Quadrature error suppression system and MEMS gyroscope

文档序号:612696 发布日期:2021-05-07 浏览:16次 中文

阅读说明:本技术 正交误差抑制系统及mems陀螺 (Quadrature error suppression system and MEMS gyroscope ) 是由 王晓 杨拥军 任臣 于 2020-12-30 设计创作,主要内容包括:本发明提供了一种正交误差抑制系统及MEMS陀螺,该系统包括:驱动信号调节模块,其输出端分别连接正交误差信号抑制模块以及MEMS陀螺的解调模块;检测信号调节模块,其输出端连接正交误差信号抑制模块;正交误差信号抑制模块,其输出端连接解调模块;正交误差信号抑制模块,用于将驱动信号调节模块输出的相位调节后的驱动信号和检测信号调节模块输出的滤波处理后的检测信号进行幅度处理,将得到的直流信号与相位调节后的驱动信号进行信号重构,得到正交误差信号,并将检测信号中的正交误差信号进行抑制后得到检测信号中的哥氏力检测信号,从而不需要引入额外的专用结构和电极即可消除正交误差,从而降低工艺难度。(The invention provides a quadrature error suppression system and an MEMS gyroscope, wherein the system comprises: the output end of the driving signal adjusting module is respectively connected with the quadrature error signal suppression module and the demodulation module of the MEMS gyroscope; the output end of the detection signal adjusting module is connected with the quadrature error signal suppression module; the output end of the orthogonal error signal suppression module is connected with the demodulation module; the orthogonal error signal suppression module is used for carrying out amplitude processing on the phase-adjusted driving signal output by the driving signal adjustment module and the filtered detection signal output by the detection signal adjustment module, carrying out signal reconstruction on the obtained direct current signal and the phase-adjusted driving signal to obtain an orthogonal error signal, and suppressing the orthogonal error signal in the detection signal to obtain a Coriolis force detection signal in the detection signal, so that the orthogonal error can be eliminated without introducing an additional special structure and an electrode, and the process difficulty is reduced.)

1. A quadrature error suppression system, comprising: the device comprises a driving signal adjusting module, a detection signal adjusting module and a quadrature error signal suppression module;

the input end of the driving signal adjusting module is used for being connected with the output end of a driving signal ADC of the MEMS gyroscope, and the output end of the driving signal adjusting module is respectively connected with the quadrature error signal suppression module and the demodulation module of the MEMS gyroscope; the driving signal adjusting module is used for adjusting the phase of the received driving digital signal;

the input end of the detection signal adjusting module is used for being connected with the output end of a detection signal ADC of the MEMS gyroscope, and the output end of the detection signal adjusting module is connected with the quadrature error signal suppression module; the detection signal adjusting module is used for filtering the received detection digital signal;

the output end of the quadrature error signal suppression module is connected with the demodulation module; the quadrature error signal suppression module is configured to perform amplitude processing on the phase-adjusted driving signal output by the driving signal adjustment module and the filtered detection signal output by the detection signal adjustment module, perform signal reconstruction on the obtained direct current signal and the phase-adjusted driving signal to obtain a quadrature error signal, and suppress the quadrature error signal in the detection signal and output the quadrature error signal to the demodulation module.

2. The quadrature error suppression system of claim 1, wherein said drive signal adjustment module comprises: a first band-pass filtering unit and a phase adjusting unit;

the input end of the first band-pass filtering unit is the input end of the driving signal adjusting module, and the output end of the first band-pass filtering unit is connected with the first input end of the phase adjusting unit; the first band-pass filtering unit is used for filtering interference signals in the received driving digital signals to obtain first driving signals;

the output end of the phase adjusting unit is the output end of the driving signal adjusting module, and the phase adjusting unit is used for adjusting the phase of the first driving signal to obtain a second driving signal.

3. The quadrature error suppression system of claim 2, wherein said drive signal adjustment module further comprises: a phase compensation unit;

the input end of the phase compensation unit is connected with the temperature sensor of the MEMS gyroscope, and the output end of the phase compensation unit is connected with the second input end of the phase adjustment unit; the phase compensation unit is used for obtaining a phase value to be compensated according to phase change of the phase of the first driving signal along with temperature;

and the phase adjusting unit is used for performing phase compensation on the first driving signal according to the phase value to be compensated based on the phase difference between the first driving signal and the detection signal to obtain a second driving signal.

4. The quadrature error suppression system of claim 3,

the first band-pass filtering unit is a band-pass filter, and the coefficient of the band-pass filter is configured through a register;

the phase compensation unit adopts polynomial fitting to form a phase difference and compensates the change of the phase of the first driving signal along with the temperature; and the polynomial fitting coefficient is configured through a register;

the phase offset of the phase adjustment unit is configured by a register.

5. The quadrature error suppression system of claim 3, wherein said quadrature error signal suppression module comprises: an orthogonal error signal amplitude extraction unit, an orthogonal error signal reconstruction unit and an orthogonal error signal compensation unit;

a first input end of the quadrature error signal amplitude extraction unit is connected with an output end of the phase adjustment unit, a second input end of the quadrature error signal amplitude extraction unit is connected with a first output end of the quadrature error signal compensation unit, and a first output end of the quadrature error signal amplitude extraction unit is connected with a first input end of the quadrature error signal reconstruction unit;

the second input end of the orthogonal error signal reconstruction unit is connected with the output end of the phase adjusting unit, and the output end of the orthogonal error signal reconstruction unit is connected with the first input end of the orthogonal error signal compensation unit;

and a second input end of the orthogonal error signal compensation unit is connected with an output end of the detection signal adjusting module, and a second output end of the orthogonal error signal compensation unit is connected with the demodulation module.

6. The quadrature error suppression system of claim 5, wherein said quadrature error signal magnitude extraction unit comprises: the device comprises a first multiplier subunit, a low-pass filtering subunit and an amplitude adjusting subunit;

a first input end of the first multiplier subunit is a first input end of the quadrature error signal amplitude extraction unit, a second input end of the first multiplier subunit is a first output end of the quadrature error signal compensation unit, and an output end of the first multiplier subunit is connected with an input end of the low-pass filter subunit; the first multiplier unit is used for multiplying the second driving signal by the signal output by the quadrature error signal compensation unit to obtain a signal containing quadrature error amplitude information;

the output end of the low-pass filtering subunit is connected with the input end of the amplitude adjusting subunit; the low-pass filtering subunit is configured to filter the signal including the quadrature error amplitude information to obtain an amplitude of the quadrature error signal;

the output end of the amplitude adjusting subunit is connected with the orthogonal error signal reconstruction unit, and the amplitude adjusting subunit is used for adjusting the amplitude of the orthogonal error signal to obtain a first direct current signal.

7. The quadrature error suppression system of claim 6, wherein said quadrature error signal reconstruction unit comprises: a second multiplier subunit;

a second input end of the second multiplier subunit is connected with an output end of the driving signal adjusting module, and an output end of the second multiplier subunit is connected with a first input end of the quadrature error signal compensating unit; and the second multiplier unit is used for multiplying the first direct current signal and the second driving signal to obtain a quadrature error signal.

8. The quadrature error suppression system of claim 7, wherein said quadrature error signal compensation unit comprises: a subtraction subunit;

the second input end of the subtraction subunit is connected with the output end of the detection signal adjusting module, and the second output end of the subtraction subunit is connected with the demodulation module; and the subtraction subunit is configured to subtract the filtered detection signal output by the detection signal adjustment module from the orthogonal error signal to obtain a signal generated by the coriolis force in the detection signal.

9. The quadrature error suppression system of any of claims 1-8, wherein said detection signal conditioning module comprises: a second band-pass filtering unit;

the input end of the second band-pass filtering unit is used for being connected with the output end of a detection signal ADC of the MEMS gyroscope, and the output end of the detection signal adjusting module is connected with the quadrature error signal suppression module.

10. A MEMS gyroscope, comprising: the quadrature error suppression system of any of claims 1-9 above.

Technical Field

The invention belongs to the technical field of measurement of micro electro Mechanical Systems and micro inertial devices, and particularly relates to a quadrature error suppression system and a Micro Electro Mechanical Systems (MEMS) gyroscope.

Background

The MEMS gyroscope has the characteristics of small volume, light weight, low cost, easiness in realizing batch production and the like, so that the MEMS gyroscope is widely applied to the fields of navigation guidance, robots, automobile safety, consumer electronics, industrial control and the like. The MEMS gyroscope microstructure is manufactured by adopting a bulk silicon or surface silicon processing technology, the mass center motion track of the sensitive mass block cannot be completely coincided with the driving/detecting shaft due to the manufacturing error and the residual stress in the processing, so that the driving shaft direction and the detecting shaft direction are not completely vertical, an orthogonal error signal is generated, and the gyroscope still has output when no angular speed is input.

The quadrature error signal is the main error source for MEMS gyroscope signal detection, and its magnitude will directly affect the final performance of the MEMS gyroscope. The existing method for eliminating the quadrature error mainly comprises the steps of designing a decoupled micro-mechanical structure, synchronous demodulation and micro-electromechanical closed loop. However, designing both the decoupled micro-mechanical structure and the micro-electromechanical closed loop requires designing a special structure and electrode to eliminate the quadrature error, which increases the process difficulty and makes the effect difficult to verify.

Disclosure of Invention

In view of this, embodiments of the present invention provide an orthogonal error suppression system and an MEMS gyroscope, which aim to solve the problem in the prior art that an additional dedicated structure and an electrode are required to be added to eliminate an orthogonal error, thereby increasing the process difficulty.

To achieve the above object, a first aspect of an embodiment of the present invention provides a quadrature error suppression system, including: the device comprises a driving signal adjusting module, a detection signal adjusting module and a quadrature error signal suppression module;

the input end of the driving signal adjusting module is used for being connected with the output end of a driving signal ADC of the MEMS gyroscope, and the output end of the driving signal adjusting module is respectively connected with the quadrature error signal suppression module and the demodulation module of the MEMS gyroscope; the driving signal adjusting module is used for adjusting the phase of the received driving digital signal;

the input end of the detection signal adjusting module is used for being connected with the output end of a detection signal ADC of the MEMS gyroscope, and the output end of the detection signal adjusting module is connected with the quadrature error signal suppression module; the detection signal adjusting module is used for filtering the received detection digital signal;

the output end of the quadrature error signal suppression module is connected with the demodulation module; the quadrature error signal suppression module is configured to perform amplitude processing on the phase-adjusted driving signal output by the driving signal adjustment module and the filtered detection signal output by the detection signal adjustment module, perform signal reconstruction on the obtained direct current signal and the phase-adjusted driving signal to obtain a quadrature error signal, and suppress the quadrature error signal in the detection signal and output the quadrature error signal to the demodulation module.

As another embodiment of the present application, the driving signal adjusting module includes: a first band-pass filtering unit and a phase adjusting unit;

the input end of the first band-pass filtering unit is the input end of the driving signal adjusting module, and the output end of the first band-pass filtering unit is connected with the first input end of the phase adjusting unit; the first band-pass filtering unit is used for filtering interference signals in the received driving digital signals to obtain first driving signals;

the output end of the phase adjusting unit is the output end of the driving signal adjusting module, and the phase adjusting unit is used for adjusting the phase of the first driving signal to obtain a second driving signal.

As another embodiment of the present application, the driving signal adjusting module further includes: a phase compensation unit;

the input end of the phase compensation unit is connected with the temperature sensor of the MEMS gyroscope, and the output end of the phase compensation unit is connected with the second input end of the phase adjustment unit; the phase compensation unit is used for obtaining a phase value to be compensated according to phase change of the phase of the first driving signal along with temperature;

and the phase adjusting unit is used for performing phase compensation on the first driving signal according to the phase value to be compensated based on the phase difference between the first driving signal and the detection signal to obtain a second driving signal.

As another embodiment of the present application, the first band-pass filtering unit is a band-pass filter, and a coefficient of the band-pass filter is configured by a register;

the phase compensation unit adopts polynomial fitting to form a phase difference and compensates the change of the phase of the first driving signal along with the temperature; and the polynomial fitting coefficient is configured through a register;

the phase offset of the phase adjustment unit is configured by a register.

As another embodiment of the present application, the quadrature error signal suppression module includes: an orthogonal error signal amplitude extraction unit, an orthogonal error signal reconstruction unit and an orthogonal error signal compensation unit;

a first input end of the quadrature error signal amplitude extraction unit is connected with an output end of the phase adjustment unit, a second input end of the quadrature error signal amplitude extraction unit is connected with a first output end of the quadrature error signal compensation unit, and a first output end of the quadrature error signal amplitude extraction unit is connected with a first input end of the quadrature error signal reconstruction unit;

the second input end of the orthogonal error signal reconstruction unit is connected with the output end of the phase adjusting unit, and the output end of the orthogonal error signal reconstruction unit is connected with the first input end of the orthogonal error signal compensation unit;

and a second input end of the orthogonal error signal compensation unit is connected with an output end of the detection signal adjusting module, and a second output end of the orthogonal error signal compensation unit is connected with the demodulation module.

As another embodiment of the present application, the quadrature error signal amplitude extracting unit includes: the device comprises a first multiplier subunit, a low-pass filtering subunit and an amplitude adjusting subunit;

a first input end of the first multiplier subunit is a first input end of the quadrature error signal amplitude extraction unit, a second input end of the first multiplier subunit is a first output end of the quadrature error signal compensation unit, and an output end of the first multiplier subunit is connected with an input end of the low-pass filter subunit; the first multiplier unit is used for multiplying the second driving signal by the signal output by the quadrature error signal compensation unit to obtain a signal containing quadrature error amplitude information;

the output end of the low-pass filtering subunit is connected with the input end of the amplitude adjusting subunit; the low-pass filtering subunit is configured to filter the signal including the quadrature error amplitude information to obtain an amplitude of the quadrature error signal;

the output end of the amplitude adjusting subunit is connected with the orthogonal error signal reconstruction unit, and the amplitude adjusting subunit is used for adjusting the amplitude of the orthogonal error signal to obtain a first direct current signal.

As another embodiment of the present application, the orthogonal error signal reconstructing unit includes: a second multiplier subunit;

a second input end of the second multiplier subunit is connected with an output end of the driving signal adjusting module, and an output end of the second multiplier subunit is connected with a first input end of the quadrature error signal compensating unit; and the second multiplier unit is used for multiplying the first direct current signal and the second driving signal to obtain a quadrature error signal.

As another embodiment of the present application, the quadrature error signal compensation unit includes: a subtraction subunit;

the second input end of the subtraction subunit is connected with the output end of the detection signal adjusting module, and the second output end of the subtraction subunit is connected with the demodulation module; and the subtraction subunit is configured to subtract the filtered detection signal output by the detection signal adjustment module from the orthogonal error signal to obtain a signal generated by the coriolis force in the detection signal.

As another embodiment of the present application, the detection signal adjusting module includes: a second band-pass filtering unit;

the input end of the second band-pass filtering unit is used for being connected with the output end of a detection signal ADC of the MEMS gyroscope, and the output end of the detection signal adjusting module is connected with the quadrature error signal suppression module.

A second aspect of an embodiment of the present invention provides a MEMS gyroscope, including: the quadrature error suppression system of any of the above embodiments.

Compared with the prior art, the embodiment of the invention has the following beneficial effects: compared with the prior art, the quadrature error signal suppression module performs amplitude processing on the phase-adjusted driving signal output by the driving signal adjustment module and the filtered detection signal output by the detection signal adjustment module, performs signal reconstruction on the obtained direct current signal and the phase-adjusted driving signal to obtain a quadrature error signal, suppresses the quadrature error signal in the detection signal, outputs a coriolis force detection signal in the detection signal, and outputs the coriolis force detection signal to the demodulation module, so that the quadrature error can be eliminated without introducing an additional special structure and an electrode, and the process difficulty is reduced.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise.

Fig. 1 is a schematic diagram of a quadrature error suppression system provided by an embodiment of the present invention;

FIG. 2 is a schematic diagram of a driving signal conditioning module provided by an embodiment of the invention;

fig. 3 is a schematic diagram of a quadrature error signal suppression module according to an embodiment of the present invention;

fig. 4 is a schematic diagram of a quadrature error signal amplitude extraction unit according to an embodiment of the present invention.

Detailed Description

In the following description, for purposes of explanation and not limitation, specific details are set forth, such as particular system structures, techniques, etc. in order to provide a thorough understanding of the embodiments of the invention. It will be apparent, however, to one skilled in the art that the present invention may be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present invention with unnecessary detail.

In order to explain the technical means of the present invention, the following description will be given by way of specific examples.

Fig. 1 is a schematic diagram of a quadrature error suppression system according to an embodiment of the present invention, which is described in detail below.

A quadrature error suppression system, may comprise: a driving signal adjusting module 1, a detection signal adjusting module 2 and a quadrature error signal suppressing module 3.

The input end of the driving signal adjusting module 1 is used for being connected with the output end of a driving signal ADC of the MEMS gyroscope, and the output end of the driving signal adjusting module 1 is respectively connected with the quadrature error signal suppression module 3 and a demodulation module of the MEMS gyroscope; the driving signal adjusting module 1 is configured to perform phase adjustment on the received driving digital signal.

As shown in fig. 1, the driving detection structure is used to output the capacitance variation of the MEMS gyroscope driving detection structure under the action of the input signal, and since the capacitance variation cannot be directly measured, it is converted into a voltage signal using a C/V converter. The voltage signal is converted into a Digital signal by an Analog-to-Digital Converter (ADC), and is input to the driving signal adjusting module.

The input end of the detection signal adjusting module 2 is used for being connected with the output end of a detection signal ADC of the MEMS gyroscope, and the output end of the detection signal adjusting module 2 is connected with the quadrature error signal suppression module 3; and the detection signal adjusting module 2 is used for filtering the received detection digital signal.

As shown in fig. 1, the sensing structure is used to output the capacitance variation of the MEMS gyroscope under the action of the input signal, and since the capacitance variation cannot be directly measured, it is converted into a voltage signal by using a C/V converter. The voltage signal is converted into a Digital signal by an Analog-to-Digital Converter (ADC), and is input to the detection signal adjusting module.

The output end of the quadrature error signal suppression module 3 is connected with the demodulation module; the quadrature error signal suppression module 3 is configured to perform amplitude processing on the phase-adjusted driving signal output by the driving signal adjustment module 1 and the filtered detection signal output by the detection signal adjustment module 2, perform signal reconstruction on the obtained direct current signal and the phase-adjusted driving signal to obtain a quadrature error signal, and suppress the quadrature error signal in the detection signal and output the quadrature error signal to the demodulation module.

According to the orthogonal error suppression system, the orthogonal error signal suppression module is used for carrying out amplitude processing on the phase-adjusted driving signal output by the driving signal adjustment module and the filtered detection signal output by the detection signal adjustment module, carrying out signal reconstruction on the obtained direct current signal and the phase-adjusted driving signal to obtain the orthogonal error signal, and after the orthogonal error signal in the detection signal is suppressed, outputting the Gothich force detection signal in the detection signal and outputting the Gothich force detection signal to the demodulation module, so that the orthogonal error can be eliminated without introducing an additional special structure and electrodes, and the process difficulty is reduced.

Optionally, as shown in fig. 2, the driving signal adjusting module 1 includes: a first band-pass filtering unit 11 and a phase adjusting unit 12;

the input end of the first band-pass filtering unit 11 is the input end of the driving signal adjusting module 1, and the output end of the first band-pass filtering unit 11 is connected to the first input end of the phase adjusting unit 12; the first band-pass filtering unit 11 is configured to filter an interference signal in the received driving digital signal to obtain a first driving signal;

the output end of the phase adjusting unit 12 is the output end of the driving signal adjusting module 1, and the phase adjusting unit 12 is configured to adjust the phase of the first driving signal to obtain a second driving signal.

Optionally, since the phase of the driving signal may change with the change of temperature, so as to affect the performance of the MEMS gyroscope, the driving signal adjusting module 1 may further include: a phase compensation unit 13;

the input end of the phase compensation unit 13 is connected to the temperature sensor of the MEMS gyroscope, and the output end of the phase compensation unit 13 is connected to the second input end of the phase adjustment unit 12; the phase compensation unit 13 is configured to obtain a phase value to be compensated according to a phase change of the phase of the first driving signal along with the temperature;

the phase adjusting unit 12 is configured to perform phase compensation on the first driving signal according to the phase value to be compensated based on the phase difference between the first driving signal and the detection signal, so as to obtain a second driving signal.

The temperature sensor is used for detecting the temperature of the position where the MEMS gyroscope is located.

Optionally, the first bandpass filtering unit 11 may be a bandpass filter, and coefficients thereof may be configured by a register to meet requirements of MEMS gyroscopes with different driving frequencies.

The phase compensation unit 13 may adopt a polynomial to fit a phase difference, and compensate for a change of the phase of the first driving signal with temperature; and the polynomial fitting coefficients may be configured by registers.

The phase offset of the phase adjustment unit 12 may be configured by a register.

Optionally, the detection signal adjusting module 2 includes: a second band-pass filtering unit;

the input end of the second band-pass filtering unit is used for being connected with the output end of a detection signal ADC of the MEMS gyroscope, and the output end of the detection signal adjusting module is connected with the quadrature error signal suppression module. The second band-pass filtering unit can be a band-pass filter and is used for filtering interference signals in the detection signals, and the coefficients of the band-pass filter can be configured through a register so as to meet the requirements of MEMS gyroscopes with different detection frequencies.

Optionally, as shown in fig. 3, the quadrature error signal suppressing module 3 includes: quadrature error signal amplitude extraction section 31, quadrature error signal reconstruction section 32, and quadrature error signal compensation section 33.

A first input end of the quadrature error signal amplitude extraction unit 31 is connected to the output end of the phase adjustment unit 12, a second input end of the quadrature error signal amplitude extraction unit 31 is connected to the first output end of the quadrature error signal compensation unit 33, and a first output end of the quadrature error signal amplitude extraction unit 31 is connected to the first input end of the quadrature error signal reconstruction unit 32. The quadrature error signal amplitude extraction unit 31 is configured to perform amplitude processing after fusing the second driving signal and the filtered detection signal output by the detection signal adjustment module, so as to obtain a direct current signal.

A second input end of the quadrature error signal reconstructing unit 32 is connected to the output end of the phase adjusting unit 12, and an output end of the quadrature error signal reconstructing unit 32 is connected to a first input end of the quadrature error signal compensating unit 33; the orthogonal error signal reconstruction unit 32 is configured to perform signal reconstruction on the obtained direct current signal and the second driving signal to obtain an orthogonal error signal.

A second input end of the quadrature error signal compensation unit 33 is connected to the output end of the detection signal adjusting module 2, and a second output end of the quadrature error signal compensation unit 33 is connected to the demodulation module. The quadrature error signal compensation unit 33 is configured to compensate the quadrature error signal.

Optionally, as shown in fig. 4, the quadrature error signal amplitude extracting unit 31 may include: a first multiplier subunit 311, a low-pass filtering subunit 312, and an amplitude adjustment subunit 313.

A first input terminal of the first multiplier subunit 311 is a first input terminal of the quadrature error signal amplitude extraction unit 31, a second input terminal of the first multiplier subunit 311 is a first output terminal of the quadrature error signal compensation unit 33, and an output terminal of the first multiplier subunit 311 is connected to an input terminal of the low-pass filter subunit 312; the first multiplier unit 311 is configured to multiply the second driving signal with the signal output by the quadrature error signal compensation unit 33 to obtain a signal containing quadrature error amplitude information;

the output end of the low-pass filtering subunit 312 is connected with the input end of the amplitude adjusting subunit 313; the low-pass filtering subunit 312 is configured to filter the signal containing the quadrature error amplitude information, filter a high-frequency interference signal, and obtain an amplitude of the quadrature error signal;

the output end of the amplitude adjusting subunit 313 is connected to the quadrature error signal reconstructing unit 32, and the amplitude adjusting subunit 313 is configured to adjust the amplitude of the quadrature error signal to obtain a first direct current signal.

Optionally, the orthogonal error signal reconstructing unit 32 includes: a second multiplier subunit;

a second input end of the second multiplier subunit is connected to the output end of the driving signal adjusting module 1, and optionally, a second input end of the second multiplier subunit is connected to the output end of the phase adjusting unit 12; the output end of the second multiplier unit is connected with the first input end of the quadrature error signal compensation unit 33; and the second multiplier unit is used for multiplying the second direct current signal by the second driving signal to obtain an orthogonal error signal.

Optionally, the quadrature error signal compensation unit 33 includes: a subtraction subunit;

the second input end of the subtraction subunit is connected with the output end of the detection signal adjusting module 2, and the second output end of the subtraction subunit is connected with the demodulation module; the subtraction subunit is configured to subtract the filtered detection signal output by the detection signal adjustment module 2 from the orthogonal error signal, that is, subtract the orthogonal error signal in the detection signal, to obtain a signal generated by the coriolis force in the detection signal.

Optionally, the following verifies the quadrature error suppression system provided in this embodiment, and it is assumed that the driving signal output by the driving signal adjusting module 1 is xd(t)=A*sin(wdt) i.e. the second drive signal is xd(t)=A*sin(wdt) in which xd(t) represents a drive signal at time t, A represents a drive signalAmplitude, wdRepresenting the resonant frequency of the drive signal. The detection signal output by the detection signal adjusting module 2 is xs(t)=A1*cos(wdt)+A2sin(wdt) in which xs(t) represents the detection signal at time t, a1 represents the amplitude of the detection signal, which contains the input angular velocity and the detection resonance frequency, and a2 represents the amplitude of the quadrature error signal. The detection signal is composed of two parts, the first part is the detection signal generated by the Coriolis force, and the second part is the quadrature error signal.

Initially, there is no input signal at the first input end of the quadrature error signal compensation module 33, so the detection signal output by the detection signal adjusting module 2 is forwarded to the quadrature error signal amplitude extracting module through the quadrature error signal compensation module 33, and the second driving signal output by the driving signal adjusting module 1 is processed by the first multiplier unit 311, that is, the first driving signal and the second driving signal are output by the driving signal adjusting module 1

Wherein x isd(t)*xs(t) the obtained signal containing the quadrature error amplitude information is filtered by the low-pass filtering subunit 312 to obtain a dc signal containing the quadrature error amplitude information; and then the amplitude adjusting subunit 313 obtains a first direct current signal K × a 2.

The first dc signal K x a2 output by the quadrature error signal amplitude extraction unit 31 and the second driving signal output by the driving signal adjustment module 1 are processed by a second multiplier unit, i.e. xe(t)=A*sin(wdt) K A2, wherein xe(t) represents a quadrature error signal.

The quadrature error signal is input to a subtraction subunit which subtracts the quadrature error signal, x, from the detected signalsf(t)=A1*cos(wdt)+A2sin(wdt)-A*sin(wdt) K a 2. When in useIn the process, after the subtraction subunit, only the signal part generated by the coriolis force remains in the detection signal, namely, the influence of the quadrature error signal on the output signal of the MEMS gyroscope is eliminated.

It should be noted that, in practice, due to the precision of the phase adjuster of the phase adjusting unit 12, there will be a phase difference between the driving signal and the detection signal, which is noted asThe second drive signal may be

The second driving signal and the detection signal are obtained after being processed by the first multiplier subunit 311 and the low-pass filter subunit 312 of the quadrature error signal amplitude extraction module 31

The quadrature error signal reconstructed by the quadrature error signal reconstruction unit 32 may be

The detection signal compensated by the quadrature error signal compensation unit 33 may be

It can thus be seen that there is a need for,a signal representing the detection of the coriolis force is indicated,representing quadrature error signals, positiveThe quadrature error signal is subjected to quadrature error suppression from the original A2 signal to becomeThe quadrature error signal is suppressed.

But it can be seen from the above equation that a new error is introduced in the coriolis force detection signal. The error is related to the phase difference between the driving signal and the detection signal and changes along with the change of the temperature of the position where the MEMS gyroscope is located, therefore, a phase compensation unit 13 is introduced into the system, and the change quantity of the phase difference along with the temperature is reduced.

Since the curve of the phase difference varying with the temperature is relatively linear or relatively smooth, the phase compensation unit 13 may perform the phase compensation by using a temperature compensation algorithm of polynomial fitting, so that the second-order polynomial fitting is taken as an example, and the phase difference is fitted asWhereinTo fit the phase difference, T is the temperature, a1、a2、a3Fitting coefficients for the polynomial.

The phase difference is expressed asWhereinIn order to be the phase difference,is the phase difference value of the current temperature point. New errors introduced in the coriolis force detection signal can be eliminated.

According to the orthogonal error suppression system, the amplitude extraction module is used for carrying out amplitude processing on the second driving signal output by the driving signal regulation module and the detection signal output by the detection signal regulation module to obtain a first direct current signal, the orthogonal error signal reconstruction unit is used for multiplying the first direct current signal by the second driving signal to obtain an orthogonal error signal, the orthogonal error signal compensation unit is used for subtracting the orthogonal error signal from the detection signal output by the detection signal regulation module to obtain a signal generated by the Coriolis force in the detection signal, and the orthogonal error signal is suppressed. In addition, the phase compensation unit in the driving signal adjusting module can be used for carrying out temperature compensation on the phase difference, so that the MEMS gyroscope has better performance under the environment with severe temperature change.

It should be understood that, the sequence numbers of the steps in the foregoing embodiments do not imply an execution sequence, and the execution sequence of each process should be determined by its function and inherent logic, and should not constitute any limitation to the implementation process of the embodiments of the present invention.

An embodiment of the present invention further provides an MEMS gyroscope, including: the quadrature error suppression system provided by any of the above embodiments has the beneficial effects brought by the quadrature error suppression system provided by any of the above embodiments.

The above-mentioned embodiments are only used for illustrating the technical solutions of the present invention, and not for limiting the same; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the spirit and scope of the embodiments of the present invention, and are intended to be included within the scope of the present invention.

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