Beidou double-frequency INS vector deep integrated navigation method and system

Abstract

The invention provides a Beidou dual-frequency INS vector deep integrated navigation method and system. The method comprises the following steps: calculating and measuring a pseudo range and a pseudo range rate by using a Beidou signal identification result output by a correlator and a Beidou tracking channel pseudo range rate corrected by a dual-frequency ionosphere; a pseudo-range error between a pseudo-range calculated by a predicted position and a measured pseudo-range and a pseudo-range rate error between a pseudo-range rate calculated by a predicted speed and a measured pseudo-range rate are used as quantity measurement to be input into a combined navigation filter, and state variables are updated and fed back to an INS system to correct navigation parameters; according to the corrected navigation information and ephemeris information, code phase and carrier frequency correction for Beidou signal tracking are calculated to drive a code and carrier numerical control oscillator, and during the navigation updating interval, the code and carrier numerical control oscillator is updated by using the carrier frequency change rate calculated by the navigation result of the INS system.

Description

Technical Field

[0001] The present invention relates to the technical field of Beidou navigation, and particularly to a Beidou dual-frequency INS vector deep integration navigation method and system. Background Art

[0002] In an open scene with good observation conditions, the receiver can continuously receive satellite signals. However, in situations such as tree-lined roads, high-rise canyons, viaducts, tunnels, etc., where there is occlusion or high dynamicity of the carrier, the satellite receiver tracking loop is prone to losing lock or being unable to receive satellite signals normally, resulting in the continuity and availability of positioning not being guaranteed. And the use of INS-aided vector deep integration technology can significantly improve tracking accuracy, sensitivity, and continuity.

[0003] Currently, most of the proposed vector deep integration navigation technologies use signals such as GPS based on a single frequency point or Beidou B1C, etc., in combination with INS. Due to the single observation data, this combination form cannot eliminate the ionospheric error by solving simultaneous equations, and the used frequency points are common frequency points shared by multiple GNSS systems, which are easily interfered with and spoofed. However, B1I and B3I are unique frequency points of Beidou, which do not overlap with other navigation systems and naturally have anti-interference advantages, playing an important role in the applications of national defense and key national infrastructure. Therefore, the present invention proposes a Beidou dual-frequency INS vector deep integration 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, and at the same time has high integrated navigation accuracy and certain anti-interference ability. Summary of the Invention

[0004] The present invention provides a Beidou dual-frequency INS vector deep integration navigation method and system to solve the defects existing in the prior art.

[0005] In a first aspect, the present invention provides a Beidou dual-frequency INS vector deep integration navigation method, including: Correlating 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; Calculating the pseudorange and the pseudorange rate using the satellite signal propagation time and the Doppler frequency shift; Subtracting the pseudorange and the pseudorange rate from the pseudorange error and the pseudorange rate error calculated using the discrimination error respectively to obtain the pseudorange measurement value and the pseudorange rate measurement value; Solving the inertial navigation data to obtain the position and velocity of the carrier, parsing the ephemeris to calculate the position and velocity of each satellite, and using the position and velocity of the satellite and the carrier to obtain the calculated pseudorange value and the calculated pseudorange rate value; Subtract the calculated pseudorange value and the calculated pseudorange rate value from the measured pseudorange value and the measured pseudorange rate value respectively to obtain the measured pseudorange error value and the measured pseudorange rate error value. Input the measured pseudorange error value and the measured pseudorange rate error value into the integrated navigation filter to update the navigation error state variables, and feedback the navigation error parameters to the INS system to correct the navigation parameters; Estimate the carrier frequency change rate and the code phase and carrier frequency correction amounts by using the corrected navigation parameters and ephemeris information to control the pseudocode and carrier NCOs and maintain the tracking of the input signal. Repeat the above steps.

[0006] According to a Beidou dual-frequency INS vector deep integration navigation method provided by the present invention, correlate the B1I satellite signal and the B3I satellite signal with the local signals generated by the carrier NCO and the code NCO to obtain discrimination errors, including: The B1I satellite signal and the B3I satellite signal are :

[0007] The local signals generated by the carrier NCO and the code NCO :

[0008] The correlation value is the cumulative sum of the products of the received signal and the local replica signal within the integration interval :

[0009] Obtain the code phase discriminator error , and the carrier frequency discriminator error ; Among them, is the early-late chip interval, is the signal power, is the modulation data, is the pseudocode, is the sampling interval, is the data index, is the carrier frequency offset, is the noise term, is the code phase offset time, is the carrier phase offset, is the cumulative number of sampling points, and are the in-phase component and the quadrature component of the early code correlation value respectively, and are the in-phase component and the quadrature component of the late code correlation value respectively, is the cross power, is the dot product power.

[0010] According to a Beidou dual-frequency INS vector deep integration navigation method provided by the present invention, the pseudorange and pseudorange rate are calculated using the satellite signal propagation time and Doppler frequency shift, including: Calculating the satellite signal propagation time based on the received signal code phase, and calculating the code pseudorange ; Adopting a dual-frequency B1I / B3I ionosphere-free combined pseudorange formula to correct the ionosphere delay effect, obtaining the Doppler frequency shift by subtracting the intermediate frequency signal frequency from the carrier frequency, and calculating the pseudorange rate ;

[0011] Among them, is the pseudorange after ionosphere correction, and are the observed pseudoranges of B1I and B3I signals, is the on-board equipment time delay difference of B1I signal, is the speed of light, represents the ionosphere delay proportionality factor between B1I and B3I frequency points, , where is the frequency variable.

[0012] According to a Beidou dual-frequency INS vector deep integration navigation method provided by the present invention, subtracting 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] Among them, represents the pseudorange measurement value, represents the pseudorange rate measurement value, is the pseudocode wavelength, represents the carrier wavelength, and respectively represent the code phase error and carrier frequency error within the measurement period.

[0015] According to a Beidou dual-frequency INS vector deep integration navigation method provided by the present invention, resolving the inertial navigation data to obtain the position and velocity of the carrier, parsing the ephemeris to calculate the position and velocity of each satellite, and obtaining the pseudorange calculation value and pseudorange rate calculation value using the position and velocity of the satellite and the carrier, including: Adopting a strapdown inertial navigation algorithm to resolve the inertial navigation data to obtain the position and velocity of the carrier; Parsing the navigation message to obtain ephemeris parameters, and using the ephemeris parameters to calculate the position and velocity of the satellites that have been tracked; The calculated pseudorange value is obtained using the positions and velocities of the satellite and the vehicle and the calculated pseudorange rate value .

[0016] According to a Beidou dual-frequency INS vector deep integration navigation method provided by the present invention, the calculated pseudorange value and the calculated pseudorange rate value are respectively subtracted from the measured pseudorange value and the measured pseudorange rate value to obtain the measured pseudorange error value and the measured pseudorange rate error value. The measured pseudorange error value and the measured pseudorange rate error value are input into a combined navigation filter to update the navigation error state variables, and the navigation error parameters are fed back to the INS system to correct the navigation parameters, including: The calculated pseudorange value and the calculated pseudorange rate value , which are respectively subtracted from the measured pseudorange value and the measured pseudorange rate value to obtain the measured pseudorange error value and the measured pseudorange rate error value, which are input into a combined navigation filter. The vector deep integration state variables are selected as the position and velocity error in the geographic coordinate system, the attitude misalignment angle , the clock error , the triaxial gyroscopes and the accelerometer zero biases , that is . The state equation of the system is the inertial navigation error propagation equation ; Wherein:

[0017] represents the skew-symmetric matrix of the specific force in the geographic coordinate system, represents the direction cosine matrix from the body coordinate system to the geographic coordinate system, is the accelerometer output noise, is the gyroscope output noise, is the receiver clock error driving noise, and are the accelerometer and gyroscope zero bias driving noises; The measurement equation is:

[0018] is the line-of-sight vector between the satellite and the vehicle; 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] A Beidou dual-frequency INS vector deep integration navigation method provided by the present invention estimates the carrier frequency change rate and the code phase and carrier frequency correction amounts by using the calibrated navigation parameters and ephemeris information to control the pseudo-code and carrier NCOs and maintain the tracking of the input signal, including: Recalculating the carrier motion state by using the calibrated navigation parameter state variables and estimating the carrier frequency change rate , where is the relative acceleration between the carrier and the satellite, and in the formula and respectively represent the acceleration vectors of the satellite and the receiver, and respectively represent the velocity vectors of the satellite and the receiver, and respectively represent the position vectors of the satellite and the receiver, represents the distance between the satellite and the receiver; Obtaining the code phase correction amount and the carrier frequency correction amount to control the pseudo-code and carrier NCOs and maintain the tracking of the input signal, is the frequency of the carrier numerically controlled oscillator, represents the intermediate frequency of the signal.

[0020] In a second aspect, the present invention also provides a Beidou dual-frequency INS vector deep integration navigation system, including: A first calculation module for correlating the B1I satellite signal and the B3I satellite signal with the local signals generated by the carrier NCO and the code NCO to obtain the discrimination error; A second calculation module for calculating the pseudorange and the pseudorange rate by using the satellite signal propagation time and the Doppler frequency shift; A third calculation module for subtracting the pseudorange and the pseudorange rate from the pseudorange error and the pseudorange rate error calculated by using the discrimination error respectively to obtain the pseudorange measurement value and the pseudorange rate measurement value; A fourth calculation module for resolving the inertial navigation data to obtain the position and velocity of the carrier, calculating the positions and velocities of each satellite by parsing the ephemeris, and obtaining the pseudorange calculation value and the pseudorange rate calculation value by using the positions and velocities of the satellite and the carrier; A fifth calculation module for subtracting the pseudorange calculation value and the pseudorange rate calculation value from the pseudorange measurement value and the pseudorange rate measurement value respectively to obtain the pseudorange error measurement value and the pseudorange rate error measurement value, inputting the pseudorange error measurement value and the pseudorange rate error measurement value into the integrated navigation filter to update the navigation error state variables, and feeding back the navigation error parameters to the INS system to correct the navigation parameters; The sixth calculation module is used to estimate the carrier frequency change rate and the code phase and carrier frequency correction amount by using the corrected navigation parameters and ephemeris information, so as to control the pseudo-code and carrier NCO, maintain the tracking of the input signal, and repeatedly execute the above steps.

[0021] In a third aspect, the present invention further provides an electronic device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the program, it implements the Beidou dual-frequency INS vector deep integration navigation method as described in any one of the above.

[0022] In a fourth aspect, the present invention further provides a non-transitory computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, it implements the Beidou dual-frequency INS vector deep integration navigation method as described in any one of the above.

[0023] The Beidou dual-frequency INS vector deep integration navigation method and system provided by the present invention have the following advantages: (1) Focus on the frequency point combination within the Beidou system, fully exploit the potential of the Beidou system itself, and fuse IMU data into the tracking loops of Beidou B1I and B3I signals; (2) Adopt the method of vector tracking, which can use the information of strong signal channels to assist the tracking of weak signal channels, and can continuously track more visible satellites in complex environments; (3) Utilize IMU-assisted carrier frequency prediction, and the loop is not easy to lose lock in the case of high dynamic of the carrier. Even if the signal is lost in a short-term full occlusion scenario, it can quickly complete acquisition and positioning calculation after the signal appears. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0025] Figure 1 is a schematic flow chart of the Beidou dual-frequency INS vector deep integration navigation method provided by the present invention; Figure 2 is a Beidou dual-frequency INS vector deep integration structure diagram provided by the present invention; Figure 3 is a Beidou dual-frequency INS vector deep integration implementation block diagram provided by the present invention; Figure 4 is a schematic structural diagram of the Beidou dual-frequency INS vector deep integration navigation system provided by the present invention; Figure 5It is a schematic structural diagram of the electronic device provided by the present invention. Specific Embodiments

[0026] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions in the present invention will be clearly and completely described below with reference to the accompanying drawings in the present invention. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention without creative efforts shall fall within the protection scope of the present invention.

[0027] Figure 1 It is a schematic flowchart of the Beidou dual-frequency INS vector deep integration navigation method provided by an embodiment of the present invention. As Figure 1 shown, it includes: Step 100: Correlate the B1I satellite signal and the B3I satellite signal with the local signals generated by the carrier NCO and the code NCO to obtain discrimination errors; Step 200: Calculate the pseudorange and pseudorange rate using the 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 errors respectively to obtain the pseudorange measurement value and the pseudorange rate measurement value; Step 400: Solve the inertial navigation data to obtain the position and velocity of the carrier, analyze the ephemeris to calculate the positions and velocities of each satellite, and use the positions and velocities of the satellite and the carrier to obtain the calculated pseudorange value and the calculated pseudorange rate value; Step 500: Subtract the calculated pseudorange value and the calculated pseudorange rate value from the pseudorange measurement value and the pseudorange rate measurement value respectively to obtain the pseudorange error measurement value and the pseudorange rate error measurement value. Input the pseudorange error measurement value and the pseudorange rate error measurement value into the integrated navigation filter to update the navigation error state variables, and feedback the navigation error parameters to the INS system to correct the navigation parameters; Step 600: Estimate the carrier frequency change rate and the code phase and carrier frequency correction amount using the corrected navigation parameters and ephemeris information to control the pseudocode and the carrier NCO, maintain the tracking of the input signal, and repeat the above steps.

[0028] Specifically, as Figure 2As shown in the figure, in the embodiment of the present invention, the Beidou signal discrimination result output by the correlator and the pseudorange rate of the Beidou tracking channel after dual-frequency ionospheric correction are used to calculate the measured pseudorange and pseudorange rate; the pseudorange error between the pseudorange calculated using the predicted position and the measured pseudorange, and the pseudorange rate error between the pseudorange rate calculated using the predicted speed and the measured pseudorange rate are used as measurement inputs to the integrated navigation filter to update the state variables and feedback to the INS system to correct the navigation parameters; according to the corrected navigation information and ephemeris information, the code phase and carrier frequency correction amounts for Beidou signal tracking are calculated to drive the code and carrier numerically controlled oscillators, where during the navigation update interval, the code and carrier numerically controlled oscillators are updated using the carrier frequency change rate calculated from the navigation results of the INS system.

[0029] By considering the combined vector loop tracking method of single Beidou dual-frequency signal and strapdown inertial navigation INS, the deep combination positioning method, and the dual-frequency ionospheric error elimination method for Beidou receiver navigation, the present invention can improve the loop continuous tracking performance, fast reacquisition performance, and high-precision positioning performance of Beidou B1I and B3I signals in complex environments and high-dynamic situations, and at the same time has a certain anti-interference ability.

[0030] Based on the above embodiment, as Figure 3 shown, the specific implementation steps of the embodiment of the present invention include: Step 1: The received model of the Beidou B1I or B3I signal collected by the RF front end is: , and the locally generated signal model is: , and the correlation value is the sum of the products of the received signal and the local replica signal integrated within: . The code phase discriminator error and the carrier frequency discriminator error are obtained.

[0031] Among them, is the early-late chip interval, is the signal power, is the modulation data, is the pseudocode, is the sampling interval, is the data index, is the carrier frequency offset, is the noise term, is the code phase offset time, is the carrier phase offset, is the cumulative number of sampling points, and are the in-phase and quadrature components of the early code correlation value respectively, and are the in-phase and quadrature components of the late code correlation value respectively, is the cross power, is the dot product power.

[0032] Step 2: Calculate the satellite signal propagation time according to the received signal code phase, and calculate the code pseudorange accordingly . The dual-frequency B1I / B3I ionosphere-free combined 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 . is the pseudorange after ionospheric correction; and are the observed pseudoranges of B1I and B3I signals (corrected for satellite clock error but not corrected); is the on-board equipment time delay difference of the B1I signal; where is the speed of light.

[0033]

[0034] represents the ionospheric delay scale factor between the B1I and B3I frequency points, , where is the frequency variable.

[0035] Step 3: During a pseudorange and pseudorange rate measurement period, there are output values from the code phase discriminator and the carrier frequency discriminator. Remove the code phase error and the carrier frequency error to reduce the measurement noise. That is, the pseudorange measurement value is: , where is the pseudocode wavelength. The pseudorange rate measurement value is: . represents the carrier wavelength, and represent the code phase error and the carrier frequency error during 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 carrier; analyze the navigation message to obtain the ephemeris parameters, and use the ephemeris parameters to calculate the positions and velocities of the tracked satellites; use the positions and velocities of the satellites and the carrier to obtain the calculated values of the pseudorange and the pseudorange rate and .

[0037] Step 5: Subtract the calculated values of the pseudorange and the pseudorange rate and from the pseudorange rate measurement values and to obtain the pseudorange and pseudorange rate error measurement values and input them into the navigation filter. The vector deep combination state variables are selected as the position and velocity errors in the geographical coordinate system, the attitude misalignment angle, the clock error, and the zero biases of the three-axis gyroscopes and accelerometers, that is , the state equation of the system is the inertial navigation error propagation equation: .

[0038] Where:

[0039] represents the skew-symmetric matrix of the specific force in the geodetic coordinate system, represents the direction cosine matrix from the body coordinate system to the geodetic coordinate system.

[0040] In the formula, is the accelerometer output noise, is the gyroscope output noise, is the receiver clock error driving noise, and are the accelerometer and gyroscope bias driving noises. The measurement equation is:

[0041] Where is the satellite and the line-of-sight vector between the carrier and the satellite.

[0042] Update the navigation error state variables, and feedback the estimated navigation error parameters back to the INS system to correct the navigation parameters.

[0043] Step 6: 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, thereby estimating the carrier frequency change rate , where is the relative acceleration between the carrier and the satellite. In the formula and represent the acceleration vectors of the satellite and the receiver, and represent the velocity vectors of the satellite and the receiver, and represent the position vectors of the satellite and the receiver, represents the distance between the satellite and the receiver. At the same time, the code phase correction amount and the carrier frequency correction amount and other tracking parameters are obtained to control the pseudo-code and carrier NCO to maintain tracking of the input signal. and represent the calculated values of the pseudo-range and pseudo-range rate obtained using the positions and velocities of the satellite and the carrier. is the carrier numerically controlled oscillator frequency, represents the intermediate frequency of the signal. The above steps are executed in a loop.

[0044] The Beidou dual-frequency INS vector deep integration navigation system provided by the present invention will be described below. The Beidou dual-frequency INS vector deep integration navigation system described below can be correspondingly referred to the Beidou dual-frequency INS vector deep integration navigation method described above.

[0045] Figure 4 is a schematic structural diagram of the Beidou dual-frequency INS vector deep integration navigation system provided by an embodiment of the present invention, as Figure 4 shown, including: 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, where: The first calculation module 41 is used to correlate the B1I satellite signal and the B3I satellite signal with the local signals generated by the carrier NCO and the code NCO to obtain discrimination errors; the second calculation module 42 is used to calculate the pseudorange and pseudorange rate using the satellite signal propagation time and Doppler frequency shift; the third calculation module 43 is used to subtract the pseudorange and pseudorange rate from the pseudorange error and pseudorange rate error calculated using the discrimination errors respectively to obtain the pseudorange measurement value and the pseudorange rate measurement value; the fourth calculation module 44 is used to solve the inertial navigation data to obtain the position and velocity of the carrier, calculate the positions and velocities of each satellite by parsing the ephemeris, and obtain the pseudorange calculation value and the pseudorange rate calculation value using the positions and velocities of the satellite and the carrier; the fifth calculation module 45 is used to subtract the pseudorange calculation value and the pseudorange rate calculation value from the pseudorange measurement value and the pseudorange rate measurement value respectively to obtain the pseudorange error measurement value and the pseudorange rate error measurement value, input the pseudorange error measurement value and the pseudorange rate error measurement value into the integrated navigation filter to update the navigation error state variables, and feedback the navigation error parameters to the INS system to correct the navigation parameters; the sixth calculation module 46 is used to estimate the carrier frequency change rate and the code phase and carrier frequency correction amounts using the corrected navigation parameters and ephemeris information to control the pseudocode and the carrier NCO to maintain tracking of the input signal, and repeat the above steps.

[0046] Figure 5 illustrates a schematic structural diagram of an electronic device, as Figure 5As shown in the figure, the electronic device may include: a processor 510, a communications interface 520, a memory 530, and a communication bus 540. Among them, the processor 510, the communications interface 520, and the memory 530 complete communication with each other through the communication bus 540. The processor 510 can call the logical instructions in the memory 530 to execute the Beidou dual-frequency INS vector deep integration navigation method. The method includes: correlating the B1I satellite signal and the B3I satellite signal with the local signals generated by the carrier NCO and the code NCO to obtain the discrimination error; calculating the pseudorange and the pseudorange rate using the satellite signal propagation time and the Doppler frequency shift; subtracting the pseudorange and the pseudorange rate from the pseudorange error and the pseudorange rate error calculated using the discrimination error respectively to obtain the pseudorange measurement value and the pseudorange rate measurement value; resolving the inertial navigation data to obtain the position and velocity of the carrier, parsing the ephemeris to calculate the positions and velocities of each satellite, and using the positions and velocities of the satellite and the carrier to obtain the calculated pseudorange value and the calculated pseudorange rate value; subtracting the calculated pseudorange value and the calculated pseudorange rate value from the pseudorange measurement value and the pseudorange rate measurement value respectively to obtain the pseudorange error measurement value and the pseudorange rate error measurement value, inputting the pseudorange error measurement value and the pseudorange rate error measurement value into the integrated navigation filter to update the navigation error state variables, and feeding back the navigation error parameters to the INS system to correct the navigation parameters; estimating the carrier frequency change rate and the code phase and carrier frequency correction amount using the corrected navigation parameters and the ephemeris information to control the pseudocode and the carrier NCO, maintaining the tracking of the input signal, and repeating the above steps.

[0047] In addition, when the logical instructions in the above-mentioned memory 530 are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of this 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 for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The foregoing storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks, or optical discs that can store program codes.

[0048] On the other hand, the present invention also provides a non-transitory computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, it implements the Beidou dual-frequency INS vector deep integration navigation method provided by the above-mentioned various methods. The method includes: correlating the B1I satellite signal and the B3I satellite signal with the local signals generated by the carrier NCO and the code NCO to obtain discrimination errors; calculating the pseudorange and pseudorange rate using the 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 errors respectively to obtain the pseudorange measurement value and the pseudorange rate measurement value; resolving the inertial navigation data to obtain the position and velocity of the carrier, calculating the positions and velocities of each satellite by parsing the ephemeris, and obtaining the pseudorange calculation value and the pseudorange rate calculation value using the positions and velocities of the satellite and the carrier; subtracting the pseudorange calculation value and the pseudorange rate calculation value from the pseudorange measurement value and the pseudorange rate measurement value respectively to obtain the pseudorange error measurement value and the pseudorange rate error measurement value, inputting the pseudorange error measurement value and the pseudorange rate error measurement value into the integrated navigation filter to update the navigation error state variables, and feeding back the navigation error parameters to the INS system to correct the navigation parameters; estimating the carrier frequency change rate and the code phase and carrier frequency correction amounts using the corrected navigation parameters and ephemeris information to control the pseudocode and carrier NCO, maintaining the tracking of the input signal, and repeating the above steps.

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

[0050] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a necessary general hardware platform, and of course, also by hardware. Based on such an understanding, the essence of the above technical solution or the part that contributes to the prior art can be embodied in the form of a software product. The computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., including several instructions for causing a computer device (which can be a personal computer, server, or network device, etc.) to execute the methods described in each embodiment 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 are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements 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 deep integration navigation method, characterized in that: include: The B1I satellite signal and the B3I satellite signal are correlated with the local signal generated by the carrier NCO and the code NCO to obtain the identification error; Calculate 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 identification error, respectively, to obtain a pseudorange measurement value and a pseudorange rate measurement value; The inertial navigation data is solved to obtain the position and velocity of the carrier, the ephemeris is analyzed to calculate the position and velocity of each satellite, and the position and velocity of the satellite and the carrier are used to obtain the pseudorange calculation value and pseudorange rate calculation value; Subtract the pseudorange calculated value and the pseudorange rate calculated value from the pseudorange measured value and the pseudorange rate measured value respectively to obtain the pseudorange error measured value and the pseudorange rate error measured value, input the pseudorange error measured value and the pseudorange rate error measured value into the combined navigation filter, update the navigation error state variable, and feed back the navigation error parameter to the INS system to correct the navigation parameter; The carrier frequency change rate and the code phase and carrier frequency correction are estimated using the corrected navigation parameters and ephemeris information to control the pseudo code and carrier NCO, keep tracking the input signal, and repeat the above steps.

2. The Beidou dual-frequency INS vector deep integrated navigation method according to claim 1, characterized in that: The B1I satellite signal and the B3I satellite signal are correlated with the local signal generated by the carrier NCO and the code NCO to obtain the identification error, including: The B1I satellite signal and the B3I satellite signal are : Local signal generated by carrier NCO and code NCO : The correlation value is the product and accumulation of the received signal and the local replica signal during the integration period. : Get the code phase detector error , and the carrier frequency discriminator error ; in, is the early and late chip interval, is the signal power, For modulation data, is pseudo code, is the sampling interval, is the data index, is the carrier frequency offset, is the noise term, is the code phase offset time, is the carrier phase offset, is the cumulative number of sampling points, and are the in-phase component and the orthogonal component of the advance code correlation value, and are the in-phase component and the orthogonal component of the delayed code correlation value, is the crossover power, is the dot product power.

3. The Beidou dual-frequency INS vector deep integrated navigation method according to claim 1, characterized in that: 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 dual-frequency B1I / B3I ionospheric elimination combined pseudorange formula is used to correct the ionospheric delay effect, and the Doppler frequency shift is obtained by subtracting the intermediate frequency signal frequency from the carrier frequency to calculate the pseudorange rate. ; in, is the pseudorange after ionospheric correction, and is the observed pseudorange of the B1I and B3I signals, is the onboard equipment delay difference of the B1I signal, is the speed of light, represents the ionospheric delay scaling factor between B1I and B3I frequency points, ,in is a frequency variable.

4. The Beidou dual-frequency INS vector deep integrated navigation method according to claim 1 is characterized in that: Subtract the pseudorange error and pseudorange rate error calculated using the identification error from the pseudorange and pseudorange rate to obtain the pseudorange measurement value and pseudorange rate measurement value, including: in, represents the pseudorange measurement value, represents the pseudorange rate measurement value, is the pseudo code wavelength, represents the carrier wavelength, and They represent the code phase error and carrier frequency error within the measurement period respectively.

5. The Beidou dual-frequency INS vector deep integrated navigation method according to claim 1 is characterized in that: The inertial navigation data is solved to obtain the position and velocity of the carrier, the ephemeris is analyzed to calculate the position and velocity of each satellite, and the position and velocity of the satellite and the carrier are used to obtain the pseudorange calculation value and pseudorange rate calculation value, including: The strapdown inertial navigation algorithm is used to solve the inertial navigation data to obtain the position and speed of the carrier; Parse the navigation message to obtain the ephemeris parameters, and use the ephemeris parameters to calculate the position and speed of each tracked satellite; The pseudo-range calculation value is obtained using the position and velocity of the satellite and the carrier and pseudorange rate calculation value .

6. The Beidou dual-frequency INS vector deep integrated navigation method according to claim 1, characterized in that: Subtract the pseudorange calculated value and the pseudorange rate calculated value from the pseudorange measured value and the pseudorange rate measured value respectively to obtain the pseudorange error measured value and the pseudorange rate error measured value, input the pseudorange error measured value and the pseudorange rate error measured value into the combined navigation filter, update the navigation error state variable, and feed back the navigation error parameter to the INS system to correct the navigation parameter, including: The pseudorange calculation value and pseudorange rate calculation value , respectively, with the pseudorange measurement value and pseudorange rate measurements The pseudorange error measurement value and pseudorange rate error measurement value obtained by subtraction are input into the integrated navigation filter, and the vector deep combined state variable is selected as the position in the geographic system and speed error 、Attitude misalignment angle , clock error , three-axis gyroscope Accelerometer bias ,Right now , the state equation of the system is the inertial error propagation equation ; in: The antisymmetric matrix representing the specific force in the geographic coordinate system, Represents the direction cosine matrix from the body coordinate system to the geographic coordinate system, is the accelerometer output noise, is the gyroscope output noise, is the 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 to the carrier; 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.

7. The Beidou dual-frequency INS vector deep 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 pseudo code and carrier NCO to keep tracking the input signal, including: Recalculate the carrier motion state using the corrected navigation parameter state and estimate the carrier frequency change rate ,in is the relative acceleration between the carrier and the satellite, where and denote the acceleration vectors of the satellite and receiver respectively, and represent the velocity vectors of the satellite and the receiver respectively, and represent the position vectors of the satellite and the receiver respectively, Indicates the distance between the satellite and the receiver; Get the code phase correction Carrier frequency correction , to control the pseudo code and carrier NCO, keep tracking the input signal, is the carrier digitally controlled oscillator frequency, Indicates the intermediate frequency of the signal.

8. A Beidou dual-frequency INS vector deep integrated navigation system, characterized in that: include: A 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 an identification error; The second calculation module is used to calculate the pseudorange and pseudorange rate by using the satellite signal propagation time and Doppler frequency shift; A third calculation module is used to subtract the pseudorange and pseudorange rate from the pseudorange error and pseudorange rate error calculated using the identification error, respectively, to obtain a pseudorange measurement value and a pseudorange rate measurement value; A 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 satellite and the carrier to obtain a pseudorange calculation value and a pseudorange rate calculation value; a fifth calculation module, for subtracting the pseudorange calculated value and the pseudorange rate calculated value from the pseudorange measured value and the pseudorange rate measured value, respectively, to obtain a pseudorange error measured value and a pseudorange rate error measured value, inputting the pseudorange error measured value and the pseudorange rate error measured value into a combined navigation filter, updating a navigation error state variable, and feeding back the navigation error parameter to the INS system to correct the navigation parameter; The sixth calculation module is used to estimate the carrier frequency change rate and the code phase and carrier frequency correction using the corrected navigation parameters and ephemeris information to control the pseudo code and carrier NCO, keep tracking the input signal, and repeat the above steps.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the program, the Beidou dual-frequency INS vector deep integration navigation method as described in any one of claims 1 to 7 is implemented.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the Beidou dual-frequency INS vector deep integrated navigation method as described in any one of claims 1 to 7 is implemented.

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