Random polymorphic wave modulation method of interference type integrated optical gyroscope

Abstract

The invention discloses a random polymorphic wave modulation method of an interference type integrated optical gyroscope, which aims at a scene that the integration level of the integrated optical gyroscope is improved by compressing the length of an interference loop, the modulation frequency is obviously increased and crosstalk noise is introduced, and comprises the following steps of: firstly, according to a constraint condition and a preset modulation sequence library; generating a pseudo-random number sequence to construct a multi-state selector, and randomly selecting the sequence output at the current moment; generating another pseudo random number sequence at the same time; and a time-varying composite modulation generation matrix is constructed, and random multi-state wave modulation signals are uniformly represented and output. Then, collecting a digital quantity corresponding to the light intensity signal, and completing the angular velocity calculation of the integrated optical gyroscope through a demodulation sequence; according to the method, modulation voltage randomization is realized through a random polymorphic wave sequence state transition path, so that the crosstalk noise mean value is suppressed to be 0, the crosstalk noise introduced by high modulation frequency in the integrated optical gyroscope is effectively suppressed, and finally the dead zone of the gyroscope is reduced.

Description

Technical Field

[0001] This invention belongs to the field of inertial measurement, specifically a random multi-state wave modulation method for an interferometric integrated optical gyroscope. Background Technology

[0002] In recent years, new concept motion vehicles such as drone swarms and autonomous driving have emerged. The complexity and diversity of their environments require guidance systems with high-precision navigation and positioning capabilities, while also maintaining high stability and anti-interference capabilities in various complex and extreme environments. This has created an urgent need for inertial navigation systems to utilize gyroscope devices that balance high performance with miniaturization, low cost, and lightweight design.

[0003] Integrated optical gyroscopes have become a research hotspot due to their low cost, extremely high transmission speeds for optical and electrical signals, and ability to achieve instantaneous warm-up and startup. The integration level of gyroscopes is improved through methods such as replacing fiber optic loops with waveguide loops and integrating optical components. However, increasing the integration level also brings new challenges to signal detection. The main reason is that when the interference loop of the gyroscope is short, the transit time and intrinsic frequency limit the required modulation frequency for matching. Under high-frequency conditions, crosstalk noise is significant, limiting the performance of the gyroscope. Traditional square wave modulation and random modulation both have limitations; the former cannot suppress crosstalk noise, and the latter has an unstable demodulation period and poor dynamic performance.

[0004] Therefore, how to achieve high dynamic signal detection of integrated optical gyroscopes under short interference length conditions, and effectively suppress crosstalk noise while ensuring the dynamic performance of the gyroscope, remains a difficult problem to be solved. Summary of the Invention

[0005] To address the challenge of effectively suppressing crosstalk noise while maintaining the dynamic performance of an integrated optical gyroscope under short interference length conditions, this invention proposes a random multi-state wave modulation method for interferometric integrated optical gyroscopes, which can significantly suppress crosstalk noise while ensuring closed-loop performance.

[0006] The random multi-state wave modulation method for the interferometric integrated optical gyroscope comprises the following steps:

[0007] Step 1: While integrating optical gyroscopes increases integration density by compressing the interference loop length, it significantly increases the modulation frequency, inevitably introducing crosstalk noise. A random polymorphic wave sequence state transition path is designed. By generating a random polymorphic wave modulation sequence, the modulation voltage is randomized, giving it white noise characteristics. This results in a crosstalk noise mean of 0, effectively reducing crosstalk noise and thus decreasing the dead zone width.

[0008] The state transition path of a random polymorphic wave sequence should meet the following conditions:

[0009] Connecting the beginning and end to form a loop, and ; The number of states in a random polymorphic wave sequence. for Number of crossings, The modulation depth.

[0010] Design a feedback shift register (LSFR) to generate pseudo-random number sequences. And construct a multi-state selector. Based on the constraints... and Preset modulation sequence library According to the output of the multi-state selector Randomly select the sequence output at the current time. ;

[0011] sequence library , Set to 2 to the power of N;

[0012] No. bar sequence , code element , The set sequence length, which takes the value of 2 to the power of N;

[0013] sequence library Each sequence in the dataset satisfies the constraints. and :

[0014] Consistency constraint between the first and last states: For the sequence Initial state and final state Must meet:

[0015]

[0016] in, This represents the state transition path based on a random polymorphic wave sequence, according to the sequence. symbol sequence transfer The next composite state transition:

[0017] ;

[0018] For code element The direction of state transition, ;

[0019] For the maximum consecutive same-direction jump constraint: sequence The travel length must meet the following requirements:

[0020] ;

[0021] For sequence The set consisting of the lengths of all runs (segments composed of consecutive identical symbols); This is the preset maximum allowable run length.

[0022] Step 2: Based on the sequence Current code value The transition state stores the multi-state modulation signals generated during the transition of the random multi-state modulation state and constructs a time-varying modulation generator matrix. Simultaneously determine the sequence If all code elements have been traversed, proceed to step three; otherwise, return to step two and continue outputting the sequence. The next code ;

[0023] Modulation Generator Matrix The physical essence is a deterministic mapping from discrete digital encoding to continuous optical phase modulation voltage, which specifies how to... The symbol order in the sequence changes the amplitude of the modulation voltage. Its mathematical description is:

[0024]

[0025] The first line block represents the driving code element. The generation path, It is a sequence symbol extraction matrix, whose function is to extract the feature vectors from the sequence library. Extract the code elements that should be output at the current moment. ;

[0026] The second line block represents the update path for the phase state. It is a code element The corresponding random polymorphic wave state transition matrix;

[0027] The third row represents the modulation voltage. The generation path; where It is a diagonal matrix, whose diagonal elements are the discrete phase state values. It is an identity matrix, whose function is to store the state vectors of random polymorphic waves. Convert to voltage ; The half-wave voltage of the modulator. For the bias of the modulation signal, it is generally set to a value of ;

[0028] Step 3: Generate a pseudo-random number sequence based on another LSFR. ,according to Current value Transition state, and simultaneously determine If the output was successful, store the multi-state modulation signal generated during the shift of the random multi-state modulation state, and construct a time-varying modulation generator matrix. Proceed to step two; otherwise, return to step three and re-output. ;

[0029] Modulation Generator Matrix The physical essence and Similarly, for the deterministic mapping from discrete digital codes to continuous optical phase modulation voltages, it is specified how to determine the mapping based on random symbols. Change the amplitude of the modulation voltage. Its mathematical description is:

[0030]

[0031] In the first line block The function is to transform the feature vector of a stochastic process random bits Extracted as driving code elements ;

[0032] The second line block represents the update path for the phase state. It is a code element The corresponding random polymorphic wave state transition matrix;

[0033] The third line block and The meaning of the third line block is consistent.

[0034] Step 4, based on and Constructing a time-varying composite modulation generation matrix The system uniformly represents and outputs the random multimode wave modulation signal. It generates angular velocity demodulation sequences and modulation coefficient demodulation sequences, collects the digital quantities corresponding to the light intensity signals during the movement process of the random multimode wave modulation state, and outputs the angular velocity and modulation coefficients. A crosstalk noise model of the integrated optical gyroscope is established to verify the noise suppression capability of the random multimode wave modulation scheme.

[0035] The composite modulation generation matrix In sequence-based The generated modulation generation matrix and based on pseudo-random numbers The generated modulation generation matrix They switch sequentially; their mathematical description is as follows:

[0036]

[0037] in, It is the system output vector, containing the driving symbols at the current moment. Phase state and modulation voltage ; It is an augmented system state vector, composed of random polymorphic wave state vectors. Sequence library feature vectors and the eigenvectors of a stochastic process constitute; For the demodulation sequence of the first Values.

[0038] According to the driver code By determining the current state's position on the random polymorphic wave state transition path, the modulation depth corresponding to the modulation voltage at the current moment is obtained. Once the modulation depth at each moment is established, the demodulation sequence corresponding to the angular velocity / modulator coefficient can be obtained, thus completing the angular velocity calculation and modulation coefficient error calculation. Based on the calculated angular velocity value, the calculated modulation coefficient error value, and the controller, the angular velocity closed-loop circuit and the modulation coefficient closed-loop circuit are constructed respectively, ultimately completing the construction of the dual closed-loop signal detection circuit.

[0039] The crosstalk noise model is as follows:

[0040]

[0041] in, For crosstalk noise, Noise introduced by capacitive crosstalk, Noise introduced by inductive crosstalk This is the capacitive crosstalk attenuation coefficient. Let be the characteristic impedance at any point on the interference line. The mutual inductance per unit length of the transmission line. The coupling length is... For capacitive noise bias, This is the inductive crosstalk attenuation coefficient. The mutual inductance per unit length of the transmission line, This is for inductive noise bias.

[0042] Correlation between the modulation sequence and the angular velocity demodulation sequence To characterize the impact of crosstalk noise, specifically:

[0043]

[0044] in, For the relevant length;

[0045] For angular velocity demodulation sequence, For digital delay;

[0046] For modulator coefficients, For capacitive crosstalk coefficient, The inductive crosstalk coefficient;

[0047] Modulation voltage The corresponding modulation phase, due to the randomness of the sequence, It has white noise characteristics and an expected value. Therefore Evenly distributed in ;

[0048] Then at this point we have:

[0049]

[0050] Therefore, the modulation scheme proposed in this invention constructs a system that satisfies the constraints. and By employing a random polymorphic wave state transition path, a specific random polymorphic wave modulation signal is generated, thereby randomizing the modulation voltage and imbuing it with white noise characteristics, thus suppressing the mean crosstalk noise to zero. This method effectively suppresses crosstalk noise introduced by high modulation frequencies in integrated optical gyroscopes, ultimately reducing the gyroscope's dead zone.

[0051] The advantages of this invention are:

[0052] This invention discloses a random multi-state wave modulation method for an interferometric integrated optical gyroscope. It considers the significant crosstalk noise in the integrated optical gyroscope and achieves decorrelation of crosstalk noise by designing a random multi-state wave modulation scheme. Simultaneously, it considers the maximum allowable run length to limit the demodulation period range of the signal detection scheme, ensuring closed-loop dynamic performance. This provides an effective signal detection method for integrated optical gyroscopes. Attached Figure Description

[0053] Figure 1 This is a flowchart of a random multi-state wave modulation method for an interferometric integrated optical gyroscope according to the present invention;

[0054] Figure 2 This is a comparison diagram of crosstalk noise in the prototype test of an embodiment of the present invention;

[0055] Figure 3 This is a schematic diagram comparing the simulated run lengths in an embodiment of the present invention;

[0056] Figure 4 This is a comparison chart of the prototype test accuracy of an embodiment of the present invention. Detailed Implementation

[0057] To facilitate understanding and implementation of the present invention by those skilled in the art, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Obviously, the described embodiments are merely some, not all, embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort should fall within the scope of protection of the present invention.

[0058] This invention addresses the significant crosstalk noise in integrated optical gyroscopes and the long closed-loop period of simple random schemes by designing a random multi-mode wave modulation scheme with a switching strategy. Based on a modulation sequence library, random variables, and state transition paths that meet specific constraints, a random multi-mode wave modulation voltage is constructed. Based on the mapping relationship, the demodulation sequence is obtained, the angular velocity / modulation coefficient is calculated, and a dual closed-loop system is constructed to realize this random multi-mode wave modulation method, ensuring closed-loop dynamic performance while suppressing crosstalk noise.

[0059] This scheme constructs a finite-length digital sequence modulation library and designs a multi-state selector based on LFSR sequences to select specific sequences and store them in a random state memory; simultaneously, another pseudo-random sequence is output and stored in another random state memory. A random polymorphic wave state transition path is established, and by combining the sequence library, selector, and memory, a time-varying composite modulation generation matrix is ​​used to uniformly generate driving symbols, phase states, and output voltages, outputting a random modulated polymorphic wave signal. Based on the characteristics of the modulation sequence, a synchronous demodulation sequence is generated through pre-stored mapping, and a dual closed-loop system is constructed by combining the angular velocity and modulation coefficient calculation values. Finally, an integrated optical gyroscope crosstalk noise model is established, and the effectiveness of the scheme is verified through mathematical reasoning. This method effectively achieves statistical decorrelation of modulation and demodulation, suppresses short waveguide crosstalk noise, overcomes the problem of excessively long demodulation periods in traditional random modulation, improves the accuracy of integrated optical gyroscopes, reduces dead zone range, and enhances operational stability, thus possessing significant practical value.

[0060] The random multi-state wave modulation method of the interferometric integrated optical gyroscope, such as Figure 1 As shown, the specific steps are as follows:

[0061] Step 1: While integrating optical gyroscopes increases integration density by compressing the interference loop length, it significantly increases the modulation frequency, inevitably introducing crosstalk noise. A random polymorphic wave sequence state transition path is designed. By generating a random polymorphic wave modulation sequence, the modulation voltage is randomized, giving it white noise characteristics. This results in a crosstalk noise mean of 0, effectively reducing crosstalk noise and thus decreasing the dead zone width.

[0062] The state transition path of a random polymorphic wave sequence should meet the following conditions:

[0063] Connecting the beginning and end to form a loop, and ; The number of states in a random polymorphic wave sequence. for Number of crossings, The modulation depth.

[0064] Design a feedback shift register (LSFR) to generate pseudo-random number sequences. And construct a multi-state selector. Based on the constraints... and Preset modulation sequence library According to the output of the multi-state selector Randomly select the sequence output at the current time. ;

[0065] sequence library , Set to 2 to the power of N;

[0066] No. bar sequence , code element , The set sequence length, which takes the value of 2 to the power of N;

[0067] sequence library Each sequence in the dataset satisfies the constraints. and :

[0068] Consistency constraint between the first and last states: For the sequence Initial state and final state Must meet:

[0069]

[0070] in, This represents the state transition path based on a random polymorphic wave sequence, according to the sequence. symbol sequence transfer The next composite state transition:

[0071] ;

[0072] For code element The direction of state transition, ;

[0073] For the maximum consecutive same-direction jump constraint: sequence The travel length must meet the following requirements:

[0074] ;

[0075] For sequence The set consisting of the lengths of all runs (segments composed of consecutive identical symbols); This is the preset maximum allowable run length.

[0076] Step 2: Based on the sequence Current code value The transition state stores the multi-state modulation signals generated during the transition of the random multi-state modulation state and constructs a time-varying modulation generator matrix. Simultaneously determine the sequence If all code elements have been traversed, proceed to step three; otherwise, return to step two and continue outputting the sequence. The next code ;

[0077] Modulation Generator Matrix The physical essence is a deterministic mapping from discrete digital encoding to continuous optical phase modulation voltage, which specifies how to... The symbol order in the sequence changes the amplitude of the modulation voltage. Its mathematical description is:

[0078]

[0079] The first line block represents the driving code element. The generation path, It is a sequence symbol extraction matrix, whose function is to extract the feature vectors from the sequence library. Extract the code elements that should be output at the current moment. ;

[0080] The second line block represents the update path for the phase state. It is a code element The corresponding random polymorphic wave state transition matrix;

[0081] The third row represents the modulation voltage. The generation path; where It is a diagonal matrix, whose diagonal elements are the discrete phase state values. It is an identity matrix, whose function is to store the state vectors of random polymorphic waves. Convert to voltage ; The half-wave voltage of the modulator. For the bias of the modulation signal, it is generally set to a value of ;

[0082] Step 3: Generate a pseudo-random number sequence based on another LSFR. ,according to Current value Transition state, and simultaneously determine If the output was successful, store the multi-state modulation signal generated during the shift of the random multi-state modulation state, and construct a time-varying modulation generator matrix. Proceed to step two; otherwise, return to step three and re-output. ;

[0083] Modulation Generator Matrix The physical essence and Similarly, for the deterministic mapping from discrete digital codes to continuous optical phase modulation voltages, it is specified how to determine the mapping based on random symbols. Change the amplitude of the modulation voltage. Its mathematical description is:

[0084]

[0085] In the first line block The function is to transform the feature vector of a stochastic process random bits Extracted as driving code elements ;

[0086] The second line block represents the update path for the phase state. It is a code element The corresponding random polymorphic wave state transition matrix;

[0087] The third line block and The meaning of the third line block is consistent.

[0088] Step 4, based on and Constructing a time-varying composite modulation generation matrix The system uniformly represents and outputs the random multimode wave modulation signal. It generates angular velocity demodulation sequences and modulation coefficient demodulation sequences, collects the digital quantities corresponding to the light intensity signals during the movement process of the random multimode wave modulation state, and outputs the angular velocity and modulation coefficients. A crosstalk noise model of the integrated optical gyroscope is established to verify the noise suppression capability of the random multimode wave modulation scheme.

[0089] The composite modulation generation matrix In sequence-based The generated modulation generation matrix and based on pseudo-random numbers The generated modulation generation matrix They switch sequentially; their mathematical description is as follows:

[0090]

[0091] in, It is the system output vector, containing the driving symbols at the current moment. Phase state and modulation voltage ; It is an augmented system state vector, composed of random polymorphic wave state vectors. Sequence library feature vectors and the eigenvectors of a stochastic process constitute; For the demodulation sequence of the first Values.

[0092] According to the driver code By determining the current state's position on the random polymorphic wave state transition path, the modulation depth corresponding to the modulation voltage at the current moment is obtained. Once the modulation depth at each moment is established, the demodulation sequence corresponding to the angular velocity / modulator coefficient can be obtained, thus completing the angular velocity calculation and modulation coefficient error calculation. Based on the calculated angular velocity value, the calculated modulation coefficient error value, and the controller, the angular velocity closed-loop circuit and the modulation coefficient closed-loop circuit are constructed respectively, ultimately completing the construction of the dual closed-loop signal detection circuit.

[0093] The crosstalk noise model is as follows:

[0094]

[0095] in, For crosstalk noise, Noise introduced by capacitive crosstalk, Noise introduced by inductive crosstalk This is the capacitive crosstalk attenuation coefficient. Let be the characteristic impedance at any point on the interference line. The mutual inductance per unit length of the transmission line. The coupling length is... For capacitive noise bias, This is the inductive crosstalk attenuation coefficient. The mutual inductance per unit length of the transmission line, This is for inductive noise bias.

[0096] Correlation between the modulation sequence and the angular velocity demodulation sequence To characterize the impact of crosstalk noise, specifically:

[0097]

[0098] in, For the relevant length;

[0099] For angular velocity demodulation sequence, For digital delay;

[0100] For modulator coefficients, For capacitive crosstalk coefficient, The inductive crosstalk coefficient;

[0101] Modulation voltage The corresponding modulation phase, due to the randomness of the sequence, It has white noise characteristics and an expected value. Therefore Evenly distributed in ;

[0102] Then at this point we have:

[0103]

[0104] Therefore, the modulation scheme proposed in this invention constructs a system that satisfies the constraints. and By employing a random polymorphic wave state transition path, a specific random polymorphic wave modulation signal is generated, thereby randomizing the modulation voltage and imbuing it with white noise characteristics, thus suppressing the mean crosstalk noise to zero. This method effectively suppresses crosstalk noise introduced by high modulation frequencies in integrated optical gyroscopes, ultimately reducing the gyroscope's dead zone. Example

[0105] The specific steps of the random multi-state wave modulation method for the interferometric integrated optical gyroscope are as follows:

[0106] Step 1: While integrating optical gyroscopes increases integration density by compressing the interference loop length, it significantly increases the modulation frequency, inevitably introducing crosstalk noise. A random polymorphic wave sequence state transition path is designed. By generating a random polymorphic wave modulation sequence, the modulation voltage is randomized, giving it white noise characteristics. This results in a crosstalk noise mean of 0, effectively reducing crosstalk noise and thus decreasing the dead zone width. A feedback shift register (LSFR) is designed to generate a pseudo-random number sequence. And construct a multi-state selector. Based on the constraints... and Preset modulation sequence library According to the output of the multi-state selector Randomly select the sequence output at the current time. ;

[0107] Among them, sequence library , Set to 2 to the power of N; the Nth bar sequence , code element , The set sequence length, which takes the value of 2 to the power of N;

[0108] sequence library Each sequence in the sequence satisfies the constraints. and :

[0109] Consistency constraint between the first and last states: For the sequence Initial state and final state Must meet:

[0110] ;

[0111] in, This represents the state transition path based on a random polymorphic wave sequence, according to the sequence. symbol sequence transfer Multiple composite state transitions;

[0112] For the maximum consecutive same-direction jump constraint: sequence The travel length must meet the following requirements:

[0113] ;

[0114] For sequence The set consisting of the lengths of all runs in the sequence; This is the preset maximum allowable run length;

[0115] Step 2: Based on the sequence Current code value The transition state stores the multi-state modulation signals generated during the transition of the random multi-state modulation state and constructs a time-varying modulation generator matrix. Simultaneously determine the sequence If all code elements have been traversed, proceed to step three; otherwise, return to step two and continue outputting the sequence. The next code ;

[0116] Step 3: Generate a pseudo-random number sequence based on another LSFR. ,according to Current value Transition state, and simultaneously determine If the output was successful, store the multi-state modulation signal generated during the shift of the random multi-state modulation state, and construct a time-varying modulation generator matrix. Proceed to step two; otherwise, return to step three and re-output. ;

[0117] Step 4, based on and Constructing a time-varying composite modulation generation matrix The system uniformly represents and outputs the random multimode wave modulation signal. It generates angular velocity demodulation sequences and modulation coefficient demodulation sequences, collects the digital quantities corresponding to the light intensity signals during the movement process of the random multimode wave modulation state, and outputs the angular velocity and modulation coefficients. A crosstalk noise model of the integrated optical gyroscope is established to verify the noise suppression capability of the random multimode wave modulation scheme.

[0118] The specific method is as follows:

[0119] For the state transition path of the random multi-state wave modulation, an optimal value is selected, with a modulation depth of 3. / 4, at this point, the number of states m=8, the number of crossings n=3, and the eight states are (0,3). / 4,3 / 2, / 4, 7 / 4, / 2,5 / 4), these eight states form a closed loop.

[0120] In building the sequence library, a preferred value is preset: The primitive equation for generating random number b using a 40th-order LFSR is: .

[0121] An integrated optical gyroscope was chosen as the main research subject. The light source was turned off to isolate the influence of the optical path. The interference signal S(n) generated by the optical path was then 0, and the gyroscope output consisted of electronic crosstalk noise. Assuming the gyroscope integration time was t, the system output at this time was:

[0122]

[0123] in, This refers to the gain of the preamplifier circuit. For A / D converter gain, To demodulate the gain, For controllers. The correlation results between the error phase shift caused by crosstalk and the demodulated sequence; This is circuit noise. Keeping the experimental system conditions constant, the parameters are as follows: This can be considered constant. At this point, the output value has an approximately linear relationship with time, and the slope is related to the crosstalk magnitude, which can characterize the crosstalk of the entire circuit. Different modulation schemes were tested, with each modulation scheme recorded for ten minutes. The test results are as follows: Figure 2 As shown in the figure, it can be seen that, compared with traditional modulation, the present invention has a stronger ability to suppress crosstalk noise.

[0124] Based on Matlab, simple random modulation waveforms and the random multi-state modulation waveforms of this invention were simulated and generated respectively. The number of runs for each step was counted, and the test results are as follows: Figure 3 As shown, compared with traditional modulation, the present invention has a shorter modulation period and excellent closed-loop performance.

[0125] Based on an integrated optical gyroscope, different modulation methods were selected, and the modulation voltage / proportional-integral controller parameters were appropriately set. The angular velocity output of the integrated optical gyroscope under traditional square wave modulation and random multi-state wave modulation of the present invention were measured respectively. The accuracy of the two was compared, and the test results are as follows: Figure 4 As shown, the precision of traditional modulation is 0.1044. The accuracy of random polymorphic wave modulation is 0.05962. It can be seen that, compared with traditional modulation schemes, the present invention has better measurement accuracy.

Claims

1. A method for random multi-state wave modulation of an interferometric integrated optical gyroscope, characterized in that, In response to the scenario where integrated optical gyroscopes significantly increase modulation frequency and introduce crosstalk noise while improving integration by compressing interference loop length, this invention designs a random polymorphic wave sequence state transition path. By generating a random polymorphic wave modulation sequence, the modulation voltage is randomized, giving it white noise characteristics and making the mean crosstalk noise 0. The specific steps are as follows: Step 1: Design a feedback shift register (LSFR) to generate a pseudo-random number sequence. And construct a multi-state selector based on the constraints. and Preset modulation sequence library According to the output of the multi-state selector Randomly select the sequence output at the current time. ; Among them, sequence library , Set to 2 to the power of N; the Nth bar sequence , code element , The set sequence length, which takes the value of 2 to the power of N; sequence library Each sequence in the sequence satisfies the constraints. and : Consistency constraint between the first and last states: For the sequence Initial state and final state Must meet: ； in, This represents the state transition path based on a random polymorphic wave sequence, according to the sequence. symbol sequence transfer Multiple composite state transitions; For the maximum consecutive same-direction jump constraint: sequence The travel length must meet the following requirements: ； For sequence The set consisting of the lengths of all runs in the sequence; This is the preset maximum allowable run length; Step 2: Based on the sequence Current code value The transition state stores the multi-state modulation signals generated during the transition of the random multi-state modulation state and constructs a time-varying modulation generator matrix. Simultaneously determine the sequence Have all the code elements been traversed? If so, proceed to step three; otherwise, continue outputting the sequence. The next code ; Step 3: Generate a pseudo-random number sequence based on another LSFR. According to the current value Transition state, and simultaneously determine If the output was successful, store the multi-state modulation signal generated during the shift of the random multi-state modulation state, and construct a time-varying modulation generator matrix. Proceed to step two; otherwise, re-output. ; Step 4: Based on the modulation generation matrix and Constructing a time-varying composite modulation generation matrix The system uniformly represents and outputs the random polymorphic wave modulation signal; the generated angular velocity demodulation sequence and modulation coefficient demodulation sequence are used to collect the digital quantities corresponding to the light intensity signal during the movement process of the random polymorphic wave modulation state, and output the angular velocity and modulation coefficient; a crosstalk noise model of the integrated optical gyroscope is established to verify the noise suppression capability of the random polymorphic wave modulation scheme.

2. The method as described in claim 1, characterized in that, In step one, the state transition path of the random polymorphic wave sequence should meet the following conditions: Connecting the beginning and end to form a loop, and ; The number of states in a random polymorphic wave sequence. for Number of crossings, The modulation depth.

3. The method as described in claim 1, characterized in that, The constraints of step one middle, ； For code element The direction of state transition, .

4. The method as described in claim 1, characterized in that, In step two, the modulation generation matrix is... The physical essence is a deterministic mapping from discrete digital encoding to continuous optical phase modulation voltage, which specifies how to... The symbol order of the sequence changes the amplitude of the modulation voltage; its mathematical description is: The first line block represents the driving code element. The generation path, It is a sequence symbol extraction matrix, whose function is to extract the feature vectors from the sequence library. Extract the code elements that should be output at the current moment. ; The second line block represents the update path for the phase state. It is a code element The corresponding random polymorphic wave state transition matrix; The third row represents the modulation voltage. The generation path; where It is a diagonal matrix, whose diagonal elements are the discrete phase state values. It is an identity matrix, whose function is to store the state vectors of random polymorphic waves. Convert to voltage ; The half-wave voltage of the modulator. For the bias of the modulation signal, it is generally set to a value of .

5. The method as described in claim 4, characterized in that, In step three, the modulation generation matrix is... The physical essence and Similarly, for the deterministic mapping from discrete digital codes to continuous optical phase modulation voltages, it is specified how to determine the mapping based on random symbols. The amplitude of the modulation voltage is changed; its mathematical description is as follows: In the first line block The function is to transform the feature vector of a stochastic process random bits Extracted as driving code elements ; The second line block represents the update path for the phase state. It is a code element The corresponding random polymorphic wave state transition matrix; The third line block and The meaning of the third line block is consistent.

6. The method as described in claim 4 or 5, characterized in that, In step four, the composite modulation generation matrix In sequence-based The generated modulation generation matrix and based on pseudo-random numbers The generated modulation generation matrix They switch sequentially; their mathematical description is as follows: in, It is the system output vector, containing the driving symbols at the current moment. Phase state and modulation voltage ; It is an augmented system state vector, composed of random polymorphic wave state vectors. Sequence library feature vectors and the eigenvectors of a stochastic process constitute; For the demodulation sequence of the first Values.

7. The method as described in claim 6, characterized in that, In step four, based on the driving code elements And the position of the current state on the state transition path of the random polymorphic wave, to know the modulation depth corresponding to the modulation voltage at the current moment, and to establish the modulation depth at each moment, the demodulation sequence corresponding to the angular velocity / modulator coefficient can be obtained, and the angular velocity calculation and modulation coefficient error calculation can be completed. Based on the calculated angular velocity value, the calculated modulation coefficient error value, and the controller, an angular velocity closed-loop circuit and a modulation coefficient closed-loop circuit are constructed respectively, and finally the construction of a dual closed-loop signal detection circuit is completed.

8. The method as described in claim 5, characterized in that, In step four, the crosstalk noise model is as follows: in, For modulation voltage, For crosstalk noise, Noise introduced by capacitive crosstalk, Noise introduced by inductive crosstalk This is the capacitive crosstalk attenuation coefficient. Let be the characteristic impedance at any point on the interference line. The mutual inductance per unit length of the transmission line. The coupling length is... For capacitive noise bias, This is the inductive crosstalk attenuation coefficient. The mutual inductance per unit length of the transmission line, For inductive noise bias; Crosstalk noise participates in demodulation as an error voltage; therefore, the correlation between the modulation sequence and the angular velocity demodulation sequence is used. To characterize the impact of crosstalk noise, specifically: in, For the relevant length; For angular velocity demodulation sequence, For digital delay; For modulator coefficients, For capacitive crosstalk coefficient, The inductive crosstalk coefficient; Modulation voltage The corresponding modulation phase, due to the randomness of the sequence, It has white noise characteristics and an expected value. Therefore Evenly distributed in ; The demodulated sequence is composed of the modulation phase difference. Decide; Then at this point we have: Therefore, this modulation scheme, by constructing a system that satisfies the constraints... and The random polymorphic wave state transition path generates a specific random polymorphic wave modulation signal, realizes the randomization of the modulation voltage, and makes it have white noise characteristics, thereby suppressing the mean crosstalk noise to 0.

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