A control system for a Coriolis resonant gyroscope based on a mixing excitation signal

Abstract

This invention discloses a control system for a Coriolis resonant gyroscope based on a mixed-frequency excitation signal, comprising: a mixed-frequency excitation drive closed-loop circuit and a mixed-frequency excitation detection closed-loop circuit. The mixed-frequency excitation drive closed-loop circuit realizes closed-loop drive of the gyroscope, restoring the drive mode vibration signal without feedthrough interference. The mixed-frequency excitation detection closed-loop circuit realizes force balance detection of the gyroscope, restoring the detection mode vibration signal without feedthrough interference. This invention utilizes the square relationship between the excitation voltage and electrostatic force of the capacitor resonator, employs a mixed-frequency excitation resonant signal to separate the resonant signal from the feedthrough interference signal in the frequency domain, and combines filtering technology to obtain a purer gyroscope readout signal, suppressing feedthrough interference.

Description

Technical Field

[0001] This invention relates to the field of Coriolis resonant gyroscope technology, and more particularly to a control system for a Coriolis resonant gyroscope based on a mixed-frequency excitation signal. Background Technology

[0002] The Coriolis resonator gyroscope, a sensor that utilizes the Coriolis effect to sense input angular velocity, is one of the important applications of MEMS technology in inertial navigation. It boasts advantages such as small size, light weight, low cost, mass production capability, and ease of integration, leading to its widespread use and increasingly demanding performance requirements. However, due to non-ideal factors such as manufacturing processes, material properties, and design layout, parasitic capacitance is inevitably introduced into the electrostatic drive and capacitance detection processes of the Coriolis resonator gyroscope. Specifically, the parasitic capacitance between the excitation electrode and the readout electrode introduces interference signals with the same frequency and phase as the excitation signal into the gyroscope's output signal, i.e., feedthrough interference. Feedthrough interference not only reduces the system's signal-to-noise ratio and affects measurement and control accuracy but may also induce unnecessary high-frequency oscillations, thus significantly negatively impacting overall performance.

[0003] To address feedthrough interference, common methods for suppression include optimizing gyroscope structure, electromechanical amplitude modulation, parametric excitation, peripheral circuit compensation, and digital algorithm compensation. However, gyroscope structure optimization involves complex design processes, lengthy manufacturing procedures, and high costs; electromechanical amplitude modulation requires complex modulation and demodulation circuits, potentially increasing power consumption and high-frequency noise; parametric excitation has limited applicability and its feedthrough interference suppression effect is limited; and feedthrough compensation techniques have poor universality, leading to long system debugging cycles. Summary of the Invention

[0004] Purpose of the invention: This invention provides a control system for a Coriolis resonant gyroscope based on a mixed-frequency excitation signal, which separates the resonant signal from the feedthrough interference signal in the frequency domain, and combines filtering technology to obtain a purer gyroscope readout signal while suppressing feedthrough interference.

[0005] Technical Solution: The present invention discloses a control system for a Coriolis resonant gyroscope based on a mixed-frequency excitation signal, comprising: a mixed-frequency excitation drive closed-loop circuit and a mixed-frequency excitation detection closed-loop circuit; the mixed-frequency excitation drive closed-loop circuit realizes closed-loop drive of the gyroscope, restoring the drive mode vibration signal without feedthrough interference; the mixed-frequency excitation detection closed-loop circuit realizes force balance detection of the gyroscope, restoring the detection mode vibration signal without feedthrough interference. The mixed-frequency excitation drive closed-loop circuit ensures that the gyroscope drive frame maintains simple harmonic motion with constant amplitude and stable frequency in the x-axis direction. Therefore, according to the Coriolis effect, the gyroscope will cause the detection frame to vibrate under the action of an external input angular velocity Ω, generating a detection mode vibration signal; the mixed-frequency excitation detection closed-loop circuit dynamically constrains the detection frame to an equilibrium position, improving system stability while acquiring external input angular velocity information.

[0006] Furthermore, the mixed-mode excitation drive closed-loop circuit includes a drive mode mixer circuit, drive mode excitation electrodes, drive mode readout electrodes, drive mode feedthrough capacitors, drive mode C / V conversion circuits, drive mode filtering circuits, phase demodulation modules, amplitude demodulation modules, phase-locked loops, direct digital frequency synthesizers, automatic gain controllers, drive mode amplifier circuits, drive mode A / D conversion circuits, and drive mode D / A conversion circuits. The drive mode mixer circuit mixes the sinusoidal drive signal, modulating its frequency band to a high frequency. The generated drive mode mixing excitation signal acts on the drive mode excitation electrodes, directly causing the drive mode to move at a frequency of ω. x Simple harmonic motion is performed, causing the driving mode readout electrode to generate a frequency of ω. x The sinusoidal vibration current signal, the readout signal output from the drive mode readout electrode, is processed sequentially by the drive mode C / V conversion circuit, the drive mode filtering circuit, and the drive mode A / D conversion circuit, and then sent to the phase demodulation module and the amplitude demodulation module, respectively. The phase demodulation module and the amplitude demodulation module demodulate the vibration signal after the drive mode is restored, respectively, to obtain the drive mode vibration phase information and amplitude information. The phase-locked loop tracks the drive mode resonant frequency ω of the gyroscope based on the phase information. x and ω x The outputs are respectively fed to a direct digital frequency synthesizer and a mixer excitation detection closed-loop circuit. The automatic gain controller generates the amplitude V of the drive signal based on the amplitude information. ac The direct digital frequency synthesizer outputs a frequency of ω. x sinusoidal signal sinω x t, the amplitude of the driving signal and the sinusoidal signal sinω x The driving signal V is obtained by multiplying t. ac sinω xThe gyroscope is driven in a closed-loop manner. The drive signal is processed sequentially by the drive mode D / A conversion circuit, the drive mode amplification circuit, and the drive mode mixer circuit before being sent to the drive mode excitation electrode. The drive mode feedthrough interference current signal generated by the drive mode mixer excitation signal through the drive mode feedthrough capacitor coupling is also modulated to a high frequency. After passing through the drive mode C / V conversion circuit and the drive mode filter circuit, the drive mode feedthrough interference signal is filtered out, restoring the drive mode vibration signal without feedthrough interference.

[0007] Furthermore, the frequency mixing excitation detection closed-loop circuit includes a detection mode mixing circuit, a detection mode excitation electrode, a detection mode readout electrode, a detection mode feedthrough capacitor, a detection mode C / V conversion circuit, a detection mode filtering circuit, a Coriolis signal demodulation module, a force balance detection controller, a detection mode amplifier circuit, a detection mode A / D conversion circuit, and a detection mode D / A conversion circuit. The detection mode mixing circuit mixes the sinusoidal force balance signal, modulating its signal frequency band to a high frequency. The generated mixed excitation signal acts on the detection mode excitation electrode, causing the detection mode excitation electrode to generate a frequency of ω. x The electrostatic force cancels out the vibration signal generated by the detection mode readout electrode based on the angular velocity Ω of the gyroscope's sensitive axis, keeping the detection mode in equilibrium. The detection mode mixing excitation signal, coupled by the detection mode feedthrough capacitor, generates a detection mode feedthrough interference current signal that is also modulated to a high frequency. The readout signal output by the detection mode readout electrode is processed sequentially by the detection mode C / V conversion circuit, the detection mode filtering circuit, and the detection mode A / D conversion circuit before being sent to the Coriolis signal demodulation module. The Coriolis signal demodulation module demodulates the vibration signal of the detection mode readout electrode to obtain the Coriolis signal. The force balance detection controller generates an angular velocity signal based on the Coriolis signal, which comes from the sinω of the drive closed loop. x The force balance signal is generated by multiplying the angular velocity signal output by the force balance detection controller with the t signal, thereby realizing the force balance detection of the gyroscope. The force balance signal is then processed by the detection mode D / A conversion circuit, the detection mode amplification circuit, and the detection mode mixer circuit before being sent to the detection mode excitation electrode. Therefore, after passing through the detection mode C / V conversion circuit and the detection mode filtering circuit, the detection mode feedthrough interference signal is filtered out, and the detection mode vibration signal without feedthrough interference is restored.

[0008] Furthermore, in the driving mode mixing circuit, to excite the gyroscope to drive the mode harmonic vibration, mixing excitation signals need to be applied to the positive and negative excitation electrodes respectively. The mixing excitation signal corresponding to each electrode needs to be modulated by a switching circuit.

[0009] Furthermore, the generation process of the mixing excitation signal corresponding to the positive electrode is as follows: The sinusoidal signal output by the D / A conversion circuit passes through an RC high-pass filter composed of an isolation capacitor and a pull-up resistor, and is then superimposed with a positive DC voltage V. dc The AC / DC coupled signal V is obtained. ac sinω x t+V dc The sinusoidal signal output from the D / A converter circuit passes through an inverting circuit, then through an RC high-pass filter composed of an isolation capacitor and a pull-down resistor, and is superimposed with a negative DC voltage -V. dc Obtain the AC / DC coupled signal -V ac sinω x tV dc The two AC / DC coupled signals are mixed and modulated by a single-pole double-throw switch circuit to obtain the mixing excitation signal V. R .

[0010] Furthermore, the generation process of the mixing excitation signal corresponding to the negative electrode is as follows: the sinusoidal signal output by the D / A conversion circuit passes through an RC high-pass filter composed of an isolation capacitor and a pull-down resistor, and is then superimposed with a negative DC voltage -V. dc The AC / DC coupled signal V is obtained. ac sinω x tV dc The sinusoidal signal output from the D / A converter circuit passes through an inverting circuit, then through an RC high-pass filter composed of an isolation capacitor and a pull-up resistor, and is superimposed with a positive DC voltage V. dc The AC / DC coupled signal -V is obtained. ac sinω x t+V dc The two AC / DC coupled signals are mixed and modulated by a single-pole double-throw switch circuit to obtain the mixing excitation signal V. L The switching cycle of the switch is T. s The duty cycle is 50%.

[0011] Furthermore, the expression for the mixing excitation signal is:

[0012]

[0013] According to the electrostatic driving principle, the electrostatic driving force generated by the mixing excitation signal is:

[0014]

[0015] Where V R V L K represents the excitation signals applied to the positive and negative electrodes, respectively. oThis represents the voltage-to-electrostatic conversion gain, meaning the mixing excitation signal can excite the gyroscope's driving modal harmonic vibration, and the corresponding feedthrough interference signal is modulated to ω. d ±(2n+1)ω s and nω s In the frequency band, n = 1, 2, 3, ..., ∞, the angular frequency ω of the square wave s =2π / T s The cutoff frequency of the driving mode filter circuit is set to ω. x and ω s In this way, it can accurately filter out feedthrough interference signals and restore the ideal gyroscope readout signal.

[0016] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages: (1) The gyroscope vibration signal and the feedthrough interference signal are separated in the frequency domain by using a mixed excitation signal. After the feedthrough interference signal is filtered out by the filter circuit, an excellent feedthrough interference suppression effect can be achieved; (2) The mixed modulation circuit can be implemented by only a switching circuit. The generated mixed excitation signal can directly excite the gyroscope to perform simple harmonic vibration. No complex demodulation circuit is required. It is simple to implement and the circuit power consumption is low; (3) The scheme has strong universality and is applicable to all resonant gyroscopes with different structures that use electrostatic excitation scheme. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the system structure of the present invention.

[0018] Figure 2 This is a schematic diagram of the drive mode mixer circuit of the present invention.

[0019] Figure 3 This is a schematic diagram of the key signal output for the feedthrough suppression process of the present invention. Detailed Implementation

[0020] like Figure 1 As shown, a control system for a Coriolis resonant gyroscope based on a mixed-frequency excitation signal includes: a mixed-frequency excitation drive closed-loop circuit and a mixed-frequency excitation detection closed-loop circuit; the mixed-frequency excitation drive closed-loop circuit realizes the closed-loop drive of the gyroscope, and the mixed-frequency excitation detection closed-loop circuit realizes the force balance detection of the gyroscope.

[0021] The frequency mixing excitation drive closed-loop circuit includes a drive mode mixer circuit, drive mode excitation electrodes, drive mode readout electrodes, drive mode feedthrough capacitors, drive mode C / V conversion circuits, drive mode filtering circuits, phase demodulation modules, amplitude demodulation modules, phase-locked loops, direct digital frequency synthesizers, automatic gain controllers, drive mode amplifier circuits, drive mode A / D conversion circuits, and drive mode D / A conversion circuits. The drive mode mixer circuit mixes the sinusoidal drive signal, modulating its frequency band to a high frequency. The generated drive mode mixing excitation signal acts on the drive mode excitation electrodes, directly causing the drive mode to move at a frequency of ω. x Simple harmonic motion is performed, causing the driving mode readout electrode to generate a frequency of ω. x The sinusoidal vibration current signal, the readout signal output from the drive mode readout electrode, is processed sequentially by the drive mode C / V conversion circuit, the drive mode filtering circuit, and the drive mode A / D conversion circuit, and then sent to the phase demodulation module and the amplitude demodulation module, respectively. The phase demodulation module and the amplitude demodulation module demodulate the vibration signal after the drive mode is restored, respectively, to obtain the drive mode vibration phase information and amplitude information. The phase-locked loop tracks the drive mode resonant frequency ω of the gyroscope based on the phase information. x and ω x The outputs are respectively fed to a direct digital frequency synthesizer and a mixer excitation detection closed-loop circuit. The automatic gain controller generates the amplitude V of the drive signal based on the amplitude information. ac The direct digital frequency synthesizer outputs a frequency of ω. x sinusoidal signal sinω x t, the amplitude of the driving signal and the sinusoidal signal sinω x The driving signal V is obtained by multiplying t. ac sinω x t, to achieve closed-loop drive of the gyroscope;

[0022] The driving signal is processed sequentially through the driving mode D / A conversion circuit, the driving mode amplification circuit, and the driving mode mixer circuit before being sent to the driving mode excitation electrode. The driving mode feedthrough interference current signal generated by the driving mode mixer excitation signal through the driving mode feedthrough capacitor coupling is also modulated to a high frequency. After passing through the driving mode C / V conversion circuit and the driving mode filter circuit, the driving mode feedthrough interference signal is filtered out, restoring the driving mode vibration signal without feedthrough interference.

[0023] The frequency mixing excitation detection closed-loop circuit includes a detection mode mixing circuit, a detection mode excitation electrode, a detection mode readout electrode, a detection mode feedthrough capacitor, a detection mode C / V conversion circuit, a detection mode filtering circuit, a Coriolis signal demodulation module, a force balance detection controller, a detection mode amplifier circuit, a detection mode A / D conversion circuit, and a detection mode D / A conversion circuit. The detection mode mixing circuit mixes the sinusoidal force balance signal, modulating its frequency band to a high frequency. The generated mixed excitation signal acts on the detection mode excitation electrode, causing the detection mode excitation electrode to generate a frequency of ω. x The electrostatic force cancels out the vibration signal generated by the detection mode readout electrode based on the angular velocity Ω of the gyroscope's sensitive axis, keeping the detection mode in equilibrium. The detection mode mixing excitation signal, coupled by the detection mode feedthrough capacitor, generates a detection mode feedthrough interference current signal that is also modulated to a high frequency. The readout signal output by the detection mode readout electrode is processed sequentially by the detection mode C / V conversion circuit, the detection mode filtering circuit, and the detection mode A / D conversion circuit before being sent to the Coriolis signal demodulation module. The Coriolis signal demodulation module demodulates the vibration signal of the detection mode readout electrode to obtain the Coriolis signal. The force balance detection controller generates an angular velocity signal based on the Coriolis signal, which comes from the sinω of the drive closed loop. x The force balance signal is generated by multiplying t with the angular velocity signal output by the force balance detection controller, thereby realizing the force balance detection of the gyroscope;

[0024] The force balance signal is processed sequentially by the detection mode D / A conversion circuit, the detection mode amplification circuit, and the detection mode mixer circuit before being sent to the detection mode excitation electrode. Therefore, after passing through the detection mode C / V conversion circuit and the detection mode filtering circuit, the detection mode feedthrough interference signal is filtered out, restoring the detection mode vibration signal without feedthrough interference.

[0025] like Figure 2 As shown, the driving mode mixer circuit includes: an inverting circuit, an isolation capacitor, a pull-up resistor, a pull-down resistor, and a switching circuit. To excite the gyroscope to drive the modal harmonic vibration, a mixing excitation signal needs to be applied to the positive and negative excitation electrodes respectively. The mixing excitation signal corresponding to each electrode needs to be modulated by the switching circuit.

[0026] The generation process of the mixing excitation signal corresponding to the positive electrode is as follows: The sinusoidal signal output by the D / A conversion circuit passes through an RC high-pass filter composed of an isolation capacitor and a pull-up resistor, and is then superimposed with a positive DC voltage V. dc The AC / DC coupled signal V is obtained. ac sinω x t+V dcThe sinusoidal signal output from the D / A converter circuit passes through an inverting circuit, then through an RC high-pass filter composed of an isolation capacitor and a pull-down resistor, and is superimposed with a negative DC voltage -V. dc Obtain the AC / DC coupled signal -V ac sinω x tV dc The two AC / DC coupled signals are mixed and modulated by a single-pole double-throw switch circuit to obtain the mixing excitation signal V. R .

[0027] The generation process of the mixing excitation signal corresponding to the negative electrode is as follows: The sinusoidal signal output by the D / A conversion circuit passes through an RC high-pass filter composed of an isolation capacitor and a pull-down resistor, and is then superimposed with a negative DC voltage -V. dc The AC / DC coupled signal V is obtained. ac sinω x tV dc The sinusoidal signal output from the D / A converter circuit passes through an inverting circuit, then through an RC high-pass filter composed of an isolation capacitor and a pull-up resistor, and is superimposed with a positive DC voltage V. dc The AC / DC coupled signal -V is obtained. ac sinω x t+V dc The two AC / DC coupled signals are mixed and modulated by a single-pole double-throw switch circuit to obtain the mixing excitation signal V. L The switching cycle of the switch is T. s The duty cycle is 50%.

[0028] The expression for the mixing excitation signal is:

[0029]

[0030] According to the electrostatic driving principle, the electrostatic driving force generated by the mixing excitation signal is:

[0031]

[0032] Where V R V L K represents the excitation signals applied to the positive and negative electrodes, respectively. o This represents the voltage-to-electrostatic conversion gain, meaning the mixing excitation signal can excite the gyroscope's driving modal harmonic vibration, and the corresponding feedthrough interference signal is modulated to ω. d ±(2n+1)ω s and nω s In the frequency band, n = 1, 2, 3, ..., ∞, the angular frequency ω of the square wave s =2π / T s The cutoff frequency of the driving mode filter circuit is set to ω. x and ωs In this way, it can accurately filter out feedthrough interference signals and restore the ideal gyroscope readout signal, such as Figure 3 As shown.

Claims

1. A control system for a Coriolis resonant gyroscope based on a mixing excitation signal, characterized in that, include: Mixing excitation drive closed-loop circuit and mixing excitation detection closed-loop circuit; A frequency mixing excitation drive closed-loop circuit realizes closed-loop drive of the gyroscope, restoring the drive mode vibration signal without feedthrough interference. The frequency mixing excitation drive closed-loop circuit includes a drive mode mixing circuit. In the drive mode mixing circuit, to excite the gyroscope drive mode simple harmonic vibration, a frequency mixing excitation signal needs to be applied to the positive and negative excitation electrodes respectively. The frequency mixing excitation signal corresponding to each electrode needs to be modulated by a switching circuit. A frequency mixing excitation detection closed-loop circuit realizes the force balance detection of the gyroscope, restoring the detection mode vibration signal without feedthrough interference.

2. The control system for the Coriolis resonant gyroscope based on a mixed-frequency excitation signal as described in claim 1, characterized in that, The frequency mixing excitation drive closed-loop circuit includes a drive mode mixer circuit, drive mode excitation electrodes, drive mode readout electrodes, drive mode feedthrough capacitors, drive mode C / V conversion circuits, drive mode filtering circuits, phase demodulation modules, amplitude demodulation modules, phase-locked loops, direct digital frequency synthesizers, automatic gain controllers, drive mode amplifier circuits, drive mode A / D conversion circuits, and drive mode D / A conversion circuits. The drive mode mixer circuit mixes the sinusoidal drive signal, modulating its frequency band to a high frequency. The generated drive mode mixing excitation signal acts on the drive mode excitation electrodes, directly causing the drive mode to move at a frequency of ω. x Simple harmonic motion is performed, causing the driving mode readout electrode to generate a frequency of ω. x The sinusoidal vibration current signal, the readout signal output from the drive mode readout electrode, is processed sequentially by the drive mode C / V conversion circuit, the drive mode filtering circuit, and the drive mode A / D conversion circuit, and then sent to the phase demodulation module and the amplitude demodulation module, respectively. The phase demodulation module and the amplitude demodulation module demodulate the vibration signal after the drive mode is restored, respectively, to obtain the drive mode vibration phase information and amplitude information. The phase-locked loop tracks the drive mode resonant frequency ω of the gyroscope based on the phase information. x and ω x The outputs are respectively fed to a direct digital frequency synthesizer and a mixer excitation detection closed-loop circuit. The automatic gain controller generates the amplitude V of the drive signal based on the amplitude information. ac The direct digital frequency synthesizer outputs a frequency of ω. x sinusoidal signal sinω x t, the amplitude of the driving signal and the sinusoidal signal sinω x The driving signal V is obtained by multiplying t. ac sinω x t, to achieve closed-loop drive of the gyroscope; The driving signal is processed sequentially through the driving mode D / A conversion circuit, the driving mode amplification circuit, and the driving mode mixer circuit before being sent to the driving mode excitation electrode. The driving mode feedthrough interference current signal generated by the driving mode mixer excitation signal through the driving mode feedthrough capacitor coupling is also modulated to a high frequency. After passing through the driving mode C / V conversion circuit and the driving mode filter circuit, the driving mode feedthrough interference signal is filtered out, restoring the driving mode vibration signal without feedthrough interference.

3. The control system for the Coriolis resonant gyroscope based on a mixing excitation signal as described in claim 1, characterized in that, The frequency mixing excitation detection closed-loop circuit includes a detection mode mixing circuit, a detection mode excitation electrode, a detection mode readout electrode, a detection mode feedthrough capacitor, a detection mode C / V conversion circuit, a detection mode filtering circuit, a Coriolis signal demodulation module, a force balance detection controller, a detection mode amplifier circuit, a detection mode A / D conversion circuit, and a detection mode D / A conversion circuit. The detection mode mixing circuit mixes the sinusoidal force balance signal, modulating its frequency band to a high frequency. The generated mixed excitation signal acts on the detection mode excitation electrode, causing the detection mode excitation electrode to generate a frequency of ω. x The electrostatic force cancels out the vibration signal generated by the detection mode readout electrode based on the angular velocity Ω of the gyroscope's sensitive axis, keeping the detection mode in equilibrium. The detection mode mixing excitation signal, coupled by the detection mode feedthrough capacitor, generates a detection mode feedthrough interference current signal that is also modulated to a high frequency. The readout signal output by the detection mode readout electrode is processed sequentially by the detection mode C / V conversion circuit, the detection mode filtering circuit, and the detection mode A / D conversion circuit before being sent to the Coriolis signal demodulation module. The Coriolis signal demodulation module demodulates the vibration signal of the detection mode readout electrode to obtain the Coriolis signal. The force balance detection controller generates an angular velocity signal based on the Coriolis signal, which comes from the sinω of the drive closed loop. x The force balance signal is generated by multiplying t with the angular velocity signal output by the force balance detection controller, thereby realizing the force balance detection of the gyroscope; The force balance signal is processed sequentially by the detection mode D / A conversion circuit, the detection mode amplification circuit, and the detection mode mixer circuit before being sent to the detection mode excitation electrode. Therefore, after passing through the detection mode C / V conversion circuit and the detection mode filtering circuit, the detection mode feedthrough interference signal is filtered out, restoring the detection mode vibration signal without feedthrough interference.

4. The control system for the Coriolis resonant gyroscope based on a mixing excitation signal as described in claim 1, characterized in that, The generation process of the mixing excitation signal corresponding to the positive electrode is as follows: The sinusoidal signal output by the D / A conversion circuit passes through an RC high-pass filter composed of an isolation capacitor and a pull-up resistor, and is then superimposed with a positive DC voltage V. dc The AC / DC coupled signal V is obtained. ac sinω x t+V dc The sinusoidal signal output from the D / A converter circuit passes through an inverting circuit, then through an RC high-pass filter composed of an isolation capacitor and a pull-down resistor, and is superimposed with a negative DC voltage -V. dc Obtain the AC / DC coupled signal -V ac sinω x tV dc The two AC / DC coupled signals are mixed and modulated by a single-pole double-throw switch circuit to obtain the mixing excitation signal V. R .

5. The control system for the Coriolis resonant gyroscope based on a frequency mixing excitation signal as described in claim 1, characterized in that, The generation process of the mixing excitation signal corresponding to the negative electrode is as follows: The sinusoidal signal output by the D / A conversion circuit passes through an RC high-pass filter composed of an isolation capacitor and a pull-down resistor, and is then superimposed with a negative DC voltage -V. dc The AC / DC coupled signal V is obtained. ac sinω x tV dc The sinusoidal signal output from the D / A converter circuit passes through an inverting circuit, then through an RC high-pass filter composed of an isolation capacitor and a pull-up resistor, and is superimposed with a positive DC voltage V. dc The AC / DC coupled signal -V is obtained. ac sinω x t+V dc The two AC / DC coupled signals are mixed and modulated by a single-pole double-throw switch circuit to obtain the mixing excitation signal V. L The switching cycle of the switch is T. s The duty cycle is 50%.

6. The control system for the Coriolis resonant gyroscope based on a frequency mixing excitation signal as described in claim 1, characterized in that, The expression for the mixing excitation signal is: According to the electrostatic driving principle, the electrostatic driving force generated by the mixing excitation signal is: Where V R V L K represents the excitation signals applied to the positive and negative electrodes, respectively. o This indicates the voltage-to-electrostatic conversion gain, meaning the mixing excitation signal can excite the gyroscope's drive modal harmonic vibration, and the corresponding feedthrough interference signal is modulated to... and nω s In the frequency band, n=1,2,3,…,∞, the angular frequency ω of the square wave s =2π / T s The cutoff frequency of the driving mode filter circuit is set to ω. x and ω s In this way, it can accurately filter out feedthrough interference signals and restore the ideal gyroscope readout signal.

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