as to generate an offset frequency effect on light; and the signal demodulation systems are respectively used for receiving four paths of A / B signals from the two alternating-current photoelectric tube assemblies, respectively acquiring steering pulse signals of the two gyroscopes according to the A / B signals, and eliminating a lock region by crosswise splicing the steering pulse signals. According to the invention, the problems of test precision and the like of multiple types of laser gyroscopes are solved, the negative influence of the lock region on the laser gyroscope is reduced, and the accuracy and sensitivity of the laser gyroscope are improved.

Description

Technical Field

[0001] A dual-phase magnetic mirror frequency-biased laser gyroscope system belongs to the field of precision laser gyroscope technology. Background Technology

[0002] A laser gyroscope primarily consists of a resonant cavity with various closed loops, such as quadrilaterals and triangles. The gyroscope cavity is equipped with an output mirror, a control mirror, and a bias mirror. A helium-neon laser, propagating in opposite directions through a closed loop formed by the mirrors, interferes with each other when an object moves and experiences angular displacement. This interference allows the angular velocity of the object to be calculated with a precision far exceeding that of a mechanical gyroscope. Because laser gyroscopes have no moving parts, they are easy to maintain, highly reliable, and have a long service life, making them a core component of inertial reference systems.

[0003] Magnetic mirror polarization refers to polarization using a magneto-optical effect equivalent to rotation. There are two types: the transmission magneto-optical effect (Faraday effect) and the reflection Kerr magneto-optical effect. These are insufficient for the stability of a single gyroscope's constant polarization, falling several orders of magnitude short; therefore, alternating polarization is necessary. The advantage of the Faraday effect is its ease of achieving high polarization, exceeding 2000 degrees / second; however, its application to a single gyroscope is complex, requiring a ferromagnetic medium to obtain an alternating magnetized saturated square wave for polarization, resulting in very high transmission loss and rendering it unusable. In principle, electromagnetic oscillation polarization lacks the advantage of mechanical jitter polarization, which automatically eliminates errors caused by asymmetry in the positive and negative half-cycles. Furthermore, it is susceptible to zero drift caused by stray magnetic fields. Only a square wave generated by the magnetization saturation effect can potentially eliminate these errors. While the Kerr magneto-optical effect can only achieve polarization of tens of degrees / second, it requires no additional components; a magnetic mirror can be used directly for reflection. Moreover, its magnetic saturation effect allows it to saturate and form a square wave even in a relatively small magnetic field, resulting in minimal loss.

[0004] In summary, existing laser gyroscopes have the following main drawbacks: the mechanical jitter frequency shifting method has moving parts, resulting in low reliability and poor shock resistance. Furthermore, mechanical vibration can introduce coupling interference and stress, affecting accuracy. On the other hand, the single magnetic mirror frequency shifting method has limited locking effect, is easily affected by external magnetic field interference leading to zero drift, and has a small frequency shifting amount. Summary of the Invention

[0005] The technical problem solved by this invention is to overcome the shortcomings of the prior art, provide a new working mode and demodulation scheme for laser gyroscopes, solve problems such as the testing accuracy of various types of laser gyroscopes, reduce the negative impact of region locking on laser gyroscopes, and improve the accuracy and sensitivity of laser gyroscopes.

[0006] The technical solution of this invention is: a dual-phase magnetic mirror frequency-polarized laser gyroscope system, comprising:

[0007] Two parallel gyroscopes each include a gyroscope cavity and an AC phototube assembly for output demodulation mounted on the gyroscope cavity. The AC phototube assembly outputs two A / B signals with a 90° phase difference.

[0008] Two magnetic mirror frequency shifting components are respectively set on the two gyroscope cavities;

[0009] A two-phase magnetic field control circuit is connected to the two magnetic mirror polarization components and is used to control the two magnetic mirror polarization components to generate orthogonally changing magnetic fields, thereby polarizing the light.

[0010] The signal demodulation system is connected to the two sets of AC phototube assemblies and is used to receive a total of four A / B signals from the two AC phototube assemblies. It also obtains the steering pulse signals of the two gyroscopes based on the A / B signals and eliminates the lock zone by cross-splicing the steering pulse signals.

[0011] Furthermore, the two magnetic mirror frequency-biasing components are respectively positioned diagonally or symmetrically in the two gyroscope cavities.

[0012] Furthermore, the magnetic mirror polarization component includes a magnetoelectric material, and the two-phase magnetic field control circuit applies an alternating control signal to the magnetoelectric material to generate a transverse Kerr magneto-optical effect, thereby achieving optical polarization.

[0013] Furthermore, the two-phase magnetic field control circuit drives the magnetoelectric material to operate in a magnetic saturation state to generate a deflection frequency signal that approximates a square wave.

[0014] Furthermore, the dual-phase magnetic field control circuit includes a phase shifter or a phase shifting module based on a software clock, used to generate two orthogonal control signals to drive the magnetic mirror frequency shifting components on the two gyroscopes respectively.

[0015] Furthermore, a magnetic shielding layer is provided between the two gyroscopes.

[0016] Furthermore, the signal demodulation system implements the lockout function by including:

[0017] The turning time point of each gyroscope is identified based on the four A / B signals.

[0018] Based on the turning time point, the output time period of the two gyroscopes is dynamically divided into a time interval without turning.

[0019] Within the time interval where one gyroscope is pointing, select the non-pointing pulse signal of another gyroscope and count it.

[0020] The pulse signals counted in the non-steering time intervals of the two gyroscopes are spliced ​​together to form the unlocked output.

[0021] Furthermore, it also includes a frequency stabilization control module; the frequency stabilization control module includes:

[0022] A DC phototube disposed on the gyroscope cavity is used to detect the DC light intensity inside the gyroscope cavity;

[0023] The gripping assembly disposed on the gyroscope cavity is used to adjust the physical length of the gyroscope cavity;

[0024] A frequency stabilization circuit is connected to the DC phototube and the card-grabbing assembly respectively. It is used to generate a control signal based on the DC light intensity, drive the card-grabbing assembly to operate, and stabilize the DC light intensity within a preset range near its peak value.

[0025] Furthermore, when the gyroscope cavity is triangular, its three vertices and the midpoints of its three sides are configured in a predetermined manner near the following positions:

[0026] A cathode is set at a preset position near the midpoint of the first side, and an anode is set at a preset position near the midpoint of the second and third sides. The cathode and anode are connected by an internally processed capillary tube, and an inert gas is filled into the gyroscope during the aging stage.

[0027] The card-grabbing component is set at the first vertex position;

[0028] The magnetic mirror frequency-shifting component is positioned at the second vertex location;

[0029] A DC phototube and an AC phototube assembly are simultaneously installed at the third vertex position.

[0030] The advantages of this invention compared to the prior art are:

[0031] (1) This invention forms a combined gyroscope through the action of two magnetic mirrors in two parallel gyroscope cavities, and completely solves the negative impact of mechanical jitter coupling interference by using the non-mechanical jitter of the magnetic mirrors. This provides a basic support for the operation of the two-phase gyroscope. The introduction of shielding box material can ensure that the normal operation of the two-phase combined gyroscope is not affected by external stray magnetic fields and the mutual interference of the two-phase gyroscopes.

[0032] (2) This invention theoretically constructs a dual-phase laser gyroscope based on magnetic mirror frequency shifting, fundamentally overcoming many drawbacks of traditional mechanical dual-phase jittering. This facilitates manufacturing, reduces the difficulty of processing individual magnetic mirrors, and minimizes excessive demands on the size of the locking region. Even though the locking region of a single magnetic mirror cannot surpass the locking region distribution of mechanical jittering, it surpasses the unlocking advantage of traditional mechanical jittering through combined demodulation. This reduces the need for machining, decreases moving parts, and enhances the overall shock resistance of the gyroscope. Closed-loop adjustment using magnetoelectric materials and instrument feedback indicators allows for frequency shifting closed-loop control under different environmental temperatures, ultimately enabling the gyroscope to operate in a more stable state.

[0033] (3) This invention utilizes a static magnetic mirror-biased dual-phase laser gyroscope as its core for demodulation. Ordinary laser gyroscopes typically use two A / B signals with a 90° phase difference for phase detection demodulation. Due to jitter, the static locked region is divided into a dynamic locked region. Currently, the size of the dynamic locked region can only be continuously improved by injecting noise and increasing the jitter amplitude. However, the dual-phase magnetic mirror laser gyroscope can demodulate the relationship between four A / B signals using two gyroscopes with a phase difference in magnetic mirror bias. Then, by cross-splicing the output signals of the two gyroscopes, a region-free gyroscope output is formed, thus realizing the function of a region-free laser gyroscope. Furthermore, this method, through dual-phase magnetic mirror biasing, can easily achieve an equivalent demodulation scheme for gyroscopes with the same jitter frequency, reducing the size of the combined gyroscope, enhancing its mechanical performance, and because there is no mechanical jitter structure, the use of dual-phase optical biasing greatly enhances the stability and vibration resistance of the gyroscope. Attached Figure Description

[0034] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0035] Figure 1 This is a schematic diagram of the demodulated steering pulse of the dual-phase magnetic mirror laser gyroscope of the present invention;

[0036] Figure 2 This is a schematic diagram of the magnetic mirror in the dual-phase magnetic mirror laser gyroscope of the present invention, which can be controlled in a closed loop.

[0037] Figure 3 This is a schematic diagram of the overall structure of the dual-phase magnetic mirror laser gyroscope of the present invention; Detailed Implementation

[0038] To better understand the above technical solutions, the technical solutions of this application will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the embodiments of this application and the specific features in the embodiments are detailed descriptions of the technical solutions of this application, rather than limitations on the technical solutions of this application. In the absence of conflict, the embodiments of this application and the technical features in the embodiments can be combined with each other.

[0039] The following description, in conjunction with the accompanying drawings, provides a more detailed account of a dual-phase laser gyroscope according to an embodiment of this application. Specific implementation methods may include (e.g.) Figure 3 As shown):

[0040] Two parallel gyroscopes each include a gyroscope cavity and an AC phototube assembly for output demodulation mounted on the gyroscope cavity. The AC phototube assembly outputs two A / B signals with a 90° phase difference.

[0041] Two magnetic mirror frequency shifting components are respectively set on the two gyroscope cavities;

[0042] A two-phase magnetic field control circuit is connected to the two magnetic mirror polarization components and is used to control the two magnetic mirror polarization components to generate orthogonally changing magnetic fields, thereby polarizing the light.

[0043] The signal demodulation system is connected to the two sets of AC phototube assemblies and is used to receive a total of four A / B signals from the two AC phototube assemblies. It also obtains the steering pulse signals of the two gyroscopes based on the A / B signals and eliminates the lock zone by cross-splicing the steering pulse signals.

[0044] In the solutions provided in the embodiments of this application, the specific implementation scheme is described using design principles as an example:

[0045] Step 1: Preliminary Construction of Orthogonal Magnetic Mirror Polarization. For the new magnetic mirror polarization: it mainly includes two gyroscope cavities (triangular or quadrilateral, etc.); taking a triangular gyroscope cavity as an example, a cathode is set near the midpoint of one side using indium sealing, and two anodes are set near the midpoints of the other two sides using indium sealing or adhesive bonding. The anode and cathode are connected internally by a mechanically machined capillary tube, and helium-neon gas is filled into the cavity during the gyroscope aging stage; a gripping assembly is set at one vertex of the triangle in each gyroscope cavity, and the gripping assembly is bonded to the gyroscope cavity. The gripping assembly is made of slotted plates, indium steel, and inner and outer ceramic plates bonded together; a magnetic mirror polarization assembly is set at the other vertex of the triangle in each gyroscope cavity, the specific structure of which is as follows. Figure 1As shown, this component is glued to the gyroscope cavity. Each gyroscope cavity has a DC and an AC phototube at the last vertex of the triangle. The DC phototube converts the optical signal into an electrical signal for frequency stabilization, while the AC phototube converts the optical signal into an electrical signal for output demodulation. The two gyroscope cavities are fixed parallel to each other on the upper and lower bases of the gyroscope housing. After fixing, it is best to keep the two magnetic mirrors in symmetrical positions (e.g., one on top and the other on the bottom, at the two ends of the diameter of the circumcircle of the triangle). The working principle of each structure will be further explained in step 2. Figure 1 The schematic diagram of the magnetic mirror is fundamental to realizing a two-phase magnetic mirror, and therefore will be described in more detail. The magnetic mirror in this patent differs from traditional ones in that, to ensure the realization of a two-phase magnetic field (with a fixed phase difference), a fixed-frequency magnetic mirror cannot be made using materials such as garnet. Instead, a circuit is needed to control the magnetoelectric material to generate a controllable magnetic field. To achieve this, on the one hand, the latest magnetoelectric materials are used, and the strength and period of the magnetic field are controlled by the circuit, thereby controlling the magnetic mirror to achieve a regular frequency shift. During the main phase of the jitter period, the material must be kept in a magnetically saturated state to achieve the frequency shifting effect. Due to the magnetic saturation effect, the influence of surrounding stray magnetic fields on the frequency shift is relatively small. After using an alternating frequency shift close to a square wave, the influence of the lock region on the scaling factor and random zero drift is improved. On the other hand, two magnetic mirrors are installed diagonally on two parallel gyroscope cavities. Magnetic shielding materials can be used to isolate the two parallel gyroscope cavities to avoid mutual interference. Furthermore, the magnetoelectric materials of the two magnetic mirrors are controlled by a circuit to generate orthogonally changing biased magnetic fields. These two orthogonally changing biased magnetic fields can bring about magnetic field jitter signals with a 90-degree phase difference and two sets of forward and reverse optical output signals.

[0046] The effect achieved by the features in step one of this invention is to clarify the basic structure of a two-phase magnetic mirror frequency-biased laser gyroscope. Specifically, the two parallel gyroscope cavities form a combined gyroscope due to the action of the two magnetic mirrors, and the negative impact of mechanical jitter coupling interference is completely solved by the non-mechanical jitter of the magnetic mirrors. This provides a basic support for the operation of the two-phase gyroscope. The introduction of the housing shielding material (adding a shielding layer between the two gyroscopes can also reduce mutual interference) ensures that the normal operation of the two-phase combined gyroscope is not affected by external stray magnetic fields or mutual interference between the two-phase gyroscopes.

[0047] Step Two: Model Establishment of the Two-Phase Magnetic Mirror Frequency-Polarizing Laser Gyroscope. The two-phase magnetic mirror frequency-polarizing laser gyroscope aims to achieve static jitter and combined demodulation functions through dual magnetic mirrors. The magnetic mirrors replace the frequency-polarizing effect of the mechanical jitter wheel, ensuring that the two sets of forward and reverse beams have a phase difference that meets the resonance requirements. First, each gyroscope cavity has one cathode and two anodes. During the gyroscope's illumination phase, a voltage above -1000V is applied to the cathode, and a positive voltage is applied to the anodes. The anode voltage is controlled according to the characteristics of the gas being filled, ideally sufficient to break down the gas and form a helium-neon laser. After the gyroscope is illuminated, a stable current needs to be maintained between the cathode and anode, and the current in both arms must be kept consistent to reduce the influence of Langmuir current. Second, by adjusting the magnetic mirrors of the two gyroscope cavities, a 90° phase difference frequency-polarizing function is achieved, allowing each gyroscope cavity to perform its frequency-polarizing function independently. The specific frequency-polarizing principle will be explained below. Then, by controlling the card-grabbing component, the DC light intensity is stabilized near the maximum value of a certain peak to achieve frequency stabilization (a mode sweeping operation is performed when the gyroscope is started to facilitate subsequent stabilization near the maximum light intensity of a certain peak). Finally, by combining and demodulating the AC signals collected by the AC phototubes in each gyroscope cavity, the frequency shifting effect of the gyroscope's two-phase magnetic mirror can be achieved. See step 4 for details of the demodulation. The specific frequency shifting principle of the two-phase magnetic mirror: Unlike previous methods of growing a garnet layer on an antireflective coating and then depositing a total reflection mode, the core magnetic mirror part can have magnetoelectric materials bonded to suitable locations on both sides of the antireflective coating and the total reflection mode. By controlling the magnetoelectric materials through a circuit, a controllable alternating magnetic field is generated between them, still producing a transverse Kerr magneto-optical effect, making the incident surface perpendicular to the magnetic field direction, such as... Figure 1 As shown, unlike the old method of magnetic mirror frequency biasing, this method can adjust the magnetic field strength through a closed loop based on feedback indicators such as sum and frequency. Then, the magnetic field change controlled by the circuit is used to generate an equivalent magnetic field optical biasing signal, while ensuring that the dithering mode changes orthogonally to meet the basic requirements of combined demodulation. This model can be equivalent to two gyroscopes dithering with a 90-degree phase difference, and there is no mechanical dithering interference or magnetic field interference between the two gyroscopes. Therefore, phase detection demodulation of the AB signal can be achieved through orthogonal combination, thereby establishing a two-phase magnetic mirror biasing laser gyroscope model.

[0048] The effect achieved by the second step of this invention is that it theoretically constructs a dual-phase laser gyroscope using a magnetic mirror frequency shifting method, fundamentally overcoming many drawbacks of traditional mechanical dual-phase jittering. This facilitates manufacturing, reduces the difficulty of processing individual magnetic mirrors, and eliminates excessive demands on the size of the locking region. Even though the locking region distribution of a single magnetic mirror cannot match that of mechanical jittering, it surpasses the unlocking advantage of traditional mechanical jittering through combined demodulation. It also reduces the need for machining, decreases moving parts, and enhances the overall shock resistance of the gyroscope. Closed-loop adjustment through magnetoelectric materials and instrument feedback indicators allows for frequency shifting closed-loop adjustment under different environmental temperatures, ultimately enabling the gyroscope to operate in a more stable state.

[0049] Step 3: Circuit Design for Two-Phase Magnetic Field Control. First, the control circuit mainly includes high voltage, dithering, frequency stabilization, and preamplifier components. High voltage is used to illuminate the two gyroscope cavities. A voltage above -1000V is applied to the cathode, and a positive voltage is applied to the anode. The anode voltage is controlled according to the characteristics of the gas being filled; in principle, it should be sufficient to break down the gas and form a helium-neon laser. After the gyroscope is illuminated, a stable current needs to be maintained between the anode and cathode, and the current in both arms must be kept consistent to reduce the influence of Langmuir current. Dithering is mainly used for frequency shifting. Traditionally, this is done mechanically, but this patent mainly utilizes a circuit output of orthogonal sinusoidal or other forms of control voltage to cause the two magnetic mirrors to generate orthogonally changing magnetic fields. This causes the light to be diverted due to the Kerr magneto-optical effect, completing the unlocking operation. Specific circuit control details are provided later. Introduction; Frequency stabilization is mainly used to control the length of the gyroscope cavity. The gyroscope cavity length can be dynamically adjusted using a card-grabbing component. Changes in the gyroscope cavity length cause fluctuations in the DC light intensity. Software or hardware closed-loop demodulation is needed to stabilize the DC light intensity near its maximum value or a smaller value in the locked region. The preamplifier is mainly used to convert the photoelectric signal collected by the DC phototube into a larger voltage signal; a proportional amplifier circuit is generally sufficient. However, the conversion of the photoelectric signal collected by AC light intensity requires two stages of amplification. If necessary, a high-pass filter can be added to remove low-frequency noise. Finally, a hysteresis comparator is added to output a square wave for demodulation, which is explained in step 4. Specifically, for the two-phase magnetic mirror jitter control circuit, by changing the orthogonal magnetic fields of the two magnetic mirrors, the phase of the two sets of light can be controlled to change accordingly. The current development of magnetoelectric materials provides strong support for the fabrication of magnetic mirrors. Simultaneously, technological breakthroughs in magnetoelectric materials provide reliable guarantees for the precise control of magnetic mirrors. Through DDS (Direct Digital Synchronization) and power amplification modules, suitable drive signals can be directly output to control the magnetoelectric materials to generate an alternating magnetic field signal of ideal frequency. This magnetic field signal influences light intensity changes through the transverse Kerr magneto-optical effect, producing a frequency shift. Simultaneously, the fixed phase difference of the frequency shift guides two sets of forward and reverse light intensities to produce phase difference changes, and the magnitude of the frequency shift can be controlled by the strength of the magnetic field, thus achieving closed-loop control of the jitter frequency shift. A phase shifter, i.e., an all-pass filter, can directly shift the phase of the control signal or perform phase shifting operations through software clock control, ultimately achieving a magnetic mirror control signal with orthogonal periodic variations.

[0050] Step 4: Design a four-channel A / B signal demodulation system with orthogonal magnetic mirror frequency offset to achieve lock-out functionality. Specifically, the demodulation principle is similar to that of a mechanical biphasic gyroscope.

[0051] A four-channel A / B signal demodulation system with orthogonal magnetic mirror frequency offset is used. Two A / B signals are AC photoelectric outputs from the upper gyroscope, and the other two are AC photoelectric outputs from the lower gyroscope. The upper and lower gyroscopes can obtain overlock steering information separately using traditional demodulation methods. Therefore, the time periods T1 and T2 of non-overlock steering from the upper and lower gyroscopes can be extracted, such as... Figure 2As shown, after the outputs are combined, the combined outputs are demodulated in a way similar to that of a single gyroscope in the traditional way, and finally the lock-out function is achieved by splicing.

[0052] Since four-channel A / B signal demodulation is used, a high-frequency clock can be used to first perform logic trigger delays and calculations on gyroscope cavities A and B respectively, and then perform phase detection and direction determination operations. Based on the results of phase detection and direction determination, the turning positions and timings of the two jittering wheels can be obtained. As is well known, when the jittering direction of the gyroscope cavity changes, the A / B signals quickly undergo phase changes and enter / exit the lock zone. During phase transitions, the turning position can be determined by using a phase detector or other circuits to output corresponding digital pulses. Then, using the midpoint between the two timing points as a time reference point, and combining this with the midpoint of the two gyroscopes' turning points, the pulse counting time range for the two boundary points can be defined as T1, and the pulse counting time range for the next two boundary points as T2. Within time range T1, pulses from a non-directional gyroscope are selected for counting; similarly, pulses from another non-directional gyroscope are selected for counting within time range T2. Dynamically splicing T1 and T2 yields a pulse output unaffected by the lock-in zone and reduces the sensitivity drop caused by the gyroscope's over-lock zone. It is particularly important to note that near the pulse capture point, the software needs to confirm the pulse count within ±90° of the last pulse to ensure that the A / B signals of each gyroscope appear in pairs at the capture point. Even in rare cases where a single counted pulse may deviate, this error will be randomly canceled out during long-term, multi-cycle sampling and analysis. Furthermore, a very small error at a single instantaneous pulse point will not fatally affect the overall output and accuracy. The direction of jitter can be distinguished based on the rotation phase change, facilitating the separate demodulation of forward and reverse rotation pulses. Following traditional demodulation methods, the cw or ccw output signals from multiple sets of time range T1 from one gyroscope are combined with the cw′ or ccw′ output signals from multiple sets of time range T2 from the other gyroscope. These are then concatenated to obtain cwa and ccwa, followed by pulse number difference frequency calculation. Finally, data processing and debouncing filtering are performed based on the frequency doubling characteristics. The output results are then uploaded to the software interface to obtain information such as accuracy and average output value. When an external rotation speed is applied, the identified lock zone turning position may shift, leading to dynamic adjustments in the magnitudes of T1 and T2. However, this does not change the demodulation method. Of course, if the rotation speed is fast enough, it can approximate a lock-free state, at which point the two time regions merge into one, similar to single-gyroscope demodulation.

[0053] The calculation accuracy can eliminate the negative impact of over-locking regions, while improving sensitivity and accuracy to a certain extent. The sum-frequency signals are represented by cw and ccw using traditional software calculation methods to characterize the jitter intensity of gyroscope cavity A, and cw′ and ccw′ to characterize the jitter intensity of gyroscope cavity B. This aims to keep the jitter intensity of the two gyroscopes as close as possible to ensure the accuracy and adaptability of the splicing calculation results from different time ranges during demodulation.

[0054] The effect achieved by steps three and four of this invention is the core demodulation step of a static magnetic mirror-biased dual-phase laser gyroscope. Ordinary laser gyroscopes typically use two A / B signals with a 90° phase difference for phase detection demodulation. Due to jitter-induced speed reduction and commutation, the static locked region is divided into a dynamic locked region. Currently, the size of the dynamic locked region can only be continuously improved by injecting noise and increasing the jitter amplitude. However, the dual-phase magnetic mirror laser gyroscope can demodulate the relationship between four A / B signals using two gyroscopes with a phase difference due to magnetic mirror bias. Then, by cross-splicing the output signals of the two gyroscopes, a region-free gyroscope output is formed, thus realizing the function of a region-free laser gyroscope. Furthermore, this method, through dual-phase magnetic mirror biasing, can easily achieve an equivalent demodulation scheme for gyroscopes with the same jitter frequency, reducing the size of the combined gyroscope, enhancing its mechanical performance, and because there is no mechanical jitter structure, the use of dual-phase optical biasing greatly enhances the stability and vibration resistance of the gyroscope.

[0055] For optical dual-phase laser gyroscopes, this invention offers greater operability and reduces the potential negative impacts of mechanical methods. Building upon dual-phase demodulation, it addresses the issues of high stress and significant efficiency variations at high and low temperatures caused by mechanical jitter structures by focusing on the gyroscope cavity itself. This reduces the negative impact of the lock zone on the laser gyroscope, improving its accuracy and stability. Furthermore, this approach integrates the working inertia combination with the backup inertia combination, significantly reducing size, weight, and cost. In addition to improving accuracy through dual-phase jitter demodulation, the invention fundamentally eliminates the difficulties in manufacturing dual-phase mechanical jitter gyroscopes by using dual magnetic mirrors, reducing structural complexity. This results in a more lightweight and simpler way to achieve the basic functions of a dual-phase laser gyroscope, improving overall product performance and stability.

[0056] The “A / B signal” mentioned in this article is a general term in this technical field, specifically referring to two orthogonal digital pulse signals with a 90° phase difference output by an AC phototube assembly, used to identify the direction of rotation and subdivide the pulse.

[0057] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

[0058] The contents not described in detail in this specification are common knowledge to those skilled in the art.

Claims

1. A dual-phase magnetic mirror frequency-polarized laser gyroscope system, characterized in that, include: Two parallel gyroscopes each include a gyroscope cavity and an AC phototube assembly for output demodulation mounted on the gyroscope cavity. The AC phototube assembly outputs two A / B signals with a 90° phase difference. Two magnetic mirror frequency shifting components are respectively set on the two gyroscope cavities; A two-phase magnetic field control circuit is connected to the two magnetic mirror polarization components and is used to control the two magnetic mirror polarization components to generate orthogonally changing magnetic fields, thereby polarizing the light. The signal demodulation system is connected to the two sets of AC phototube assemblies and is used to receive a total of four A / B signals from the two AC phototube assemblies. It also obtains the steering pulse signals of the two gyroscopes based on the A / B signals and eliminates the lock zone by cross-splicing the steering pulse signals.

2. The dual-phase magnetic mirror polarized laser gyroscope system according to claim 1, characterized in that, The two magnetic mirror frequency shifting components are respectively located at diagonal or symmetrical positions in the two gyroscope cavities.

3. The dual-phase magnetic mirror frequency-polarizing laser gyroscope system according to claim 1, characterized in that, The magnetic mirror polarization component includes a magnetoelectric material, and the two-phase magnetic field control circuit applies an alternating control signal to the magnetoelectric material to generate a transverse Kerr magneto-optical effect, thereby achieving optical polarization.

4. A dual-phase magnetic mirror polarized laser gyroscope system according to claim 4, characterized in that, The dual-phase magnetic field control circuit drives the magnetoelectric material to operate in a magnetic saturation state to generate a deflection frequency signal that approximates a square wave.

5. A dual-phase magnetic mirror polarized laser gyroscope system according to claim 1, characterized in that, The dual-phase magnetic field control circuit includes a phase shifter or a phase shifting module based on a software clock, used to generate two orthogonal control signals to drive the magnetic mirror frequency shifting components on the two gyroscopes respectively.

6. The dual-phase magnetic mirror frequency-polarizing laser gyroscope system according to claim 1, characterized in that, A magnetic shielding layer is provided between the two gyroscopes.

7. A dual-phase magnetic mirror polarized laser gyroscope system according to claim 1, characterized in that, The signal demodulation system implements the lockout function as follows: The turning time point of each gyroscope is identified based on the four A / B signals. Based on the turning time point, the output time period of the two gyroscopes is dynamically divided into a time interval without turning. Within the time interval where one gyroscope is pointing, select the non-pointing pulse signal of another gyroscope and count it. The pulse signals counted in the non-steering time intervals of the two gyroscopes are spliced ​​together to form the unlocked output.

8. A dual-phase magnetic mirror polarized laser gyroscope system according to claim 1, characterized in that, It also includes a frequency stabilization control module; the frequency stabilization control module includes: A DC phototube disposed on the gyroscope cavity is used to detect the DC light intensity inside the gyroscope cavity; The gripping assembly disposed on the gyroscope cavity is used to adjust the physical length of the gyroscope cavity; A frequency stabilization circuit is connected to the DC phototube and the card-grabbing assembly respectively. It is used to generate a control signal based on the DC light intensity, drive the card-grabbing assembly to operate, and stabilize the DC light intensity within a preset range near its peak value.

9. A dual-phase magnetic mirror frequency-biased laser gyroscope system according to claim 9, characterized in that, When the gyroscope cavity is triangular, its three vertices and the midpoints of its three sides are configured in the following manner at preset proximity positions: A cathode is set at a preset position near the midpoint of the first side, and an anode is set at a preset position near the midpoint of the second and third sides. The cathode and anode are connected by an internally processed capillary tube, and an inert gas is filled into the gyroscope during the aging stage. The card-grabbing component is set at the first vertex position; The magnetic mirror frequency-shifting component is positioned at the second vertex location; A DC phototube and an AC phototube assembly are simultaneously installed at the third vertex position.

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