A BeiDou dual-frequency INS vector depth integrated navigation method and system

Abstract

This invention provides a BeiDou dual-frequency INS vector depth integrated navigation method and system, comprising: calculating the measured pseudorange and pseudorange rate using the BeiDou signal identification result output by the correlator and the pseudorange rate of the BeiDou tracking channel after dual-frequency ionospheric correction; using the pseudorange error between the predicted position calculated pseudorange and the measured pseudorange, and the pseudorange rate error between the predicted velocity calculated pseudorange rate and the measured pseudorange rate as quantitative inputs to the integrated navigation filter to update the state variables and feed them back to the INS system to correct the navigation parameters; calculating the code phase and carrier frequency correction amounts for BeiDou signal tracking based on the corrected navigation information and ephemeris information to drive the code and carrier numerically controlled oscillators, wherein during the navigation update interval, the code and carrier numerically controlled oscillators are updated using the carrier frequency change rate calculated by the INS system navigation results.

Description

Technical Field

[0001] This invention relates to the field of BeiDou navigation technology, and in particular to a BeiDou dual-frequency INS vector depth combined navigation method and system. Background Technology

[0002] In open environments with good observation conditions, the receiver can continuously receive satellite signals. However, in situations with obstructions such as tree-lined roads, tall buildings in canyons, overpasses, or tunnels, or where the carrier is highly dynamic, the satellite receiver's tracking loop is prone to lock-up or failure to receive satellite signals normally, resulting in a loss of positioning continuity and availability. INS-assisted vector depth integration technology can significantly improve tracking accuracy, sensitivity, and continuity.

[0003] Current vector depth integrated navigation technologies mostly combine GPS or BeiDou B1I signals based on single frequencies with INS. Due to the limited observation data, this combination method cannot eliminate ionospheric errors through simultaneous equations, and the frequencies used are shared by multiple GNSS systems, making them susceptible to interference and deception. However, B1I and B3I are unique to BeiDou and do not overlap with other navigation systems, naturally possessing anti-interference advantages and playing an important role in national defense and critical national infrastructure applications. Therefore, this invention proposes a BeiDou dual-frequency INS vector depth integrated navigation algorithm using a single BeiDou mode to solve the problems of poor tracking continuity and slow reacquisition speed of BeiDou B1I and B3I signals in complex environments and high dynamic situations, while also possessing high integrated navigation accuracy and a certain degree of anti-interference capability. Summary of the Invention

[0004] This invention provides a BeiDou dual-frequency INS vector depth combined navigation method and system to overcome the deficiencies in the existing technology.

[0005] In a first aspect, the present invention provides a BeiDou dual-frequency INS vector depth integrated navigation method, comprising: The B1I and B3I satellite signals are correlated with the local signals generated by the carrier NCO and code NCO to obtain the discrimination error. Calculate pseudorange and pseudorange rate using satellite signal propagation time and Doppler frequency shift; Subtract the pseudorange and pseudorange rate from the pseudorange error and pseudorange rate error calculated using the discrimination error, respectively, to obtain the pseudorange measurement value and pseudorange rate measurement value; The position and velocity of the carrier are obtained by solving the inertial navigation data, the position and velocity of each satellite are obtained by analyzing the ephemeris, and the pseudorange and pseudorange rate are obtained by using the position and velocity of the satellites and the carrier. The pseudorange calculation value and pseudorange rate calculation value are subtracted from the pseudorange measurement value and pseudorange rate measurement value, respectively, to obtain the pseudorange error measurement value and pseudorange rate error measurement value. The pseudorange error measurement value and pseudorange rate error measurement value are input into the integrated navigation filter to update the navigation error state variable, and the navigation error parameters are fed back to the INS system to correct the navigation parameters. The carrier frequency change rate and code phase and carrier frequency correction amount are estimated using the corrected navigation parameters and ephemeris information to control the pseudocode and carrier NCO, maintain tracking of the input signal, and repeat the above steps.

[0006] According to the present invention, a BeiDou dual-frequency INS vector depth integrated navigation method correlates B1I satellite signals and B3I satellite signals with local signals generated by carrier NCO and code NCO to obtain discrimination error, including: B1I satellite signals and B3I satellite signals are :

[0007] Local signals generated by carrier NCO and code NCO :

[0008] The correlation value is the sum of the product of the received signal and the locally replicated signal within the integral. :

[0009] Obtain the error of the code detector error of carrier frequency discriminator ; in, The interval between early and late chips, For signal power, For modulated data, This is pseudocode. The sampling interval is... For data indexing, For carrier frequency offset, For noise terms, This refers to the code phase offset time. For carrier phase offset, This is the cumulative number of sampling points. and These are the in-phase and quadrature components of the advance code correlation value, respectively. and These are the in-phase and quadrature components of the correlation value of the hysteresis code, respectively. For cross power, This represents the dot product power.

[0010] According to the present invention, a BeiDou dual-frequency INS vector depth integrated navigation method is provided, which calculates pseudorange and pseudorange rate using satellite signal propagation time and Doppler frequency shift, including: Calculate the satellite signal propagation time based on the received signal code phase, and calculate the code pseudorange. ; The ionospheric delay effect is corrected using a dual-frequency B1I / B3I de-ionization pseudorange formula. The Doppler frequency shift is obtained by subtracting the intermediate frequency signal frequency from the carrier frequency, and the pseudorange rate is calculated. ;

[0011] in, It is the pseudorange corrected for ionosphere. and These are the observed pseudoranges of the B1I and B3I signals. It is the on-board equipment delay difference of the B1I signal. It's the speed of light. This represents the ionospheric delay scaling factor between the B1I and B3I frequency points. ,in For frequency variables.

[0012] According to the present invention, a BeiDou dual-frequency INS vector depth integrated navigation method is provided, which subtracts the pseudorange and pseudorange rate from the pseudorange error and pseudorange rate error calculated using the discrimination error, respectively, to obtain the pseudorange measurement value and pseudorange rate measurement value, including:

[0013]

[0014] in, Indicates the pseudorange measurement value. This represents the pseudorange rate measurement value. For pseudocode wavelength, Indicates the carrier wavelength. and These represent the code phase error and carrier frequency error within the measurement period, respectively.

[0015] According to the present invention, a BeiDou dual-frequency INS vector depth integrated navigation method is provided, which calculates the position and velocity of the carrier by solving inertial navigation data, calculates the position and velocity of each satellite by analyzing ephemeris data, and obtains pseudorange and pseudorange rate calculation values ​​using the position and velocity of the satellites and the carrier. The position and velocity of the carrier are obtained by solving the inertial navigation data using a strapdown inertial navigation algorithm; The navigation message is analyzed to obtain ephemeris parameters, and the position and velocity of each tracked satellite are calculated using the ephemeris parameters. The pseudorange is calculated using the position and velocity of the satellite and the carrier. and pseudorange rate calculation value .

[0016] According to the BeiDou dual-frequency INS vector depth integrated navigation method provided by the present invention, the pseudorange calculation value and pseudorange rate calculation value are subtracted from the pseudorange measurement value and pseudorange rate measurement value, respectively, to obtain the pseudorange error measurement value and pseudorange rate error measurement value. The pseudorange error measurement value and pseudorange rate error measurement value are input into the integrated navigation filter to update the navigation error state variable, and the navigation error parameters are fed back to the INS system to correct the navigation parameters, including: pseudorange calculation value and pseudorange rate calculation value , respectively with pseudorange measurement values and pseudorange rate measurement The pseudorange error measurement and pseudorange rate error measurement obtained by subtraction are input into the integrated navigation filter, and the vector depth combined state variable is selected as the location under the geographic system. and speed error Attitude misalignment angle Clock error Three-axis gyroscope Zero bias of accelerometer ,Right now The system's state equation is the inertial navigation error propagation equation. ; in:

[0017] The antisymmetric matrix representing the relative forces in the geographic coordinate system. This represents the direction cosine matrix from the body coordinate system to the geographic coordinate system. For accelerometer output noise, To reduce noise output from the gyroscope. For receiver clock error driving noise, and Zero-bias drive noise for accelerometers and gyroscopes; The measurement equation is:

[0018] For satellite The line-of-sight vector between the carrier and the target. The navigation error state variables are updated, and the estimated navigation error parameters are fed back to the INS system to correct the navigation parameters.

[0019] The present invention provides a BeiDou dual-frequency INS vector depth integrated navigation method, which uses corrected navigation parameters and ephemeris information to estimate the carrier frequency change rate and code phase and carrier frequency correction amount to control the pseudocode and carrier NCO, and maintain tracking of the input signal, including: The vehicle motion state is recalculated using the corrected navigation parameter state variables, and the carrier frequency change rate is estimated. ,in Let be the relative acceleration between the carrier and the satellite, where is the acceleration between the carrier and the satellite. and These represent the acceleration vectors of the satellite and the receiver, respectively. and These represent the velocity vectors of the satellite and the receiver, respectively. and These represent the position vectors of the satellite and the receiver, respectively. Indicates the distance between the satellite and the receiver; Obtain code phase correction amount With carrier frequency correction To control the pseudocode and carrier NCO, and maintain tracking of the input signal. For the carrier digitally controlled oscillator frequency, This indicates the intermediate frequency of the signal.

[0020] Secondly, the present invention also provides a BeiDou dual-frequency INS vector depth integrated navigation system, comprising: The first calculation module is used to correlate the B1I satellite signal and the B3I satellite signal with the local signal generated by the carrier NCO and the code NCO to obtain the discrimination error; The second calculation module is used to calculate pseudorange and pseudorange rate using satellite signal propagation time and Doppler frequency shift; The third calculation module is used to subtract the pseudorange and pseudorange rate from the pseudorange error and pseudorange rate error calculated using the discrimination error, respectively, to obtain the pseudorange measurement value and pseudorange rate measurement value. The fourth calculation module is used to solve the inertial navigation data to obtain the position and velocity of the carrier, analyze the ephemeris to calculate the position and velocity of each satellite, and use the position and velocity of the satellites and the carrier to obtain the pseudorange calculation value and pseudorange rate calculation value. The fifth calculation module is used to subtract the pseudorange calculation value and pseudorange rate calculation value from the pseudorange measurement value and pseudorange rate measurement value, respectively, to obtain the pseudorange error measurement value and pseudorange rate error measurement value. The pseudorange error measurement value and pseudorange rate error measurement value are then input into the integrated navigation filter to update the navigation error state variable, and the navigation error parameters are fed back to the INS system to correct the navigation parameters. The sixth calculation module is used to estimate the carrier frequency change rate and code phase and carrier frequency correction amount using the corrected navigation parameters and ephemeris information, so as to control the pseudo code and carrier NCO, maintain tracking of the input signal, and repeat the above steps.

[0021] Thirdly, the present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the BeiDou dual-frequency INS vector depth combined navigation method as described above.

[0022] Fourthly, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the BeiDou dual-frequency INS vector depth combined navigation method as described above.

[0023] The BeiDou dual-frequency INS vector depth integrated navigation method and system provided by this invention have the following advantages: (1) Focus on the frequency combination within the BeiDou system, fully explore the potential of the BeiDou system itself, and integrate IMU data into the tracking loop of BeiDou B1I and B3I signals; (2) The vector tracking method can use the information of the strong signal channel to assist the tracking of the weak signal channel loop, and can continuously track more visible satellites in complex environments; (3) By using IMU to assist in carrier frequency prediction, the loop is less likely to lose lock under high dynamic conditions of the carrier. Even if the signal is lost in a short-term full-coverage scenario, the acquisition and positioning calculation can be completed quickly after the signal reappears. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0025] Figure 1 This is a flowchart illustrating the BeiDou dual-frequency INS vector depth combined navigation method provided by the present invention; Figure 2 This is a diagram of the BeiDou dual-frequency INS vector deep combination structure provided by the present invention; Figure 3 This is a block diagram of the implementation of BeiDou dual-frequency INS vector deep combination provided by the present invention; Figure 4 This is a schematic diagram of the structure of the Beidou dual-frequency INS vector depth combined navigation system provided by the present invention; Figure 5This is a schematic diagram of the structure of the electronic device provided by the present invention. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0027] Figure 1 This is a flowchart illustrating the BeiDou dual-frequency INS vector depth integrated navigation method provided in an embodiment of the present invention, as shown below. Figure 1 As shown, it includes: Step 100: Correlate the B1I satellite signal and the B3I satellite signal with the local signal generated by the carrier NCO and the code NCO to obtain the discrimination error; Step 200: Calculate pseudorange and pseudorange rate using satellite signal propagation time and Doppler frequency shift; Step 300: Subtract the pseudorange and pseudorange rate from the pseudorange error and pseudorange rate error calculated using the discrimination error, respectively, to obtain the pseudorange measurement value and pseudorange rate measurement value; Step 400: Solve the inertial navigation data to obtain the position and velocity of the carrier, analyze the ephemeris to obtain the position and velocity of each satellite, and use the position and velocity of the satellites and the carrier to obtain the pseudorange calculation value and pseudorange rate calculation value. Step 500: Subtract the pseudorange calculation value and pseudorange rate calculation value from the pseudorange measurement value and pseudorange rate measurement value, respectively, to obtain the pseudorange error measurement value and pseudorange rate error measurement value. Input the pseudorange error measurement value and pseudorange rate error measurement value into the integrated navigation filter to update the navigation error state variable, and feed the navigation error parameters back to the INS system to correct the navigation parameters. Step 600: Use the corrected navigation parameters and ephemeris information to estimate the carrier frequency change rate and the code phase and carrier frequency correction amount to control the pseudocode and carrier NCO, maintain tracking of the input signal, and repeat the above steps.

[0028] Specifically, such as Figure 2As shown, in this embodiment of the invention, the pseudorange and pseudorange rate of the BeiDou tracking channel are calculated using the BeiDou signal identification result output by the correlator and the pseudorange rate of the BeiDou tracking channel after dual-frequency ionospheric correction. The pseudorange error between the pseudorange calculated by the predicted position and the measured pseudorange, and the pseudorange rate error between the pseudorange rate calculated by the predicted velocity and the measured pseudorange rate are used as quantitative inputs to the combined navigation filter to update the state variables and feed them back to the INS system to correct the navigation parameters. The code phase and carrier frequency correction amounts for BeiDou signal tracking are calculated based on the corrected navigation information and ephemeris information to drive the code and carrier numerically controlled oscillator. During the navigation update interval, the code and carrier numerically controlled oscillator is updated using the carrier frequency change rate calculated by the navigation results of the INS system.

[0029] This invention improves the continuous loop tracking performance, rapid reacquisition performance, and high-precision positioning performance of BeiDou B1I and B3I signals in complex environments and high dynamic situations by considering the joint vector loop tracking method of single BeiDou dual-frequency signal and strapdown inertial navigation (INS), deep combination positioning method, and dual-frequency ionospheric error elimination method of BeiDou receiver navigation, while also possessing a certain anti-interference capability.

[0030] Based on the above embodiments, such as Figure 3 As shown, the specific implementation steps of this embodiment of the invention include: Step 1: The BeiDou B1I or B3I signal receiving model acquired by the radio frequency front end is as follows: The locally generated signal model is: The correlation value is the sum of the product of the received signal and the locally replicated signal within the interval between integrations: The error of the phase detector is obtained. error of carrier frequency discriminator .

[0031] in, The interval between early and late chips, For signal power, For modulated data, This is pseudocode. The sampling interval is... For data indexing, For carrier frequency offset, For noise terms, This refers to the code phase offset time. For carrier phase offset, This is the cumulative number of sampling points. and These are the in-phase and quadrature components of the advance code correlation value, respectively. and These are the in-phase and quadrature components of the correlation value of the hysteresis code, respectively. For cross power, This represents the dot product power.

[0032] Step 2: Calculate the satellite signal propagation time based on the received signal code phase, and calculate the code pseudorange accordingly. A dual-frequency B1I / B3I pseudorange formula is used to correct the ionospheric delay effect. The Doppler frequency shift is obtained by subtracting the intermediate frequency signal frequency from the carrier frequency, and the pseudorange rate is calculated accordingly. . It is the pseudorange corrected for ionosphere; and These are the observation pseudoranges of B1I and B3I signals (corrected by satellite clock bias but not yet...). correction); It is the on-board equipment delay difference of the B1I signal; where It's the speed of light.

[0033]

[0034] This represents the ionospheric delay scaling factor between the B1I and B3I frequency points. ,in For frequency variables.

[0035] Step 3: Within one pseudorange and pseudorange rate measurement period, the code phase detector and carrier frequency detector output values ​​are used to remove code phase error and carrier frequency error to reduce measurement noise. That is, the pseudorange measurement value is: ,in The pseudo-code wavelength. The pseudorange rate measurement value is: . Indicates the carrier wavelength. and This represents the code phase error and carrier frequency error within the measurement period.

[0036] Step 4: Use the strapdown inertial navigation algorithm to solve the inertial navigation data to obtain the position and velocity of the vehicle; parse the navigation message to obtain ephemeris parameters, and use the ephemeris parameters to calculate the position and velocity of each tracked satellite; use the position and velocity of the satellites and the vehicle to obtain the calculated values ​​of pseudorange and pseudorange rate. and .

[0037] Step 5: Calculate the pseudorange and pseudorange rate values. and With pseudorange rate measurement and The pseudorange and pseudorange rate error measurements obtained by subtraction are input into the navigation filter. The vector depth combined state variables are selected as position and velocity errors, attitude misalignment angles, clock errors, and zero bias of the three-axis gyroscope and accelerometer in the geographic system. The system's state equation is the inertial navigation error propagation equation: .

[0038] in:

[0039] The antisymmetric matrix representing the relative forces in the geographic coordinate system. This represents the direction cosine matrix from the body coordinate system to the geographic coordinate system.

[0040] In the formula, For accelerometer output noise, To reduce noise output from the gyroscope. For receiver clock error driving noise, and This is for zero-bias drive noise of the accelerometer and gyroscope. The measurement equation is:

[0041] in For satellite The line-of-sight vector between the carrier and the target.

[0042] The navigation error state variables are updated, and the estimated navigation error parameters are fed back to the INS system to correct the navigation parameters.

[0043] Step Six: Since the carrier frequency change is caused by satellite motion and carrier motion, the carrier motion state is recalculated using the corrected navigation parameter state variables to estimate the carrier frequency change rate. ,in Let be the relative acceleration between the carrier and the satellite, where is the acceleration between the carrier and the satellite. and Represents the acceleration vectors of the satellite and the receiver. and This represents the velocity vector between the satellite and the receiver. and This represents the position vectors of the satellite and the receiver. This indicates the distance between the satellite and the receiver. The code phase correction value is also obtained. With carrier frequency correction Tracking parameters are used to control the pseudocode and carrier NCO to maintain tracking of the input signal. and This indicates the calculated values ​​of pseudorange and pseudorange rate obtained using the position and velocity of the satellite and the carrier. For the carrier digitally controlled oscillator frequency, This represents the intermediate frequency of the signal. The above steps are executed cyclically.

[0044] The BeiDou dual-frequency INS vector depth integrated navigation system provided by the present invention is described below. The BeiDou dual-frequency INS vector depth integrated navigation system described below can be referred to in correspondence with the BeiDou dual-frequency INS vector depth integrated navigation method described above.

[0045] Figure 4 This is a schematic diagram of the structure of the BeiDou dual-frequency INS vector depth integrated navigation system provided in an embodiment of the present invention, as shown below. Figure 4 As shown, it includes: a first calculation module 41, a second calculation module 42, a third calculation module 43, a fourth calculation module 44, a fifth calculation module 45, and a sixth calculation module 46, wherein: The first calculation module 41 correlates the B1I and B3I satellite signals with the local signals generated by the carrier NCO and code NCO to obtain the discrimination error. The second calculation module 42 calculates the pseudorange and pseudorange rate using the satellite signal propagation time and Doppler frequency shift. The third calculation module 43 subtracts the pseudorange and pseudorange rate from the pseudorange error and pseudorange rate error calculated using the discrimination error to obtain the pseudorange measurement value and pseudorange rate measurement value, respectively. The fourth calculation module 44 solves the inertial navigation data to obtain the position and velocity of the carrier, analyzes the ephemeris to calculate the position and velocity of each satellite, and uses the position and velocity of the satellites and the carrier to obtain the pseudorange measurement value. The fifth calculation module 45 is used to subtract the pseudorange calculation value and pseudorange rate calculation value from the pseudorange measurement value and pseudorange rate measurement value, respectively, to obtain the pseudorange error measurement value and pseudorange rate error measurement value. The pseudorange error measurement value and pseudorange rate error measurement value are input into the combined navigation filter to update the navigation error state variable, and the navigation error parameters are fed back to the INS system to correct the navigation parameters. The sixth calculation module 46 is used to estimate the carrier frequency change rate and code phase and carrier frequency correction amount using the corrected navigation parameters and ephemeris information to control the pseudocode and carrier NCO, maintain tracking of the input signal, and repeat the above steps.

[0046] Figure 5 An example is a schematic diagram of the physical structure of an electronic device, such as... Figure 5As shown, the electronic device may include: a processor 510, a communication interface 520, a memory 530, and a communication bus 540. The processor 510, communication interface 520, and memory 530 communicate with each other via the communication bus 540. The processor 510 can call logical instructions in the memory 530 to execute the BeiDou dual-frequency INS vector-depth integrated navigation method. This method includes: correlating B1I and B3I satellite signals with local signals generated by carrier NCO and code NCO to obtain discrimination error; calculating pseudorange and pseudorange rate using satellite signal propagation time and Doppler frequency shift; subtracting the pseudorange and pseudorange rate from the pseudorange error and pseudorange rate error calculated using the discrimination error to obtain pseudorange measurement value and pseudorange rate measurement value, respectively; processing inertial navigation data to obtain the position and velocity of the carrier; analyzing ephemeris to calculate the position and velocity of each satellite; and using satellite... The positions and velocities of the satellite and the carrier are used to obtain pseudorange and pseudorange rate calculations. These values ​​are then subtracted from the pseudorange and pseudorange rate measurements to obtain pseudorange error and pseudorange rate error measurements, respectively. These values ​​are input into the integrated navigation filter to update the navigation error state variables, and the navigation error parameters are fed back to the INS system for correction. The corrected navigation parameters and ephemeris information are used to estimate the carrier frequency change rate and the code phase and carrier frequency correction amount to control the pseudocode and carrier NCO, maintaining tracking of the input signal. The above steps are then repeated.

[0047] Furthermore, the logical instructions in the aforementioned memory 530 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0048] On the other hand, the present invention also provides a non-transitory computer-readable storage medium storing a computer program thereon. When executed by a processor, the computer program implements the BeiDou dual-frequency INS vector-depth integrated navigation method provided by the above methods. This method includes: correlating B1I satellite signals and B3I satellite signals with local signals generated by carrier NCO and code NCO to obtain a discrimination error; calculating pseudorange and pseudorange rate using satellite signal propagation time and Doppler frequency shift; subtracting the pseudorange and pseudorange rate from the pseudorange error and pseudorange rate error calculated using the discrimination error, respectively, to obtain pseudorange measurement values ​​and pseudorange rate measurement values; and processing inertial navigation data to obtain the position and velocity of the carrier, and analyzing the satellite data. The positions and velocities of each satellite are calculated. Using the positions and velocities of the satellites and the carrier, pseudorange and pseudorange rate values ​​are obtained. These values ​​are then subtracted from the measured pseudorange and pseudorange rate values ​​to obtain the measured pseudorange error and pseudorange rate error values. These values ​​are input into the integrated navigation filter to update the navigation error state variables. The navigation error parameters are then fed back to the INS system for correction. Using the corrected navigation parameters and ephemeris information, the carrier frequency change rate and code phase and carrier frequency correction are estimated to control the pseudocode and carrier NCO, maintaining tracking of the input signal. The above steps are then repeated.

[0049] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0050] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0051] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A BeiDou dual-frequency INS vector depth integrated navigation method, characterized in that, include: The B1I and B3I satellite signals are correlated with the local signals generated by the carrier NCO and code NCO to obtain the discrimination error. Calculate pseudorange and pseudorange rate using satellite signal propagation time and Doppler frequency shift; Subtract the pseudorange and pseudorange rate from the pseudorange error and pseudorange rate error calculated using the discrimination error, respectively, to obtain the pseudorange measurement value and pseudorange rate measurement value; The position and velocity of the carrier are obtained by solving the inertial navigation data, the position and velocity of each satellite are obtained by analyzing the ephemeris, and the pseudorange and pseudorange rate are obtained by using the position and velocity of the satellites and the carrier. The pseudorange calculation value and pseudorange rate calculation value are subtracted from the pseudorange measurement value and pseudorange rate measurement value, respectively, to obtain the pseudorange error measurement value and pseudorange rate error measurement value. The pseudorange error measurement value and pseudorange rate error measurement value are input into the integrated navigation filter to update the navigation error state variable, and the navigation error parameters are fed back to the INS system to correct the navigation parameters. The carrier frequency change rate and code phase and carrier frequency correction amount are estimated using the corrected navigation parameters and ephemeris information to control the pseudocode and carrier NCO, maintain tracking of the input signal, and repeat the above steps. The B1I and B3I satellite signals are correlated with the local signals generated by the carrier NCO and code NCO to obtain the discrimination error, which includes: B1I satellite signals and B3I satellite signals are : Local signals generated by carrier NCO and code NCO : The correlation value is the sum of the products of the received signal and the locally replicated signal within the integration interval. : Obtain the error of the code detector error of carrier frequency discriminator ; in, The interval between early and late chips, For signal power, For modulated data, This is pseudocode. The sampling interval is... For data indexing, For carrier frequency offset, For noise terms, This refers to the code phase offset time. For carrier phase offset, This is the cumulative number of sampling points. and These are the in-phase and quadrature components of the advance code correlation value, respectively. and These are the in-phase and quadrature components of the correlation value of the hysteresis code, respectively. For cross power, The power is the dot product. The pseudorange and pseudorange rate are calculated using satellite signal propagation time and Doppler frequency shift, including: Calculate the satellite signal propagation time based on the received signal code phase, and calculate the code pseudorange. ; The ionospheric delay effect is corrected using a dual-frequency B1I / B3I de-ionization pseudorange formula. The Doppler frequency shift is obtained by subtracting the intermediate frequency signal frequency from the carrier frequency, and the pseudorange rate is calculated. ; in, It is the pseudorange corrected for ionosphere. and These are the observed pseudoranges of the B1I and B3I signals. It is the on-board equipment delay difference of the B1I signal. It's the speed of light. This represents the ionospheric delay scaling factor between the B1I and B3I frequency points. ,in For frequency variables.

2. The BeiDou dual-frequency INS vector depth integrated navigation method according to claim 1, characterized in that, Subtracting the pseudorange and pseudorange rate from the pseudorange error and pseudorange rate error calculated using the discrimination error, respectively, yields the pseudorange measurement value and pseudorange rate measurement value, including: in, Indicates the pseudorange measurement value. This represents the pseudorange rate measurement value. For pseudocode wavelength, Indicates the carrier wavelength. and These represent the code phase error and carrier frequency error within the measurement period, respectively.

3. The BeiDou dual-frequency INS vector depth integrated navigation method according to claim 1, characterized in that, The position and velocity of the carrier are obtained by solving the inertial navigation data; the position and velocity of each satellite are obtained by analyzing the ephemeris; and pseudorange and pseudorange rate values ​​are obtained using the positions and velocities of the satellites and the carrier, including: The position and velocity of the carrier are obtained by solving the inertial navigation data using a strapdown inertial navigation algorithm; The navigation message is analyzed to obtain ephemeris parameters, and the position and velocity of each tracked satellite are calculated using the ephemeris parameters. The pseudorange is calculated using the position and velocity of the satellite and the carrier. and pseudorange rate calculation value .

4. The BeiDou dual-frequency INS vector depth integrated navigation method according to claim 1, characterized in that, The pseudorange calculation value and pseudorange rate calculation value are subtracted from the pseudorange measurement value and pseudorange rate measurement value, respectively, to obtain the pseudorange error measurement value and pseudorange rate error measurement value. These values ​​are then input into the integrated navigation filter to update the navigation error state variable. The navigation error parameters are then fed back to the INS system for correction, including: pseudorange calculation value and pseudorange rate calculation value , respectively with pseudorange measurement values and pseudorange rate measurement The pseudorange error measurement and pseudorange rate error measurement obtained by subtraction are input into the integrated navigation filter, and the vector depth combined state variable is selected as the location under the geographic system. and speed error Attitude misalignment angle Clock error Three-axis gyroscope Zero bias of accelerometer ,Right now The system's state equation is the inertial navigation error propagation equation. ; in: The antisymmetric matrix representing the relative forces in the geographic coordinate system. This represents the direction cosine matrix from the body coordinate system to the geographic coordinate system. For accelerometer output noise, To reduce noise output from the gyroscope. For receiver clock error driving noise, and Zero-bias drive noise for accelerometers and gyroscopes; The measurement equation is: For satellite The line-of-sight vector between the carrier and the target. The navigation error state variables are updated, and the estimated navigation error parameters are fed back to the INS system to correct the navigation parameters.

5. The BeiDou dual-frequency INS vector depth integrated navigation method according to claim 1, characterized in that, The carrier frequency change rate and code phase and carrier frequency correction are estimated using the corrected navigation parameters and ephemeris information to control the pseudocode and carrier NCO, maintaining tracking of the input signal, including: The vehicle motion state is recalculated using the corrected navigation parameter state variables, and the carrier frequency change rate is estimated. ,in Let be the relative acceleration between the carrier and the satellite, where is the acceleration between the carrier and the satellite. and These represent the acceleration vectors of the satellite and the receiver, respectively. and These represent the velocity vectors of the satellite and the receiver, respectively. and These represent the position vectors of the satellite and the receiver, respectively. Indicates the distance between the satellite and the receiver; Obtain code phase correction amount With carrier frequency correction To control the pseudocode and carrier NCO, and maintain tracking of the input signal. For the carrier digitally controlled oscillator frequency, This indicates the intermediate frequency of the signal.

6. A BeiDou dual-frequency INS vector depth integrated navigation system, based on the BeiDou dual-frequency INS vector depth integrated navigation method according to any one of claims 1 to 5, characterized in that, include: The first calculation module is used to correlate the B1I satellite signal and the B3I satellite signal with the local signal generated by the carrier NCO and the code NCO to obtain the discrimination error; The second calculation module is used to calculate pseudorange and pseudorange rate using satellite signal propagation time and Doppler frequency shift; The third calculation module is used to subtract the pseudorange and pseudorange rate from the pseudorange error and pseudorange rate error calculated using the discrimination error, respectively, to obtain the pseudorange measurement value and pseudorange rate measurement value. The fourth calculation module is used to solve the inertial navigation data to obtain the position and velocity of the carrier, analyze the ephemeris to calculate the position and velocity of each satellite, and use the position and velocity of the satellites and the carrier to obtain the pseudorange calculation value and pseudorange rate calculation value. The fifth calculation module is used to subtract the pseudorange calculation value and pseudorange rate calculation value from the pseudorange measurement value and pseudorange rate measurement value, respectively, to obtain the pseudorange error measurement value and pseudorange rate error measurement value. The pseudorange error measurement value and pseudorange rate error measurement value are then input into the integrated navigation filter to update the navigation error state variable, and the navigation error parameters are fed back to the INS system to correct the navigation parameters. The sixth calculation module is used to estimate the carrier frequency change rate and code phase and carrier frequency correction amount using the corrected navigation parameters and ephemeris information, so as to control the pseudo code and carrier NCO, maintain tracking of the input signal, and repeat the above steps.

7. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the BeiDou dual-frequency INS vector depth combined navigation method as described in any one of claims 1 to 5.

8. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the BeiDou dual-frequency INS vector depth combined navigation method as described in any one of claims 1 to 5.

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