Demodulation phase correction method of MEMS gyroscope

Abstract

The invention provides a demodulation phase correction method of an MEMS gyroscope. The demodulation phase correction method comprises the following steps: carrying out effective signal demodulation on an amplified induction mixed signal based on a current demodulation phase to obtain an angular velocity induction signal; performing error signal demodulation on the amplified induction mixed signal based on the current demodulation phase to obtain a detection error mixed signal; obtaining the amplitude of a current detection feedback signal based on the detection error mixed signal; comparing the amplitude value of the current detection feedback signal with a pre-stored reference amplitude value of the detection feedback signal, and if the amplitude value of the current detection feedback signal is not equal to the pre-stored reference amplitude value of the detection feedback signal, detecting the current detection feedback signal; and if not, correcting the current demodulation phase until the amplitude of the current detection feedback signal is equal to the pre-stored reference amplitude of the detection feedback signal, and updating the corrected demodulation phase to the current demodulation phase. In this way, the current demodulation phase can be dynamically corrected, so that the precision of the demodulated angular velocity sensing signal is improved.

Description

Technical Field

[0001] This invention relates to the field of sensor technology, and more specifically to a demodulation phase correction method for a MEMS gyroscope. Background Technology

[0002] A MEMS gyroscope is a high-precision sensor that measures angular velocity based on the Coriolis effect. Chinese patent applications 202211717826.0 and 202111088562.2 both disclose a MEMS gyroscope. Therefore, the basic principles of MEMS gyroscopes will not be introduced here.

[0003] The MEMS gyroscope has two typical operating modes: a driving mode and a sensing mode. The phase difference between the driving mode and the sensing mode... With the frequency of the driving mode Frequency of the induction mode The quality factor Q of the driving mode d Quality factor of inductive mode These parameters are related.

[0004] Specifically, phase difference for

[0005]

[0006]

[0007] in, To be at the reference temperature Quality factor of the inductive mode measured below The value, This is the current temperature. The phase difference is visible. It will change with temperature.

[0008] Because the angular velocity sensing signal generated by the rotation of the MEMS gyroscope will be mixed with the orthogonal error signal, in order to extract the angular velocity sensing signal from the mixed signal, it is usually necessary to take advantage of the fact that the phase angle difference between the angular velocity sensing signal and the orthogonal error signal is exactly 90 degrees.

[0009]

[0010]

[0011]

[0012] in The mixed signal obtained from the detection electrode of the MEMS gyroscope. is the angular velocity sensing signal, is the amplitude of the angular velocity sensing signal, is the quadrature error signal, is the amplitude of the quadrature error signal, is the frequency of the angular velocity sensing signal.

[0013] The effective angular velocity sensing signal is extracted from the mixed signal, usually by using a mixer, by selecting a suitable demodulation phase to demodulate the angular velocity sensing signal, excluding the quadrature error signal. The principle of mixer demodulation is as follows:

[0014]

[0015] wherein is the demodulated angular velocity sensing signal.

[0016] In an ideal state, , after demodulation by the mixer, we get:

[0017]

[0018] After analog-to-digital conversion (Delta-Sigma analog-to-digital converter), the average value of the angular velocity sensing signal can be obtained, i.e.

[0019]

[0020] The quadrature error signal is extracted from the mixed signal, also by using a mixer, by selecting a suitable demodulation phase to demodulate the quadrature error signal :

[0021]

[0022] In an ideal state, , after demodulation by the mixer, we get:

[0023]

[0024] In actual situations, as the environmental temperature or cavity pressure changes, the quality factor of the MEMS gyroscope will change, causing drift, and the amplitude of the drift varies. If this difference is not corrected, the angular velocity sensing signal is still demodulated by the mixer according to , and the angular velocity sensing signal is:

[0025]

[0026] =

[0027]

[0028] After the delta-sigma analog-digital conversion, the average value of the angular velocity sensing signal is:

[0029] .

[0030] If the temperature or the cavity pressure changes, the angular velocity sensing signal will be deviated. is not equal to . SUMMARY

[0031] One of the purposes of the present application is to provide a demodulation phase correction method for MEMS gyroscopes, which can dynamically correct the demodulation phase, thereby improving the precision of the demodulated angular velocity sensing signal.

[0032] According to one aspect of the present application, the present application provides a demodulation phase correction method for MEMS gyroscopes, which comprises: driving the detection mass of the MEMS gyroscope sensing part to perform resonant motion by driving the driving electrode of the MEMS gyroscope sensing part with a driving signal, and applying a detection signal to the detection mass of the MEMS gyroscope sensing part; amplifying the driving feedback signal obtained by the driving feedback electrode of the MEMS gyroscope sensing part; obtaining the phase difference between the driving signal and the angular velocity sensing signal based on the amplified driving feedback signal ; amplifying the sensing mixed signal obtained by the sensing electrode of the MEMS gyroscope sensing part, wherein the sensing mixed signal comprises the angular velocity sensing signal, the quadrature error signal and / or the detection feedback signal, and the phase difference between the detection feedback signal and the angular velocity sensing signal is 90 degrees; obtaining the current demodulation phase based on the amplified sensing mixed signal; demodulating the angular velocity sensing signal based on the current demodulation phase ; demodulating the detection error mixed signal based on the amplified sensing mixed signal, wherein the detection error mixed signal comprises the detection feedback signal and / or the quadrature error signal; obtaining the amplitude of the current detection feedback signal based on the detection error mixed signal; comparing the amplitude of the current detection feedback signal with the reference amplitude of the detection feedback signal stored in advance, and if the amplitude of the current detection feedback signal is equal to the reference amplitude of the detection feedback signal stored in advance, considering that the current demodulation phase does not need to be corrected, and if the amplitude of the current detection feedback signal is not equal to the reference amplitude of the detection feedback signal stored in advance, correcting the current demodulation phase until the amplitude of the current detection feedback signal is equal to the reference amplitude of the detection feedback signal, the corrected demodulation phase is updated to the current demodulation phase .

[0033] Compared with the prior art, the application drives the detection mass block by the detection signal with a predetermined amplitude, so as to obtain the detection feedback signal with a fixed amplitude. In the subsequent operation, the amplitude of the current detection feedback signal is compared with the reference amplitude of the detection feedback signal. If the amplitude of the current detection feedback signal is equal to the reference amplitude of the detection feedback signal, it is considered that the current demodulation phase does not need to be corrected. If the amplitude of the current detection feedback signal is not equal to the reference amplitude of the detection feedback signal, the current demodulation phase is corrected until the amplitude of the current detection feedback signal is equal to the reference amplitude of the detection feedback signal, the corrected demodulation phase is updated to the current demodulation phase , so that the current demodulation phase can be dynamically corrected , so as to improve the precision of the demodulated angular velocity sensing signal and effectively reduce the zero drift and sensitivity error. BRIEF DESCRIPTION OF DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the embodiments of the application, the drawings needed to be used in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative labor. Among them:

[0035] Figure 1 is a structural schematic diagram of the sensing part of the MEMS gyroscope in the application;

[0036] Figure 2 is a simplified flowchart of the demodulation phase correction method of the MEMS gyroscope in the application in one embodiment; and

[0037] Figure 3 is a simplified flowchart of the demodulation phase correction method of the MEMS gyroscope in the application in another embodiment. DETAILED DESCRIPTION

[0038] In order to make the above-mentioned objects, features and advantages of the application more obvious and easy to understand, the application will be further described in detail below with reference to the drawings and specific embodiments.

[0039] As used in this description, the terms "one embodiment" or "an embodiment" mean that a particular feature, structure, or characteristic described in connection with the implementation can be included in at least one implementation of the disclosure. The appearances of the phrase "in one embodiment" or "in an embodiment" in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments.

[0040] The demodulation phase correction method of the MEMS gyroscope can dynamically correct the demodulation phase, thereby improving the accuracy of the demodulated angular velocity sensing signal, and effectively reducing the zero drift and sensitivity error.

[0041] Figure 1 The structure diagram of the sensing part of the MEMS gyroscope. Figure 2 The simplified flowchart of the demodulation phase correction method of the MEMS gyroscope in one embodiment. Figure 3 The simplified flowchart of the demodulation phase correction method of the MEMS gyroscope in another embodiment.

[0042] As Figure 1 shown, the sensing part of the MEMS gyroscope includes a detection mass 110, a driving electrode 120, a driving feedback electrode (not shown), and a sensing electrode 150. The detection mass 110 is connected to an anchor point 130 through an elastic beam 140, the driving electrode 120, the driving feedback electrode (not shown), and the sensing electrode 150 are fixedly arranged on a substrate, and the detection mass 110 is suspended above the substrate. The sensing electrode 150 includes a positive sensing electrode 151 and a negative sensing electrode 152.

[0043] A driving signal drives the detection mass 110 of the MEMS gyroscope sensing part to perform resonant motion (or reciprocating motion) in one direction through the driving electrode 120 of the MEMS gyroscope sensing part, and a detection signal is applied to the detection mass 130 of the MEMS gyroscope sensing part in the present disclosure, so that the detection mass performs resonant motion in another direction. As Figure 1 shown, the detection mass 110 driven by the driving signal performs resonant motion along the X-axis, and the detection mass 110 driven by the detection signal performs resonant motion along the Y-axis. When the rotation along the Z-axis is sensed, the detection mass 110 also performs resonant motion along the Y-axis. It should be noted that in this document, the upward and downward directions are not defined as the Y-axis, and the left and right directions are not defined as the X-axis, but the direction of the resonant motion (i.e., the resonant motion) of the detection mass PM in the driving mode is defined as the X-axis, and the direction of the detection vibration of the detection mass PM in the sensing mode is defined as the Y-axis. That is, if the Figure 1When the sensing part of the MEMS gyroscope is laid horizontally, the detection mass block PM will resonate along the vertical direction in the driving mode. At this time, the left and right direction is the Y-axis and the vertical direction is the X-axis.

[0044] In the driving mode, the driving feedback electrode of the MEMS gyroscope sensing part can obtain the driving feedback signal.

[0045] like Figure 2 As shown, the demodulation phase correction method of the MEMS gyroscope includes the following steps.

[0046] Step 210: Amplify the drive feedback signal obtained from the drive feedback electrode of the MEMS gyroscope sensing section. This step can be achieved by using a charge amplifier to amplify the drive feedback signal.

[0047] Step 220: Perform phase locking based on the amplified drive feedback signal to obtain the phase difference between the drive signal and the angular velocity sensing signal. This step can be achieved by using a phase-locked loop (PLL) to phase-lock the amplified drive feedback signal.

[0048] like Figure 1 As shown, the sensing electrode 150 of the MEMS gyroscope sensing section can obtain a mixed sensing signal, which includes an angular velocity sensing signal, an orthogonal error signal, and / or a detection feedback signal. The phase difference between the detection feedback signal and the angular velocity sensing signal is 90 degrees. The detection feedback signal is the signal caused by the resonant motion of the detection mass block resulting from the application of the detection signal to the detection mass block. The detection signal can be controlled to be applied to the detection mass block. The mixed sensing signal includes the detection feedback signal only when the detection signal is applied to the detection mass block. If the detection signal is not applied to the detection mass block, the mixed sensing signal will not include the detection feedback signal.

[0049] Step 230: Amplify the induced mixed signal obtained from the sensing electrode of the MEMS gyroscope sensing part.

[0050] Step 240, based on the current demodulation phase and phase difference The amplified induced mixed signal is effectively demodulated to obtain the angular velocity induced signal. This step can be performed using a first mixer / demodulator, which can also be called an inductive mixer / demodulator.

[0051] Step 250, analog-to-digital conversion is performed on the angular velocity sensing signal to obtain a digitized angular velocity sensing signal. This step can be performed by an analog-to-digital converter. Preferably, the analog-to-digital converter is a Delta-Sigma analog-to-digital converter.

[0052] Step 260, low-pass filtering is performed on the digitized angular velocity sensing signal to obtain a filtered angular velocity sensing signal. This step can be performed by a low-pass filter.

[0053] Step 270, based on the current demodulation phase and the phase difference error signal demodulation is performed on the amplified sensing mixed signal to obtain a detection error mixed signal, wherein the detection error mixed signal comprises the detection feedback signal and / or the quadrature error signal. This step can be performed by a second mixing demodulator, which can also be referred to as a quadrature mixing demodulator. As described above, the detection error mixed signal comprises the detection feedback signal if the detection signal is applied to the detection mass, and the detection error mixed signal does not comprise the detection feedback signal if the detection signal is not applied to the detection mass.

[0054] Step 285, based on the detection error mixed signal, the amplitude of the current detection feedback signal is obtained. Specifically, the step 285 comprises:

[0055] Step 280, analog-to-digital conversion is performed on the detection error mixed signal to obtain a digitized detection error mixed signal. This step can be performed by an analog-to-digital converter. Preferably, the analog-to-digital converter is a Delta-Sigma analog-to-digital converter.

[0056] Step 290, low-pass filtering is performed on the digitized detection error mixed signal to obtain a filtered detection error mixed signal. This step can be performed by a low-pass filter.

[0057] Step 294, based on the filtered detection error mixed signal at the first time and the filtered detection error mixed signal at the second time, the amplitude of the current detection feedback signal is determined, wherein the filtered detection error mixed signal at the first time does not comprise the detection feedback signal because the detection signal is not applied to the detection mass when the filtered detection error mixed signal at the first time is obtained, the filtered detection error mixed signal at the second time comprises the detection feedback signal because the detection signal is applied to the detection mass when the filtered detection error mixed signal at the second time is obtained, and the amplitude of the current detection feedback signal is determined based on the difference between the filtered detection error mixed signal at the second time and the filtered detection error mixed signal at the first time.

[0058] Step 295, compare the amplitude of the current detection feedback signal with the reference amplitude of the detection feedback signal stored in advance, if the amplitude of the current detection feedback signal is equal to the reference amplitude of the detection feedback signal stored in advance, consider that the current demodulation phase No correction is needed, if the amplitude of the current detection feedback signal is not equal to the reference amplitude of the detection feedback signal stored in advance, the current demodulation phase will be corrected in step 240 Until the amplitude of the current detection feedback signal is equal to the reference amplitude of the detection feedback signal stored in advance, the demodulation phase after correction Update to the current demodulation phase In this way, the current demodulation phase can be dynamically corrected So as to improve the accuracy of the demodulated angular velocity sensing signal, effectively reduce the zero drift and sensitivity error, and reduce the adverse effects caused by changes in environmental temperature or cavity pressure.

[0059] In one embodiment, the frequency of the detection feedback signal is consistent with the frequency of the driving signal, the amplitude of the detection signal is a predetermined amplitude, so that the amplitude of the detection feedback signal is also a predetermined value, and the amplitude of the detection feedback signal demodulated under the predetermined condition is taken as the reference amplitude of the detection feedback signal.

[0060] The detection signal can be a square wave, a triangular wave or a sine wave. The detection feedback signal has a 90 degree phase difference with the effective angular velocity sensing signal which needs to be actually measured, so as not to interfere with the effective angular velocity sensing signal.

[0061] In one embodiment, if the difference between the amplitude of the current detection feedback signal and the reference amplitude of the detection feedback signal stored in advance is less than or equal to a preset range, it is considered that the amplitude of the current detection feedback signal is equal to the reference amplitude of the detection feedback signal stored in advance; if the difference between the amplitude of the current detection feedback signal and the reference amplitude of the detection feedback signal stored in advance is greater than the preset range, it is considered that the amplitude of the current detection feedback signal is not equal to the reference amplitude of the detection feedback signal stored in advance.

[0062] In one embodiment, the detection signal can be applied to the detection mass 110 through the detection electrode 160 of the MEMS gyroscope sensing part. Of course, in other embodiments, the detection signal can also be applied to the detection mass 110 through the self-detection electrode of the MEMS gyroscope sensing part. In another embodiment, the detection signal can also be applied through the sensing electrode of the MEMS gyroscope sensing part.

[0063] It can be seen that the detection mass is applied with a detection signal by the electrode pair in the application, and the amplitude of the detection signal is always a predetermined amplitude. The detection signal drives the detection mass to generate a detection feedback signal, and then the amplitude of the detection feedback signal is detected by a mixing demodulator to correct the demodulation phase . Since the amplitude of the detection signal is always a predetermined amplitude, the amplitude of the detection feedback signal should also be a predetermined value and remain unchanged. In order to avoid interfering with the effective angular velocity sensing signal, the phase difference between the phase of the detection feedback signal and the phase of the angular velocity sensing signal should be 90 degrees, and the frequency of the detection signal is consistent with the frequency of the driving signal.

[0064] The mixing demodulator demodulates the detection feedback signal to obtain:

[0065]

[0066] Among them, is the detection feedback signal in the sensing mixed signal, is the demodulated detection feedback signal.

[0067] Ideally, the demodulated detection feedback signal is as follows:

[0068] )

[0069] Then, the demodulated detection feedback signal is subjected to analog-to-digital conversion and low-pass filtering to obtain the amplitude of the demodulated detection feedback signal. Under predetermined conditions, the measured amplitude of the demodulated detection feedback signal is recorded as the reference amplitude of the detection feedback signal. For example, the MEMS gyroscope can be tested to obtain the reference amplitude of the detection feedback signal at the factory under the reference temperature, and the reference amplitude is stored.

[0070] When in an actual environment, the demodulation phase changes due to changes in environmental temperature or changes in cavity air pressure:

[0071]

[0072]

[0073] Among them is the amplitude of the detection feedback signal.

[0074] After Delta-Sigma analog-to-digital conversion, the average value of the detection feedback signal can be obtained:

[0075]

[0076] The average of the detection feedback signal is low-pass filtered to obtain the amplitude of the current detection feedback signal, the amplitude of the current detection feedback signal is compared with a reference amplitude, and the automatic closed-loop adjustment is obtained so that the amplitude of the current detection feedback signal is equal to the reference amplitude. The corrected can be used to mix and demodulate the angular velocity signal, which can effectively reduce the zero drift and sensitivity error.

[0077] It should be noted that the quadrature error signal itself changes with temperature, and its amplitude and phase will change. Therefore, the signal read by the quadrature error phase changes with temperature, so it cannot be determined whether it is due to the change of the amplitude itself or the error of the demodulation phase . The detection feedback signal generated by the detection signal is known, and the amplitude of the detection signal and the detection feedback signal does not change with temperature and cavity pressure. Therefore, based on the amplitude of the detection feedback signal, the correct demodulation phase can be determined.

[0078] Figure 3 The demodulation phase correction method of the MEMS gyroscope in Figure 2 is essentially the same as the demodulation phase correction method of the MEMS gyroscope in Figure 2 , such as steps 310, 320, 330, and 395 in Figure 3 , steps 210, 220, 230, and 295 in . The difference is that

[0079] In a period of time, in step 340, the in-phase / quadrature frequency demodulator demodulates the amplified in-phase mixed signal based on the current demodulation phase to obtain an angular velocity in-phase signal; in step 350, the angular velocity in-phase signal is analog-to-digital converted to obtain a digitized angular velocity in-phase signal; and in step 360, the digitized angular velocity in-phase signal is low-pass filtered to obtain a filtered angular velocity in-phase signal.

[0080] In another period of time, in step 340, the in-phase / quadrature frequency demodulator demodulates the amplified in-phase mixed signal based on the current demodulation phase The amplified inductive mixed signal is demodulated to obtain a detection error mixed signal, wherein the detection error mixed signal comprises the detection feedback signal and / or the quadrature error signal; in step 385, an amplitude of the current detection feedback signal is obtained based on the detection error mixed signal, and the specific step 385 comprises: in step 350, the detection error mixed signal is time-division multiplexed and analog-to-digital converted to obtain a digitized detection error mixed signal; in step 360, the digitized detection error mixed signal is time-division multiplexed and low-pass filtered to obtain a filtered detection error mixed signal; and in step 294, the amplitude of the current detection feedback signal is determined based on the filtered detection error mixed signal.

[0081] Specifically, the step 294 comprises: determining the amplitude of the current detection feedback signal based on the filtered detection error mixed signal at a first time and the filtered detection error mixed signal at a second time, wherein the detection feedback signal is not included in the filtered detection error mixed signal at the first time when the detection signal is not applied to the detection mass block, the detection feedback signal is included in the filtered detection error mixed signal at the second time when the detection signal is applied to the detection mass block, and the amplitude of the current detection feedback signal is determined based on a difference between the filtered detection error mixed signal at the second time and the filtered detection error mixed signal at the first time.

[0082] In this way, the frequency mixing demodulator, the analog-to-digital converter and the low-pass filter can be multiplexed.

[0083] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example" or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, the person skilled in the art can combine and combine different embodiments or examples described in the present specification.

[0084] Although the embodiments of the present application have been shown and described above, it should be understood that the above embodiments are exemplary and should not be construed as limiting the present application, and those skilled in the art can make changes, modifications and variations to the above embodiments within the scope of the present application.

Claims

1. A demodulation phase correction method for a MEMS gyroscope, characterized in that, It includes: The driving signal drives the detection mass block of the MEMS gyroscope sensing part to resonate through the driving electrode of the MEMS gyroscope sensing part, and applies the detection signal to the detection mass block of the MEMS gyroscope sensing part. The drive feedback signal obtained from the drive feedback electrode of the MEMS gyroscope sensing part is amplified; The phase difference between the drive signal and the angular velocity sensing signal is obtained by phase locking based on the amplified drive feedback signal. ; The sensing mixed signal obtained from the sensing electrodes of the MEMS gyroscope sensing part is amplified, wherein the sensing mixed signal includes an angular velocity sensing signal, an orthogonal error signal, and / or a detection feedback signal, and the phase difference between the detection feedback signal and the angular velocity sensing signal is 90 degrees. Based on the current demodulation phase The amplified induced mixed signal is effectively demodulated to obtain the angular velocity induced signal; Based on the current demodulation phase The amplified inductive mixed signal is demodulated to obtain a detection error mixed signal, wherein the detection error mixed signal includes the detection feedback signal and / or the quadrature error signal; The amplitude of the current detection feedback signal is obtained based on the mixed signal of the detection error; The amplitude of the current detection feedback signal is compared with the pre-stored reference amplitude of the detection feedback signal. If the amplitude of the current detection feedback signal is equal to the pre-stored reference amplitude, then the current demodulation phase is considered to be... No correction is required. If the amplitude of the current detection feedback signal is not equal to the pre-stored reference amplitude of the detection feedback signal, the current demodulation phase will be corrected. The corrected demodulation phase is maintained until the amplitude of the current detection feedback signal equals the pre-stored reference amplitude of the detection feedback signal. Update to the current demodulation phase .

2. The demodulation phase correction method for a MEMS gyroscope according to claim 1, characterized in that, If the difference between the current detection feedback signal amplitude and the pre-stored reference amplitude of the detection feedback signal is less than or equal to a preset range, then the current detection feedback signal amplitude is considered to be equal to the pre-stored reference amplitude of the detection feedback signal. If the difference between the amplitude of the current detection feedback signal and the pre-stored reference amplitude of the detection feedback signal is greater than a preset range, then the amplitude of the current detection feedback signal is considered to be not equal to the pre-stored reference amplitude of the detection feedback signal.

3. The demodulation phase correction method for a MEMS gyroscope according to claim 1, characterized in that, The frequency of the detection feedback signal is the same as the frequency of the drive signal. The detection feedback signal is the signal caused by the resonant motion of the detection mass block after the detection signal is applied to it, and the amplitude of the detection signal applied to the detection mass block is a predetermined amplitude. The amplitude of the detection feedback signal obtained by demodulation under predetermined conditions is used as the reference amplitude of the detection feedback signal.

4. The demodulation phase correction method for a MEMS gyroscope according to claim 1, characterized in that, The detection signal is applied to the detection mass block through the detection electrode, self-test electrode, or sensing electrode of the MEMS gyroscope sensing part.

5. The demodulation phase correction method for a MEMS gyroscope according to claim 1, characterized in that, The MEMS gyroscope includes an inductive mixer demodulator and an orthogonal mixer demodulator. The inductive mixer demodulator is based on the current demodulation phase. The amplified induced mixed signal is effectively demodulated to obtain the angular velocity induced signal; The quadrature mixer demodulator is based on the current demodulation phase. The amplified inductive mixed signal is demodulated to obtain a mixed signal of the detection feedback signal and the orthogonal error signal.

6. The demodulation phase correction method for a MEMS gyroscope according to claim 5, characterized in that, It also includes: The angular velocity sensing signal is converted from analog to digital to obtain a digitized angular velocity sensing signal; The digitized angular velocity sensing signal is low-pass filtered to obtain the filtered angular velocity sensing signal.

7. The demodulation phase correction method for a MEMS gyroscope according to claim 5, characterized in that, The amplitude of the current detection feedback signal obtained based on the aforementioned detection error mixed signal includes: The mixed detection error signal is subjected to analog-to-digital conversion to obtain a digitized mixed detection error signal; The digitized mixed detection error signal is low-pass filtered to obtain the filtered mixed detection error signal; The amplitude of the current detection feedback signal is determined based on the filtered detection error mixture signal at the first time step and the filtered detection error mixture signal at the second time step. Specifically, when the filtered detection error mixture signal at the first time step is obtained, the detection signal is not applied to the detection quality block, so that the filtered detection error mixture signal at the first time step does not include the detection feedback signal. When the filtered detection error mixture signal at the second time step is obtained, the detection signal is applied to the detection quality block, so that the filtered detection error mixture signal at the second time step includes the detection feedback signal. The amplitude of the current detection feedback signal is determined based on the difference between the filtered detection error mixture signal at the second time step and the filtered detection error mixture signal at the first time step.

8. The demodulation phase correction method for a MEMS gyroscope according to claim 1, characterized in that, The MEMS gyroscope includes an inductive / quadrature mixer demodulator. The inductive / quadrature mixer demodulator time-division multiplexes based on the current demodulation phase The amplified induced mixed signal is effectively demodulated to obtain the angular velocity induced signal; The inductive / quadrature mixer demodulator time-division multiplexes based on the current demodulation phase The amplified inductive mixed signal is demodulated to obtain a mixed signal of the detection feedback signal and the orthogonal error signal.

9. The demodulation phase correction method for a MEMS gyroscope according to claim 8, characterized in that, It also includes: The angular velocity sensing signal is time-division multiplexed to perform analog-to-digital conversion to obtain a digitized angular velocity sensing signal; The time-division multiplexing method performs low-pass filtering on the digitized angular velocity sensing signal to obtain the filtered angular velocity sensing signal.

10. The demodulation phase correction method for a MEMS gyroscope according to claim 9, characterized in that, The amplitude of the current detection feedback signal obtained based on the aforementioned detection error mixed signal includes: The time-division multiplexing method performs analog-to-digital conversion on the mixed detection error signal to obtain a digitized mixed detection error signal; The time-division multiplexed low-pass filter is used to obtain the filtered detection error mixed signal; The amplitude of the current detection feedback signal is determined based on the filtered detection error mixture signal at the first time step and the filtered detection error mixture signal at the second time step. Specifically, when the filtered detection error mixture signal at the first time step is obtained, the detection signal is not applied to the detection quality block, so that the filtered detection error mixture signal at the first time step does not include the detection feedback signal. When the filtered detection error mixture signal at the second time step is obtained, the detection signal is applied to the detection quality block, so that the filtered detection error mixture signal at the second time step includes the detection feedback signal. The amplitude of the current detection feedback signal is determined based on the difference between the filtered detection error mixture signal at the second time step and the filtered detection error mixture signal at the first time step.

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