CN112394377B - Navigation method, device, electronic device and storage medium - Google Patents

Abstract

The embodiment of the present application discloses a navigation method, device, electronic device and storage medium. The method includes: obtaining the measured values of pseudorange and pseudorange rate of the global positioning system, obtaining the predicted values of pseudorange and pseudorange rate of the inertial navigation system at the same time as the global positioning system, calculating the measurement information of the combined positioning system of the global positioning system and the inertial navigation system according to the measured values of the pseudorange and pseudorange rate and the predicted values of the pseudorange and pseudorange rate, and eliminating the time synchronization error between the inertial navigation system and the global positioning system according to the measurement information to correct the positioning of the combined positioning system of the global positioning system and the inertial navigation system. By eliminating the time synchronization error between the global positioning system and the inertial navigation system, the accuracy of navigation is improved.

Description

Navigation method, device, electronic device and storage medium

Technical Field

The present application relates to the field of communication technology, and in particular to a navigation method, device, electronic device and storage medium.

Background technique

Integrated navigation refers to a navigation system that integrates various navigation devices and is controlled by monitors and computers. Most integrated navigation systems are based on inertial navigation systems (INS), mainly because inertial navigation can provide more navigation parameters and full attitude information parameters, which are unmatched by other navigation systems. At the same time, the global positioning system (GPS) is also needed as an auxiliary.

At present, the solution to the time synchronization error of GPS/INS integrated navigation at the software level is to estimate the existing time synchronization error as the state of the Kalman filter, and the loose combination of INS/GPS has certain limitations. For example, there is a problem of filter cascading in the loose combination, and the statistical observability of the INS error is relatively weak. What's more, when the GPS navigation solution alone cannot be obtained due to the insufficient number of visible satellites, the GPS/INS loose combination navigation fails. This has led to the GPS/INS tight combination navigation, but the existing GPS/INS tight combination navigation also has time synchronization errors, and the arithmetic calculation of the pseudorange, pseudorange rate and pseudorange rate derivative is relatively complicated for a single satellite single calculation, and it is slow to obtain an accurate navigation position.

Summary of the invention

The embodiments of the present application provide a navigation method, device, electronic device and storage medium, which can eliminate the time synchronization error in the GPS/INS tightly combined navigation system and improve the navigation accuracy and positioning speed.

In a first aspect, an embodiment of the present application provides a navigation method, the navigation method comprising:

Obtaining GPS pseudorange and pseudorange rate measurements;

Obtaining predicted values of pseudorange and pseudorange rate of an inertial navigation system at the same time as the global positioning system;

Calculating measurement information of the combined positioning system of the global positioning system and the inertial navigation system according to the measured values of the pseudorange and the pseudorange rate and the predicted values of the pseudorange and the pseudorange rate;

The time synchronization error between the inertial navigation system and the global positioning system is eliminated according to the measurement information to correct the positioning of the combined positioning system of the global positioning system and the inertial navigation system.

In a second aspect, an embodiment of the present application provides a navigation device, the navigation device comprising:

A first acquisition module is used to obtain the measured values of pseudorange and pseudorange rate of the global positioning system;

A second acquisition module is used to obtain the predicted values of the pseudorange and pseudorange rate of the inertial navigation system at the same time as the global positioning system;

A calculation module, used for calculating the measurement information of the combined positioning system of the global positioning system and the inertial navigation system according to the measured values of the pseudorange and the pseudorange rate and the predicted values of the pseudorange and the pseudorange rate;

The correction module is used to eliminate the time synchronization error between the inertial navigation system and the global positioning system according to the measurement information, so as to correct the positioning of the combined positioning system of the global positioning system and the inertial navigation system.

In a third aspect, an embodiment of the present application 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 implements the steps in the above-mentioned navigation method when executing the program.

In a fourth aspect, an embodiment of the present application provides a storage medium having a computer program stored thereon, wherein the computer program implements the steps in the above-mentioned navigation method when executed by a processor.

The embodiment of the present application obtains the measured values of pseudorange and pseudorange rate of the global positioning system, obtains the predicted values of pseudorange and pseudorange rate of the inertial navigation system at the same time as the global positioning system, calculates the measurement information of the combined positioning system of the global positioning system and the inertial navigation system according to the measured values of the pseudorange and pseudorange rate and the predicted values of the pseudorange and pseudorange rate, and eliminates the time synchronization error between the inertial navigation system and the global positioning system according to the measurement information to correct the positioning of the combined positioning system of the global positioning system and the inertial navigation system. By eliminating the time synchronization error between the global positioning system and the inertial navigation system, the accuracy of navigation is improved.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

FIG. 1 is a first flow chart of a navigation method provided in an embodiment of the present application.

FIG. 2 is a second flow chart of the navigation method provided in an embodiment of the present application.

FIG. 3 is a schematic diagram of a scenario of a navigation method provided in an embodiment of the present application.

FIG. 4 is an error comparison curve diagram provided in an embodiment of the present application.

FIG. 5 is a first structural diagram of a navigation device provided in an embodiment of the present application.

FIG. 6 is a second schematic diagram of the structure of the navigation device provided in an embodiment of the present application.

FIG. 7 is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application.

Detailed ways

The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of this application.

In the following description, the specific embodiments of the present application will be described with reference to the steps and symbols performed by one or more computers, unless otherwise stated. Therefore, these steps and operations will be mentioned several times as being performed by a computer, and the computer execution referred to herein includes the operation of a computer processing unit by an electronic signal representing data in a structured form. This operation converts the data or maintains it at a location in the memory system of the computer, which can be reconfigured or otherwise change the operation of the computer in a manner familiar to testers in the field. The data structure maintained by the data is a physical location in the memory, which has specific characteristics defined by the data format. However, the principles of the present application are described in the above text, which does not represent a limitation, and testers in the field will understand that the various steps and operations described below can also be implemented in hardware.

The terms "first", "second", and "third" in this application are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or device that includes a series of steps or modules is not limited to the listed steps or modules, but some embodiments also include steps or modules that are not listed, or some embodiments also include other steps or modules inherent to these processes, methods, products, or devices.

The embodiments of the present application provide a navigation method, device, electronic device and storage medium, which are described in detail below.

GPS (Global Positioning System) is the most widely used satellite navigation and positioning system. It is easy to use and low-cost. Its latest actual positioning accuracy has reached within 5 meters. However, the military application of GPS system still has some shortcomings, such as susceptibility to interference, poor reliability in dynamic environment and low data output frequency.

The method currently adopted is to combine the GPS navigation system and the INS navigation system (Inertial Navigation System) to form a GPS/INS integrated navigation system. Currently, the GPS/INS integrated navigation system includes a GPS/INS tight integrated navigation system and a GPS/INS loose integrated navigation system.

Among these two combined navigation systems, there is a time synchronization error between the GPS navigation system and the INS navigation system, which will lead to inaccurate positioning during the navigation process.

The navigation method in the embodiment of the present application eliminates the time synchronization error in the GPS/INS tightly integrated navigation system to improve the navigation accuracy and positioning speed of the GPS/INS tightly integrated navigation system. Please refer to Figure 1 for details, which is a first flow chart of the navigation method provided in the embodiment of the present application.

In step 101, the measured values of pseudorange and pseudorange rate of the global positioning system are obtained.

Pseudorange refers to the approximate distance between the ground receiver and the satellite during satellite positioning. Assuming that the satellite clock and the receiver clock are strictly synchronized, the propagation time of the signal can be obtained based on the transmission time of the satellite signal and the reception time of the signal by the receiver, and then multiplied by the propagation speed to get the satellite-to-earth distance. However, there is inevitably a clock error between the two clocks, and the signal is also affected by factors such as atmospheric refraction during propagation. Therefore, the distance directly measured by this method is not equal to the true distance from the satellite to the ground receiver, so this distance is called pseudorange.

Using the distance triangle measurement principle, the user's GPS receiver receives signals from four satellites at the same time, and can calculate the three-dimensional spatial position of the user's GPS receiver. At the same time, by performing time differentiation on the distance obtained during the measurement time, the user's GPS receiver can calculate the satellite's Doppler frequency based on the relationship between linear velocity and Doppler frequency, and thus calculate its own movement speed. Since the clock reference of the user's receiver has an error relative to the atomic clock reference of GPS, the actual measured distance is called "pseudo range", and the velocity measurement value obtained by differentiating the pseudo range within the actual measurement time interval is called "Delta pseudo range", also known as "pseudo range rate".

The measured values of pseudorange and pseudorange rate of the global positioning system can be obtained from the GPS ranging processor, wherein the pseudorange measurement value of the GPS navigation system can be obtained by a first preset algorithm, for example, the pseudorange measurement value in the GPS ranging processor is obtained by code tracking.

The pseudo-range rate measurement value of the GPS navigation system can be obtained by a second preset algorithm, for example, obtaining the pseudo-range rate measurement value in the GPS ranging processor from the carrier wave. It should be noted that the first preset algorithm and the second preset algorithm are not limited to the above algorithms.

In some embodiments, the pseudorange and pseudorange rate in the GPS navigation system may also be measured values actively output by the GPS ranging processor.

In step 102, the predicted values of the pseudorange and pseudorange rate of the inertial navigation system at the same time as the global positioning system are obtained.

In one embodiment, the predicted values of the pseudorange and pseudorange rate of the inertial navigation system at the same time as the global positioning system can be obtained based on the system parameters in the INS navigation system, wherein the system parameters may include the inertial navigation solution of the INS navigation system, the estimated clock error and clock drift, and satellite parameters, wherein the satellite parameters include the satellite position and velocity calculated by the message, etc.

In one embodiment, the inertial navigation solution of the INS navigation system may be transformed into a lever arm coordinate to obtain a first conversion value and a second conversion value, and the estimated values of the pseudorange and pseudorange rate of the INS navigation system may be calculated based on the first conversion value, the second conversion value and the unit line of sight distance vector of the satellite and the electronic device.

In step 103, measurement information of the combined positioning system of the global positioning system and the inertial navigation system is calculated according to the measured values of the pseudorange and the pseudorange rate and the predicted values of the pseudorange and the pseudorange rate.

It is understandable that due to the different sampling frequencies of the GPS navigation system and the INS navigation system and the time delay in the transmission of information to the combined filter, there is a time synchronization problem between the GPS pseudorange and pseudorange rate measurements and the estimated values of the pseudorange and pseudorange rate predicted by using parameters such as the INS navigation solution.

At this time, the measurement information can be obtained according to the measured values of the pseudorange and pseudorange rate of the GPS navigation system and the predicted values of the pseudorange and pseudorange rate of the INS navigation system. For example, the measurement information can be obtained by subtracting the measured value of the pseudorange of the GPS navigation system from the predicted value of the pseudorange of the INS navigation system, and by subtracting the measured value of the pseudorange rate of the GPS navigation system from the predicted value of the pseudorange rate of the INS navigation system.

In step 104, the time synchronization error between the inertial navigation system and the global positioning system is eliminated according to the measurement information to correct the positioning of the combined positioning system of the global positioning system and the inertial navigation system.

In one embodiment, after obtaining the measurement information, the time synchronization error between the INS navigation system and the GPS navigation system can be obtained based on the measurement information, and then the time synchronization error is eliminated, and the time synchronization error of the GPS/INS tightly combined navigation system is corrected, so that accurate positioning information can be obtained.

The measurement information that can be used includes some error parameters between the INS navigation system and the GPS navigation system. The error parameters include errors between the GPS navigation system and the INS navigation system, such as time synchronization errors, positioning position, speed and other errors.

Specifically, the measurement information can be used to calculate the measurement vector and the error state vector, and the measurement information can be used to update the error state vector to obtain the position, velocity and attitude error state solution at the target moment, as well as the zero bias of the IMU (Inertial measurement unit), and the clock deviation and drift of the electronic device.

Finally, these errors are eliminated to correct the time synchronization error of the GPS/INS tightly integrated navigation system. The correction method can be to obtain time synchronization error correction values at multiple moments, calculate the average value of multiple time synchronization error correction values, and then correct the time synchronization error according to the average value.

In one embodiment, the time synchronization error corrected multiple times may be learned and analyzed by deep learning, and then when the time synchronization error is obtained, the time synchronization error may be corrected according to the historical correction method.

After correcting the time synchronization error between the GPS navigation system and the INS navigation system, the GPS/INS tightly integrated navigation system can obtain accurate positioning information, thereby improving navigation accuracy and positioning speed.

The embodiment of the present application obtains the measured values of pseudorange and pseudorange rate of the global positioning system, obtains the predicted values of pseudorange and pseudorange rate of the inertial navigation system at the same time as the global positioning system, calculates the measurement information of the combined positioning system of the global positioning system and the inertial navigation system according to the measured values of the pseudorange and pseudorange rate and the predicted values of the pseudorange and pseudorange rate, and eliminates the time synchronization error between the inertial navigation system and the global positioning system according to the measurement information to correct the positioning of the combined positioning system of the global positioning system and the inertial navigation system. By eliminating the time synchronization error between the global positioning system and the inertial navigation system, the navigation accuracy and positioning speed are improved.

Please refer to Figure 2, which is a second flow chart of the navigation method provided in the embodiment of the present application. The navigation method in the embodiment of the present application eliminates the time synchronization error in the GPS/INS tightly integrated navigation system to improve the navigation accuracy and positioning speed of the GPS/INS tightly integrated navigation system.

In step 201, the measured values of pseudorange and pseudorange rate of the global positioning system are obtained. This step is the same as step 101 and will not be described in detail here.

In step 202, system parameters of a combined positioning system of a global positioning system and an inertial navigation system are obtained, wherein the system parameters include a navigation solution, satellite parameters, clock error and clock drift of the inertial navigation system.

It is understandable that the predicted values of the pseudorange and pseudorange rate of the inertial navigation system cannot be directly output from the inertial navigation processor, and need to be calculated to obtain the predicted values of the pseudorange and pseudorange rate of the inertial navigation system. It should be noted that the satellite parameters include parameters such as the position and speed of the satellite.

In step 203, the predicted values of the pseudorange and pseudorange rate of the inertial navigation system at the same time as the global positioning system are calculated according to the system parameters.

In one embodiment, the current attitude, velocity, and position of the inertial navigation system can be obtained by calculating the data output by the inertial measurement unit (IMU), and then the telegram obtained by the satellite receiving system is solved to obtain information such as the satellite position and velocity. Finally, the predicted values of the pseudorange and pseudorange rate of the inertial navigation system are calculated based on the satellite position and velocity and the position and velocity information of the inertial navigation system.

In one embodiment, the estimated values of the pseudorange and pseudorange rate of the inertial navigation system may be obtained by using the unit line-of-sight distance vector between the satellite and the user and the navigation solution in the inertial navigation system.

For example, the navigation solution of the inertial navigation system is first transformed into a first conversion value and a second conversion value through a lever arm coordinate transformation, wherein the transformation formula is as follows:

in, is the first conversion value, is the second conversion value, Ω is the antisymmetric matrix of the angular velocity vector, C is the coordinate transformation matrix, L is the phase center arm between systems, and W is the system noise vector.

Then, the state vector (position vector, velocity vector, partial derivative of time error) estimated by the inertial navigation system is calculated based on the second conversion value and the unit line of sight distance vector between the satellite and the user. The estimated state vector can be used to calculate the velocity, acceleration and jerk. The formula is as follows:

where _uk is the unit line-of-sight distance vector between the satellite and the user.

Finally, the predicted values of pseudorange and pseudorange rate of the inertial navigation system are obtained according to the position, speed and other information output by the satellite and the inertial measurement unit. The predicted value formula of pseudorange and pseudorange rate of the inertial navigation system obtained is as follows:

in is the pseudorange prediction value of the inertial navigation system, It is the measured value of the pseudo-range rate of the inertial navigation system. The subscripts l represent the arm coordinate system, i represents the inertial coordinate system, e represents the Earth-centered Earth-fixed coordinate system, j represents the number of satellites, a represents the parameters of satellite attributes, a represents acceleration, C represents the coordinate transformation matrix, and U represents the unit vector and the line of sight unit vector.

In step 204, sampling data of the GPS pseudorange and pseudorange rate within the sampling period of the inertial navigation system are obtained according to the measured values of the GPS pseudorange and pseudorange rate and the Taylor formula.

Due to the difference in sampling frequencies between the GPS navigation system and the INS navigation system and the time delay in information transmission to the combined filter, there is a time synchronization problem, namely, time synchronization error, between the pseudorange and pseudorange rate measurements of the GPS navigation system and the pseudorange and pseudorange rate of the INS navigation system predicted by parameters such as the INS navigation solution.

At this time, it is necessary to expand the corresponding pseudorange and pseudorange rate using Taylor's formula to predict the pseudorange and pseudorange rate of GPS and inertial navigation at the same time, and then perform corresponding data processing.

First, the pseudorange and pseudorange rate of the GPS navigation system are expanded using Taylor's formula at the time t = kT _s and retained to the second order, where T _s is the sampling period of the INS navigation system. The pseudorange and pseudorange rate of the GPS navigation system can be expressed by the following formula:

At t = kT _s -δt, the pseudorange and pseudorange rate of the GPS navigation system can be expressed by the following formula:

It should be noted that is the pseudo-range measurement value of the GPS navigation system, is the measured value of the pseudorange rate of the GPS navigation system, where δt is the time synchronization error between the GPS navigation system and the INS navigation system.

In step 205, measurement information within a sampling period is acquired based on the sampled data of the pseudorange and pseudorange rate of the global positioning system and the sampled data of the pseudorange and pseudorange rate of the inertial navigation system within a sampling period of the inertial navigation system.

In one embodiment, the measured values of pseudorange and pseudorange rate of the GPS navigation system at a certain moment can be obtained, and the predicted values of pseudorange and pseudorange rate of the INS navigation system at the same moment as the GPS navigation system can be obtained, and then the measured value and predicted value of the pseudorange are subtracted, and the measured value and predicted value of the pseudorange rate are subtracted to obtain measurement information. The obtained measurement information matrix is as follows:

Where k is the kth sampling time, Z is the measurement vector, and m is the number of satellites. Represents the measurement information of pseudorange, Indicates the measurement information of the pseudorange rate.

In one embodiment, measurement information within a sampling period _Ts of the INS navigation system may be acquired to analyze the time synchronization error within the sampling period _Ts of the INS navigation system.

In step 206, the measurement vector is linearized according to the measurement information and the extended Kalman filter to obtain a measurement matrix.

The measurement vector is a nonlinear function of the error state vector. It can be linearized using the extended Kalman filter (EFK) to grasp the law of sampled data changes and obtain the measurement matrix. The linearization formula of the extended Kalman filter is:

In one embodiment, the pseudorange and pseudorange rate are weakly correlated with the attitude error, acceleration bias, and gyro bias. The pseudorange and velocity error, and the pseudorange rate and position error are also weakly correlated. These items are ignored when linearizing the measurement matrix, so that the approximate measurement matrix obtained is:

The time synchronization error between the GPS navigation system and the INS navigation system can be obtained based on the approximate measurement matrix.

In step 207, the time synchronization error between the global positioning system and the inertial navigation system is obtained according to the measurement matrix, and the time synchronization error is eliminated to correct the positioning of the combined positioning system of the global positioning system and the inertial navigation system.

After obtaining the time synchronization error, the time synchronization error between the INS navigation system and the GPS navigation system within the sampling period can be eliminated so that the GPS/INS tightly combined navigation system can accurately locate. In addition, through the navigation method recorded in the embodiment of the present application, the amount of calculation when calculating the time synchronization error can be reduced, thereby realizing a fast positioning function.

In one embodiment, the correction method may be to obtain time synchronization error correction values at multiple moments, calculate an average value of the multiple time synchronization error correction values, and then correct the time synchronization error according to the average value.

In one embodiment, the time synchronization error corrected multiple times may be learned and analyzed by deep learning, and then when the time synchronization error is obtained, the time synchronization error may be corrected according to the historical correction method.

The embodiment of the present application obtains the measured values of the pseudorange and pseudorange rate of the global positioning system, obtains the predicted values of the pseudorange and pseudorange rate of the inertial navigation system at the same time as the global positioning system, obtains the sampling data of the pseudorange and pseudorange rate of the global positioning system within the sampling period of the inertial navigation system according to the measured values of the pseudorange and pseudorange rate of the global positioning system and the Taylor formula, and obtains the measurement information within the sampling period according to the sampling data of the pseudorange and pseudorange rate of the global positioning system and the sampling data of the pseudorange and pseudorange rate of the inertial navigation system within the sampling period of the inertial navigation system.

Finally, the measurement vector is linearized according to the measurement information and the extended Kalman filter to obtain the measurement matrix, and then the time synchronization error between the global positioning system and the inertial navigation system is obtained according to the measurement matrix, and the time synchronization error is eliminated to correct the positioning of the combined positioning system of the global positioning system and the inertial navigation system.

By eliminating the time synchronization error between the global positioning system and the inertial navigation system, the navigation accuracy and positioning speed are improved.

Please refer to Figure 3, which is a scene diagram of the navigation method provided by the embodiment of the present application. In Figure 3, a three-dimensional full-dynamic carrier motion track including acceleration, deceleration, turning and climbing is designed, and then the time synchronization error and other errors between the INS navigation system and the GPS navigation system are obtained.

Considering the time synchronization error problem, the GPS/INS tightly combined system equation and measurement equation are simulated. The error analysis data in the following table are obtained:

Among them, Max is the maximum error value, SD is the mean error value, and Mean is the minimum error value.

Please refer to Figure 4 for details. Figure 4 is an error comparison curve diagram provided in an embodiment of the present application, wherein curve A is an error curve without compensating for the time synchronization error, and curve B is an error curve with compensating for the time synchronization error.

As shown in Figure 4, the time synchronization error of the GPS/INS navigation system is compensated by the above navigation method, and the positioning and speed control performance of the navigation system are significantly improved. It can also be seen that the impact of time asynchrony on navigation performance is related to the dynamic level of the carrier. The higher the dynamic level of the carrier, that is, when it has a larger speed and acceleration, the more significant the time synchronization problem is. The model designed based on the distance domain can effectively suppress the time synchronization problem, and the position and velocity errors after compensation are basically consistent with the error results without the time synchronization problem.

Correspondingly, the embodiment of the present application further provides a navigation device, as shown in the first structural diagram of the navigation device in FIG5 . The navigation device includes: a first acquisition module 510 , a second acquisition module 520 , a calculation module 530 and a correction module 540 .

The first acquisition module 510 is used to acquire the measured values of pseudorange and pseudorange rate of the global positioning system.

The first acquisition module 510 may adopt a first preset algorithm to acquire, for example, a pseudo-range measurement value in a GPS ranging processor is acquired by code tracking.

The pseudo-range rate measurement value of the GPS navigation system can be obtained by a second preset algorithm, for example, obtaining the pseudo-range rate measurement value in the GPS ranging processor from the carrier wave. It should be noted that the first preset algorithm and the second preset algorithm are not limited to the above algorithms.

In some embodiments, the pseudorange and pseudorange rate in the GPS navigation system may also be measured values actively output by the GPS ranging processor.

The second acquisition module 520 is used to acquire the predicted values of the pseudorange and pseudorange rate of the inertial navigation system at the same time as the global positioning system.

In one embodiment, the predicted values of the pseudorange and pseudorange rate of the inertial navigation system at the same time as the global positioning system can be obtained based on the system parameters in the INS navigation system, wherein the system parameters may include the inertial navigation solution of the INS navigation system, the estimated clock error and clock drift, and satellite parameters, wherein the satellite parameters include the satellite position and velocity calculated by the message, etc.

In one embodiment, the inertial navigation solution of the INS navigation system may be transformed into a lever arm coordinate to obtain a first conversion value and a second conversion value, and the estimated values of the pseudorange and pseudorange rate of the INS navigation system may be calculated based on the first conversion value, the second conversion value and the unit line of sight distance vector of the satellite and the electronic device.

It should be noted that the second acquisition module 520 also includes an acquisition submodule 521 and a first calculation submodule 522. Please refer to FIG. 6 for details. FIG. 6 is a second structural diagram of the navigation device provided in the embodiment of the present application.

The acquisition submodule 521 is used to acquire the system parameters of the combined positioning system of the global positioning system and the inertial navigation system, wherein the system parameters include the navigation solution, satellite parameters, clock error and clock drift of the inertial navigation system.

It is understandable that the predicted values of the pseudorange and pseudorange rate of the inertial navigation system cannot be directly output from the inertial navigation processor, and the predicted values of the pseudorange and pseudorange rate of the inertial navigation system need to be calculated. The system parameters of the combined positioning system of the global positioning system and the inertial navigation system can be obtained through the acquisition submodule 521. It should be noted that the satellite parameters include parameters such as the position and speed of the satellite.

The first calculation submodule 522 is used to calculate the predicted values of the pseudorange and pseudorange rate of the inertial navigation system at the same time as the global positioning system according to the system parameters.

In one embodiment, the first calculation submodule 522 can calculate the data output by the inertial measurement unit (IMU) to obtain the current attitude, speed, and position of the inertial navigation system, and then interpret the message obtained by the satellite receiving system to obtain information such as the satellite position and speed. Finally, the predicted values of the pseudorange and pseudorange rate of the inertial navigation system are calculated based on the satellite position, speed and the position and speed information of the inertial navigation system.

In one embodiment, the first calculation submodule 522 may use the unit line-of-sight distance vector between the satellite and the user and the navigation solution in the inertial navigation system to obtain the estimated values of the pseudorange and pseudorange rate of the inertial navigation system.

For example, the navigation solution of the inertial navigation system is first transformed into a first conversion value and a second conversion value through a lever arm coordinate transformation, wherein the transformation formula is as follows:

in, is the first conversion value, is the second conversion value, Ω is the antisymmetric matrix of the angular velocity vector, C is the coordinate transformation matrix, L is the phase center arm between systems, and W is the system noise vector.

Then, the state vector (position vector, velocity vector, partial derivative of time error) estimated by the inertial navigation system is calculated based on the second conversion value and the unit line of sight distance vector between the satellite and the user. The estimated state vector can be used to calculate the velocity, acceleration and jerk. The formula is as follows:

where _uk is the unit line-of-sight distance vector between the satellite and the user.

Finally, the predicted values of pseudorange and pseudorange rate of the inertial navigation system are obtained according to the position, speed and other information output by the satellite and the inertial measurement unit. The predicted value formula of pseudorange and pseudorange rate of the inertial navigation system obtained is as follows:

in is the pseudorange prediction value of the inertial navigation system, It is the measured value of the pseudo-range rate of the inertial navigation system. The subscripts l represent the arm coordinate system, i represents the inertial coordinate system, e represents the Earth-centered Earth-fixed coordinate system, j represents the number of satellites, a represents the parameters of satellite attributes, a represents acceleration, C represents the coordinate transformation matrix, and U represents the unit vector and the line of sight unit vector.

The calculation module 530 is used to calculate the measurement information of the combined positioning system of the global positioning system and the inertial navigation system according to the measured values of the pseudorange and the pseudorange rate and the predicted values of the pseudorange and the pseudorange rate.

The calculation module 530 can obtain measurement information based on the measured values of the pseudorange and pseudorange rate of the GPS navigation system and the predicted values of the pseudorange and pseudorange rate of the INS navigation system. For example, the measurement value of the pseudorange of the GPS navigation system is subtracted from the predicted value of the pseudorange of the INS navigation system, and the measurement value of the pseudorange rate of the GPS navigation system is subtracted from the predicted value of the pseudorange rate of the INS navigation system to obtain the measurement information.

The calculation module 530 includes a sampling submodule 531 and a second calculation submodule 532 .

The sampling submodule 531 is used to obtain the sampling data of the GPS pseudorange and pseudorange rate within the sampling period of the inertial navigation system according to the measured values of the GPS pseudorange and pseudorange rate and the Taylor formula.

Due to the difference in sampling frequencies between the GPS navigation system and the INS navigation system and the time delay in information transmission to the combined filter, there is a time synchronization problem, namely, time synchronization error, between the pseudorange and pseudorange rate measurements of the GPS navigation system and the pseudorange and pseudorange rate of the INS navigation system predicted by parameters such as the INS navigation solution.

At this time, it is necessary to expand the corresponding pseudorange and pseudorange rate using Taylor's formula to predict the pseudorange and pseudorange rate of GPS and inertial navigation at the same time, and then perform corresponding data processing.

First, the sampling submodule 531 expands the pseudorange and pseudorange rate of the GPS navigation system at the time t= _kTs using the Taylor formula and retains it to the second order, where _Ts is the sampling period of the INS navigation system. The pseudorange and pseudorange rate of the GPS navigation system can be expressed by the following formula:

At t = kT _s -δt, the pseudorange and pseudorange rate of the GPS navigation system can be expressed by the following formula:

It should be noted that is the pseudo-range measurement value of the GPS navigation system, is the measured value of the pseudorange rate of the GPS navigation system, where δt is the time synchronization error between the GPS navigation system and the INS navigation system.

The second calculation submodule 532 acquires measurement information within the sampling period according to the sampling data of the pseudorange and pseudorange rate of the global positioning system and the sampling data of the pseudorange and pseudorange rate of the inertial navigation system within the sampling period of the inertial navigation system.

In one embodiment, the measured values of pseudorange and pseudorange rate of the GPS navigation system at a certain moment can be obtained, and the predicted values of pseudorange and pseudorange rate of the INS navigation system at the same moment as the GPS navigation system can be obtained, and then the measured value and predicted value of the pseudorange are subtracted, and the measured value and predicted value of the pseudorange rate are subtracted to obtain measurement information. The obtained measurement information matrix is as follows:

Where k is the kth sampling time, Z is the measurement vector, and m is the number of satellites. Represents the measurement information of pseudorange, Indicates the measurement information of the pseudorange rate.

In one embodiment, measurement information within a sampling period _Ts of the INS navigation system may be acquired to analyze the time synchronization error within the sampling period _Ts of the INS navigation system.

The correction module 540 is used to eliminate the time synchronization error between the inertial navigation system and the global positioning system according to the measurement information, so as to correct the positioning of the combined positioning system of the global positioning system and the inertial navigation system.

The correction module 540 includes an analysis submodule 541 and a correction submodule 542 .

The analysis submodule 541 is used to linearize the measurement vector according to the measurement information and the extended Kalman filter to obtain a measurement matrix.

The measurement vector is a nonlinear function of the error state vector. The analysis submodule 541 can linearize it using an extended Kalman filter (EFK) to grasp the law of sampled data changes and obtain a measurement matrix. The extended Kalman filter linearization formula is:

In one embodiment, the pseudorange and pseudorange rate are weakly correlated with the attitude error, acceleration bias, and gyro bias. The pseudorange and velocity error, and the pseudorange rate and position error are also weakly correlated. These items are ignored when linearizing the measurement matrix, so that the approximate measurement matrix obtained is:

The time synchronization error between the GPS navigation system and the INS navigation system can be obtained based on the approximate measurement matrix.

The correction submodule 542 obtains the time synchronization error between the global positioning system and the inertial navigation system according to the measurement matrix, and eliminates the time synchronization error to correct the positioning of the combined positioning system of the global positioning system and the inertial navigation system.

After obtaining the time synchronization error, the correction submodule 542 can eliminate the time synchronization error between the INS navigation system and the GPS navigation system within the sampling period so that the GPS/INS tightly combined navigation system can accurately locate. In addition, through the navigation method described in the embodiment of the present application, the amount of calculation when calculating the time synchronization error can be reduced, thereby realizing a fast positioning function.

In one embodiment, the correction method may be to obtain time synchronization error correction values at multiple moments, calculate an average value of the multiple time synchronization error correction values, and then correct the time synchronization error according to the average value.

In one embodiment, the time synchronization error corrected multiple times may be learned and analyzed by deep learning, and then when the time synchronization error is obtained, the time synchronization error may be corrected according to the historical correction method.

The embodiment of the present application obtains the measured values of pseudorange and pseudorange rate of the global positioning system, obtains the predicted values of pseudorange and pseudorange rate of the inertial navigation system at the same time as the global positioning system, calculates the measurement information of the combined positioning system of the global positioning system and the inertial navigation system according to the measured values of the pseudorange and pseudorange rate and the predicted values of the pseudorange and pseudorange rate, and eliminates the time synchronization error between the inertial navigation system and the global positioning system according to the measurement information to correct the positioning of the combined positioning system of the global positioning system and the inertial navigation system. By eliminating the time synchronization error between the global positioning system and the inertial navigation system, the navigation accuracy and positioning speed are improved.

Accordingly, an embodiment of the present application further provides an electronic device, as shown in FIG7 , the terminal may include a display unit 701, an input unit 702, a memory 703 including one or more computer-readable storage media, a processor 704 including one or more processing cores, a power supply 705, and a sensor 706 and other components. Those skilled in the art will appreciate that the electronic device structure shown in FIG7 does not constitute a limitation on the electronic device, and may include more or fewer components than shown in the figure, or combine certain components, or arrange components differently. Among them:

The display unit 701 can be used to display information input by the user or information provided to the user and various graphical user interfaces of the terminal, which can be composed of graphics, text, icons, videos and any combination thereof. The display unit 701 may include a display panel, and optionally, the display panel may be configured in the form of a liquid crystal display (LCD), an organic light-emitting diode (OLED), etc. Further, the touch-sensitive surface may cover the display panel, and when the touch-sensitive surface detects a touch operation on or near it, it is transmitted to the processor 704 to determine the type of touch event, and then the processor 704 provides corresponding visual output on the display panel according to the type of touch event. Although in FIG. 7, the touch-sensitive surface and the display panel are implemented as two independent components to implement input and output functions, in some embodiments, the touch-sensitive surface and the display panel can be integrated to implement input and output functions.

The input unit 702 can be used to receive input digital or character information, and generate keyboard, mouse, joystick, optical or trackball signal input related to user settings and function control. Specifically, in a specific embodiment, the input unit 702 may include a touch-sensitive surface and other input devices. The touch-sensitive surface, also known as a touch display screen or a touch pad, can collect the user's touch operations on or near it (such as the user's operation on or near the touch-sensitive surface using any suitable object or accessory such as a finger, a stylus, etc.), and drive the corresponding connection device according to a pre-set program. Optionally, the touch-sensitive surface may include a touch detection device and a touch controller. Among them, the touch detection device detects the user's touch orientation, detects the signal brought by the touch operation, and transmits the signal to the touch controller; the touch controller receives the touch information from the touch detection device, converts it into the touch point coordinates, and then sends it to the processor 704, and can receive and execute the command sent by the processor 704. In addition, the touch-sensitive surface can be implemented using multiple types such as resistive, capacitive, infrared and surface acoustic waves. In addition to the touch-sensitive surface, the input unit 702 may also include other input devices. Specifically, other input devices may include, but are not limited to, one or more of a physical keyboard, function keys (such as a volume control key, a switch key, etc.), a trackball, a mouse, a joystick, and the like.

The memory 703 can be used to store software programs and modules. The processor 608 executes various functional applications and data processing by running the software programs and modules stored in the memory 703. The memory 703 may mainly include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application required for at least one function (such as a sound playback function, an image playback function, etc.), etc.; the data storage area may store data created according to the use of the terminal (such as audio data, a phone book, etc.), etc. In addition, the memory 703 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, or other volatile solid-state storage devices. Accordingly, the memory 703 may also include a memory controller to provide the processor 703 and the input unit 702 with access to the memory 703.

The processor 704 is the control center of the terminal. It uses various interfaces and lines to connect various parts of the entire mobile phone. By running or executing software programs and/or modules stored in the memory 703 and calling data stored in the memory 703, it executes various functions of the terminal and processes data, thereby monitoring the mobile phone as a whole. Optionally, the processor 704 may include one or more processing cores; preferably, the processor 704 may integrate an application processor and a modem processor, wherein the application processor mainly processes the operating system, user interface, and application programs, and the modem processor mainly processes wireless communications. It is understandable that the above-mentioned modem processor may not be integrated into the processor 704.

The terminal also includes a power supply 705 (such as a battery) for supplying power to each component. Preferably, the power supply can be logically connected to the processor 704 through a power management system, so that the power management system can manage charging, discharging, and power consumption management. The power supply 705 can also include one or more DC or AC power supplies, recharging systems, power failure detection circuits, power converters or inverters, power status indicators, and other arbitrary components.

The terminal may also include at least one sensor 706, such as a light sensor, a motion sensor, and other sensors. Specifically, the light sensor may include an ambient light sensor and a proximity sensor, wherein the ambient light sensor may adjust the brightness of the display panel according to the brightness of the ambient light, and the proximity sensor may turn off the display panel and/or backlight when the terminal is moved to the ear. As a type of motion sensor, the gravity acceleration sensor can detect the magnitude of acceleration in each direction (generally three axes), and can detect the magnitude and direction of gravity when stationary. It can be used for applications that identify the posture of the mobile phone (such as horizontal and vertical screen switching, related games, magnetometer posture calibration), vibration recognition related functions (such as pedometer, tapping), etc.; as for other sensors that can be configured in the terminal, such as gyroscopes, barometers, hygrometers, thermometers, infrared sensors, etc., they will not be repeated here.

Although not shown, the terminal may also include a camera, a Bluetooth module, etc., which will not be described in detail here. Specifically in this embodiment, the processor 704 in the terminal will load the executable files corresponding to the processes of one or more applications into the memory 703 according to the following instructions, and the processor 704 will run the applications stored in the memory 703 to achieve various functions:

Obtaining GPS pseudorange and pseudorange rate measurements;

Obtaining predicted values of pseudorange and pseudorange rate of an inertial navigation system at the same time as the global positioning system;

Calculating measurement information of the combined positioning system of the global positioning system and the inertial navigation system according to the measured values of the pseudorange and the pseudorange rate and the predicted values of the pseudorange and the pseudorange rate;

The time synchronization error between the inertial navigation system and the global positioning system is eliminated according to the measurement information to correct the positioning of the combined positioning system of the global positioning system and the inertial navigation system.

A person of ordinary skill in the art will appreciate that all or part of the steps in the various methods of the above embodiments may be completed by instructions, or by controlling related hardware through instructions. The instructions may be stored in a computer-readable storage medium and loaded and executed by a processor.

To this end, an embodiment of the present application provides a storage medium in which a plurality of instructions are stored, and the instructions can be loaded by a processor to execute the steps in any navigation method provided in the embodiment of the present application. For example, the instructions can execute the following steps:

Obtaining GPS pseudorange and pseudorange rate measurements;

Obtaining predicted values of pseudorange and pseudorange rate of an inertial navigation system at the same time as the global positioning system;

Calculating measurement information of the combined positioning system of the global positioning system and the inertial navigation system according to the measured values of the pseudorange and the pseudorange rate and the predicted values of the pseudorange and the pseudorange rate;

The time synchronization error between the inertial navigation system and the global positioning system is eliminated according to the measurement information to correct the positioning of the combined positioning system of the global positioning system and the inertial navigation system.

The specific implementation of the above operations can be found in the previous embodiments, which will not be described in detail here.

The storage medium may include: a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, etc.

Since the instructions stored in the storage medium can execute the steps in any navigation method provided in the embodiments of the present application, the beneficial effects that can be achieved by any navigation method provided in the embodiments of the present application can be achieved. Please refer to the previous embodiments for details and will not be repeated here.

The above is a detailed introduction to a navigation method, device, electronic device and storage medium provided in an embodiment of the present application. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea; at the same time, for technical personnel in this field, according to the idea of the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims (9)

1. A method of navigation, the method comprising:

Acquiring a pseudo range and a measured value of a pseudo range rate of a global positioning system;

Acquiring a pseudo range and a predicted value of a pseudo range rate of an inertial navigation system at the same moment as the global positioning system;

Calculating measurement information of the combined global positioning system and inertial navigation system according to the measured values of the pseudo range and the pseudo range rate and the predicted values of the pseudo range and the pseudo range rate, wherein the measurement information comprises the following components: acquiring sampling data of the global positioning system pseudo range and the pseudo range rate in the inertial navigation system sampling period according to the measured values of the global positioning system pseudo range and the pseudo range rate and a Taylor formula; acquiring measurement information in a sampling period according to the sampling data of the global positioning system pseudo range and the pseudo range rate and the sampling data of the inertial navigation system pseudo range and the pseudo range rate in the inertial navigation system sampling period;

And eliminating time synchronization errors of the inertial navigation system and the global positioning system according to the measurement information so as to correct the positioning of the global positioning system and inertial navigation system combined positioning system.

2. The navigation method of claim 1, wherein the obtaining the pseudorange and the pseudorange rate measurements of the global positioning system comprises:

And acquiring a pseudo-range measurement value of the global positioning system according to a first preset algorithm, and acquiring a pseudo-range measurement value of the global positioning system according to a second preset algorithm.

3. The navigation method of claim 1, wherein the obtaining the predicted values of the pseudo range and the pseudo range rate of the inertial navigation system at the same time as the global positioning system comprises:

acquiring system parameters of the global positioning system and inertial navigation system combined positioning system, wherein the system parameters comprise navigation solutions, satellite parameters, clock errors and Zhong Piao of the inertial navigation system;

And calculating the predicted values of the pseudo range and the pseudo range rate of the inertial navigation system at the same moment with the global positioning system according to the system parameters.

4. The navigation method of claim 1, wherein the removing the time synchronization error of the combined global positioning system and inertial navigation system based on the measurement information to correct the positioning of the combined global positioning system and inertial navigation system comprises:

linearizing a measurement vector according to the measurement information and the extended Kalman filter to obtain a measurement matrix;

And acquiring a time synchronization error between the global positioning system and the inertial navigation system according to the measurement matrix, and eliminating the time synchronization error to correct the positioning of the global positioning system and the inertial navigation system combined positioning system.

5. A navigation device, the device comprising:

the first acquisition module is used for acquiring the pseudo range and the measured value of the pseudo range rate of the global positioning system;

The second acquisition module is used for acquiring a pseudo range and a predicted value of a pseudo range rate of an inertial navigation system at the same moment with the global positioning system;

the calculation module is used for calculating measurement information of the combined positioning system of the global positioning system and the inertial navigation system according to the measured values of the pseudo range and the pseudo range rate and the predicted values of the pseudo range and the pseudo range rate;

the correction module is used for eliminating time synchronization errors of the inertial navigation system and the global positioning system according to the measurement information so as to correct the positioning of the global positioning system and inertial navigation system combined positioning system;

Wherein the computing module comprises:

the sampling sub-module is used for acquiring sampling data of the global positioning system pseudo range and the pseudo range rate in the inertial navigation system sampling period according to the measured values of the global positioning system pseudo range and the pseudo range rate and a Taylor formula;

and the second calculation sub-module is used for acquiring measurement information in the sampling period according to the sampling data of the pseudo range and the pseudo range rate of the global positioning system and the sampling data of the pseudo range and the pseudo range rate of the inertial navigation system in the sampling period of the inertial navigation system.

6. The navigation device of claim 5, wherein the second acquisition module comprises:

The acquisition sub-module is used for acquiring system parameters of the global positioning system and inertial navigation system combined positioning system, wherein the system parameters comprise navigation solutions, satellite parameters, clock errors and Zhong Piao of the inertial navigation system;

And the first calculation sub-module is used for calculating the predicted values of the pseudo range and the pseudo range rate of the inertial navigation system at the same moment with the global positioning system according to the system parameters.

7. The navigation device of claim 5, wherein the correction module comprises:

The analysis submodule is used for linearizing the measurement vector according to the measurement information and the extended Kalman filter so as to obtain a measurement matrix;

And the correction sub-module is used for acquiring the time synchronization error between the global positioning system and the inertial navigation system according to the measurement matrix and eliminating the time synchronization error so as to correct the positioning of the global positioning system and the inertial navigation system combined positioning system.

8. An electronic device, comprising:

a memory storing executable program code, a processor coupled to the memory;

The processor invokes the executable program code stored in the memory to perform the steps in the navigation method of any one of claims 1 to 4.

9. A storage medium storing a plurality of instructions adapted to be loaded by a processor to perform the steps of the navigation method of any one of claims 1 to 4.