CN115183861A

CN115183861A - Dynamic self-noise measurement method and system of MHD micro-angle vibration sensor

Info

Publication number: CN115183861A
Application number: CN202211003536.XA
Authority: CN
Inventors: 李醒飞; 刘帆; 李建翔; 朱占霞
Original assignee: Tianjin University
Current assignee: Tianjin University
Priority date: 2022-08-18
Filing date: 2022-08-18
Publication date: 2022-10-14
Anticipated expiration: 2042-08-18
Also published as: CN115183861B

Abstract

The present disclosure provides a dynamic self-noise measurement method and system for an MHD micro-angular vibration sensor, the method comprising: receiving an excitation analog signal sequence by using a controller, wherein the excitation analog signal is obtained by converting a target mixing excitation signal sequence by using a signal conversion module; responding to the excitation analog signal sequence, the controller controls the angular vibration table to vibrate, so that an environmental vibration sensor fixedly connected with the angular vibration table and an MHD micro angular vibration sensor coaxially and fixedly connected with the angular vibration table synchronously vibrate; in response to vibration, the MHD micro-angular vibration sensor generates a first vibration signal, the angular vibration table generates a second vibration signal, and the environmental vibration sensor generates a third vibration signal; and determining a time domain dynamic self-noise sequence and a frequency domain dynamic self-noise power spectral density of the MHD micro-angular vibration sensor according to the first vibration signal, the second vibration signal and the third vibration signal.

Description

Dynamic self-noise measurement method and system of MHD micro-angle vibration sensor

Technical Field

The present disclosure relates to the field of sensor technologies, and in particular, to a dynamic self-noise measurement method and system for an MHD micro-angular vibration sensor, an electronic device, a computer-readable storage medium, and a computer program product.

Background

With the rapid development of the spacecraft, particularly high-precision spacecraft represented by a high-resolution earth observation remote sensing satellite, a deep space exploration remote sensing spacecraft and a deep space laser communication satellite, the spacecraft is very sensitive to a micro-vibration disturbance effect, and the problem of micro-vibration disturbance of a space structure becomes a main factor for limiting the further improvement of the attitude control precision and stability of the high-precision spacecraft.

The Magnetohydrodynamic (MHD) micro-angular vibration sensor has the characteristics of low noise, wide frequency band, miniaturization, long service life and the like, is insensitive to acceleration shock, can measure broadband micro-angular vibration information from a few hertz to one kilohertz, and becomes the most direct, effective and reliable instrument for measuring spacecraft on orbit and payload micro-angular vibration information.

The output signal of the MHD micro-angle vibration sensor during normal operation can be divided into three parts according to the source: a valid signal associated with the input angular vibration excitation, an ambient interference signal, and a self-noise signal. The angular vibration resolution limit is one of the key indicators for measuring the performance of the sensor, and is determined by factors such as the output self-noise and the scale factor of the sensor under the condition of no external environment interference (such as unknown vibration). Therefore, accurate measurement of the output self-noise is of great significance for performance evaluation of the sensor.

In the course of implementing the disclosed concept, the inventors found that there are at least the following problems in the related art: the accuracy of the dynamic self-noise measurement result of the MHD micro-angular vibration sensor is poor.

Disclosure of Invention

In view of the above, the disclosed embodiments provide a dynamic self-noise measurement method, system, electronic device, computer-readable storage medium, and computer program product for an MHD micro-angular vibration sensor.

One aspect of the embodiments of the present disclosure provides a dynamic self-noise measurement method of an MHD micro-angular vibration sensor, including:

receiving an excitation analog signal sequence by using a controller, wherein the excitation analog signal is obtained by converting a target mixing excitation signal sequence by using a signal conversion module;

responding to the excitation analog signal sequence, the controller controls the angular vibration table to vibrate, so that an environmental vibration sensor fixedly connected with the angular vibration table and the MHD micro angular vibration sensor coaxially fixedly connected with the angular vibration table synchronously vibrate;

in response to the vibration, the MHD micro-angular vibration sensor generates a first vibration signal, the angular vibration table generates a second vibration signal, and the ambient vibration sensor generates a third vibration signal;

and determining a time domain dynamic self-noise sequence and a frequency domain dynamic self-noise power spectral density of the MHD micro-angular vibration sensor according to the first vibration signal, the second vibration signal and the third vibration signal.

According to an embodiment of the present disclosure, the determining a time domain dynamic self-noise sequence and a frequency domain dynamic self-noise power spectral density of the MHD micro angular vibration sensor according to the first vibration signal, the second vibration signal and the third vibration signal includes:

calculating a first magnitude squared coherence function and a second magnitude squared coherence function based on the first vibration signal, the second vibration signal, and the third vibration signal, wherein the first magnitude squared coherence function is determined based on the first vibration signal and the second vibration signal, and the second magnitude squared coherence function is determined based on the first vibration signal and a third vibration signal output by an ambient vibration sensor;

respectively constructing an effective signal and an environmental interference signal according to the effective excitation frequency in the first amplitude square coherent function and the environmental interference frequency in the second amplitude square coherent function;

and determining the time domain dynamic self-noise sequence and the frequency domain dynamic self-noise power spectral density according to the first vibration signal, the effective signal and the environment interference signal.

According to an embodiment of the present disclosure, before calculating the first magnitude squared coherence function and the second magnitude squared coherence function, the method further includes:

and respectively removing direct current offset signals in the first vibration signal, the second vibration signal and the third vibration signal to obtain a preprocessed first vibration signal, a preprocessed second vibration signal and a preprocessed third vibration signal.

According to an embodiment of the present disclosure, the obtaining a first amplitude square coherence function and a second amplitude square coherence function according to the first vibration signal, the second vibration signal, and a third vibration signal output by the environmental vibration sensor includes:

determining a first transition function and a second transition function corresponding to the signal according to the signal, a total signal length and the preprocessed first vibration signal for any one of the second vibration signal and the third vibration signal;

and determining the first amplitude square coherence function or the second amplitude square coherence function corresponding to the signal according to the first transition function, the second transition function and a third transition function corresponding to the preprocessed first vibration signal.

According to an embodiment of the present disclosure, the constructing an effective signal and an environmental interference signal according to the effective excitation frequency in the first magnitude square coherence function and the environmental interference frequency in the second magnitude square coherence function respectively includes:

screening the effective excitation frequency corresponding to the first amplitude square coherence function and the environmental interference frequency corresponding to the second amplitude square coherence function from the first amplitude square coherence function and the second amplitude square coherence function based on a first preset threshold and a second preset threshold respectively;

determining a transition amplitude and a transition phase from said first vibration signal and an intermediate function value for any of said first magnitude squared coherence function and said second magnitude squared coherence function, wherein said intermediate function value is determined from said effective excitation frequency or said ambient interference frequency corresponding to said coherence function;

constructing said effective signal based on said transition amplitude and said transition phase corresponding to said first magnitude squared coherence function;

constructing said ambient interference signal based on said transition amplitude and said transition phase corresponding to said second squared magnitude coherence function.

According to an embodiment of the present disclosure, the determining a time domain dynamic self-noise sequence and a frequency domain dynamic self-noise power spectral density according to the first vibration signal, the effective signal, and the environmental interference signal includes:

removing the effective signal and the environmental interference signal from the first vibration signal to obtain the time domain dynamic self-noise sequence;

and determining the power spectrum density of the frequency domain dynamic self-noise according to the time domain dynamic self-noise sequence and the total length of the signal.

According to an embodiment of the present disclosure, the determining the power spectral density of the frequency domain dynamic self-noise according to the time domain dynamic self-noise sequence and the total signal length includes:

determining a new first amplitude square coherence function and a new second amplitude square coherence function according to the time domain dynamic self-noise sequence, the second vibration signal and a third vibration signal, wherein the new first amplitude square coherence function is determined according to the time domain dynamic self-noise sequence and the second vibration signal, and the new second amplitude square coherence function is determined according to the time domain dynamic self-noise sequence and a third vibration signal output by an environmental vibration sensor;

comparing the new first amplitude squared coherence function with a new second amplitude squared coherence function based on the first preset threshold and the second preset threshold, respectively, to obtain a comparison result, where the comparison result indicates whether a new effective signal exists in the new first amplitude squared coherence function and/or whether a new environmental interference signal exists in the new second amplitude squared coherence function;

determining the frequency domain dynamic self-noise power spectral density according to the time domain dynamic self-noise sequence and the total length of the signals under the condition that the comparison result shows that the new effective signal and the new environmental interference signal do not exist;

in case the comparison result indicates the presence of at least one of the new desired signal and the new ambient interference signal, determining the time domain dynamic self-noise sequence as a new first vibration signal for calculating a new first magnitude squared coherence function and a new second magnitude squared coherence function using the new first vibration signal.

According to the embodiment of the present disclosure, the dynamic self-noise measuring method of the MHD micro angular vibration sensor further includes:

generating cosine signals of a plurality of different signal parameters based on the bandwidth of the MHD micro-angular vibration sensor, wherein the signal parameters comprise at least one of: amplitude, frequency and phase;

generating a plurality of initial mixing excitation signal sequences according to a plurality of cosine signals based on the sampling frequency of the cosine signals;

and determining the target mixed excitation signal sequence from a plurality of initial mixed excitation signal sequences according to a peak factor of each initial mixed excitation signal sequence based on a preset range, wherein the peak factor is determined according to a signal peak value and power of the initial mixed excitation signal sequence.

Another aspect of the disclosed embodiments provides a dynamic self-noise measurement system of an MHD micro-angular vibration sensor, including:

the signal conversion module is used for converting the received target frequency mixing excitation signal sequence into an excitation analog signal;

a controller for receiving the excitation analog signal sequence and controlling the angular vibration table to vibrate in response to the excitation analog signal sequence

The angular vibration table is used for generating vibration under the control of the controller and responding to the vibration to output a second vibration signal;

the MHD micro-angular vibration sensor is coaxially and fixedly connected with the table top of the angular vibration table, is used for synchronously vibrating when the angular vibration table vibrates, and responds to the vibration to output a first vibration signal;

an environmental vibration sensor fixedly connected with the base of the angular vibration table, used for synchronously generating vibration under the condition that the angular vibration table generates vibration, responding to the vibration and outputting a third vibration signal;

and the calculation module is used for determining a time domain dynamic self-noise sequence and a frequency domain dynamic self-noise power spectrum density of the MHD micro angular vibration sensor according to the first vibration signal, the second vibration signal and the third vibration signal.

According to an embodiment of the present disclosure, the dynamic self-noise measurement system of the MHD micro angular vibration sensor further includes:

the industrial personal computer is used for executing the following operations:

and determining the target mixed excitation signal sequence from a plurality of initial mixed excitation signal sequences according to a peak factor of each initial mixed excitation signal sequence based on a preset range, wherein the peak factor is determined according to the signal peak value and the power of the initial mixed excitation signal sequence.

Another aspect of an embodiment of the present disclosure provides an electronic device including: one or more processors; memory for storing one or more programs, wherein the one or more programs, when executed by the one or more processors, cause the one or more processors to implement the method as described above.

Another aspect of embodiments of the present disclosure provides a computer-readable storage medium storing computer-executable instructions for implementing the method as described above when executed.

Another aspect of an embodiment of the present disclosure provides a computer program product comprising computer executable instructions for implementing the method as described above when executed.

According to the embodiment of the disclosure, the time domain dynamic self-noise sequence and the frequency domain dynamic self-noise power spectral density of the MHD micro-angular vibration sensor are calculated by the first vibration signal of the MHD micro-angular vibration sensor and combining the second vibration signal of the angular vibration and the third vibration signal of the environmental vibration sensor, so that the problem of large error of a test result caused by introducing other auxiliary MHD micro-angular vibration sensors and adopting priori knowledge is avoided, and the measurement accuracy of the dynamic self-noise of the MHD micro-angular vibration sensor is improved.

Drawings

The above and other objects, features and advantages of the present disclosure will become more apparent from the following description of embodiments of the present disclosure with reference to the accompanying drawings, in which:

fig. 1 schematically shows a flow chart of a dynamic self-noise measurement method of an MHD micro-angular vibration sensor according to an embodiment of the present disclosure;

fig. 2 schematically shows a flow chart of a time domain dynamic self-noise sequence and a frequency domain dynamic self-noise power spectral density determination method according to an embodiment of the present disclosure;

FIG. 3 schematically shows a resulting graph A of coherence coefficients according to an embodiment of the disclosure;

FIG. 4 schematically shows a resulting graph B of coherence coefficients according to an embodiment of the disclosure;

FIG. 5 schematically illustrates a resulting graph of time domain dynamic self-noise sequence and frequency domain dynamic self-noise power spectral density according to an embodiment of the disclosure;

FIG. 6 schematically illustrates a block diagram of a dynamic self-noise measurement system of an MHD micro-angular vibration sensor according to an embodiment of the present disclosure; and

fig. 7 schematically shows a block diagram of an electronic device adapted to implement the above described method according to an embodiment of the present disclosure.

Detailed Description

Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. It should be understood that these descriptions are illustrative only and are not intended to limit the scope of the present disclosure. In the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the embodiments of the disclosure. It may be evident, however, that one or more embodiments may be practiced without these specific details. Moreover, in the following description, descriptions of well-known structures and techniques are omitted so as to not unnecessarily obscure the concepts of the present disclosure.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. The terms "comprises," "comprising," and the like, as used herein, specify the presence of stated features, steps, operations, and/or components, but do not preclude the presence or addition of one or more other features, steps, operations, or components.

All terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art unless otherwise defined. It is noted that the terms used herein should be interpreted as having a meaning that is consistent with the context of this specification and should not be interpreted in an idealized or overly formal sense.

In those instances where a convention analogous to "at least one of A, B, and C, etc." is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., "a system having at least one of A, B, and C" would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.).

Fig. 1 schematically shows a flow chart of a dynamic self-noise measurement method of an MHD micro-angular vibration sensor according to an embodiment of the present disclosure.

As shown in fig. 1, the dynamic self-noise measuring method of the MHD micro angular vibration sensor may include operations S101 to S104.

In operation S101, an excitation analog signal sequence is received by a controller, wherein the excitation analog signal is converted from a target mixed excitation signal sequence by a signal conversion module.

In operation S102, in response to the excitation analog signal sequence, the controller controls the angular vibration table to vibrate such that the ambient vibration sensor fixed to the angular vibration table and the MHD micro angular vibration sensor coaxially fixed to the angular vibration table vibrate in synchronization.

In operation S103, in response to the vibration, the MHD micro-angular vibration sensor generates a first vibration signal, the angular vibration table generates a second vibration signal, and the environmental vibration sensor generates a third vibration signal.

In operation S104, a time domain dynamic self-noise sequence and a frequency domain dynamic self-noise power spectral density of the MHD micro angular vibration sensor are determined according to the first vibration signal, the second vibration signal and the third vibration signal.

According to the embodiment of the disclosure, the target mixed excitation signal sequence may include cosine signals with different performance parameters of K, and the target mixed excitation signal sequence Ω (n) is generated through accumulation. In an exemplary embodiment, the performance parameter may be a frequency, and the frequencies of the K cosine signals cover a bandwidth of the MHD micro angular vibration sensor.

According to the embodiment of the disclosure, the signal conversion module may be a conversion module with a digital-to-analog converter (DAC) and a Low Pass Filter (LPF), which can convert a target mixed excitation signal sequence Ω (N) of an electrical signal type transmitted from a USB bus into an excitation analog signal sequence Ω (t) of a digital type, where N =1 \ 8230n, N is the total number of sampling points, N represents the number of sampling points, and the sampling frequency F is _s Selecting preset multiple of working bandwidth of MHD micro-angle vibration sensor to be tested, such as working bandwidth of MHD micro-angle vibration sensor of 1 Hz-1 kHz, and sampling frequency F _s May be 10 times the operating frequency.

According to the embodiment of the disclosure, the angular vibration table receives the excitation analog signal sequence omega (t) and drives the angular vibration table to output angular vibration so as to generate a second vibration signal u _T (n), the angular vibration table drives the tested MHD micro-angular vibration sensor which is coaxially and rigidly connected, and the mixing angular vibration excitation is input into the MHD micro-angular vibration sensor, so that a first vibration signal u is generated _MHD (n); environment vibration sensor rigidly and fixedly connected on base of angular vibration table can detect environmentThereby generating a third vibration signal u _INF (n)。

According to an embodiment of the present disclosure, the acquired first vibration signal u is utilized _MHD (n) second vibration signal u _T (n) and a third vibration signal u _INF (n) determining a time domain dynamic self-noise sequence and a frequency domain dynamic self-noise power spectral density of the MHD micro-angular vibration sensor.

According to the embodiment of the disclosure, the performance of the MHD micro-angular vibration sensor can be evaluated by the obtained time domain dynamic self-noise sequence and the obtained frequency domain dynamic self-noise power spectral density of the MHD micro-angular vibration sensor, and the accurate test of the dynamic self-noise of the MHD micro-angular vibration sensor in a wide-range input range is met.

Fig. 2 schematically shows a flow chart of a time domain dynamic self-noise sequence and a frequency domain dynamic self-noise power spectral density determination method according to an embodiment of the present disclosure.

As shown in fig. 2, determining a time domain dynamic self-noise sequence and a frequency domain dynamic self-noise power spectral density of the MHD micro-angular vibration sensor according to the first vibration signal, the second vibration signal and the third vibration signal may include operations S201 to S204.

In operation S201, a first magnitude squared coherence function and a second magnitude squared coherence function are calculated according to a first vibration signal, a second vibration signal and a third vibration signal, wherein the first magnitude squared coherence function is determined according to the first vibration signal and the second vibration signal, and the second magnitude squared coherence function is determined according to the first vibration signal and the third vibration signal output by the ambient vibration sensor.

In operation S202, a valid signal and an ambient interference signal are respectively constructed according to a valid excitation frequency in the first amplitude squared coherence function and an ambient interference frequency in the second amplitude squared coherence function.

In operation S203, a time domain dynamic self-noise sequence and a frequency domain dynamic self-noise power spectral density are determined according to the first vibration signal, the effective signal and the environmental interference signal.

According to the embodiment of the disclosure, the effective excitation frequency and the environmental interference frequency are obtained by screening the corresponding first amplitude square coherence function or second amplitude square coherence function by setting the filtering threshold.

According to the embodiment of the disclosure, the amplitude and the phase of the cosine signal of the effective excitation frequency and the environmental interference frequency are calculated by using a nonlinear least square method, and the effective signal y is constructed according to the extracted transition amplitude and transition phase _MT (n) and an environmental interference signal y _MI (n) to thereby generate a first vibration signal u _MHD (n), valid signal y _MT (n) and an environmental interference signal y _MI (n), determining a time domain dynamic self-noise sequence and a frequency domain dynamic self-noise power spectral density.

According to an embodiment of the present disclosure, before calculating the first magnitude squared coherence function and the second magnitude squared coherence function, the following operations may be further included:

respectively removing direct current bias signals in the first vibration signal, the second vibration signal and the third vibration signal to obtain a first vibration signal (y) after pretreatment _MHD (n)), the preprocessed second vibration signal (y) _T (n)) and the preprocessed third vibration signal (y) _INF (n))。

According to the embodiment of the disclosure, since the dc offset signal existing in the first vibration signal, the second vibration signal and the third vibration signal may affect the measurement accuracy of the dynamic self-noise, the dc offset signal of the three vibration signals may be removed to further improve the measurement accuracy of the dynamic self-noise.

According to an embodiment of the present disclosure, DC bias removal is utilizedPreprocessed first vibration signal y obtained after signal arrangement _MHD (n) the preprocessed second vibration signal y _T (n) and the preprocessed third vibration signal y _INF (n) calculating a first amplitude squared coherence function and a second amplitude squared coherence function to determine a time domain dynamic self-noise sequence and a frequency domain dynamic self-noise power spectral density.

According to an embodiment of the present disclosure, obtaining the first amplitude square coherence function and the second amplitude square coherence function according to the first vibration signal, the second vibration signal, and a third vibration signal output by the ambient vibration sensor may include the following operations:

for any one of the second and third vibration signals, a first transition function (G) corresponding to the signal is determined from the signal, the total length (N) of the signal and the preprocessed first vibration signal _i (f) And a second transition function (G) _αβ (f))。

Determining a first amplitude squared coherence function corresponding to the signal according to the first transition function, the second transition function and a third transition function corresponding to the preprocessed first vibration signal

Or a second magnitude squared coherence function

In an exemplary embodiment, the 100s sampled signal u is removed according to equation (1) _MHD (n)、u _T (n) and u _INF (n) DC bias signals to obtain y _MHD (n)、y _T (n) and y _INF (n), wherein MHD, T and INF respectively represent an MHD micro-angular vibration sensor, an angular vibration table and an environmental vibration sensor, mean represents a 100s signal mean value, and MHD, T and INF are abbreviated as M, T and I respectively.

y _i ＝u _i -mean(u _i )，i＝MHD，T，INF. (1)

According to an embodiment of the present disclosure, the first transition of each signal is calculated according to equations (2) and (3), respectivelyFunction G _i (f) And a second transition function G _αβ (f)。

Where f represents the frequency of the signal.

According to an embodiment of the present disclosure, the first transition function G is based on each signal _i (f) A second transition function G _αβ (f) And a third transition function G corresponding to the preprocessed first vibration signal _M (f) Determining a first magnitude squared coherence function corresponding to the signal

Or a second magnitude squared coherence function

Wherein the first magnitude squared coherence function

The second magnitude squared coherence function, as shown in equation (4)

As shown in equation (5).

According to an embodiment of the present disclosure, constructing the effective signal and the environmental interference signal according to the effective excitation frequency in the first amplitude square coherence function and the environmental interference frequency in the second amplitude square coherence function respectively may include the following operations:

and screening the effective excitation frequency corresponding to the first amplitude square coherent function and the environmental interference frequency corresponding to the second amplitude square coherent function from the first amplitude square coherent function and the second amplitude square coherent function respectively based on a first preset threshold and a second preset threshold.

For any one of the first amplitude squared coherence function and the second amplitude squared coherence function, a transition amplitude and a transition phase are determined from the first vibration signal and an intermediate function value, wherein the intermediate function value is determined from an effective excitation frequency or an ambient interference frequency corresponding to the coherence function.

And constructing the effective signal according to the transition amplitude and the transition phase corresponding to the first amplitude squared coherent function. And constructing the environmental interference signal according to the transition amplitude and the transition phase corresponding to the second amplitude square coherent function.

According to an embodiment of the present disclosure, the first preset threshold value

And a second preset threshold

Is artificially determined according to a specific tested MHD micro-angular vibration sensor.

According to the embodiment of the disclosure, the first preset threshold value is set

And a second preset threshold

Respectively screening out effective excitation frequencies f _Tk And the ambient interference frequency f _Ik Expressed as formulas (6) and (7), respectively, wherein f _Tk Denotes the kth effective excitation frequency, having a total of K _T F is _Ik Denotes the kth environmental interference frequency, and has a total of K _I And (4) respectively.

According to an embodiment of the present disclosure, the effective excitation frequency f _Tk And the ambient interference frequency f _Ik One matrix may be constructed separately.

According to the embodiment of the present disclosure, the effective excitation frequency f is calculated according to the nonlinear least square method shown in equations (8) and (9) _Tk And the ambient interference frequency f _Ik Of the cosine signal of (a) (f) _*k ) And a transition phase θ (f) _*k ) And based on the extracted transition amplitude A (f) _*k ) And a transition phase θ (f) _*k ) Constructing the effective signal y shown in the formula (10) _MT (n) and an ambient interference signal y _MI (n)，

Wherein, W _*k Is based on the effective excitation frequency f _Tk Or the ambient interference frequency f _Ik While the preprocessed first vibration signal y can be determined _MHD (n) is written as a column vector.

According to an embodiment of the present disclosure, determining a time domain dynamic self-noise sequence and a frequency domain dynamic self-noise power spectral density according to the first vibration signal, the effective signal and the environmental interference signal may include the following operations:

and removing effective signals and environment interference signals from the first vibration signals to obtain a time domain dynamic self-noise sequence. And determining the power spectrum density of the dynamic self-noise of the frequency domain according to the time domain dynamic self-noise sequence and the total length of the signal.

In an exemplary embodiment, the preprocessed first vibration signal y is preferably used _MHD (n) may be derived from the preprocessed first vibration signal y with reference to equation (11) _MHD (n) eliminating the valid signal y _MT (n) and an environmental interference signal y _MI (n) obtaining a reconstructed time domain dynamic self-noise sequence p _MHD (n) so as to dynamically self-noise sequence p according to the time domain _MHD (N) and the total signal length N, determining the dynamic self-noise power spectral density P of the frequency domain _MHD (n)。

p _MHD (n)＝y _MHD (n)-y _MT (n)-y _MI (n) (11)

According to the embodiment of the present disclosure, determining the frequency domain dynamic self-noise power spectral density according to the time domain dynamic self-noise sequence and the total signal length may include the following operations:

determining a new first amplitude square coherent function and a new second amplitude square coherent function according to the time domain dynamic self-noise sequence, the second vibration signal and the third vibration signal, wherein the new first amplitude square coherent function is determined according to the time domain dynamic self-noise sequence and the second vibration signal, and the new second amplitude square coherent function is determined according to the time domain dynamic self-noise sequence and the third vibration signal output by the environment vibration sensor;

respectively comparing the new first amplitude square coherent function with the new second amplitude square coherent function based on a first preset threshold and a second preset threshold to obtain a comparison result, wherein the comparison result represents whether a new effective signal exists in the new first amplitude square coherent function and/or whether a new environmental interference signal exists in the new second amplitude square coherent function;

determining the power spectrum density of the frequency domain dynamic self-noise according to the time domain dynamic self-noise sequence and the total length of the signals under the condition that the comparison result shows that no new effective signal and new environmental interference signal exist;

in case the comparison result indicates the presence of at least one of a new effective signal and a new ambient interference signal, determining the time domain dynamic self-noise sequence as a new first vibration signal for calculating a new first amplitude squared coherence function and a new second amplitude squared coherence function using the new first vibration signal.

In an exemplary embodiment, the preprocessed first vibration signal p is calculated _MHD (n) and the preprocessed second vibration signal y _T New first magnitude squared coherence function between (n)

Preprocessed first vibration signal p _MHD (n) and the preprocessed third vibration signal y _INF (n) a second magnitude squared coherence function

Using a set first predetermined threshold

And a second preset threshold

Comparing to obtain comparison result, and judging p _MHD (n) whether the significant signal component and the environmental interference component are still contained.

According to the embodiment of the disclosure, if the comparison result shows that the effective signal component and the environmental interference component are still contained, the time domain dynamic self-noise sequence p is obtained _MHD (n) determining as a new first vibration signal y _MHD (n) for calculating a new first amplitude squared coherence function and a new second amplitude squared coherence function using the new first vibration signal.

According to the embodiment of the disclosure, if the comparison result shows that the effective signal component is not contained and the environment is dryCalculating the time domain dynamic self-noise sequence p of the tested MHD micro-angular vibration sensor according to the formula (12) _MHD (n) dynamic self-noise power spectral density P in frequency domain _MHD (f) Wherein, the total length of the signal is N.

According to the embodiment of the disclosure, the time domain dynamic self-noise sequence p _MHD (n) sum frequency domain dynamic self-noise power spectral density P _MHD (f) The dynamic self-noise measurement result of the tested MHD micro-angular vibration sensor is obtained.

According to an embodiment of the present disclosure, the dynamic self-noise measurement method of the MHD micro angular vibration sensor may further include the operations of:

generating a cosine signal of a plurality of different signal parameters based on the bandwidth of the MHD micro-angular vibration sensor, wherein the signal parameters may include at least one of: amplitude, frequency and phase;

and determining a target mixed excitation signal sequence from a plurality of initial mixed excitation signal sequences according to the peak factor of each initial mixed excitation signal sequence based on the preset range, wherein the peak factor is determined according to the signal peak value and the power of the initial mixed excitation signal sequence.

According to an embodiment of the present disclosure, the crest factor may determine a ratio of signal peak value and power, and in an embodiment of the present disclosure, an initial mixed excitation signal sequence with a crest factor of not more than 3 is preferably used.

According to an embodiment of the present disclosure, the generation of the target mixed excitation signal sequence Ω (n) refers to equation (13).

Wherein n is the targetThe serial number of the frequency mixing excitation signal sequence, N =1, \ 8230, N, N is the total point number of the target frequency mixing excitation signal sequence; a. The _k 、f _k And theta _k Respectively representing the amplitude, the frequency and the phase of the kth cosine signal, wherein K =1, \ 8230;, K and K are the number of the cosine signals; f _s Is the sampling frequency.

Fig. 3 schematically shows a resulting diagram a of coherence coefficients according to an embodiment of the disclosure. Fig. 4 schematically shows a resulting diagram B of coherence coefficients according to an embodiment of the disclosure. Fig. 5 schematically shows a resulting diagram of a time domain dynamic self-noise sequence and a frequency domain dynamic self-noise power spectral density according to an embodiment of the disclosure.

In an exemplary embodiment, the target mixed excitation signal sequence Ω (n) used results in effective frequencies of 10Hz, 20Hz, 30Hz, 40Hz, 60Hz, 80Hz, 100Hz. According to the preprocessed first vibration signal y _MHD (n) and the preprocessed second vibration signal y _T (n) a determined first magnitude squared coherence function

The result of the calculation is shown in FIG. 3, based on the first predetermined threshold

And screening the excitation frequency to obtain the effective excitation frequency.

The environmental vibration interference frequency in the test can be determined according to the preprocessed first vibration signal y _MHD (n) and the preprocessed third vibration signal y _INF (n) a determined second magnitude squared coherence function

The result of the calculation is shown in FIG. 3, based on a second predetermined threshold

And screening the signals to obtain the environmental interference frequency. By the method disclosed by the invention, the obtained time domain dynamic self-noise sequence p _MHD (n) calculating eachWith the preprocessed second vibration signal y _T (n) the preprocessed third vibration signal y _INF New first magnitude squared coherence function between (n)

And a new second magnitude squared coherence function

The result of the calculation is shown in FIG. 4. As can be seen from FIG. 4, the first preset threshold is used

And a second preset threshold

Judging time domain dynamic self-noise sequence p _MHD (n) already contains no significant signal components and no environmental interference components, in which case the self-noise sequence p can be dynamically generated in accordance with the time domain _MHD (n) determining the frequency domain dynamic self-noise power spectral density P of the measured MHD micro-angular vibration sensor _MHD (n) wherein the time domain dynamic self-noise sequence p _MHD (n) sum frequency domain dynamic self-noise power spectral density P _MHiD (n) is shown in FIG. 5.

Fig. 6 schematically shows a block diagram of a dynamic self-noise measurement system of an MHD micro-angular vibration sensor according to an embodiment of the present disclosure.

As shown in fig. 6, the dynamic self-noise measurement system 600 of the MHD micro angular vibration sensor may include a signal conversion module 601, a controller 602, an angular vibration table 603, an MHD micro angular vibration sensor 604, an ambient vibration sensor 605, and a calculation module 606.

The signal conversion module 601 is configured to convert the received target mixed excitation signal sequence into an excitation analog signal.

A controller 602, for receiving the excitation analog signal sequence and controlling the angular vibration table 603 to vibrate in response to the excitation analog signal sequence.

An angular vibration stage 603 for generating vibration under the control of the controller 602 and outputting a second vibration signal in response to the vibration.

The MHD micro-angular vibration sensor 604 is coaxially and fixedly connected with the table top of the angular vibration table 603, is used for synchronously vibrating when the angular vibration table 603 vibrates, responds to the vibration and outputs a first vibration signal.

And an environmental vibration sensor 605 fixedly connected to the base of the angular vibration table 603, for synchronously generating vibration when the angular vibration table 603 vibrates, and outputting a third vibration signal in response to the vibration.

And a calculating module 606, configured to determine a time domain dynamic self-noise sequence and a frequency domain dynamic self-noise power spectral density of the MHD micro-angular vibration sensor 604 according to the first vibration signal, the second vibration signal, and the third vibration signal.

According to the embodiment of the disclosure, the time domain dynamic self-noise sequence and the frequency domain dynamic self-noise power spectral density of the MHD micro-angular vibration sensor 604 are calculated by the first vibration signal of one MHD micro-angular vibration sensor 604, combining the second vibration signal of the angular vibration and the third vibration signal of the environmental vibration sensor 605, so that the problem of large error of the test result caused by introducing other auxiliary MHD micro-angular vibration sensors 604 and adopting a priori knowledge is avoided, and the measurement accuracy of the dynamic self-noise of the MHD micro-angular vibration sensor 604 is improved. Meanwhile, the measuring system disclosed by the invention is simple in structure and not easy to generate structural resonance, so that the measuring error is small and the measuring precision is high; the effect of suppressing unknown vibration in the external environment is good; the frequency range of the measurement is large, and the working bandwidth of the MHD micro-angular vibration sensor 604 can be covered.

According to an embodiment of the present disclosure, the calculation module 606 may include a calculation sub-module, a construction sub-module, and a determination sub-module.

A calculation submodule for calculating a first amplitude squared coherence function and a second amplitude squared coherence function based on the first vibration signal, the second vibration signal and the third vibration signal, wherein the first amplitude squared coherence function is determined based on the first vibration signal and the second vibration signal, and the second amplitude squared coherence function is determined based on the first vibration signal and the third vibration signal output by the ambient vibration sensor 605.

And the construction submodule is used for respectively constructing an effective signal and an environmental interference signal according to the effective excitation frequency in the first amplitude square coherent function and the environmental interference frequency in the second amplitude square coherent function.

And the determining submodule is used for determining a time domain dynamic self-noise sequence and a frequency domain dynamic self-noise power spectrum density according to the first vibration signal, the effective signal and the environment interference signal.

According to an embodiment of the present disclosure, the calculation module 606 may further include a pre-processing sub-module.

And the preprocessing submodule is used for respectively removing the direct current offset signals in the first vibration signal, the second vibration signal and the third vibration signal to obtain a preprocessed first vibration signal, a preprocessed second vibration signal and a preprocessed third vibration signal.

According to an embodiment of the present disclosure, the calculation submodule may include a first determination unit and a second determination unit.

And the first determining unit is used for determining a first transition function and a second transition function corresponding to the signals according to the signals, the total length of the signals and the preprocessed first vibration signals aiming at any one of the second vibration signals and the third vibration signals.

And the second determining unit is used for determining a first amplitude square coherence function or a second amplitude square coherence function corresponding to the signal according to the first transition function, the second transition function and a third transition function corresponding to the preprocessed first vibration signal.

According to an embodiment of the present disclosure, the construction sub-module may include a screening unit, a third determination unit, a first construction unit, and a second construction unit.

And the screening unit is used for screening the effective excitation frequency corresponding to the first amplitude square coherence function and the environmental interference frequency corresponding to the second amplitude square coherence function from the first amplitude square coherence function and the second amplitude square coherence function respectively based on a first preset threshold and a second preset threshold.

A third determining unit for determining a transition amplitude and a transition phase from the first vibration signal and an intermediate function value for any one of the first amplitude squared coherence function and the second amplitude squared coherence function, wherein the intermediate function value is determined from an effective excitation frequency or an ambient interference frequency corresponding to the coherence function.

A first construction unit for constructing the effective signal according to the transition amplitude and the transition phase corresponding to the first amplitude squared coherence function.

And the second construction unit is used for constructing the environmental interference signal according to the transition amplitude and the transition phase corresponding to the second amplitude squared coherence function.

According to an embodiment of the present disclosure, the determination submodule may include a culling unit and a fourth determination unit.

And the eliminating unit is used for eliminating the effective signal and the environmental interference signal from the first vibration signal to obtain a time domain dynamic self-noise sequence.

And the fourth determining unit is used for determining the power spectrum density of the frequency domain dynamic self-noise according to the time domain dynamic self-noise sequence and the total signal length.

According to an embodiment of the present disclosure, the fourth determination unit may include a first determination subunit, a comparison subunit, a second determination subunit, and a third determination subunit.

A first determining subunit, configured to determine a new first amplitude squared coherence function and a new second amplitude squared coherence function according to the time-domain dynamic self-noise sequence, the second vibration signal and the third vibration signal, where the new first amplitude squared coherence function is determined according to the time-domain dynamic self-noise sequence and the second vibration signal, and the new second amplitude squared coherence function is determined according to the time-domain dynamic self-noise sequence and the third vibration signal output by the ambient vibration sensor 605.

And the comparing subunit is configured to compare the new first amplitude squared coherent function with the new second amplitude squared coherent function respectively based on a first preset threshold and a second preset threshold, so as to obtain a comparison result, where the comparison result indicates whether a new effective signal exists in the new first amplitude squared coherent function and/or whether a new environmental interference signal exists in the new second amplitude squared coherent function.

And the second determining subunit is used for determining the frequency domain dynamic self-noise power spectral density according to the time domain dynamic self-noise sequence and the total signal length under the condition that the comparison result shows that no new effective signal and no new environment interference signal exist.

A third determining subunit, configured to determine the time-domain dynamic self-noise sequence as a new first vibration signal if the comparison result indicates that at least one of a new effective signal and a new environmental interference signal exists, so as to calculate a new first amplitude squared coherence function and a new second amplitude squared coherence function using the new first vibration signal.

According to an embodiment of the present disclosure, the dynamic self-noise measurement system of the MHD micro-angular vibration sensor 604 may further include an industrial personal computer 607.

The industrial personal computer 607 is used for executing the following operations:

based on the bandwidth of the MHD micro-angular vibration sensor 604, a cosine signal of a plurality of different signal parameters is generated, wherein the signal parameters may include at least one of: amplitude, frequency and phase;

It should be noted that the method executed by the calculation module 606 may be processed by an industrial personal computer, or the calculation module 606 may be integrated in the industrial personal computer.

Any number of modules, sub-modules, units, sub-units, or at least part of the functionality of any number thereof according to embodiments of the present disclosure may be implemented in one module. Any one or more of the modules, sub-modules, units, and sub-units according to the embodiments of the present disclosure may be implemented by being split into a plurality of modules. Any one or more of the modules, sub-modules, units, and sub-units according to the embodiments of the present disclosure may be implemented at least partially as a hardware Circuit, such as a Field Programmable Gate Array (FPGA), a Programmable Logic Array (PLA), a system on a chip, a system on a substrate, a system on a package, an Application Specific Integrated Circuit (ASIC), or may be implemented by hardware or firmware in any other reasonable manner of integrating or packaging a Circuit, or implemented by any one of three implementations of software, hardware, and firmware, or any suitable combination of any of them. Alternatively, one or more of the modules, sub-modules, units, sub-units according to embodiments of the disclosure may be implemented at least partly as a computer program module, which when executed, may perform a corresponding function.

It should be noted that, in the embodiment of the present disclosure, the dynamic self-noise measurement system portion of the MHD micro-angular vibration sensor corresponds to the dynamic self-noise measurement method portion of the MHD micro-angular vibration sensor in the embodiment of the present disclosure, and the description of the dynamic self-noise measurement system portion of the MHD micro-angular vibration sensor specifically refers to the dynamic self-noise measurement method portion of the MHD micro-angular vibration sensor, which is not described herein again.

Fig. 7 schematically shows a block diagram of an electronic device adapted to implement the above described method according to an embodiment of the present disclosure. The electronic device shown in fig. 7 is only an example, and should not bring any limitation to the functions and the scope of use of the embodiments of the present disclosure.

It should be noted that the electronic device 700 of the present disclosure may be configured to implement the function of the computing module 606, and the electronic device 700 is respectively in communication connection with the angular vibration table, the environmental vibration sensor, and the MHD micro-angular vibration sensor through the signal acquisition module to acquire signals output by the angular vibration table, the environmental vibration sensor, and the MHD micro-angular vibration sensor.

The electronic equipment can also be used for realizing the function of an industrial personal computer, and at the moment, the electronic equipment is also required to be in communication connection with the signal conversion module.

As shown in fig. 7, an electronic device 700 according to an embodiment of the present disclosure includes a processor 701, which can perform various appropriate actions and processes according to a program stored in a Read-Only Memory (ROM) 702 or a program loaded from a storage section 708 into a Random Access Memory (RAM) 703. The processor 701 may include, for example, a general purpose microprocessor (e.g., a CPU), an instruction set processor and/or associated chipset, and/or a special purpose microprocessor (e.g., an Application Specific Integrated Circuit (ASIC)), among others. The processor 701 may also include on-board memory for caching purposes. The processor 701 may comprise a single processing unit or a plurality of processing units for performing the different actions of the method flows according to embodiments of the present disclosure.

In the RAM 703, various programs and data necessary for the operation of the electronic apparatus 700 are stored. The processor 701, the ROM 702, and the RAM 703 are connected to each other by a bus 704. The processor 701 performs various operations of the method flows according to the embodiments of the present disclosure by executing programs in the ROM 702 and/or the RAM 703. Note that the programs may also be stored in one or more memories other than the ROM 702 and the RAM 703. The processor 701 may also perform various operations of method flows according to embodiments of the present disclosure by executing programs stored in the one or more memories.

Electronic device 700 may also include input/output (I/O) interface 705, which input/output (I/O) interface 705 is also connected to bus 704, according to an embodiment of the present disclosure. The system 700 may also include one or more of the following components connected to the I/O interface 705: an input portion 706 including a keyboard, a mouse, and the like; an output section 707 including components such as a Cathode Ray Tube (CRT), a Liquid Crystal Display (LCD), and speakers; a storage section 708 including a hard disk and the like; and a communication section 709 including a network interface card such as a LAN card, a modem, or the like. The communication section 709 performs communication processing via a network such as the internet. A drive 710 is also connected to the I/O interface 705 as needed. A removable medium 711 such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, or the like is mounted on the drive 710 as necessary, so that the computer program read out therefrom is mounted in the storage section 708 as necessary.

According to an embodiment of the present disclosure, the method flows involved by the calculation module according to embodiments of the present disclosure may be implemented as computer software programs. For example, embodiments of the present disclosure include a computer program product comprising a computer program embodied on a computer-readable storage medium, the computer program containing program code for performing the method illustrated by the flow chart. In such an embodiment, the computer program can be downloaded and installed from a network through the communication section 709, and/or installed from the removable medium 711. The computer program, when executed by the processor 701, performs the above-described functions defined in the system of the embodiment of the present disclosure. The systems, devices, systems, modules, units, etc. described above may be implemented by computer program modules according to embodiments of the disclosure.

The present disclosure also provides a computer-readable storage medium, which may be embodied in the device/system described in the above embodiments; or may exist separately and not be incorporated into the device/system. The computer-readable storage medium carries one or more programs which, when executed, implement the method according to an embodiment of the disclosure.

According to an embodiment of the present disclosure, the computer-readable storage medium may be a non-volatile computer-readable storage medium. Examples may include, but are not limited to: a portable Computer diskette, a hard disk, a Random Access Memory (RAM), a Read-Only Memory (ROM), an Erasable Programmable Read-Only Memory (EPROM or flash Memory), a portable compact Disc Read-Only Memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the preceding. In the present disclosure, a computer readable storage medium may be any tangible medium that can contain, or store a program for use by or in connection with an instruction execution system, or device.

For example, according to embodiments of the present disclosure, a computer-readable storage medium may include the ROM 702 and/or the RAM 703 and/or one or more memories other than the ROM 702 and the RAM 703 described above.

Embodiments of the present disclosure also include a computer program product comprising a computer program containing program code for performing the method provided by the embodiments of the present disclosure, which, when the computer program product is run on an electronic device, is configured to cause the electronic device to implement the method for dynamic self-noise measurement of an MHD micro-angular vibration sensor provided by the embodiments of the present disclosure.

The computer program, when executed by the processor 701, performs the above-described functions defined in the system/system of the embodiments of the present disclosure. The systems, modules, units, etc. described above may be implemented by computer program modules according to embodiments of the disclosure.

In one embodiment, the computer program may be hosted on a tangible storage medium such as an optical storage device, a magnetic storage device, or the like. In another embodiment, the computer program may also be transmitted in the form of a signal on a network medium, distributed, downloaded and installed via the communication section 709, and/or installed from the removable medium 711. The computer program containing program code may be transmitted using any suitable network medium, including but not limited to: wireless, wired, etc., or any suitable combination of the foregoing.

In accordance with embodiments of the present disclosure, program code for executing computer programs provided by embodiments of the present disclosure may be written in any combination of one or more programming languages, and in particular, these computer programs may be implemented using high level procedural and/or object oriented programming languages, and/or assembly/machine languages. The programming language includes, but is not limited to, programming languages such as Java, C + +, python, the "C" language, or the like. The program code may execute entirely on the user computing device, partly on the user device, partly on a remote computing device, or entirely on the remote computing device or server. In the case of a remote computing device, the remote computing device may be connected to the user computing device through any kind of network, including a Local Area Network (LAN) or a Wide Area Network (WAN), or may be connected to an external computing device (e.g., through the internet using an internet service provider).

The flowchart and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to various embodiments of the present disclosure. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should also be noted that, in some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams or flowchart illustration, and combinations of blocks in the block diagrams or flowchart illustration, can be implemented by special purpose hardware-based systems which perform the specified functions or acts, or combinations of special purpose hardware and computer instructions. Those skilled in the art will appreciate that various combinations and/or combinations of features recited in the various embodiments and/or claims of the present disclosure can be made, even if such combinations or combinations are not expressly recited in the present disclosure. In particular, various combinations and/or combinations of the features recited in the various embodiments and/or claims of the present disclosure may be made without departing from the spirit or teaching of the present disclosure. All such combinations and/or associations are within the scope of the present disclosure.

The embodiments of the present disclosure have been described above. However, these examples are for illustrative purposes only and are not intended to limit the scope of the present disclosure. Although the embodiments are described separately above, this does not mean that the measures in the embodiments cannot be used in advantageous combination. The scope of the disclosure is defined by the appended claims and equivalents thereof. Various alternatives and modifications can be devised by those skilled in the art without departing from the scope of the present disclosure, and such alternatives and modifications are intended to be within the scope of the present disclosure.

Claims

1. A dynamic self-noise measurement method of an MHD micro-angular vibration sensor comprises the following steps:

responding to the excitation analog signal sequence, the controller controls the angular vibration table to vibrate, so that the environmental vibration sensor fixedly connected with the angular vibration table and the MHD micro-angular vibration sensor fixedly connected with the angular vibration table coaxially vibrate synchronously;

2. The method of claim 1, wherein the determining a time domain dynamic self-noise sequence and a frequency domain dynamic self-noise power spectral density of the MHD micro-angular vibration sensor from the first vibration signal, the second vibration signal, and the third vibration signal comprises:

calculating a first amplitude squared coherence function and a second amplitude squared coherence function from the first vibration signal, the second vibration signal, and the third vibration signal, wherein the first amplitude squared coherence function is determined from the first vibration signal and the second vibration signal, and the second amplitude squared coherence function is determined from the first vibration signal and a third vibration signal output by an ambient vibration sensor;

and determining the time domain dynamic self-noise sequence and the frequency domain dynamic self-noise power spectral density according to the first vibration signal, the effective signal and the environmental interference signal.

3. The method of claim 2, wherein prior to calculating the first magnitude squared coherence function and the second magnitude squared coherence function, further comprising:

4. The method of claim 3, wherein said calculating a first magnitude squared coherence function and a second magnitude squared coherence function from the first vibration signal, the second vibration signal, and a third vibration signal output by an ambient vibration sensor comprises:

for any one of the second vibration signal and the third vibration signal, determining a first transition function and a second transition function corresponding to the signal according to the signal, the total signal length and the preprocessed first vibration signal;

5. The method of claim 2, wherein the constructing a desired signal and an ambient interference signal from the desired excitation frequency in the first magnitude squared coherence function and the ambient interference frequency in the second magnitude squared coherence function, respectively, comprises:

screening the effective excitation frequency corresponding to the first amplitude square coherence function and the environmental interference frequency corresponding to the second amplitude square coherence function from the first amplitude square coherence function and the second amplitude square coherence function respectively based on a first preset threshold and a second preset threshold;

determining, for any one of the first magnitude squared coherence function and the second magnitude squared coherence function, a transition amplitude and a transition phase from the first vibration signal and an intermediate function value, wherein the intermediate function value is determined from the effective excitation frequency or the ambient interference frequency corresponding to the coherence function;

constructing the effective signal according to the transition amplitude and the transition phase corresponding to the first amplitude squared coherence function;

and constructing the environmental interference signal according to the transition amplitude and the transition phase corresponding to the second amplitude squared coherence function.

6. The method of claim 5, wherein the determining a time domain dynamic self-noise sequence and a frequency domain dynamic self-noise power spectral density from the first vibration signal, the desired signal, and the environmental interference signal comprises:

7. The method of claim 6, wherein said determining the frequency domain dynamic self-noise power spectral density from the time domain dynamic self-noise sequence and a total signal length comprises:

respectively comparing the new first amplitude squared coherent function with the new second amplitude squared coherent function based on the first preset threshold and the second preset threshold to obtain a comparison result, wherein the comparison result represents whether a new effective signal exists in the new first amplitude squared coherent function and/or whether a new environmental interference signal exists in the new second amplitude squared coherent function;

determining the frequency domain dynamic self-noise power spectral density according to the time domain dynamic self-noise sequence and the total signal length under the condition that the comparison result shows that the new effective signal and the new environmental interference signal do not exist;

determining the time domain dynamic self-noise sequence as a new first vibration signal for calculating a new first amplitude squared coherence function and a new second amplitude squared coherence function using the new first vibration signal, in case the comparison result indicates the presence of at least one of the new effective signal and the new ambient interference signal.

8. The method of claim 1, further comprising:

generating cosine signals of a plurality of different signal parameters based on the bandwidth of the MHD micro-angular vibration sensor, wherein the signal parameters include at least one of: amplitude, frequency and phase;

generating a plurality of initial mixed excitation signal sequences according to a plurality of cosine signals based on the sampling frequency of the cosine signals;

determining the target mixed excitation signal sequence from a plurality of initial mixed excitation signal sequences according to a peak factor of each initial mixed excitation signal sequence based on a preset range, wherein the peak factor is determined according to a signal peak value and power of the initial mixed excitation signal sequence.

9. A dynamic self-noise measurement system of an MHD micro-angular vibration sensor, comprising:

the controller is used for receiving the excitation analog signal sequence and responding to the excitation analog signal sequence to control the angular vibration table to vibrate;

the MHD micro-angular vibration sensor is coaxially and fixedly connected with the table top of the angular vibration table, is used for synchronously vibrating under the condition that the angular vibration table vibrates, responds to the vibration and outputs a first vibration signal;

the environment vibration sensor is fixedly connected with the base of the angular vibration table, is used for synchronously vibrating when the angular vibration table vibrates, responds to the vibration and outputs a third vibration signal;

and the calculation module is used for determining a time domain dynamic self-noise sequence and a frequency domain dynamic self-noise power spectrum density of the MHD micro-angular vibration sensor according to the first vibration signal, the second vibration signal and the third vibration signal.

10. The measurement system of claim 9, further comprising: