Silicon photon gyroscope with current modulation and intensity noise compensation functions

Abstract

The invention provides a silicon photon gyroscope with current modulation and intensity noise compensation functions. The silicon photon gyroscope comprises a silicon photon chip and a special integrated circuit, a silicon photon chip integrating a light source, a detector, a coupler and an on-chip ring is adopted, a traditional LN optical phase modulator is not adopted to achieve signal modulation, square wave signal modulation is carried out on a driving current end of a laser, and due to the fact that the laser has a large modulation bandwidth, the requirement for high-rotating-speed application of the silicon photon gyroscope can be met; the design end of the optical chip is smaller in size and lower in cost; an intensity noise compensation function is integrated in the ASIC circuit, intensity noise introduced by current modulation and external factor changes of the single-chip silicon photon gyroscope can be effectively suppressed, the precision of the silicon photon gyroscope is improved, and the ASIC circuit has the technical advantages of small size, low cost and simple production.

Description

Technical Field

[0001] This invention relates to the field of optical sensing technology, and more particularly to a silicon photonic gyroscope with current modulation and intensity noise compensation function. Background Technology

[0002] Fiber optic gyroscopes possess outstanding advantages such as high precision, all-solid-state construction, and flexible structure. They have already been developed into a series of products and have become the preferred inertial measurement element for inertial navigation systems of various precision levels. With the deepening of applications, there is an urgent need for fiber optic gyroscopes to possess advantages such as miniaturization, low cost, and high reliability. Domestic and international research institutions have achieved these goals based on device miniaturization and system micro-assembly methods. However, miniaturized optoelectronic devices face disadvantages such as high cost and poor reliability, and micro-assembly schemes have limited impact on reducing the size of fiber optic gyroscopes. The miniaturization and low-cost development of fiber optic gyroscopes has encountered a bottleneck. In recent years, with the rapid development of integrated optics and micro / nano fabrication technologies, integrating multiple active and passive optical devices on a single silicon photonic chip has become possible and widely applied in the communication field. This provides a new approach for the integration and miniaturization of fiber optic gyroscopes: combining the advantages of miniaturized and easily mass-produced integrated optical chips with the high precision of fiber optic gyroscopes, silicon photonic gyroscopes are gradually becoming a cutting-edge research hotspot for next-generation optical gyroscopes internationally.

[0003] The integration of multiple materials presents material compatibility challenges. For example, active materials used in light source fabrication have good hybrid integration potential with PLC materials used in couplers and on-chip rings, and Ge materials used in detector fabrication. However, effective integration of active materials with LN materials used in optical phase modulators is difficult, hindering the integrated development of multiple devices and becoming a bottleneck limiting the improvement of integration density. Furthermore, the integration of optical paths inevitably leads to chip heating and high intensity noise, severely restricting the performance improvement of silicon photonic gyroscopes. Therefore, there is an urgent need for a silicon photonic gyroscope technology solution that does not integrate an LN phase modulator and possesses intensity noise compensation capabilities. Summary of the Invention

[0004] This invention provides a silicon photonic gyroscope with current modulation and intensity noise compensation, which can solve the technical problem.

[0005] According to one aspect of the present invention, a silicon photonic gyroscope with current modulation and intensity noise compensation function is provided, comprising a silicon photonic chip and an application-specific integrated circuit (ASIC circuit);

[0006] The silicon photonic chip includes a laser, a Y-branch, a first coupler, a second coupler, a third coupler, a waveguide resonant cavity, a first detector, and a second detector. The laser emits light to the Y-branch under the control of a temperature control signal and a square wave current signal. The Y-branch splits the received laser light into two linearly polarized beams of equal power. One beam enters the third coupler via the first coupler, and the other beam enters the third coupler via the second coupler. The third coupler outputs the two linearly polarized beams to the waveguide resonant cavity. Polarized light propagates in the waveguide resonant cavity in clockwise and counterclockwise directions, respectively. After propagating several times within the waveguide resonant cavity, the two linearly polarized beams enter the third coupler to form multi-beam interference. The clockwise linearly polarized light enters the first detector via the first coupler, and the counterclockwise linearly polarized light enters the second detector via the second coupler. The first detector is used to obtain a clockwise resonant signal based on the clockwise linearly polarized light and outputs it to the dedicated integrated circuit. The second detector is used to obtain a counterclockwise resonant signal based on the counterclockwise linearly polarized light and outputs it to the dedicated integrated circuit.

[0007] The dedicated integrated circuit is used to determine whether the counterclockwise resonant signal is within the resonance valley. If the counterclockwise resonant signal is not within the resonance valley, the temperature control signal is adjusted to perform a linear scan of the temperature control segment of the laser until the counterclockwise resonant signal enters the resonance valley. If the counterclockwise resonant signal is within the resonance valley, the clockwise and counterclockwise resonant signals are demodulated simultaneously to obtain the frequency difference between the laser frequency and the clockwise resonant frequency, and the frequency difference between the laser frequency and the counterclockwise resonant frequency. The differential-mode component and common-mode component of the frequency difference between the laser frequency and the clockwise resonant frequency, and the common-mode component are obtained. It is also used to determine whether the differential-mode component is within the resonance valley. If the differential-mode component is 0, the common-mode component is used as the final output signal of the gyroscope. If the differential-mode component is greater than 0, the square wave current signal is down-tuned, and the gyroscope output error caused by intensity change is obtained based on the differential-mode component and the common-mode component. The common-mode component is compensated based on the gyroscope output error caused by intensity change, and the compensated common-mode component is used as the final output signal of the gyroscope. If the differential-mode component is less than 0, the square wave current signal is up-tuned, and the gyroscope output error caused by intensity change is obtained based on the differential-mode component and the common-mode component. The common-mode component is compensated based on the gyroscope output error caused by intensity change, and the compensated common-mode component is used as the final output signal of the gyroscope.

[0008] Preferably, the gyroscope output error caused by intensity change is obtained by the following formula:

[0009]

[0010] In the formula, ΔΩ biasK represents the gyroscope output error caused by intensity variation. im S is the equivalent zero-bias coefficient caused by strength imbalance. dif For the differential mode component, S com This is the common-mode component.

[0011] Preferably, the compensated common-mode component is obtained by the following formula:

[0012] Ω out =GS com +ΔΩ bias

[0013] In the formula, Ω out The common-mode component is the compensated component, and G is the system scaling factor.

[0014] According to another aspect of the present invention, a compensation method for a silicon photonic gyroscope with current modulation and intensity noise compensation function is provided, the compensation method employing any of the aforementioned silicon photonic gyroscopes for compensation, the method comprising:

[0015] The application-specific integrated circuit (ASIC) determines whether the counterclockwise resonant signal is within the resonance valley. If the counterclockwise resonant signal is not within the resonance valley, the temperature control signal is adjusted to perform a linear scan of the temperature control segment of the laser until the counterclockwise resonant signal enters the resonance valley. If the counterclockwise resonant signal is within the resonance valley, the clockwise and counterclockwise resonant signals are demodulated simultaneously to obtain the frequency difference between the laser frequency and the clockwise resonant frequency, and the frequency difference between the laser frequency and the counterclockwise resonant frequency.

[0016] The application-specific integrated circuit (ASIC) acquires the differential-mode component and common-mode component of the frequency difference between the laser frequency and the clockwise resonant frequency, and the frequency difference between the laser frequency and the counterclockwise resonant frequency.

[0017] The application-specific integrated circuit (ASIC) determines whether the differential-mode component is 0. If the differential-mode component is 0, the common-mode component is used as the final output signal of the gyroscope. If the differential-mode component is greater than 0, the square wave current signal is down-tuned, and the gyroscope output error caused by the intensity change is obtained based on the differential-mode component and the common-mode component. The common-mode component is then compensated based on the gyroscope output error caused by the intensity change, and the compensated common-mode component is used as the final output signal of the gyroscope. If the differential-mode component is less than 0, the square wave current signal is up-tuned, and the gyroscope output error caused by the intensity change is obtained based on the differential-mode component and the common-mode component. The common-mode component is then compensated based on the gyroscope output error caused by the intensity change, and the compensated common-mode component is used as the final output signal of the gyroscope.

[0018] The technical solution of this invention has the following advantages: First, it uses a silicon photonic chip that integrates a light source, detector, coupler, and on-chip loop. Instead of using a traditional LN optical phase modulator for signal modulation, it modulates the drive current terminal of the laser with a square wave signal. Since the laser has a large modulation bandwidth, it can meet the high-speed application of silicon photonic gyroscopes. From the design perspective of the optical chip, it also has a smaller size and lower cost. Second, it integrates intensity noise compensation function in ASIC circuit, which can effectively suppress the intensity noise introduced by the current modulation of monolithic silicon photonic gyroscope and changes in external factors, thereby improving the accuracy of silicon photonic gyroscopes. This invention has the technical advantages of small size, low cost, and simple production. Attached Figure Description

[0019] The accompanying drawings, which form part of this specification, are provided to further illustrate embodiments of the invention and, together with the textual description, explain the principles of the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0020] Figure 1 A schematic diagram of a silicon photonic gyroscope with current modulation and intensity noise compensation function according to an embodiment of the present invention is shown.

[0021] Figure 2 A graph showing the relationship between gyroscope sensitivity and modulation current amplitude according to an embodiment of the present invention is shown.

[0022] Figure 3 A schematic diagram of the square wave current modulation and tuning range provided according to an embodiment of the present invention is shown;

[0023] Figure 4 A closed-loop workflow diagram of a silicon photonic gyroscope according to an embodiment of the present invention is shown. Detailed Implementation

[0024] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0026] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0027] like Figure 1 As shown, the present invention provides a silicon photonic gyroscope with current modulation and intensity noise compensation function, including a silicon photonic chip and an ASIC circuit;

[0028] The silicon photonic chip includes a laser, a Y-branch, a first coupler, a second coupler, a third coupler, a waveguide resonant cavity, a first detector, and a second detector. The laser emits light to the Y-branch under the control of a temperature control signal and a square wave current signal. The Y-branch splits the received laser light into two linearly polarized beams of equal power. One beam enters the third coupler via the first coupler, and the other beam enters the third coupler via the second coupler. The third coupler outputs the two linearly polarized beams to the waveguide resonant cavity. Polarized light propagates in the waveguide resonant cavity in clockwise and counterclockwise directions, respectively. After propagating several times within the waveguide resonant cavity, the two linearly polarized beams enter the third coupler to form multi-beam interference. The clockwise linearly polarized light enters the first detector via the first coupler, and the counterclockwise linearly polarized light enters the second detector via the second coupler. The first detector is used to obtain a clockwise resonant signal based on the clockwise linearly polarized light and outputs it to the ASIC circuit. The second detector is used to obtain a counterclockwise resonant signal based on the counterclockwise linearly polarized light and outputs it to the ASIC circuit.

[0029] The ASIC circuit is used to determine whether the counterclockwise resonant signal is within the resonance valley. If the counterclockwise resonant signal is not within the resonance valley, the temperature control signal is adjusted to perform a linear scan of the temperature control segment of the laser until the counterclockwise resonant signal enters the resonance valley. If the counterclockwise resonant signal is within the resonance valley, the clockwise and counterclockwise resonant signals are demodulated simultaneously to obtain the frequency difference between the laser frequency and the clockwise resonant frequency, and the frequency difference between the laser frequency and the counterclockwise resonant frequency. The differential-mode component and common-mode component of the frequency difference between the laser frequency and the clockwise resonant frequency and the frequency difference between the laser frequency and the counterclockwise resonant frequency are obtained. It is also used to determine whether the differential-mode component is within the resonance valley. If the differential-mode component is 0, the common-mode component is used as the final output signal of the gyroscope. If the differential-mode component is greater than 0, the square wave current signal is down-tuned, and the gyroscope output error caused by intensity change is obtained based on the differential-mode component and the common-mode component. The common-mode component is compensated based on the gyroscope output error caused by intensity change, and the compensated common-mode component is used as the final output signal of the gyroscope. If the differential-mode component is less than 0, the square wave current signal is up-tuned, and the gyroscope output error caused by intensity change is obtained based on the differential-mode component and the common-mode component. The common-mode component is compensated based on the gyroscope output error caused by intensity change, and the compensated common-mode component is used as the final output signal of the gyroscope.

[0030] In this invention, the ASIC circuit integrates a square wave current signal with a certain bias and tunable, which has three functions: 1. To provide a square wave current signal (i.e., bias current) to realize constant drive current control of the laser; 2. To realize current modulation of a certain frequency and amplitude, thereby replacing the phase modulation method in the traditional silicon photonic gyroscope; 3. To adjust the bias of the square wave current in real time according to the closed-loop demodulation result, so as to realize the closed-loop control of the laser center frequency on the resonant frequency of the waveguide resonant cavity, laying the foundation for speed detection.

[0031] The design parameters of the square wave current signal mainly include frequency, tuning range, and amplitude, which are prerequisites for determining the gyroscope's sensitivity and system stability. The methods for establishing these parameters are as follows:

[0032] (1) First, the frequency of the square wave current signal needs to be determined: The frequency of the square wave current signal is mainly determined by the tuning bandwidth of the narrow linewidth laser. The tuning frequency of a frequency-tunable narrow linewidth laser can usually reach hundreds of kHz. Since the square wave current signal is a multiple harmonic component of the tuning frequency, the modulation frequency cannot be too high in order to ensure the tuning bandwidth, and it usually needs to be less than 100 kHz. In addition, the relative intensity noise of the narrow linewidth laser is low above 10 kHz, and the noise amplitude is inversely proportional to the frequency. Therefore, in order to achieve effective suppression of relative intensity noise, the frequency of the square wave current signal is set to 50 kHz.

[0033] (2) Secondly, it is necessary to establish the tuning range of the square wave current signal: Since the theoretical optimal tuning range of the traditional narrow linewidth laser is 100-120mA, we set the bias voltage to be exactly in the middle of the linear tuning range, i.e., 110mA; Since the current tuning range of the narrow linewidth laser is usually around 50MHz / mA, 20mA current can achieve a tuning range of 1GHz. Therefore, within the optimal tuning range, it is possible to match the maximum free spectral width of multiple waveguide resonators, thereby ensuring the tuning and control of the resonant frequency of the waveguide resonator by the center frequency of the laser on the silicon photonic chip. Therefore, the tuning range is established as 110±10mA.

[0034] (3) Finally, it is necessary to determine the amplitude of the square wave current signal: the amplitude of the square wave current signal reflects the frequency tuning magnitude. Under different frequency tuning values, the optimal tuning amplitude should be selected to ensure that the silicon photonic gyroscope has the best sensitivity.

[0035] A 50kHz square wave current signal is applied to the drive current terminal of the laser as the frequency modulation signal, and the amplitude of the modulation current is set to i. squ You can get something like Figure 2 The curve showing the relationship between gyroscope sensitivity and modulation current amplitude reveals an optimal modulation amplitude at which the gyroscope exhibits maximum sensitivity. This current amplitude is calculated to be 0.25 mA.

[0036] Therefore, the frequency of the square wave current was set at 50kHz, the amplitude at 0.25mA, the bias voltage at 110mA, and the tuning range at 110±10mA. Figure 3 As shown, it is specifically divided into three sections: the upper tuning section, the lower tuning section, and the modulation section, taking into account both modulation and tuning functions.

[0037] like Figure 4 The diagram shows a compensation method for a silicon photonic gyroscope with current modulation and intensity noise compensation, which specifically includes the following steps:

[0038] (1) When the ASIC circuit is powered on, the circuit first performs a reset detection. If the reset signal is high, the circuit board is initialized; if the reset signal is low, the square wave current signal is set according to the established square wave current frequency, amplitude and bias voltage and applied to the laser current pin of the silicon photonic chip.

[0039] (2) The valley entry is determined based on the counterclockwise resonant signal (CCW) output signal. The specific determination method is based on the comparison voltage. If it is low, it means that it is outside the valley. At this time, the temperature control signal in the ASIC circuit linearly scans the temperature control section of the laser to make it enter the resonant valley.

[0040] (3) Once the resonant valley is detected, the CCW and clockwise resonant signal (CW) output signals are demodulated synchronously. Then, the differential mode components of CCW and CW are used as the input control of the current closed-loop control signal, while the common mode components of CCW and CW are used as the gyroscope output signal (before square wave intensity compensation).

[0041] (4) Determine whether the differential mode component is 0. If it is 0, it means that the laser center frequency has been steadily locked to the resonant frequency of the waveguide resonant cavity. At this time, the square wave current maintains its current value. If it is not 0, it means that the square wave current needs to be tuned.

[0042] (5) Determine the positive or negative value of the differential mode component. If the value is greater than 0, perform square wave current tuning, mainly operating in... Figure 3 If the lower tuning region shown is determined to be less than 0, then the square wave current is tuned upwards, mainly operating in... Figure 3 The upper tuning region is shown; during this process, the gyroscope output error caused by intensity changes is calculated using the following formula:

[0043]

[0044] In the formula, ΔΩ bias The gyroscope output error (unit: ° / h) caused by intensity variation is determined by device asymmetry, coupling error, etc., and can be obtained through calibration; K im S is the equivalent zero-bias coefficient caused by strength imbalance. dif For the differential mode component (used for frequency locking), S com This is the common-mode component (which is the original gyroscope output including intensity error);

[0045] (6) Through multiple closed-loop control, the center frequency of the laser is steadily locked to the resonant frequency of the waveguide resonant cavity, and the square wave current no longer changes and remains at its current value.

[0046] (7) Perform intensity compensation in the square wave intensity compensation module to compensate for the gyroscope output error caused by the change in square wave current, and obtain the compensated gyroscope output Ω. out As shown in the following formula:

[0047] Ω out =GS com +ΔΩ bias

[0048] In the formula, Ω out G is the compensated common-mode component (which is the gyroscope output without intensity error), and G is the system scaling factor (obtained from the room-temperature calibration of the silicon photonic gyroscope).

[0049] In summary, this invention provides a silicon photonic gyroscope with current modulation and intensity noise compensation, which has the following advantages: First, it uses a silicon photonic chip that integrates a light source, detector, coupler, and on-chip loop. Instead of using a traditional LN optical phase modulator for signal modulation, it modulates the drive current terminal of the laser with a square wave signal. Since the laser has a large modulation bandwidth, it can meet the high-speed application requirements of the silicon photonic gyroscope. From the design perspective of the optical chip, it also has a smaller size and lower cost. Second, the intensity noise compensation function is integrated into the ASIC circuit, which can effectively suppress the intensity noise introduced by the current modulation of the monolithic silicon photonic gyroscope and changes in external factors, thereby improving the accuracy of the silicon photonic gyroscope. This invention has the technical advantages of small size, low cost, and simple production.

[0050] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0051] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0052] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A silicon photonic gyroscope with current modulation and intensity noise compensation function, characterized in that, Including silicon photonics chips and application-specific integrated circuits; The silicon photonic chip includes a laser, a Y-branch, a first coupler, a second coupler, a third coupler, a waveguide resonant cavity, a first detector, and a second detector. The laser is used to emit laser light to the Y-branch under the control of a temperature control signal and a square wave current signal. The Y-branch is used to split the received laser light to obtain two linearly polarized beams of equal power. One linearly polarized beam enters the third coupler via the first coupler, and the other linearly polarized beam enters the third coupler via the second coupler. The third coupler is used to output two linearly polarized beams to the waveguide resonant cavity. The two linearly polarized beams propagate in the waveguide resonant cavity in clockwise and counterclockwise directions, respectively. After propagating several times in the waveguide resonant cavity, the two linearly polarized beams enter the third coupler to form multi-beam interference. The clockwise linearly polarized beam enters the first detector via the first coupler, and the counterclockwise linearly polarized beam enters the second detector via the second coupler. The first detector is used to obtain a clockwise resonant signal based on the clockwise linearly polarized beam and output it to the dedicated integrated circuit. The second detector is used to obtain a counterclockwise resonant signal based on the counterclockwise linearly polarized beam and output it to the dedicated integrated circuit. The dedicated integrated circuit is used to determine whether the counterclockwise resonant signal is within the resonance valley. If the counterclockwise resonant signal is not within the resonance valley, the temperature control signal is adjusted to perform a linear scan of the temperature control segment of the laser until the counterclockwise resonant signal enters the resonance valley. If the counterclockwise resonant signal is within the resonance valley, the clockwise and counterclockwise resonant signals are demodulated simultaneously to obtain the frequency difference between the laser frequency and the clockwise resonant frequency, and the frequency difference between the laser frequency and the counterclockwise resonant frequency. The differential-mode component and common-mode component of the frequency difference between the laser frequency and the clockwise resonant frequency, and the frequency difference between the laser frequency and the counterclockwise resonant frequency are obtained. It is also used to determine whether the differential mode component is 0. If the differential mode component is 0, the common mode component is used as the final output signal of the gyroscope. If the differential mode component is greater than 0, the square wave current signal is down-tuned, and the gyroscope output error caused by the intensity change is obtained based on the differential mode component and the common mode component. The common mode component is compensated based on the gyroscope output error caused by the intensity change, and the compensated common mode component is used as the final output signal of the gyroscope. If the differential-mode component is less than 0, the square wave current signal is up-tuned, and the gyroscope output error caused by the intensity change is obtained based on the differential-mode component and the common-mode component. The common-mode component is compensated based on the gyroscope output error caused by the intensity change, and the compensated common-mode component is used as the final output signal of the gyroscope.

2. The method according to claim 1, characterized in that, The gyroscope output error caused by intensity variation is obtained using the following formula: In the formula, ΔΩ bias K represents the gyroscope output error caused by intensity variation. im S is the equivalent zero-bias coefficient caused by strength imbalance. dif For the differential mode component, S com This is the common-mode component.

3. The method according to claim 1, characterized in that, The compensated common-mode component is obtained using the following formula: Oh out =GS com +GIVE bias In the formula, Ω out The common-mode component is the compensated component, and G is the system scaling factor.

4. A compensation method for a silicon photonic gyroscope with current modulation and intensity noise compensation function, characterized in that, The compensation method employs any one of the silicon photonic gyroscopes described in claims 1-3 for compensation, and the method includes: The application-specific integrated circuit (ASIC) determines whether the counterclockwise resonant signal is within the resonance valley. If the counterclockwise resonant signal is not within the resonance valley, the temperature control signal is adjusted to perform a linear scan of the temperature control segment of the laser until the counterclockwise resonant signal enters the resonance valley. If the counterclockwise resonant signal is within the resonance valley, the clockwise and counterclockwise resonant signals are demodulated simultaneously to obtain the frequency difference between the laser frequency and the clockwise resonant frequency, and the frequency difference between the laser frequency and the counterclockwise resonant frequency. The application-specific integrated circuit (ASIC) acquires the differential-mode component and common-mode component of the frequency difference between the laser frequency and the clockwise resonant frequency, and the frequency difference between the laser frequency and the counterclockwise resonant frequency. The application-specific integrated circuit (ASIC) determines whether the differential-mode component is 0. If the differential-mode component is 0, the common-mode component is used as the final output signal of the gyroscope. If the differential-mode component is greater than 0, the square wave current signal is down-tuned, and the gyroscope output error caused by the intensity change is obtained based on the differential-mode component and the common-mode component. The common-mode component is then compensated based on the gyroscope output error caused by the intensity change, and the compensated common-mode component is used as the final output signal of the gyroscope. If the differential-mode component is less than 0, the square wave current signal is up-tuned, and the gyroscope output error caused by the intensity change is obtained based on the differential-mode component and the common-mode component. The common-mode component is then compensated based on the gyroscope output error caused by the intensity change, and the compensated common-mode component is used as the final output signal of the gyroscope.

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