CN117008166A

CN117008166A - Positioning quality evaluation method, apparatus, device, storage medium, and program product

Info

Publication number: CN117008166A
Application number: CN202210465564.7A
Authority: CN
Inventors: 苏景岚
Original assignee: Tencent Technology Shenzhen Co Ltd
Current assignee: Tencent Technology Shenzhen Co Ltd
Priority date: 2022-04-29
Filing date: 2022-04-29
Publication date: 2023-11-07

Abstract

The present application relates to a positioning quality evaluation method, apparatus, computer device, storage medium and computer program product. The method relates to a navigation positioning technology, and can be applied to electronic maps, internet of vehicles, automatic driving and intelligent traffic scenes. The method comprises the following steps: acquiring satellite observation data of a current epoch of a terminal, wherein the satellite observation data comprises an observation pseudo range; acquiring a terminal positioning result obtained by resolving according to satellite observation data; determining an observed pseudo-range residual error of the satellite according to the observed pseudo-range of the satellite and a terminal positioning result, and calculating a first type of statistical parameter related to the observed pseudo-range residual error; determining single-difference observation pseudo-range residual errors among satellites according to the observation pseudo-range of the satellites and the terminal positioning result, and calculating second-class statistical parameters about the single-difference observation pseudo-range residual errors; according to the first type of statistical parameters and the second type of statistical parameters, the positioning quality of the positioning result of the current epoch terminal is evaluated, and the accuracy of the positioning quality evaluation can be improved, so that the accuracy of the positioning result is improved.

Description

Positioning quality evaluation method, apparatus, device, storage medium, and program product

Technical Field

The present application relates to the field of computer technology, and in particular, to a positioning quality evaluation method, apparatus, computer device, storage medium, and computer program product.

Background

The global satellite navigation system GNSS (the Global Navigation Satellite System) is an air-based radio navigation positioning system that can provide all-weather 3-dimensional coordinates and velocity and time information to a user at any location on the earth's surface or near-earth space. Common satellite navigation systems are the GPS, BDS, GLONASS and GALILEO four-large satellite navigation systems. Satellite navigation systems have been widely used in communication, consumer entertainment, mapping, timing, vehicle management, and car navigation and information services.

The GNSS satellite positioning utilizes spatially distributed satellites and satellite observation data received by a terminal to estimate a terminal positioning result, so that real-time positioning service is improved for the terminal, and under general conditions, the deviation between the terminal positioning result and the true position of the terminal is within an acceptable range, but the deviation is often influenced by various factors to have larger deviation with the true positioning result of the terminal, so that the terminal positioning result at the moment is inaccurate, and how to accurately and reasonably evaluate the terminal positioning quality to improve the accuracy of the positioning result is a problem to be solved.

Disclosure of Invention

In view of the foregoing, it is desirable to provide a positioning quality evaluation method, apparatus, computer device, computer readable storage medium, and computer program product that promote accuracy in evaluating a terminal positioning result.

In a first aspect, the present application provides a positioning quality assessment method. The method comprises the following steps:

acquiring satellite observation data of a current epoch of a terminal, wherein the satellite observation data comprises an observation pseudo range between the terminal and a satellite;

acquiring a terminal positioning result obtained by resolving according to the satellite observation data;

determining an observed pseudo-range residual error of a satellite according to the observed pseudo-range of the satellite and the terminal positioning result, and calculating a first type of statistical parameter related to the observed pseudo-range residual error;

according to the satellite observation pseudo-range and the terminal positioning result, determining single-difference observation pseudo-range residual errors among satellites, and calculating second-class statistical parameters related to the single-difference observation pseudo-range residual errors;

and according to the first type of statistical parameters and the second type of statistical parameters, evaluating the positioning quality of the terminal positioning result in the current epoch.

In a second aspect, the application further provides a positioning quality evaluation device. The device comprises:

The acquisition module is used for acquiring satellite observation data of the current epoch of the terminal, wherein the satellite observation data comprises an observation pseudo range between the terminal and a satellite; acquiring a terminal positioning result obtained by resolving according to the satellite observation data;

the first statistical module is used for determining an observed pseudo-range residual error of the satellite according to the observed pseudo-range of the satellite and the terminal positioning result, and calculating a first type of statistical parameter related to the observed pseudo-range residual error;

the second statistical module is used for determining single-difference observation pseudo-range residual errors among satellites according to the observation pseudo-ranges of the satellites and the terminal positioning result, and calculating second-class statistical parameters related to the single-difference observation pseudo-range residual errors;

and the quality evaluation module is used for evaluating the positioning quality of the terminal positioning result in the current epoch according to the first type statistics and the second type statistics parameters.

In one embodiment, the apparatus further comprises: the pseudo-range observation equation construction module is used for calculating the transmitting time of the satellite signals according to the observed pseudo-range between the current epoch terminal and the satellite and the receiving time of the satellite signals received by the terminal; inquiring satellite real-time navigation ephemeris according to the transmitting time to obtain a satellite position and a satellite clock error corresponding to the current epoch satellite; constructing a pseudo-range observation equation between the terminal and the satellite according to the observed pseudo-range of each satellite, the satellite position and the satellite clock error, the position of the terminal to be estimated and the clock error of the terminal to be estimated; and solving the pseudo-range observation equation according to the satellite observation data to obtain a terminal positioning result.

In one embodiment, the first statistics module includes a positioning resolving unit, configured to calculate, in a multiple iteration process of performing least square resolving on the pseudo-range observation equation based on the satellite observation data, an estimated distance between the terminal and the satellite according to a satellite position corresponding to a current epoch satellite, a satellite clock difference, a terminal position estimated value obtained in a previous iteration, and a terminal clock difference estimated value; calculating residual errors between the observed pseudo-ranges and the estimated distances of all satellites, performing coarse difference elimination on the residual errors based on quartiles, screening target observed pseudo-ranges from the observed pseudo-ranges of all satellites, and performing least square solution of current iteration by using a pseudo-range observation equation formed by the target observed pseudo-ranges.

In one embodiment, the satellite observation data further includes a signal-to-noise ratio of the observation pseudo-range, and the first statistics module includes a positioning calculation unit, configured to obtain, in a current iteration process of least squares calculation, an estimated parameter of a previous iteration, where the estimated parameter includes an estimated position and an estimated clock difference; acquiring a target satellite screened after the previous iteration; calculating the variance of the observed pseudo range of the target satellite according to the signal-to-noise ratio of the observed pseudo range of the target satellite and the altitude angle of the satellite determined based on the satellite position corresponding to the target satellite and the terminal estimated position of the previous iteration; constructing an observed pseudo-range variance matrix according to the observed pseudo-range variances of all target satellites; determining a pseudo-range observation equation of the current iteration based on satellite observation data of the target satellite; acquiring a differential matrix of a pseudo-range observation equation of the current iteration aiming at parameters to be estimated, wherein the parameters to be estimated comprise the position of a terminal to be estimated and the clock error of the terminal to be estimated; determining an estimated parameter correction of the current iteration according to the differential matrix, the observed pseudo-range variance matrix and the pseudo-range observation residual error of the target satellite of the current iteration; and correcting the estimated parameters of the previous iteration according to the estimated parameter correction quantity of the current iteration to obtain the estimated parameters of the current iteration.

In one embodiment, the positioning resolving unit is further configured to continue the iterative process when the estimated parameter correction of the current iteration is greater than a first preset threshold; when the correction amount of the estimated parameters of the current iteration is smaller than a first preset threshold value, determining a post-test observation pseudo-range residual sequence and a post-test observation pseudo-range variance matrix of the current iteration based on the estimated parameters of the current iteration, and calculating chi-square test statistics according to the post-test observation pseudo-range variance matrix and the post-test observation pseudo-range residual sequence; when the chi-square test statistic is smaller than a second preset threshold, stopping iteration, and obtaining a positioning result of the terminal according to the estimation parameter of the current iteration; and when the chi-square test statistic is larger than a second preset threshold, carrying out normal distribution test on the post-test observation pseudo-range residual sequence based on the post-test observation pseudo-range residual covariance matrix of the current iteration, and continuing the iteration process by using the screened observation pseudo-range of the target satellite after eliminating the observation pseudo-range which does not pass the normal distribution test.

In one embodiment, the first statistics module includes a residual parameter statistics unit, configured to calculate a positioning distance between the terminal and the satellite according to a satellite position and a satellite clock difference corresponding to the current epoch satellite, and the calculated terminal position and the calculated terminal clock difference; calculating residual errors between the observed pseudo-ranges of all satellites and the corresponding positioning distances to obtain an observed pseudo-range residual error sequence; and calculating the square root and the absolute intermediate bit difference of the observed pseudo-range residual sequence.

In one embodiment, the residual parameter statistics unit is further configured to calculate an observed pseudo-range variance of the satellite according to a signal-to-noise ratio of the observed pseudo-range and an altitude angle of the satellite determined based on a satellite position corresponding to the current epoch satellite and the resolved terminal position; constructing an observed pseudo-range variance matrix according to the observed pseudo-range variances of the satellites; calculating an error in unit weight of the observed pseudo-range residual sequence according to the observed pseudo-range residual sequence and the observed pseudo-range variance matrix; and outputting the sequence of the observed pseudo-range residuals, and unit weight center error, square root and absolute center difference of the observed pseudo-range residuals.

In one embodiment, the second statistical module includes a single difference residual error construction unit, configured to determine a reference satellite from the observed satellites of the terminal in the current epoch; for each non-reference satellite in the observation satellites, calculating an observation single difference between the observation pseudo range of the non-reference satellite and the observation pseudo range of the reference satellite, and calculating a positioning single difference between the positioning distance corresponding to the non-reference satellite and the positioning distance corresponding to the reference satellite; and determining a single-difference observation pseudo-range residual sequence according to the residual between the observation single difference corresponding to each non-reference satellite and the positioning single difference.

In one embodiment, the second statistics module includes a single-difference residual parameter statistics unit, configured to calculate, according to a single-difference observed pseudo-range residual sequence formed by single-difference observed pseudo-range residuals of each non-reference satellite, a square root and an absolute medium bit difference of the single-difference observed pseudo-range residual sequence; calculating a post-observation pseudo-range variance of the satellite according to the signal-to-noise ratio of the observation pseudo-range, the altitude angle of the satellite determined based on the satellite position corresponding to the current epoch satellite and the terminal position obtained by resolving, and the error in the unit weight of the first type of statistical parameters about the observation pseudo-range residual; constructing a post-test observed pseudo-range variance matrix according to the post-test observed pseudo-range variances of the satellites; calculating an error in a unit weight of the single-difference observation pseudo-range residual sequence according to the checked observation pseudo-range variance matrix and the single-difference observation pseudo-range residual sequence; and outputting a unit weight middle error, a square root and an absolute middle bit difference of the single-difference observed pseudo-range residual.

In one embodiment, the first type of statistical parameter comprises an error in unit weight with respect to an observed pseudorange residual; the second class of statistical parameters includes errors in unit weights for the single difference observed pseudorange residuals; the device also comprises a terminal scene judging module, a terminal scene judging module and a terminal scene judging module, wherein the terminal scene judging module is used for determining a scene where the terminal is located according to errors in unit weights related to the observed pseudo-range residual errors and errors in unit weights related to the single-difference observed pseudo-range residual errors; the quality evaluation module is also used for evaluating the positioning quality of the terminal positioning result in the current epoch according to the scene in which the terminal is positioned.

In one embodiment, the terminal scene decision module is further configured to calculate a post-test parameter covariance matrix of the current epoch and a post-test parameter covariance matrix of the previous epoch; calculating the relative variance of the posterior variance according to the posterior parameter covariance matrix of the adjacent calendar elements; and determining the scene where the terminal is located according to the relative variance after test, the error in the unit weight related to the observed pseudo-range residual and the error in the unit weight related to the single-difference observed pseudo-range residual.

In one embodiment, the first type of statistical parameter comprises an error in unit weight with respect to an observed pseudorange residual; the terminal scene judging module is further used for calculating the satellite observation pseudo-range variance according to the signal-to-noise ratio of the observation pseudo-range of the current epoch and the satellite altitude angle determined based on the satellite position corresponding to the current epoch satellite and the terminal position obtained through resolving; constructing an observed pseudo-range variance matrix according to the observed pseudo-range variances of the satellites; acquiring a differential matrix of the pseudo-range observation equation for parameters to be estimated, wherein the parameters to be estimated comprise the position of a terminal to be estimated and the clock error of the terminal to be estimated; and calculating a post-test parameter covariance matrix of the current epoch according to the observed pseudo-range variance matrix, the differential matrix and the error in the unit weight of the current epoch relative to the observed pseudo-range residual.

In one embodiment, the first type of statistical parameter includes a unit weight error, a square root, and an absolute median difference with respect to an observed pseudorange residual; the second type of statistical parameters comprise unit weight middle error, square mean root and absolute middle difference of the single difference observation pseudo-range residual error; the quality evaluation module is further used for counting the relative variation of errors in unit weights of the current epoch and the previous epoch respectively about the observed pseudo-range residual error, the relative variation of Fang Jun roots and the relative variation of absolute intermediate differences; counting the relative variation of errors in unit weights of the current epoch and the previous epoch respectively about the single-difference observation pseudo-range residual error, the relative variation of Fang Jun roots and the relative variation of absolute intermediate bit difference; and evaluating the positioning quality of the terminal positioning result of the current epoch according to the relative variation between the first type of statistical parameters corresponding to the current epoch and the previous epoch and the relative variation between the second type of statistical parameters corresponding to the current epoch.

In one embodiment, the quality assessment module is further configured to determine a maximum of the post-test variance relative variation, the relative variation of the error in unit weight with respect to the observed pseudorange residual, the relative variation of Fang Jun and the relative variation of the absolute middle bit difference, the relative variation of the error in unit weight with respect to the single difference observed pseudorange residual, the relative variation of Fang Jun and the relative variation of the absolute middle bit difference; comparing the determined maximum value with a threshold value corresponding to each level of positioning track smoothness, and determining the positioning track smoothness corresponding to the current epoch; and evaluating the positioning quality of the terminal positioning result of the current epoch according to the smoothness of the positioning track.

In one embodiment, the satellite observation data further includes a signal-to-noise ratio of the observed pseudorange, the apparatus further comprising: the signal-to-noise ratio information statistics module is used for acquiring the signal-to-noise ratio of the observed pseudo range corresponding to each satellite of the satellite transmission signals received by the terminal from the satellite observation data; outputting statistical information about the signal-to-noise ratio according to the maximum value, the minimum value, the standard deviation and the absolute middle bit difference in the signal-to-noise ratio of the observed pseudo range of each satellite;

and the quality evaluation module is also used for evaluating the positioning quality of the terminal positioning result in the current epoch according to the statistical information about the signal-to-noise ratio.

In a third aspect, the present application also provides a computer device. The computer device comprises a memory storing a computer program and a processor which when executing the computer program performs the steps of:

In a fourth aspect, the present application also provides a computer-readable storage medium. The computer readable storage medium having stored thereon a computer program which when executed by a processor performs the steps of:

In a fifth aspect, the present application also provides a computer program product. The computer program product comprises a computer program which, when executed by a processor, implements the steps of:

According to the positioning quality evaluation method, the positioning quality evaluation device, the computer equipment, the storage medium and the computer program product, the terminal positioning result is obtained by obtaining satellite observation data of the current epoch of the terminal and calculating the observation pseudo range based on the satellite observation data, and then the observation pseudo range residual error can be determined according to the satellite observation pseudo range and the terminal positioning result, and the first type of statistical parameters related to the observation pseudo range residual error are calculated; in addition, the single-difference observation pseudo-range residual error is determined through the observation pseudo-range of the satellite and the terminal positioning result obtained through the calculation, and further the second type of statistical parameters related to the single-difference observation pseudo-range residual error can be calculated, so that the first type of statistical parameters and the second type of statistical parameters are combined to serve as positioning quality evaluation indexes, the positioning quality of the terminal positioning result of the current epoch can be accurately evaluated, and the accuracy of the terminal positioning result is improved.

Drawings

FIG. 1 is a diagram of an application environment for a positioning quality assessment method in one embodiment;

FIG. 2 is a general framework diagram of a positioning quality assessment method in one embodiment;

FIG. 3 is a flow chart of a positioning quality evaluation method in one embodiment;

FIG. 4 is a flow diagram of constructing a pseudorange observation equation between a terminal and a satellite in one embodiment;

FIG. 5 is a flow diagram of a positioning solution in one embodiment;

FIG. 6 is a schematic diagram of an iterative flow of least squares positioning solution in one embodiment;

FIG. 7 is a flow chart of a first type of statistical parameters for calculating an observed pseudo-range residual in one embodiment;

FIG. 8 is a flow chart of outputting first type of statistics in one embodiment;

FIG. 9 is a flow diagram of determining single difference observed pseudorange residuals in one embodiment;

FIG. 10 is a flow chart of outputting a second type of statistics in one embodiment;

FIG. 11 is a schematic diagram of determining the smoothness of a current positioning track of a terminal in one embodiment;

FIG. 12 is a schematic diagram of a scenario in which a terminal is located in one embodiment;

FIG. 13 is a block diagram of a positioning quality evaluation apparatus in one embodiment;

fig. 14 is an internal structural diagram of a computer device in one embodiment.

Detailed Description

The present application will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present application more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the application.

Concepts related to the embodiments of the present application will be explained first:

satellite positioning equipment: electronic device for processing satellite signals and measuring the geometrical distance between the device and the satellite (observed pseudo-range) and the doppler effect of the satellite signals (doppler observation). The satellite positioning device generally comprises an antenna, a satellite signal receiving loop, a baseband signal processing module and the like, and a terminal integrated with the satellite positioning device can calculate the current position coordinate of the terminal according to the pseudo-range observation value and the Doppler observation value. The satellite positioning device is widely applied to the fields of map navigation, mapping, position service, deep space exploration and the like, such as smart phone map navigation, high-precision geodetic survey, civil aviation and the like.

Satellite observations by a satellite positioning device, comprising an observed pseudo-range between the terminal and the satellite, a pseudo-range rate and an accumulated distance delta (ADR, accumulated delta range), wherein the observed pseudo-range measures a geometric distance of the satellite to the positioning device; the pseudo-range rate observation value measures Doppler effect generated by relative motion between positioning equipment and satellites; ADR measures the change in geometric distance from the satellite to the positioning device;

Global satellite navigation system GNSS (the Global Navigation Satellite System): is an air-based radio navigation positioning system capable of providing all-weather 3-dimensional coordinates and velocity and time information to a user at any location on the earth's surface or near-earth space. Common satellite navigation systems are the four major satellite navigation systems GPS (Global Positioning System ), BDS (BeiDou Navigation Satellite System, beidou satellite navigation system in china), GLONASS (GLOBAL NAVIGATION SATELLITE SYSTEM, global satellite navigation system) and GALILEO (Galileo satellite navigation system ). Satellite navigation systems have been widely used in communication, consumer entertainment, mapping, timing, vehicle management, and car navigation and information services.

Basic principle of GNSS satellite positioning: and calculating a terminal positioning result by using spatially distributed satellites and distance intersection of the satellites and the terminal, simultaneously receiving more than 4 GNSS satellite signals by the terminal, and measuring the geometric distance between the observed satellites and the terminal by the terminal through satellite positioning equipment, thereby calculating the terminal space position and the receiver clock error by using a distance intersection method.

Least squares method: the least squares method (also known as least squares) is a mathematical optimization technique. It finds the best functional match for the data by minimizing the sum of squares of the errors. The unknown data can be easily obtained by the least square method, and the sum of squares of errors between the obtained data and the actual data is minimized.

The positioning quality evaluation method provided by the embodiment of the application can be applied to an application environment shown in figure 1. Wherein the terminal 102 communicates with the server 104 via a network. The data storage system may store data that the server 104 needs to process. The data storage system may be integrated on the server 104 or may be located on the cloud or other servers.

In a specific application scenario, the terminal 102 may be the above-mentioned satellite positioning device, and the terminal 102 is integrated with a global satellite navigation system positioning chip, where the global satellite navigation system positioning chip may be used to process satellite signals and perform accurate positioning on a user of the terminal 102, and may be used for location services. Specifically, at each epoch, the terminal 102 obtains satellite observation data for each satellite in space, including an observation pseudo-range, a signal-to-noise ratio of a satellite signal, and the like, according to the integrated global satellite navigation system positioning chip. In addition, the terminal 102 obtains the satellite real-time navigation ephemeris from the server, wherein the satellite real-time navigation ephemeris is an expression describing the position and the speed of the space vehicle, and can be used for inquiring the position and the satellite clock difference of the satellite, and the positioning result of the terminal 102 is determined based on the satellite observation data and the satellite position and the satellite clock difference obtained by inquiring the satellite real-time navigation ephemeris. The epoch is an observation epoch, specifically, an observation time corresponding to satellite observation data, satellite observation data obtained at different observation times are different, and for comparing or processing satellite observation data at different times, such time is referred to as an observation epoch.

Then, the terminal 102 may further perform positioning quality evaluation on the positioning result, output the positioning result when the quality evaluation result indicates that the positioning quality of the positioning result is better, and filter the positioning result when the quality evaluation result indicates that the positioning quality of the positioning result is worse.

In one embodiment, the terminal 102 obtains satellite observation data for a current epoch of the terminal, the satellite observation data including an observed pseudorange between the terminal and a satellite; acquiring a terminal positioning result obtained by resolving according to satellite observation data; determining an observed pseudo-range residual error of the satellite according to the observed pseudo-range of the satellite and a terminal positioning result, and calculating a first type of statistical parameter related to the observed pseudo-range residual error; according to the satellite observation pseudo-range and the terminal positioning result, determining single-difference observation pseudo-range residual errors among satellites, and calculating second-class statistical parameters about the single-difference observation pseudo-range residual errors; and according to the first type of statistical parameters and the second type of statistical parameters, evaluating the positioning quality of the positioning result of the current epoch terminal.

Optionally, a target client supporting a positioning function, such as an electronic map, is installed and operated on the terminal 102, and the positioning quality evaluation method provided in the embodiment of the present application may be executed by the target client, and the target client determines whether to filter the positioning result of the current epoch according to the positioning quality evaluation result of the current epoch, thereby filtering the positioning result with lower positioning quality and poorer positioning accuracy, and outputting and displaying the positioning result with higher positioning accuracy. Optionally, the positioning quality evaluation method provided by the embodiment of the present application may also be executed by the server 104 that provides the service for the target client, where the server 104 may obtain satellite observation data of the current epoch of the terminal from the terminal 102, calculate the positioning result of the terminal based on the satellite observation data and perform positioning quality evaluation, and feed back the positioning quality evaluation result to the terminal 102, so as to instruct the terminal 102 to filter the positioning result with lower positioning quality and poorer positioning accuracy.

The terminal 102 may be, but not limited to, various desktop computers, notebook computers, smart phones, tablet computers, intelligent voice interaction devices, internet of things devices and portable wearable devices, and the internet of things devices may be smart speakers, smart televisions, smart air conditioners, smart vehicle terminals, etc. The portable wearable device may be a smart watch, smart bracelet, headset, or the like. The embodiment of the application can be applied to various scenes, including but not limited to cloud technology, artificial intelligence, intelligent transportation, auxiliary driving and the like. The server 104 may be implemented as a stand-alone server or as a server cluster of multiple servers.

Fig. 2 is a schematic diagram of an overall framework of a positioning quality evaluation method according to an embodiment of the present application. Referring to fig. 2, the figure divides the positioning quality assessment process into the following modules: the system comprises a satellite signal-to-noise ratio statistics module 202, a single epoch least square solution module 204, a single difference observation residual statistics module 206, a to-be-estimated parameter post-test variance relative change amount calculation module 208, a positioning track smoothness discrimination module 210, a terminal scene discrimination module 212 and a terminal positioning quality assessment module 214.

The satellite signal-to-noise ratio statistics module is used for counting the information such as the maximum value, the minimum value, the standard deviation, the absolute middle potential difference and the like of the signal-to-noise ratio of the satellite according to the signal-to-noise ratio of the satellite in satellite observation data, and the statistical parameters related to the signal-to-noise ratio can be independently used for evaluating the positioning quality or can be combined with other statistical parameters for evaluating the positioning quality.

The single epoch least square calculation module is used for combining a pseudo-range observation equation and satellite observation data to carry out single epoch least square calculation, obtaining a satellite positioning result, obtaining a satellite pseudo-range observation residual error based on the positioning result, and outputting first type statistical information about the pseudo-range observation residual error, including square root, unit weight error, absolute intermediate level difference and the like.

The single-difference observation residual error statistical module is used for calculating a posterior error model according to the prior error model and the errors in the unit weights of the pseudo-range observation residual errors, determining the single-difference observation pseudo-range residual errors based on positioning results, and outputting second type statistical information about the single-difference observation pseudo-range residual errors by utilizing the posterior error model, wherein the second type statistical information comprises square root, errors in the unit weights and absolute intermediate bit differences.

And the parameter post-test variance relative change amount to be estimated is used for calculating the post-test variance relative change amount of the adjacent epoch parameters.

The positioning track smoothness judging module is used for judging the positioning track smoothness according to one or more of the following parameters: the method comprises the steps of satellite signal-to-noise ratio statistical parameters, post-test variance relative variation of adjacent epoch position parameters, relative variation of first type statistical parameters calculated by least square of adjacent epochs, and relative variation of second type statistical information of single epoch single-difference observation pseudo-range residual errors.

The terminal scene judging module is used for judging the scene of the terminal according to one or more of the following parameters: the satellite signal-to-noise ratio statistical parameters, errors in unit weights calculated by single epoch least square solution, errors in unit weights of single-difference observation pseudo-range residual errors, relative variance after test of adjacent epoch position parameters, and the like.

The terminal positioning quality evaluation module is used for performing positioning quality evaluation independently according to one or more of the parameters output by the modules, and can also perform positioning quality evaluation by combining one or more of the parameters, the smoothness of the positioning track and the terminal scene to obtain a quality evaluation result of the terminal positioning result output by the single epoch least square calculation module, and filtering the positioning result with poor positioning index or obvious deviation.

In one embodiment, as shown in fig. 3, a positioning quality evaluation method is provided, and the method is applied to the terminal 102 in fig. 1 for illustration, and includes the following steps:

step 302, acquiring satellite observation data of a current epoch of a terminal, wherein the satellite observation data comprises an observation pseudo range between the terminal and a satellite; and acquiring a terminal positioning result obtained by resolving according to satellite observation data.

In one embodiment, the terminal may obtain satellite observation data of a current epoch of the terminal, the satellite observation data includes an observation pseudo-range between the terminal and a satellite, a pseudo-range observation equation between the terminal and the satellite is constructed according to the observation pseudo-range, and the terminal may calculate the pseudo-range observation equation according to the satellite observation data of the current epoch of the terminal, so as to obtain a terminal positioning result.

The epoch is an observation epoch, specifically, the observation time corresponding to the satellite observation data, the satellite observation data obtained at different observation times are different, and for comparing or processing the satellite observation data at different times, such time is called an observation epoch. For example, the j+1th epoch is the current epoch, the j-th epoch is the previous epoch, and the j-th epoch is two epochs adjacent to the j+1th epoch.

The satellite observation data of the current epoch of the terminal is the corresponding observation data of the satellites received by the current epoch of the terminal, and comprises information such as the observation pseudo range of each satellite, the signal-to-noise ratio of the satellite signals received by each satellite and the like. The observed pseudoranges are the geometric distances between each satellite observed by the terminal and the terminal, respectively, and typically the total number of each satellite is at least 4. The pseudoranges are called because the geometric range contains errors due to clock errors and atmospheric refraction delays, rather than "true ranges". The clock error comprises a satellite clock error and a terminal clock error, the clock error refers to the difference between the clock reading and the real system time, the satellite clock error refers to the difference between the satellite clock and the real system time, and the terminal clock error refers to the difference between the terminal clock and the real system time.

As shown in fig. 4, in one embodiment, constructing a pseudorange observation equation between a terminal and a satellite from an observed pseudorange includes:

step 402, calculating the transmitting time of the satellite signal according to the observed pseudo range between the current epoch terminal and the satellite and the receiving time of the satellite signal received by the terminal.

Assuming that the current epoch of the terminal receives satellite signals transmitted by n satellites, the terminal can acquire the observed pseudo ranges of the n satellites, and the observed pseudo range of the satellite i is recorded asThe reception time of the satellite signal can be recorded asAnd respectively determining the transmitting time of satellite signals of all satellites observed by the current epoch terminal according to the observed pseudo-range, the receiving time and the light speed value.

And step 404, inquiring satellite real-time navigation ephemeris according to the transmitting time to obtain the satellite position and satellite clock error corresponding to the current epoch satellite.

Specifically, the terminal may query the satellite real-time navigation ephemeris based on the transmission time to obtain the satellite position and satellite clock difference of each satellite observed by the current epoch terminal. In one embodiment, the terminal may send an ephemeris acquisition request to the satellite positioning base station server, and after receiving the ephemeris acquisition request sent by the terminal, the satellite positioning base station server may acquire the satellite real-time navigation ephemeris from the satellite ephemeris database, and transmit the satellite real-time navigation ephemeris to the terminal in a binary stream form, where the terminal queries, according to the time of transmission of the satellite signals of each satellite observed by the current epoch, the satellite position and the satellite clock error of each satellite observed by the current epoch from the acquired satellite real-time navigation ephemeris.

And step 406, constructing a pseudo-range observation equation between the terminal and the satellite according to the observed pseudo-range of each satellite, the satellite position and the satellite clock difference, the position of the terminal to be estimated and the clock difference of the terminal to be estimated.

Specifically, the terminal may construct a pseudo-range observation equation between the terminal and the satellite based on an a priori error model formed by a relationship between the observed pseudo-range and the true distance between the satellite and the terminal. As mentioned previously, the observed pseudoranges contain clock errors and errors due to atmospheric refraction delays, and based on this a priori relationship, a pseudorange observation equation is constructed as follows:

wherein,observed pseudorange representing satellite i, r _u Representing the position of the terminal to be estimated, r ⁱ (i=1, 2,., n) denotes the satellite position of satellite i, dt _r Representing the terminal clock difference to be estimated, dt ⁱ (i=1, 2,., n) denotes the satellite clock difference for satellite i, c is the speed of light in vacuum, ζ ⁱ (i=1, 2,) n is the error correction of satellite i, i.e. the error due to the atmospheric refraction delay, including the error correction of ionosphere, troposphere and earth rotation, which can be calculated from an empirical model. The satellite position and the terminal position are expressed in the form of three-dimensional coordinates (x, y, z).

And step 304, determining an observed pseudo-range residual error of the satellite according to the observed pseudo-range of the satellite and the terminal positioning result, and calculating a first type of statistical parameter related to the observed pseudo-range residual error.

Specifically, the terminal may perform single epoch positioning calculation on the pseudo-range observation equation by using a least square method, where the positioning calculation process needs to perform multiple iterations based on satellite observation data (including signal-to-noise ratio of the observed pseudo-range and the observed pseudo-range) and estimated parameters obtained by previous iterations, until an iteration stop condition is satisfied, and a terminal positioning result is obtained, where the terminal positioning result includes a terminal position and a terminal clock error. And the terminal can determine the observed pseudo-range residual error of each satellite based on the observed pseudo-range of each satellite, the satellite position, the satellite clock error and the terminal position and the terminal clock error obtained by positioning calculation, so as to obtain an observed pseudo-range residual error sequence, and calculate a first type of statistical parameters related to the observed pseudo-range residual error according to the observed pseudo-range residual error sequence. The observed pseudo-range residual is calculated based on the terminal positioning result obtained by the positioning calculation, and thus may be referred to as a post-inspection observed pseudo-range residual.

It should be noted that, if the terminal receives satellite signals of n satellites in the current epoch, in the multiple iterative process of positioning calculation, the terminal may reject satellites with poor quality of satellite observation data, then the terminal positioning result obtained in the last iteration may be obtained by calculating q (q is smaller than n) satellites in the n satellites, then the subsequent determination of satellite observation pseudo-range residual according to the terminal positioning result obtained by calculating, and the calculation of the first type of statistical parameters about the observation pseudo-range residual and step 306 are all implemented based on satellite observation data of the q satellites. That is, satellite observation data with low quality may be removed in the iterative process, and then satellite observation data of the selected satellites and the terminal positioning result are filtered, and the first type of statistical parameter and the second type of statistical parameter are calculated, so that the accuracy of the positioning quality index is further improved. However, for convenience of explanation, the terminal positioning result obtained by the last iteration is obtained by resolving satellite observation data based on n satellites.

For example, the observed pseudorange residual v for satellite i _i The method can be calculated by the following formula:

wherein,observed pseudorange representing satellite i +.>Representing the positioning distance of satellite i, wherein +.>Representing the calculated terminal position, r ⁱ Representing the satellite position of satellite i>Representing the calculated terminal clock difference, dt ⁱ Satellite clock error and ζ representing satellite i ⁱ For satellite iError correction. The terminal receives satellite signals transmitted by n satellites in the current epoch, and then the terminal can calculate the observed pseudo-range residuals of the n satellites respectively according to the above method to form an observed pseudo-range residual sequence V:

the first type of statistical parameters are mathematical statistical parameters of the observed pseudo-range residuals of each satellite, and at least comprise a unit weight middle error delta, a square root gamma and an absolute middle bit difference tau of an observed pseudo-range residual sequence. The essence of the sequence of the observed pseudo-range residuals is the difference between the observed pseudo-range of the satellite and the positioning distance, if the residuals are near zero and the jitter is small, the quality of the observed pseudo-range is good, otherwise, if the residuals are large, the quality of the observed pseudo-range is poor. The first type of statistical parameters obtained based on the sequence of the observed pseudo-range residuals may reflect the quality of satellite observed data including the observed pseudo-range, thereby indirectly reflecting the positioning quality of the terminal positioning result.

And 306, determining single-difference observation pseudo-range residual errors among satellites according to the observation pseudo-ranges of the satellites and the terminal positioning result, and calculating second-class statistical parameters about the single-difference observation pseudo-range residual errors.

In one embodiment, the terminal may determine a single-difference observed pseudorange residual from the observed pseudoranges of the satellites and the positioning distances determined based on the terminal positioning results, and calculate a second type of statistical parameter for the single-difference observed pseudorange residual based on the tested observed pseudorange variance matrix and the single-difference observed pseudorange residual. That is, after the terminal obtains the terminal positioning result through the positioning calculation of the single epoch, the terminal may determine the single-difference observed pseudo-range residual, and calculate the second type of statistical parameter related to the single-difference observed pseudo-range residual based on the checked observed pseudo-range variance matrix.

Specifically, the terminal may combine the posterior error model and the error in the unit weight related to the observed pseudo-range residual error in the first type of statistical parameters, calculate to obtain the posterior observed pseudo-range variance of the satellite, and construct the posterior observed pseudo-range variance matrix S.

The terminal may select a reference satellite from n satellites that receive satellite signals from the current epoch, where other satellites in the n satellites form a pair of satellites with the reference satellite, and a total of n-1 pairs of satellites may be formed. For any pair of satellites, single-difference observed pseudo-range residuals of the pair of satellites are calculated, and a single-difference observed pseudo-range residual sequence M can be obtained according to the single-difference observed pseudo-range residuals of each pair of satellites.

The second type of statistical parameter is a mathematical statistical parameter related to a single-difference observed pseudo-range residual sequence, and at least comprises an error delta in unit weight, a square root delta gamma and an absolute median difference delta tau of the single-difference observed pseudo-range residual sequence. The single-difference observation pseudo-range residual sequence is essentially the difference between the observation single difference and the positioning single difference of a pair of satellites, if the residual is near a zero value and the jitter is small, the observation single difference can well eliminate errors caused by various influences, the quality of the observation pseudo-range is better, and based on the single-difference observation pseudo-range residual sequence M and the checked observation pseudo-range variance matrix S, the obtained second type of statistical parameters can reflect the quality of satellite observation data including the observation pseudo-range, so that the positioning quality of a terminal positioning result is indirectly reflected.

And step 308, evaluating the positioning quality of the positioning result of the current epoch terminal according to the first type of statistical parameters and the second type of statistical parameters.

The first type of statistical parameter and the second type of statistical parameter can reflect the quality of satellite observation data, and the terminal positioning result is obtained by performing positioning calculation based on the satellite observation data, if the quality of the satellite observation data is low, the terminal positioning result obtained by the calculation is obviously poor in positioning quality, so that the first type of statistical parameter and the second type of statistical parameter can reflect the positioning quality of the terminal positioning result to a certain extent.

The terminal can carry out quality evaluation on the terminal positioning result based on the first type of statistical parameters and the second type of statistical parameters, and whether the terminal positioning result is better or worse is judged, so that whether the terminal positioning result is filtered out is judged.

In one embodiment, the terminal may further evaluate the positioning quality of the positioning result of the terminal of the current epoch based on the relative variation between the first type of statistical parameters corresponding to each of the adjacent epochs and the relative variation between the second type of statistical parameters corresponding to each of the adjacent epochs.

In one embodiment, the terminal may further evaluate the positioning quality of the positioning result of the current epoch terminal according to at least one of the first type of statistical parameter, the second type of statistical parameter, the relative variation between the first type of statistical parameter corresponding to each of the current epoch and the previous epoch, and the relative variation between the second type of statistical parameter corresponding to each of the current epoch and the previous epoch.

In one embodiment, the terminal may further determine a positioning track smoothness of the current epoch according to the relative variation between the first type of statistical parameters and the relative variation between the second type of statistical parameters of the adjacent epochs, and evaluate the positioning quality of the positioning result of the terminal of the current epoch according to the positioning track smoothness.

In one embodiment, the terminal may further determine a scene in which the terminal is located according to the error in the unit weight with respect to the observed pseudo-range residual and the error in the unit weight with respect to the single-difference observed pseudo-range residual; and evaluating the positioning quality of the positioning result of the current epoch terminal according to the scene of the terminal.

In one embodiment, the terminal may further calculate a statistic parameter of the signal-to-noise ratio of the observed pseudo-range, and output statistic information about the signal-to-noise ratio according to the statistic parameter of the signal-to-noise ratio, including a maximum value, a minimum value, a standard deviation, and an absolute medium bit difference in the signal-to-noise ratio of the observed pseudo-range of each satellite.

As mentioned above, the terminal may perform positioning quality assessment according to one or more of the previous statistical parameters, and may further perform positioning quality assessment in combination with one or more of the above statistical parameters, the relative variation of the statistical parameters, the smoothness of the positioning track, and the terminal scene, to obtain a quality assessment result of the terminal positioning result output by the single epoch least square calculation module, and filter the positioning result with poor positioning index or obvious deviation.

According to the positioning quality evaluation method, satellite observation data of the current epoch of the terminal are obtained, so that the terminal positioning result is obtained by resolving the satellite observation data based on the observation pseudo range in the satellite observation data, and further, an observation pseudo range residual error can be determined according to the satellite observation pseudo range and the terminal positioning result, and a first type of statistical parameter related to the observation pseudo range residual error is calculated; in addition, the single-difference observation pseudo-range residual error is determined through the observation pseudo-range of the satellite and the terminal positioning result obtained through the calculation, and further the second type of statistical parameters related to the single-difference observation pseudo-range residual error can be calculated, so that the first type of statistical parameters and the second type of statistical parameters are combined to serve as positioning quality evaluation indexes, the positioning quality of the terminal positioning result of the current epoch can be accurately evaluated, and the accuracy of the terminal positioning result is improved.

FIG. 5 is a flow diagram of a positioning solution for a pseudorange observation equation based on satellite observation data in one embodiment. Referring to fig. 5, the steps include:

step 502, in the current iteration process of least square solution, obtaining estimation parameters of the previous iteration, wherein the estimation parameters comprise estimation positions and estimation clock differences; and obtaining the target satellite screened after the previous iteration.

The least square calculated parameters to be estimated comprise the positions of the terminals to be estimated and the clock differences of the terminals to be estimated:

assuming that the previous iteration is the kth iteration, when the previous iteration is the kth+1 iteration, after the current iteration starts, the terminal obtains the estimated parameters of the previous iterationWherein r is _u,k Terminal estimated position, dt, representing previous iteration _r,k The terminal estimate clock difference representing the previous iteration. And when the iteration is performed for the first time, the terminal acquires a preset initial estimation parameter, and the iteration is started from the initial estimation parameter.

In addition, each iteration may remove a part of satellites with poor quality from n satellites, and the terminal further obtains a target satellite selected after the kth iteration, for example, the target satellite is m satellites in the n satellites, and performs the kth+1 iteration based on satellite observation data of the m satellites, where m is less than or equal to n and greater than 4.

Step 504, calculating the variance of the observed pseudo range of the target satellite according to the signal-to-noise ratio of the observed pseudo range of the target satellite and the altitude angle of the satellite determined based on the satellite position corresponding to the target satellite and the terminal estimated position of the previous iteration; and constructing an observed pseudo-range variance matrix according to the observed pseudo-range variances of the target satellites.

Terminal obtaining the terminal estimated position r of the kth iteration _u,k Estimating a position r according to the satellite position and the terminal position corresponding to each target satellite _u,k Calculating the corresponding altitude angle el of each target satellite ⁱ _k And then the terminal calculates the observed pseudo-range variance of the target satellite according to the signal-to-noise ratio of the observed pseudo-range of the target satellite and the altitude angle:

wherein, _CNO ⁱ signal-to-noise ratio, el, of the observed pseudorange for satellite i (i=1, 2, …, m) ⁱ _k Representing the altitude of the kth iteration satellite i.

The terminal constructs an observation pseudo-range variance matrix of the kth iteration according to the observation pseudo-range variances of all target satellites determined by the previous iteration:

step 506, determining a pseudo-range observation equation for the current iteration based on satellite observation data of the target satellite.

The terminal determines a pseudo-range observation equation of the current iteration according to satellite observation data of m target satellites and the following formula:

Step 508, obtaining a differential matrix of the pseudo-range observation equation of the current iteration for parameters to be estimated, wherein the parameters to be estimated comprise the position of the terminal to be estimated and the clock error of the terminal to be estimated; and determining the estimated parameter correction of the current iteration according to the differential matrix, the observed pseudo-range variance matrix and the pseudo-range observation residual error of the target satellite of the current iteration.

The terminal calculates the partial derivative of the parameter to be estimated with respect to the pseudo-range observation equation of the current iteration to obtain a differential matrix of the parameter to be estimated:

in the method, in the process of the invention,a unit vector representing the terminal to satellite i;

the terminal calculates pseudo-range observation residual errors after the previous iteration of the m target satellites according to the terminal estimated position, the terminal estimated clock error, the satellite position and the satellite clock error corresponding to each target satellite of the previous iteration:

the terminal determines the estimated parameter correction of the current iteration according to the differential matrix, the observed pseudo-range variance matrix and the pseudo-range observation residual error of the target satellite of the current iteration:

step 510, correcting the estimated parameters of the previous iteration according to the estimated parameter correction amount of the current iteration to obtain the estimated parameters of the current iteration.

x _u,k+1 ＝x _u,k +Δx _ρ,k ；

Wherein,

in one embodiment, the resolving process may further include:

and when the estimated parameter correction amount of the iteration is larger than a first preset threshold value, continuing the iteration process. When the correction amount of the estimated parameters of the current iteration is smaller than a first preset threshold value, determining a post-test observation pseudo-range residual sequence and a post-test observation pseudo-range variance matrix of the current iteration based on the estimated parameters of the current iteration, and calculating chi-square test statistics according to the post-test observation pseudo-range variance matrix and the post-test observation pseudo-range residual sequence. And when the chi-square test statistic is smaller than a second preset threshold value, stopping iteration, and obtaining a positioning result of the terminal according to the estimation parameter of the current iteration. And when the chi-square test statistic is larger than a second preset threshold, carrying out normal distribution test on the post-test observation pseudo-range residual sequence based on the post-test observation pseudo-range residual covariance matrix of the current iteration, and after eliminating the observation pseudo-range which does not pass the normal distribution test, continuing the iteration process by utilizing the screened observation pseudo-range of the target satellite.

When the estimated parameter correction amount of the current iteration is greater than a first preset threshold, continuing the iteration process, that is, continuing the next iteration process on the basis of the terminal estimated parameter obtained by the current iteration when the estimated parameter correction amount of the current iteration is greater than the first preset threshold.

And when the estimated parameter correction amount of the iteration is smaller than a first preset threshold value, calculating chi-square test statistics. Specifically, for the m satellites, the calculation formula of the post-test observed pseudo-range residual sequence at the time of iteration is as follows:

in addition, the terminal acquires the terminal estimated position of the current iteration, calculates the altitude angle corresponding to each target satellite according to the satellite position corresponding to each target satellite and the terminal estimated position of the current iteration, and further calculates the post-observation pseudo-range variance of the current iteration according to the signal-to-noise ratio of the observation pseudo-range of the target satellite and the altitude angle:

wherein, _CNO ⁱ signal-to-noise ratio, el, of the observed pseudorange for satellite i (i=1, 2, …, m) _k+1 ⁱ Representing the altitude of satellite i calculated based on the estimated position of the terminal for the k+1 iteration.

The terminal constructs a post-test observation pseudo-range variance matrix according to the post-test observation pseudo-range variance of the current iteration:

And calculating chi-square test statistics s according to the tested observed pseudo-range variance matrix and the tested observed pseudo-range residual sequence, wherein the formula is as follows:

when the chi-square test statistic is greater than a second preset threshold, the terminal can further perform normal distribution test on the post-test observation pseudo-range residual sequence based on the post-test observation pseudo-range residual covariance matrix of the current iteration, reject the observation pseudo-range which does not pass the normal distribution test from the observation pseudo-ranges of m satellites, screen q satellites from the observation pseudo-ranges, and perform the next iteration process, namely the k+2th iteration, on the basis of the terminal estimation parameters obtained at the current time. And when the chi-square test statistic is smaller than a second preset threshold value, stopping iteration, and obtaining a positioning result of the terminal according to the estimation parameter of the current iteration.

And outputting a terminal positioning result obtained by positioning calculation when the whole iteration is finished:

wherein the method comprises the steps ofIndicates the terminal position +.>Indicating the terminal clock difference.

In one embodiment, the resolving process may further include: and when constructing the pseudo-range observation equation of the current iteration, performing coarse difference elimination on the observation pseudo-range of each satellite, and constructing the pseudo-range observation equation by using the observation pseudo-range after coarse difference elimination so as to perform positioning calculation of the current iteration and improve the positioning quality. The method specifically comprises the following steps: in a multiple iteration process of carrying out least square calculation on a pseudo-range observation equation based on satellite observation data, calculating an estimated distance between a terminal and a satellite according to a satellite position corresponding to a current epoch satellite, a satellite clock difference, a terminal position estimated value obtained in the previous iteration and a terminal clock difference estimated value; residual errors between the observed pseudo-ranges and the estimated distances of all satellites are calculated, coarse difference elimination is carried out on the residual errors based on quartiles, target observed pseudo-ranges are screened out from the observed pseudo-ranges of all satellites, and the least square solution of the current iteration is carried out by using a pseudo-range observation equation formed by the target observed pseudo-ranges.

In the previous iteration process, if m target satellites are screened out from n satellites observed by the terminal by eliminating the observed pseudo ranges which do not pass through normal distribution inspection, the coarse difference elimination mentioned in the embodiment is to further perform coarse difference elimination on the screened m target satellites to screen out the observed pseudo ranges with larger coarse difference, obtain p target satellites, and construct a pseudo range observation equation by using the p target satellites to perform least square solution of current iteration.

As shown in fig. 6, an iterative flow diagram of least squares solution in one embodiment is shown. Referring to fig. 6, the k+1 iteration starts, and an observed pseudo-range residual sequence is constructed based on satellite observation data and estimated parameters of the k iteration; performing coarse difference elimination on the constructed observation pseudo-range residual sequence based on quartiles; constructing a pseudo-range observation equation based on the satellite observation data with the rough differences removed, and calculating a differential matrix of the pseudo-range observation equation about estimated parameters; constructing an observed pseudo-range variance matrix based on the satellite positions and the terminal estimated positions of the kth iteration; calculating an estimated parameter correction amount according to the differential matrix, the observed pseudo-range variance matrix and the observed pseudo-range residual sequence, and updating an estimated parameter according to the estimated parameter correction amount to obtain an estimated parameter of the (k+1) th iteration; judging whether the estimated parameter correction is smaller than a first threshold; if not, starting the k+2 iteration, if so, calculating a post-test observation pseudo-range variance matrix and a post-test observation pseudo-range residual sequence according to the estimated parameters of the k+1 iteration, and calculating chi-square test statistics according to the post-test observation pseudo-range variance matrix and the post-test observation pseudo-range residual sequence; judging whether the chi-square test statistic is greater than a second threshold value, if so, calculating a post-test observation pseudo-range residual covariance matrix, carrying out normal distribution test on the post-test observation pseudo-range residual sequence according to the post-test observation pseudo-range residual covariance matrix, and after eliminating the observation pseudo-range which does not pass the normal distribution test, starting the k+2 iteration, if not, ending the whole resolving process, and outputting a terminal positioning result.

The following describes a specific calculation process of the first type of statistical parameters:

in one embodiment, as shown in fig. 7, determining an observed pseudo-range residual according to the terminal positioning result obtained by the calculation, calculating a first type of statistical parameter about the observed pseudo-range residual includes:

step 702, calculating the positioning distance between the terminal and the satellite according to the satellite position and the satellite clock difference corresponding to the current epoch satellite, and the calculated terminal position and the calculated terminal clock difference.

The positioning distance of each satellite can be calculated according to the satellite position, satellite clock error, satellite error correction, and the terminal position and terminal clock error in the terminal positioning result. For example, the positioning distance of satellite i can be calculated by the following formula:

Step 704, calculating residuals between the observed pseudo-ranges of each satellite and the corresponding positioning distances to obtain an observed pseudo-range residual sequence.

wherein,observed pseudorange representing satellite i +.>Representing the positioning distance of satellite i, wherein +.>Representing the calculated terminal position, r ⁱ Representing the satellite position of satellite i>Representing the calculated terminal clock difference, dt ⁱ Satellite clock error and ζ representing satellite i ⁱ Is the error correction for satellite i. The terminal receives satellite signals transmitted by n satellites in the current epoch, and then the terminal can calculate the observed pseudo-range residuals of the n satellites according to the above method to form an observed pseudo-range residual sequence v= { V1, V2, …, vn }:

step 706, calculating the square root, the absolute median difference and the unit weight error of the observed pseudo-range residual sequence.

The square root is obtained by summing squares of all values in the sequence of values, solving the average value of the squares, and squaring the squares. The Fang Jun calculation formula of the observed pseudo-range residual sequence is as follows:

the square root of the residual sequence of the observed pseudo-range reflects the coincidence degree of the observed pseudo-range and the positioning distance, the quality of the observed pseudo-range is reflected to a certain extent, and the smaller the square root is, the higher the quality of the observed pseudo-range is represented, and the higher the positioning quality of the positioning result obtained based on the observed pseudo-range is. For example, the terminal may perform quality evaluation on the terminal positioning result according to the magnitude of the root of the square, when the root of the square is smaller than or equal to a preset threshold, the positioning quality evaluation result of the terminal positioning result may be determined to be correct in positioning, when the root of the square is larger than a preset error threshold, the positioning quality evaluation result of the terminal positioning result may be determined to be incorrect in positioning, and error thresholds set in different precision evaluation modes may have differences, and the error thresholds may be manually set according to specific requirements.

The absolute intermediate position difference of the observed pseudo-range residual sequence is calculated as follows:

τ＝1.4826·Median({V ₁ -Median(V),V ₂ -Median(V),...,V _n -Median(V)})；

the absolute median is obtained by calculating the median of the numerical sequence, calculating the difference between each data in the numerical sequence and the median, and calculating the median of the differences. The absolute median may reflect the degree of fluctuation of the sequence of values. The absolute intermediate position difference of the observation pseudo-range residual sequence reflects the fluctuation degree of the observation pseudo-range, and the smaller the absolute intermediate position difference is, the smaller the fluctuation degree of the observation pseudo-range is, the higher the quality of the observation pseudo-range is, and the higher the positioning quality of a positioning result obtained based on the observation pseudo-range is.

In one embodiment, the satellite observation data further includes a signal-to-noise ratio of the observation pseudo-range, the observation pseudo-range residual is determined according to the terminal positioning result obtained by the calculation, and the first type of statistical parameters about the observation pseudo-range residual are calculated, and the method further includes: calculating the variance of the observed pseudo range of the satellite according to the signal-to-noise ratio of the observed pseudo range and the altitude angle of the satellite determined based on the satellite position corresponding to the current epoch satellite and the terminal position obtained by resolving; constructing an observed pseudo-range variance matrix according to the observed pseudo-range variances of the satellites; and calculating the error in the unit weight of the observed pseudo-range residual sequence according to the observed pseudo-range residual sequence and the observed pseudo-range variance matrix.

The calculation formula of the satellite observed pseudo-range variance is as follows:

wherein CNO ⁱ Signal-to-noise ratio, el, of the observed pseudorange for satellite i (i=1, 2, …, m) ⁱ The altitude of satellite i is determined based on the satellite position of satellite i and the terminal position.

The terminal constructs an observed pseudo-range variance matrix according to the observed pseudo-range variances of the satellites:

calculating according to the observed pseudo-range variance matrix and the observed pseudo-range residual error to obtain an error in the unit weight of the observed pseudo-range residual error:

the unit weight error is a middle error of a numerical value with the weight equal to 1 in the numerical sequence, and the middle error is an index for measuring the observation precision, so that the unit weight error can reflect the precision of the observation pseudo range, and the smaller the value is, the higher the precision of the observation pseudo range is, and the higher the positioning quality is. The terminal can evaluate the quality of the terminal positioning result according to the value of the error in the unit weight.

Fig. 8 is a schematic flow chart of calculating the first type of statistical information in one embodiment. Referring to fig. 8, after a terminal positioning result is obtained through positioning calculation, an observed pseudo-range variance matrix may be calculated according to a satellite position, a terminal position, and a signal-to-noise ratio of a satellite observed pseudo-range, an observed pseudo-range residual sequence may be calculated according to a satellite observed pseudo-range, a satellite position, a satellite clock error, a terminal position, and a terminal clock error, a square root γ and an absolute medium bit difference τ may be output according to the observed pseudo-range residual sequence, and a unit weight medium error δ may be output according to the observed pseudo-range variance matrix and the observed pseudo-range residual sequence.

The following describes a specific calculation procedure of the second type of statistical information:

in one embodiment, as shown in fig. 9, determining a single-difference observed pseudo-range residual between satellites according to the observed pseudo-range of the satellites and the terminal positioning result includes:

a reference satellite is determined from the observed satellites of the current epoch terminal, step 902.

The terminal may select a reference satellite from n satellites that receive satellite signals from the current epoch, where other satellites in the n satellites form a pair of satellites with the reference satellite, and a total of n-1 pairs of satellites may be formed. The reference satellite may be a satellite having a largest satellite altitude among the n satellites. The satellite altitude of the satellite represents the included angle between the connecting line of the satellite position and the terminal position and the horizontal plane of the terminal, and can be calculated according to the satellite position and the terminal position.

Step 904, for each non-reference satellite in the observed satellites, calculating an observed single difference between the observed pseudo-range of the non-reference satellite and the observed pseudo-range of the reference satellite, and calculating a positioning single difference between the positioning distance corresponding to the non-reference satellite and the positioning distance corresponding to the reference satellite.

For any pair of satellites, the terminal can calculate the difference between the observed pseudo ranges of the pair of satellites to obtain the observed single difference of the pair of satellites; and calculating the difference between the positioning distances of the pair of satellites to obtain a single difference between the positioning distances of the pair of satellites.

The positioning distance of each satellite can be calculated according to the satellite position, satellite clock error, satellite error correction, and the terminal position and terminal clock error in the positioning result. For example, the positioning distance of satellite i can be calculated by the following formula:

step 906, determining single-difference observed pseudo-range residual errors according to residual errors between the observed single differences and the positioning single differences corresponding to the non-reference satellites.

And the terminal calculates the residual error between the single difference observed by the pair of satellites and the single difference positioned to obtain the single difference observed pseudo-range residual error of the pair of satellites. And obtaining a single-difference observation pseudo-range residual sequence according to the single-difference observation pseudo-range residual of each pair of satellites.

Taking the reference satellite as the satellite 1 for illustration, the single difference between the satellite 2 and the satellite 1 observes the pseudo-range residual error m _2,1 The method can be calculated by the following formula:

the terminal can respectively calculate single-difference observation pseudo-range residuals of n-1 pairs of satellites according to the above formula to form a single-difference observation pseudo-range residual sequence M= { M1, M2, … Mn-1}:

in one embodiment, calculating a second type of statistical parameter for the single-difference observed pseudorange residual based on the post-test observed pseudorange variance matrix and the single-difference observed pseudorange residual comprises: and calculating the square root and the absolute intermediate difference of the single-difference observation pseudo-range residual sequences according to the single-difference observation pseudo-range residual sequences formed by the single-difference observation pseudo-range residuals of the non-reference satellites.

The square root delta gamma of the single difference observation pseudo-range residual sequence is calculated as follows:

the calculation formula of the absolute intermediate bit difference delta tau of the single-difference observation pseudo-range residual sequence is as follows:

Δτ＝1.4826·Median({M ₁ -Median(M),M ₂ -Median(M),...,M _n-1 -Median(M)})；

in one embodiment, calculating a second type of statistical parameter for the single-difference observed pseudorange residual based on the post-test observed pseudorange variance matrix and the single-difference observed pseudorange residual comprises: calculating the post-observation pseudo-range variance of the satellite according to the signal-to-noise ratio of the observation pseudo-range, the altitude angle of the satellite determined based on the satellite position corresponding to the current epoch satellite and the terminal position obtained by resolving, and the error in the unit weight of the observation pseudo-range residual error in the first type of statistical parameters; constructing a post-test observed pseudo-range variance matrix according to the post-test observed pseudo-range variances of the satellites; and calculating the error in the unit weight of the single-difference observed pseudo-range residual sequence according to the tested observed pseudo-range variance matrix and the single-difference observed pseudo-range residual sequence.

The calculation formula of the post-test observation pseudo-range variance of the satellite is as follows:

wherein,CNO ⁱ signal-to-noise ratio, el, of the observed pseudorange for satellite i (i=1, 2, …, m) ⁱ The altitude of satellite i is determined based on the satellite position of satellite i and the terminal position.

The terminal constructs a post-test observed pseudo-range variance matrix S according to the post-test observed pseudo-range variances of the satellites:

/>

Calculating the error in the unit weight of the single-difference observed pseudo-range residual sequence according to the tested observed pseudo-range variance matrix S and the single-difference observed pseudo-range residual sequence M:

FIG. 10 is a flow chart illustrating the calculation of the second type of statistical information according to one embodiment. Referring to fig. 10, after obtaining a terminal positioning result through positioning calculation, calculating a checked observed pseudo-range variance matrix according to the terminal position and the error in the unit weight in the first type of statistical parameters; selecting a reference satellite, and constructing a single-difference observation pseudo-range residual sequence according to the single-difference observation pseudo-range residual of the satellite; and calculating a square mean root delta gamma and an absolute medium bit delta tau according to the single-difference observation pseudo-range residual sequence, and calculating an error delta in the unit weight according to the single-difference observation pseudo-range residual sequence and the checked observation pseudo-range variance matrix.

In one embodiment, the terminal may calculate a post-test parameter covariance matrix for the current epoch and a post-test parameter covariance matrix for the previous epoch; and calculating the relative variance of the posterior variance according to the posterior parameter covariance matrix of the adjacent epochs.

According to the previous explanation of the epoch, the satellite observation data corresponding to each epoch is different, the terminal positioning result calculated by each epoch is different, and the post-verification parameter covariance matrix of the current epoch can be recorded as P _j+1 The post-test parameter covariance matrix of the previous epoch can be denoted as P _j . The terminal can calculate the relative variance of the posterior variance according to the following formula

In one embodiment, calculating the post-test parameter covariance matrix for the current epoch includes: calculating the satellite observation pseudo-range variance according to the signal-to-noise ratio of the current epoch observation pseudo-range and the satellite altitude angle determined based on the satellite position corresponding to the current epoch satellite and the terminal position obtained by resolving; constructing an observed pseudo-range variance matrix according to the observed pseudo-range variances of the satellites; acquiring a differential matrix of a pseudo-range observation equation aiming at parameters to be estimated, wherein the parameters to be estimated comprise the position of a terminal to be estimated and the clock error of the terminal to be estimated; and calculating a post-test parameter covariance matrix of the current epoch according to the observed pseudo-range variance matrix, the differential matrix and the error in the unit weight of the current epoch about the observed pseudo-range residual.

/>

The observed pseudo-range variance matrix of the current epoch and the previous epoch is respectively marked as w _ρ (j+1)、w _ρ (j)。

The terminal constructs a pseudo-range observation equation of the current epoch according to satellite observation data of the current epoch, and acquires a differential matrix of the pseudo-range observation equation aiming at parameters to be estimated:

the terminal constructs a pseudo-range observation equation of the previous epoch according to satellite observation data of the previous epoch, and acquires a differential matrix of the pseudo-range observation equation aiming at parameters to be estimated:

post-test parameter covariance matrix P of current epoch _j+1 The calculation formula of (2) is as follows:

P _j+1 ＝δ _j+1 (G _ρ ^T (j+1)W(j+1)G _ρ (j+1) ^T )；

post-test parameter covariance matrix P of previous epoch _j The calculation formula of (2) is as follows:

P _j ＝δ _j (G _ρ ^T (j)W(j)G _ρ (j) ^T )。

in one embodiment, the terminal may count the relative variation of the error in the unit weight of the current epoch and the previous epoch with respect to the observed pseudo-range residual, the relative variation of Fang Jun root, and the relative variation of the absolute intermediate bit; counting the relative variation of errors in unit weights of the single-difference observation pseudo-range residual errors, the relative variation of Fang Jun roots and the relative variation of absolute middle bit differences of the current epoch and the previous epoch respectively; and evaluating the positioning quality of the positioning result of the current epoch terminal according to the relative variation between the first type of statistical parameters corresponding to the current epoch and the previous epoch and the relative variation between the second type of statistical parameters corresponding to the current epoch and the previous epoch.

The calculation of the relative change amount of the error in the unit weight of the current epoch and the previous epoch respectively about the observed pseudo-range residual error, the relative change amount of Fang Jun root and the relative change amount of the absolute intermediate potential difference are sequentially as follows:

the calculation of the relative change amount of errors in unit weights of the single-difference observation pseudo-range residual errors, the relative change amount of Fang Jun roots and the relative change amount of absolute middle bit differences of the current epoch and the previous epoch respectively are sequentially expressed as follows:

further, the terminal may further determine a maximum value among the posterior variance relative change amount, the relative change amount of the error in the unit weight with respect to the observed pseudo-range residual, the relative change amount of Fang Jun root and the relative change amount of the absolute intermediate bit, the relative change amount of the error in the unit weight with respect to the single-difference observed pseudo-range residual, the relative change amount of Fang Jun root and the relative change amount of the absolute intermediate bit; comparing the determined maximum value with a threshold value corresponding to each level of positioning track smoothness, and determining the positioning track smoothness corresponding to the current epoch; and evaluating the positioning quality of the positioning result of the current epoch terminal according to the smoothness of the positioning track.

Specifically, referring to fig. 11, a schematic diagram is shown for determining the smoothness of the current positioning track of the terminal in one embodiment. Referring to fig. 11, the terminal can output the unit weight error, square root, absolute median difference of the single epoch observed pseudo-range residual according to the terminal positioning result of single epoch least square solution, thereby obtaining the relative variation of the unit weight error, fang Jun root relative variation, absolute median difference relative variation of adjacent epochs with respect to the observed pseudo-range residual Based on the single-difference observation pseudo-range residual of each epoch, the relative variation of errors in unit weights of adjacent epochs about the single-difference observation pseudo-range residual, the relative variation of Fang Jun root and the relative variation of absolute intermediate bit difference can be countedThe terminal can be based on the above relative variation and the posterior variance relative variation +.>And judging the smoothness of the current positioning track of the terminal.

Assume thatAnd->If epsilon is greater than 1.5, determining that the smoothness of the positioning track of the current epoch terminal appears intolerant jump, namely that the positioning result may deviate greatly; when epsilon is larger than 1.0, determining that the smoothness of the positioning track of the current epoch terminal is expressed as a tolerance jump, namely the deviation of the positioning result is still acceptable; when epsilon is less than 1.0, determining the current epoch terminalThe smoothness of the bit track is represented as a smooth track, namely the positioning quality of the positioning result is good. That is, will->And->And comparing the current terminal positioning quality with a preset threshold value, and filtering a positioning result with poor position precision or obvious deviation.

Referring to fig. 12, a schematic diagram of a scenario in which a terminal is located is determined in one embodiment. Referring to FIG. 12, the terminal may also vary relative to the posterior varianceThe scene where the terminal is located is determined with respect to the error delta in the unit weight of the observed pseudo-range residual and the error delta in the unit weight of the single difference observed pseudo-range residual.

Specifically, when δ < 1 and Δδ < 1, the terminal is located in an open scene; when delta is more than 1 and less than 1.2 and delta is more than 1 and less than 1.2, the terminal is positioned in a semi-shielding scene; when delta is more than 1.2 and less than 1.5, and delta is more than 1.2 and less than 1.5, the terminal is positioned in the shielding scene; when delta is more than 1.5 and delta is more than 1.5, the terminal is positioned in a street scene of a high building; when (when)And when the terminal is in the tunnel entering and exiting scene. The discrimination of other terminal scenes can also be based on +.>And d, adapting the values of delta and delta.

In one embodiment, the terminal may further obtain, from the satellite observation data, a signal-to-noise ratio of an observation pseudo range corresponding to each satellite from which the satellite transmission signal is received by the terminal; and outputting statistical information about the signal-to-noise ratio according to the maximum value, the minimum value, the standard deviation and the absolute middle bit difference in the signal-to-noise ratio of the observed pseudo range of each satellite.

Specifically, the terminal receives signals transmitted by n satellites, and the signal to noise ratio of the terminal to obtain n satellite signals is t= { CN0 ₁ ,CN0 ₂ ,...,CN0 _n }；

Maximum and minimum values are CN0 _max ＝MAX(T)；CN0 _min (MIN(T)；

The standard deviation and variance are:

σ ² _CN0 ＝(σ _CN0 ) ² ；

the absolute medium potential difference is:

τ _CN0 ＝1.4826·Median({CN0 ₁ -Median(T),CN0 ₂ -Median(T),...,CN0 _n -Median(T)})。

it will be appreciated that the larger the signal to noise ratio value, the better the observed data quality. For example, the terminal may compare the maximum snr with a preset threshold value min, compare the minimum snr with a preset threshold value max, and if the maximum snr is smaller than the preset threshold value min, this indicates that the observed data quality is poor, otherwise if the minimum snr is greater than the preset threshold value max, this indicates that the observed data quality is excellent. If the comparison result is the comparison result, the judgment can be carried out according to the actual requirement. Decisions may also be made based on signal-to-noise variance and standard deviation. Therefore, the quality of the positioning result can be reflected to a certain extent based on the signal-to-noise ratio statistical information, and positioning quality assessment and quality control based on the signal-to-noise ratio statistical information are realized.

Based on the above, the terminal can output the statistics parameters related to the signal-to-noise ratio, the first type statistics parameters, the second type statistics parameters, the relative variation of the first type statistics parameters, the relative variation of the second type statistics parameters, the smoothness of the terminal positioning track, the scene of the terminal and other positioning quality evaluation indexes, one or more of the indexes can be used for accurately evaluating the positioning quality of the terminal, and the quality control is performed on the terminal output positioning result, so that the position evaluation accuracy of the terminal can be improved. The indexes can also be used for fusion positioning of the terminal by combining with the sensor to obtain a more accurate positioning result.

In a specific embodiment, the positioning quality evaluation method comprises the following steps:

1. acquiring satellite observation data of a current epoch of a terminal, wherein the satellite observation data comprises an observation pseudo range between the terminal and a satellite and a signal-to-noise ratio of the observation pseudo range;

2. calculating the transmitting time of satellite signals according to the observed pseudo range between the current epoch terminal and the satellite and the receiving time of the satellite signals received by the terminal, inquiring the satellite real-time navigation ephemeris according to the transmitting time, and obtaining the satellite position and the satellite clock error corresponding to the current epoch satellite;

3. constructing a pseudo-range observation equation between the terminal and the satellite according to the observed pseudo-range, the terminal position to be estimated, the terminal clock error to be estimated, the satellite position and the satellite clock error; carrying out least square calculation on the pseudo-range observation equation based on satellite observation data to obtain a terminal positioning result, wherein the terminal positioning result comprises a terminal position and a terminal clock error;

4. determining a positioning distance between a satellite and a terminal according to the terminal position, the terminal clock error, the satellite position and the satellite clock error, and determining a single difference observation pseudo-range residual sequence according to the difference between an observation pseudo-range of the satellite and the positioning distance; calculating the square average root and absolute intermediate difference of an observed pseudo-range residual sequence;

5. Calculating the variance of the observed pseudo range of the satellite according to the signal-to-noise ratio of the observed pseudo range and the altitude angle of the satellite determined based on the satellite position corresponding to the current epoch satellite and the terminal position obtained by resolving; constructing an observed pseudo-range variance matrix according to the observed pseudo-range variances of the satellites; calculating an error in a unit weight related to the observed pseudo-range residual sequence according to the observed pseudo-range residual sequence and the observed pseudo-range variance matrix;

6. determining a reference satellite from the observation satellites of the current epoch terminal; for each non-reference satellite in the observation satellites, calculating an observation single difference between the observation pseudo range of the non-reference satellite and the observation pseudo range of the reference satellite, and calculating a positioning single difference between a positioning distance corresponding to the non-reference satellite and a positioning distance corresponding to the reference satellite;

7. determining a single-difference observation pseudo-range residual sequence according to residual errors between the observation single differences and the positioning single differences corresponding to the non-reference satellites; calculating square average root and absolute middle bit difference of a single-difference observation pseudo-range residual sequence;

8. calculating the post-observation pseudo-range variance of the satellite according to the signal-to-noise ratio of the observation pseudo-range, the altitude angle of the satellite determined based on the satellite position corresponding to the current epoch satellite and the terminal position obtained by resolving, and the error in the unit weight of the observation pseudo-range residual error in the first type of statistical parameters; constructing a post-test observed pseudo-range variance matrix according to the post-test observed pseudo-range variances of the satellites; calculating an error in a unit weight of the single-difference observed pseudo-range residual sequence according to the tested observed pseudo-range variance matrix and the single-difference observed pseudo-range residual sequence;

9. Acquiring a differential matrix of a pseudo-range observation equation aiming at parameters to be estimated, wherein the parameters to be estimated comprise the position of a terminal to be estimated and the clock error of the terminal to be estimated; calculating a post-verification parameter covariance matrix of the current epoch according to the observed pseudo-range variance matrix and the differential matrix in the step 5 and the error in the unit weight of the current epoch about the observed pseudo-range residual error; calculating the relative variance of the posterior variance according to the posterior parameter covariance matrix of the current epoch and the posterior parameter covariance matrix of the previous epoch;

10. counting the relative variation of errors in unit weights of the current epoch and the previous epoch respectively about the observed pseudo-range residual error, the relative variation of Fang Jun roots and the relative variation of absolute intermediate bit difference; counting the relative variation of errors in unit weights of the single-difference observation pseudo-range residual errors, the relative variation of Fang Jun roots and the relative variation of absolute middle bit differences of the current epoch and the previous epoch respectively;

11. determining the maximum of the posterior variance relative change, the relative change of the error in the unit weight with respect to the observed pseudo-range residual, the relative change of Fang Jun root and the relative change of the absolute median difference, the relative change of the error in the unit weight with respect to the single-difference observed pseudo-range residual, the relative change of Fang Jun root and the relative change of the absolute median difference; comparing the determined maximum value with a threshold value corresponding to each level of positioning track smoothness, and determining the positioning track smoothness corresponding to the current epoch;

12. Determining a scene where the terminal is located according to the relative variance after test, the error in the unit weight related to the observed pseudo-range residual and the error in the unit weight related to the single-difference observed pseudo-range residual;

13. acquiring signal-to-noise ratios of observation pseudo ranges corresponding to all satellites of satellite transmitting signals received by a terminal from satellite observation data; outputting statistical information about the signal-to-noise ratio according to the maximum value, the minimum value, the standard deviation and the absolute intermediate bit difference in the signal-to-noise ratio of the observed pseudo range of each satellite;

14. according to the square root, absolute medium bit difference and unit weight error of the observed pseudo-range residual sequence; square root, absolute middle bit difference and unit weight middle error of single-difference observation pseudo-range residual error sequence; and the relative variance of the post-test variances of adjacent epochs, the relative variance of unit weight errors, square root and absolute middle bit differences between the current epoch and the previous epoch about the observed pseudo-range residual errors; and the relative variation of unit weight error, square root and absolute intermediate bit difference of single-difference observation pseudo-range residual error between the current epoch and the previous epoch; and one or more of the smoothness of the positioning track corresponding to the current epoch, the scene in which the terminal is positioned and the statistical information of the signal to noise ratio, and evaluating the positioning quality of the positioning result of the terminal.

According to the positioning quality evaluation method, satellite observation data of the current epoch of the terminal are obtained, so that a pseudo-range observation equation between the terminal and the satellite is constructed based on the observation pseudo-range in the satellite observation data, the pseudo-range observation equation is further solved based on the satellite observation data, an observation pseudo-range residual error can be determined according to a terminal positioning result obtained through solving, and first-class statistical parameters related to the observation pseudo-range residual error are calculated; in addition, the single-difference observation pseudo-range residual error is determined through the observation pseudo-range of the satellite and the terminal positioning result obtained through the calculation, and further, second-class statistical parameters related to the single-difference observation pseudo-range residual error can be calculated based on the tested observation pseudo-range variance matrix and the single-difference observation pseudo-range residual error, so that the relative variation between the first-class statistical parameters corresponding to each current epoch and the previous epoch and the relative variation between the second-class statistical parameters corresponding to each previous epoch are combined, the relative variation is used as a positioning quality evaluation index, the positioning quality of the terminal positioning result of the current epoch can be accurately evaluated, and the accuracy of the terminal positioning result is improved.

It should be understood that, although the steps in the flowcharts related to the above embodiments are sequentially shown as indicated by arrows, these steps are not necessarily sequentially performed in the order indicated by the arrows. The steps are not strictly limited to the order of execution unless explicitly recited herein, and the steps may be executed in other orders. Moreover, at least some of the steps in the flowcharts described in the above embodiments may include a plurality of steps or a plurality of stages, which are not necessarily performed at the same time, but may be performed at different times, and the order of the steps or stages is not necessarily performed sequentially, but may be performed alternately or alternately with at least some of the other steps or stages.

Based on the same inventive concept, the embodiment of the application also provides a positioning quality evaluation device for realizing the positioning quality evaluation method. The implementation of the solution provided by the device is similar to the implementation described in the above method, so the specific limitation in one or more embodiments of the positioning quality evaluation device provided below may refer to the limitation of the positioning quality evaluation method hereinabove, and will not be repeated herein.

In one embodiment, as shown in fig. 13, there is provided a positioning quality evaluation apparatus 1300 comprising: an acquisition module 1302, a first statistics module 1304, a second statistics module 1306, and a quality assessment module 1308, wherein:

an acquisition module 1302, configured to acquire satellite observation data of a current epoch of a terminal, where the satellite observation data includes an observed pseudo-range between the terminal and a satellite; acquiring a terminal positioning result obtained by resolving according to the satellite observation data;

a first statistics module 1304, configured to determine an observed pseudo-range residual of a satellite according to an observed pseudo-range of the satellite and the terminal positioning result, and calculate a first type of statistical parameter related to the observed pseudo-range residual;

A second statistics module 1306, configured to determine single-difference observed pseudo-range residuals between satellites according to observed pseudo-ranges of satellites and the terminal positioning result, and calculate second-class statistics parameters related to the single-difference observed pseudo-range residuals;

a quality evaluation module 1308, configured to evaluate, according to the first type statistics and the second type statistics, positioning quality of the terminal positioning result in the current epoch.

In one embodiment, the apparatus further comprises: the pseudo-range observation equation construction module is used for calculating the transmitting time of the satellite signals according to the observation pseudo-range between the current epoch terminal and the satellite and the receiving time of the satellite signals received by the terminal; inquiring satellite real-time navigation ephemeris according to the transmitting time to obtain satellite positions and satellite clock errors corresponding to the current epoch satellites; constructing a pseudo-range observation equation between the terminal and the satellite according to the observed pseudo-range of each satellite, the satellite position and the satellite clock error, the position of the terminal to be estimated and the clock error of the terminal to be estimated; and solving the pseudo-range observation equation according to the satellite observation data to obtain a terminal positioning result.

In one embodiment, the first statistics module 1304 includes a positioning calculation unit, configured to calculate, in a multiple iteration process of performing least square calculation on the pseudo-range observation equation based on satellite observation data, an estimated distance between the terminal and the satellite according to a satellite position corresponding to the current epoch satellite, a satellite clock difference, a terminal position estimated value obtained in a previous iteration, and a terminal clock difference estimated value; residual errors between the observed pseudo-ranges and the estimated distances of all satellites are calculated, coarse difference elimination is carried out on the residual errors based on quartiles, target observed pseudo-ranges are screened out from the observed pseudo-ranges of all satellites, and the least square solution of the current iteration is carried out by using a pseudo-range observation equation formed by the target observed pseudo-ranges.

In one embodiment, the satellite observation data further includes a signal-to-noise ratio of the observation pseudo-range, and the first statistics module 1304 includes a positioning calculation unit, configured to obtain, in a current iteration process of least squares calculation, an estimated parameter of a previous iteration, where the estimated parameter includes an estimated position and an estimated clock difference; acquiring a target satellite screened after the previous iteration; calculating the variance of the observed pseudo range of the target satellite according to the signal-to-noise ratio of the observed pseudo range of the target satellite and the altitude angle of the satellite determined based on the satellite position corresponding to the target satellite and the terminal estimated position of the previous iteration; constructing an observed pseudo-range variance matrix according to the observed pseudo-range variances of all target satellites; determining a pseudo-range observation equation of the current iteration based on satellite observation data of the target satellite; acquiring a differential matrix of a pseudo-range observation equation of the current iteration aiming at parameters to be estimated, wherein the parameters to be estimated comprise the position of a terminal to be estimated and the clock error of the terminal to be estimated; determining an estimated parameter correction quantity of the current iteration according to the differential matrix, the observed pseudo-range variance matrix and the pseudo-range observation residual error of the target satellite of the current iteration; and correcting the estimated parameters of the previous iteration according to the estimated parameter correction quantity of the current iteration to obtain the estimated parameters of the current iteration.

In one embodiment, the positioning calculation unit is further configured to continue the iterative process when the estimated parameter correction amount of the next iteration is greater than a first preset threshold; when the correction quantity of the estimated parameters of the current iteration is smaller than a first preset threshold value, determining a post-test observation pseudo-range residual sequence and a post-test observation pseudo-range variance matrix of the current iteration based on the estimated parameters of the current iteration, and calculating chi-square test statistics according to the post-test observation pseudo-range variance matrix and the post-test observation pseudo-range residual sequence; when the chi-square test statistic is smaller than a second preset threshold, stopping iteration, and obtaining a positioning result of the terminal according to the estimation parameter of the current iteration; and when the chi-square test statistic is larger than a second preset threshold, carrying out normal distribution test on the post-test observation pseudo-range residual sequence based on the post-test observation pseudo-range residual covariance matrix of the current iteration, and after eliminating the observation pseudo-range which does not pass the normal distribution test, continuing the iteration process by utilizing the screened observation pseudo-range of the target satellite.

In one embodiment, the first statistics module 1304 includes a residual parameter statistics unit, configured to calculate a positioning distance between the terminal and the satellite according to a satellite position and a satellite clock difference corresponding to the current epoch satellite, and the calculated terminal position and the calculated terminal clock difference; calculating residual errors between the observed pseudo-ranges of all satellites and the corresponding positioning distances to obtain an observed pseudo-range residual error sequence; and calculating the square root and the absolute intermediate bit difference of the observed pseudo-range residual sequence.

In one embodiment, the residual parameter statistics unit is further configured to calculate an observed pseudo-range variance of the satellite according to a signal-to-noise ratio of the observed pseudo-range and an altitude angle of the satellite determined based on a satellite position corresponding to the current epoch satellite and the resolved terminal position; constructing an observed pseudo-range variance matrix according to the observed pseudo-range variances of the satellites; calculating an error in a unit weight related to the observed pseudo-range residual sequence according to the observed pseudo-range residual sequence and the observed pseudo-range variance matrix; and outputting the sequence of the observed pseudo-range residuals, and unit weight center error, square root and absolute center bit difference of the observed pseudo-range residuals.

In one embodiment, the second statistics module 1306 includes a single difference residual construction unit for determining a reference satellite from the observed satellites of the current epoch terminal; for each non-reference satellite in the observation satellites, calculating an observation single difference between the observation pseudo range of the non-reference satellite and the observation pseudo range of the reference satellite, and calculating a positioning single difference between a positioning distance corresponding to the non-reference satellite and a positioning distance corresponding to the reference satellite; and determining a single-difference observation pseudo-range residual sequence according to the residual between the observation single difference and the positioning single difference corresponding to each non-reference satellite.

In one embodiment, the second statistics module 1306 includes a single-difference residual parameter statistics unit, configured to calculate, according to a single-difference observed pseudo-range residual sequence formed by single-difference observed pseudo-range residuals of each non-reference satellite, a square root and an absolute medium bit difference of the single-difference observed pseudo-range residual sequence; calculating the post-observation pseudo-range variance of the satellite according to the signal-to-noise ratio of the observation pseudo-range, the altitude angle of the satellite determined based on the satellite position corresponding to the current epoch satellite and the terminal position obtained by resolving, and the error in the unit weight of the observation pseudo-range residual error in the first type of statistical parameters; constructing a post-test observed pseudo-range variance matrix according to the post-test observed pseudo-range variances of the satellites; calculating an error in a unit weight of the single-difference observed pseudo-range residual sequence according to the tested observed pseudo-range variance matrix and the single-difference observed pseudo-range residual sequence; and outputting the unit weight middle error, square root and absolute middle bit difference of the single difference observation pseudo-range residual.

In one embodiment, the first type of statistical parameter comprises a unit weight error with respect to an observed pseudorange residual; the terminal scene judging module is also used for calculating the satellite observation pseudo-range variance according to the signal-to-noise ratio of the current epoch observation pseudo-range and the satellite altitude determined based on the satellite position corresponding to the current epoch satellite and the terminal position obtained by resolving; constructing an observed pseudo-range variance matrix according to the observed pseudo-range variances of the satellites; acquiring a differential matrix of a pseudo-range observation equation aiming at parameters to be estimated, wherein the parameters to be estimated comprise the position of a terminal to be estimated and the clock error of the terminal to be estimated; and calculating a post-test parameter covariance matrix of the current epoch according to the observed pseudo-range variance matrix, the differential matrix and the error in the unit weight of the current epoch about the observed pseudo-range residual.

In one embodiment, the first type of statistical parameter includes a unit weight error, a root of square, and an absolute median difference with respect to an observed pseudorange residual; the second type of statistical parameters comprise unit weight middle error, square root and absolute middle bit difference of single difference observation pseudo-range residual errors;

the quality evaluation module is also used for counting the relative variation of errors in unit weights of the current epoch and the previous epoch respectively about the observed pseudo-range residual error, the relative variation of Fang Jun roots and the relative variation of absolute intermediate level difference; counting the relative variation of errors in unit weights of the single-difference observation pseudo-range residual errors, the relative variation of Fang Jun roots and the relative variation of absolute middle bit differences of the current epoch and the previous epoch respectively; and evaluating the positioning quality of the terminal positioning result of the current epoch according to the relative variation between the first type of statistical parameters corresponding to the current epoch and the previous epoch and the relative variation between the second type of statistical parameters corresponding to the current epoch.

In one embodiment, the quality assessment module 1308 is further configured to determine a maximum of a post-test variance relative change, a relative change in error in unit weight with respect to an observed pseudorange residual, a relative change in Fang Jun root and a relative change in absolute median, a relative change in error in unit weight with respect to a single difference observed pseudorange residual, a relative change in Fang Jun root and a relative change in absolute median; comparing the determined maximum value with a threshold value corresponding to each level of positioning track smoothness, and determining the positioning track smoothness corresponding to the current epoch; and evaluating the positioning quality of the positioning result of the current epoch terminal according to the smoothness of the positioning track.

In one embodiment, the satellite observation data further includes a signal-to-noise ratio of the observed pseudoranges, and the positioning quality assessment apparatus 1300 further includes: the signal-to-noise ratio information statistics module is used for acquiring the signal-to-noise ratio of the observation pseudo range corresponding to each satellite of the satellite transmission signals received by the terminal from the satellite observation data; outputting statistical information about the signal-to-noise ratio according to the maximum value, the minimum value, the standard deviation and the absolute intermediate bit difference in the signal-to-noise ratio of the observed pseudo range of each satellite;

the quality evaluation module 1308 is further configured to evaluate the positioning quality of the positioning result of the current epoch terminal according to the statistical information about the signal-to-noise ratio.

The positioning quality evaluation device 1300 obtains a terminal positioning result by obtaining satellite observation data of a current epoch of a terminal and calculating the satellite observation data based on the observation pseudo range in the satellite observation data, and further can determine an observation pseudo range residual according to the satellite observation pseudo range and the terminal positioning result, and calculate a first type of statistical parameter related to the observation pseudo range residual; in addition, the single-difference observation pseudo-range residual error is determined through the observation pseudo-range of the satellite and the terminal positioning result obtained through the calculation, and further the second type of statistical parameters related to the single-difference observation pseudo-range residual error can be calculated, so that the first type of statistical parameters and the second type of statistical parameters are combined to serve as positioning quality evaluation indexes, the positioning quality of the terminal positioning result of the current epoch can be accurately evaluated, and the accuracy of the terminal positioning result is improved.

The above-described respective modules in the positioning quality evaluation apparatus may be implemented in whole or in part by software, hardware, or a combination thereof. The above modules may be embedded in hardware or may be independent of a processor in the computer device, or may be stored in software in a memory in the computer device, so that the processor may call and execute operations corresponding to the above modules.

In one embodiment, a computer device is provided, which may be a terminal, and the internal structure thereof may be as shown in fig. 14. The computer device includes a processor, a memory, an input/output interface, a communication interface, a display unit, and an input means. The processor, the memory and the input/output interface are connected through a system bus, and the communication interface, the display unit and the input device are connected to the system bus through the input/output interface. Wherein the processor of the computer device is configured to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage media. The input/output interface of the computer device is used to exchange information between the processor and the external device. The communication interface of the computer device is used for carrying out wired or wireless communication with an external terminal, and the wireless mode can be realized through WIFI, a mobile cellular network, NFC (near field communication) or other technologies. The computer program is executed by a processor to implement a positioning quality assessment method. The display unit of the computer equipment is used for forming a visual picture, and can be a display screen, a projection device or a virtual reality imaging device, wherein the display screen can be a liquid crystal display screen or an electronic ink display screen, the input device of the computer equipment can be a touch layer covered on the display screen, can also be a key, a track ball or a touch pad arranged on a shell of the computer equipment, and can also be an external keyboard, a touch pad or a mouse and the like.

It will be appreciated by those skilled in the art that the structure shown in fig. 14 is merely a block diagram of a portion of the structure associated with the present inventive arrangements and is not limiting of the computer device to which the present inventive arrangements are applied, and that a particular computer device may include more or fewer components than shown, or may combine certain components, or have a different arrangement of components.

In one embodiment, a computer device is provided, comprising a memory and a processor, the memory having stored therein a computer program, the processor implementing the steps of the positioning quality assessment method provided by any one or more of the embodiments described above when the computer program is executed.

In one embodiment, a computer readable storage medium is provided, on which a computer program is stored which, when executed by a processor, implements the steps of the positioning quality assessment method provided by any one or more of the embodiments described above.

In one embodiment, a computer program product is provided comprising a computer program which, when executed by a processor, implements the steps of the positioning quality assessment method provided by any one or more of the embodiments described above. It should be noted that, the user information (including but not limited to user equipment information, user personal information, etc.) and the data (including but not limited to data for analysis, stored data, presented data, etc.) related to the present application are information and data authorized by the user or sufficiently authorized by each party, and the collection, use and processing of the related data need to comply with the related laws and regulations and standards of the related country and region.

Those skilled in the art will appreciate that implementing all or part of the above described methods may be accomplished by way of a computer program stored on a non-transitory computer readable storage medium, which when executed, may comprise the steps of the embodiments of the methods described above. Any reference to memory, database, or other medium used in embodiments provided herein may include at least one of non-volatile and volatile memory. The nonvolatile Memory may include Read-Only Memory (ROM), magnetic tape, floppy disk, flash Memory, optical Memory, high density embedded nonvolatile Memory, resistive random access Memory (ReRAM), magnetic random access Memory (Magnetoresistive Random Access Memory, MRAM), ferroelectric Memory (Ferroelectric Random Access Memory, FRAM), phase change Memory (Phase Change Memory, PCM), graphene Memory, and the like. Volatile memory can include random access memory (Random Access Memory, RAM) or external cache memory, and the like. By way of illustration, and not limitation, RAM can be in the form of a variety of forms, such as static random access memory (Static Random Access Memory, SRAM) or dynamic random access memory (Dynamic Random Access Memory, DRAM), and the like. The databases referred to in the embodiments provided herein may include at least one of a relational database and a non-relational database. The non-relational database may include, but is not limited to, a blockchain-based distributed database, and the like. The processor referred to in the embodiments provided in the present application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic unit, a data processing logic unit based on quantum computing, or the like, but is not limited thereto.

The technical features of the above embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.

The foregoing examples illustrate only a few embodiments of the application and are described in detail herein without thereby limiting the scope of the application. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the application, which are all within the scope of the application. Accordingly, the scope of the application should be assessed as that of the appended claims.

Claims

1. A method of positioning quality assessment, the method comprising:

acquiring satellite observation data of a current epoch of a terminal, wherein the satellite observation data comprises an observation pseudo range between the terminal and a satellite; acquiring a terminal positioning result obtained by resolving according to the satellite observation data;

2. The method of claim 1, wherein the obtaining the terminal positioning result obtained by performing the calculation according to the satellite observation data comprises:

calculating the transmitting time of the satellite signals according to the observed pseudo range between the current epoch terminal and the satellite and the receiving time of the satellite signals received by the terminal;

inquiring satellite real-time navigation ephemeris according to the transmitting time to obtain a satellite position and a satellite clock error corresponding to the current epoch satellite;

constructing a pseudo-range observation equation between the terminal and the satellite according to the observed pseudo-range of each satellite, the satellite position and the satellite clock error, the position of the terminal to be estimated and the clock error of the terminal to be estimated;

and solving the pseudo-range observation equation according to the satellite observation data to obtain a terminal positioning result.

3. The method according to claim 2, wherein the method further comprises:

In a multiple iteration process of carrying out least square calculation on the pseudo-range observation equation based on the satellite observation data, calculating the estimated distance between the terminal and the satellite according to the satellite position corresponding to the current epoch satellite, the satellite clock difference, the terminal position estimated value obtained in the previous iteration and the terminal clock difference estimated value;

calculating residual errors between the observed pseudo-ranges and the estimated distances of all satellites, performing coarse difference elimination on the residual errors based on quartiles, screening target observed pseudo-ranges from the observed pseudo-ranges of all satellites, and performing least square solution of current iteration by using a pseudo-range observation equation formed by the target observed pseudo-ranges.

4. The method of claim 2, wherein the satellite observation data further comprises a signal-to-noise ratio of the observed pseudorange, the method further comprising:

in the current iteration process of least square solution, obtaining estimation parameters of the previous iteration, wherein the estimation parameters comprise an estimation position and an estimation clock difference; acquiring a target satellite screened after the previous iteration;

calculating the variance of the observed pseudo range of the target satellite according to the signal-to-noise ratio of the observed pseudo range of the target satellite and the altitude angle of the satellite determined based on the satellite position corresponding to the target satellite and the terminal estimated position of the previous iteration; constructing an observed pseudo-range variance matrix according to the observed pseudo-range variances of all target satellites;

Determining a pseudo-range observation equation of the current iteration based on satellite observation data of the target satellite;

acquiring a differential matrix of a pseudo-range observation equation of the current iteration aiming at parameters to be estimated, wherein the parameters to be estimated comprise the position of a terminal to be estimated and the clock error of the terminal to be estimated; determining an estimated parameter correction of the current iteration according to the differential matrix, the observed pseudo-range variance matrix and the pseudo-range observation residual error of the target satellite of the current iteration;

and correcting the estimated parameters of the previous iteration according to the estimated parameter correction quantity of the current iteration to obtain the estimated parameters of the current iteration.

5. The method according to claim 4, wherein the method further comprises:

when the correction quantity of the estimated parameters of the current iteration is larger than a first preset threshold value, continuing the iteration process;

when the correction amount of the estimated parameters of the current iteration is smaller than a first preset threshold value, determining a post-test observation pseudo-range residual sequence and a post-test observation pseudo-range variance matrix of the current iteration based on the estimated parameters of the current iteration, and calculating chi-square test statistics according to the post-test observation pseudo-range variance matrix and the post-test observation pseudo-range residual sequence;

When the chi-square test statistic is smaller than a second preset threshold, stopping iteration, and obtaining a positioning result of the terminal according to the estimation parameter of the current iteration;

and when the chi-square test statistic is larger than a second preset threshold, carrying out normal distribution test on the post-test observation pseudo-range residual sequence based on the post-test observation pseudo-range residual covariance matrix of the current iteration, and continuing the iteration process by using the screened observation pseudo-range of the target satellite after eliminating the observation pseudo-range which does not pass the normal distribution test.

6. The method of claim 1, wherein determining an observed pseudorange residual for a satellite based on the observed pseudorange for the satellite and the terminal location result, calculating a first type of statistical parameter for the observed pseudorange residual, comprises:

calculating the positioning distance between the terminal and the satellite according to the satellite position and the satellite clock error corresponding to the current epoch satellite, and the terminal position and the terminal clock error obtained by calculation;

calculating residual errors between the observed pseudo-ranges of all satellites and the corresponding positioning distances to obtain an observed pseudo-range residual error sequence;

and calculating the square root and the absolute intermediate bit difference of the observed pseudo-range residual sequence.

7. The method of claim 6, wherein the satellite observation data further comprises a signal-to-noise ratio of the observed pseudorange, the method further comprising:

Calculating the variance of the observed pseudo range of the satellite according to the signal-to-noise ratio of the observed pseudo range and the altitude angle of the satellite determined based on the satellite position corresponding to the current epoch satellite and the terminal position obtained by resolving; constructing an observed pseudo-range variance matrix according to the observed pseudo-range variances of the satellites;

calculating an error in unit weight of the observed pseudo-range residual sequence according to the observed pseudo-range residual sequence and the observed pseudo-range variance matrix;

and outputting the sequence of the observed pseudo-range residuals, and unit weight center error, square root and absolute center difference of the observed pseudo-range residuals.

8. The method of claim 1, wherein determining a single-difference observed pseudorange residual between satellites based on the observed pseudoranges of satellites and the terminal positioning result comprises:

determining a reference satellite from the observed satellites of the terminal in the current epoch;

for each non-reference satellite in the observation satellites, calculating an observation single difference between the observation pseudo range of the non-reference satellite and the observation pseudo range of the reference satellite, and calculating a positioning single difference between the positioning distance corresponding to the non-reference satellite and the positioning distance corresponding to the reference satellite;

And determining a single-difference observation pseudo-range residual sequence according to the residual between the observation single difference corresponding to each non-reference satellite and the positioning single difference.

9. The method of claim 8, wherein said calculating a second type of statistical parameter for said single difference observed pseudorange residuals comprises:

calculating square root and absolute middle bit difference of a single-difference observation pseudo-range residual sequence formed by single-difference observation pseudo-range residual of each non-reference satellite;

calculating a post-observation pseudo-range variance of the satellite according to the signal-to-noise ratio of the observation pseudo-range, the altitude angle of the satellite determined based on the satellite position corresponding to the current epoch satellite and the terminal position obtained by resolving, and the error in the unit weight of the first type of statistical parameters about the observation pseudo-range residual; constructing a post-test observed pseudo-range variance matrix according to the post-test observed pseudo-range variances of the satellites; calculating an error in a unit weight of the single-difference observation pseudo-range residual sequence according to the checked observation pseudo-range variance matrix and the single-difference observation pseudo-range residual sequence;

and outputting a unit weight middle error, a square root and an absolute middle bit difference of the single-difference observed pseudo-range residual.

10. The method of claim 1, wherein the first type of statistical parameter comprises a unit weight error with respect to an observed pseudorange residual; the second class of statistical parameters includes errors in unit weights for the single difference observed pseudorange residuals; the method further comprises the steps of:

determining a scene where the terminal is located according to the error in the unit weight of the observed pseudo-range residual error and the error in the unit weight of the single-difference observed pseudo-range residual error;

and evaluating the positioning quality of the terminal positioning result in the current epoch according to the scene of the terminal.

11. The method of claim 10, wherein the determining the scene in which the terminal is located based on the error in the unit weight for the observed pseudorange residual and the error in the unit weight for the single difference observed pseudorange residual comprises:

calculating a post-test parameter covariance matrix of the current epoch and a post-test parameter covariance matrix of the previous epoch;

calculating the relative variance of the posterior variance according to the posterior parameter covariance matrix of the adjacent calendar elements;

and determining the scene where the terminal is located according to the relative variance after test, the error in the unit weight related to the observed pseudo-range residual and the error in the unit weight related to the single-difference observed pseudo-range residual.

12. The method of claim 11, wherein the first type of statistical parameter comprises a unit weight error with respect to an observed pseudorange residual; the calculating the post-test parameter covariance matrix of the current epoch comprises the following steps:

calculating the variance of the observed pseudo range of the satellite according to the signal-to-noise ratio of the observed pseudo range of the current epoch and the altitude angle of the satellite determined based on the satellite position corresponding to the current epoch satellite and the terminal position obtained by resolving; constructing an observed pseudo-range variance matrix according to the observed pseudo-range variances of the satellites;

acquiring a differential matrix of the pseudo-range observation equation for parameters to be estimated, wherein the parameters to be estimated comprise the position of a terminal to be estimated and the clock error of the terminal to be estimated;

and calculating a post-test parameter covariance matrix of the current epoch according to the observed pseudo-range variance matrix, the differential matrix and the error in the unit weight of the current epoch relative to the observed pseudo-range residual.

13. The method of claim 1, wherein the first type of statistical parameter comprises a unit weight error, a square root, and an absolute median bit error with respect to an observed pseudorange residual; the second type of statistical parameters comprise unit weight middle error, square mean root and absolute middle difference of the single difference observation pseudo-range residual error;

The step of evaluating the positioning quality of the terminal positioning result in the current epoch according to the first type of statistical parameters and the second type of statistical parameters comprises the following steps:

counting the relative variation of errors in unit weights of the current epoch and the previous epoch respectively about the observed pseudo-range residual error, the relative variation of Fang Jun roots and the relative variation of absolute intermediate bit difference;

counting the relative variation of errors in unit weights of the current epoch and the previous epoch respectively about the single-difference observation pseudo-range residual error, the relative variation of Fang Jun roots and the relative variation of absolute intermediate bit difference;

and evaluating the positioning quality of the terminal positioning result of the current epoch according to the relative variation between the first type of statistical parameters corresponding to the current epoch and the previous epoch and the relative variation between the second type of statistical parameters corresponding to the current epoch.

14. The method according to claim 13, wherein the evaluating the positioning quality of the terminal positioning result of the current epoch according to the relative variation between the first type of statistical parameter corresponding to each of the current epoch and the previous epoch and the relative variation between the second type of statistical parameter corresponding to each of the current epoch includes:

Determining the maximum of the posterior variance relative change, the relative change in error in unit weight with respect to the observed pseudorange residual, the relative change in Fang Jun and the relative change in absolute median, the relative change in error in unit weight with respect to the single difference observed pseudorange residual, the relative change in Fang Jun and the relative change in absolute median;

comparing the determined maximum value with a threshold value corresponding to each level of positioning track smoothness, and determining the positioning track smoothness corresponding to the current epoch;

and evaluating the positioning quality of the terminal positioning result of the current epoch according to the smoothness of the positioning track.

15. The method of any one of claims 1 to 14, wherein the satellite observation data further comprises a signal-to-noise ratio of the observed pseudorange, the method further comprising:

acquiring signal-to-noise ratios of observation pseudo ranges corresponding to all satellites of satellite transmitting signals received by a terminal from the satellite observation data;

outputting statistical information about the signal-to-noise ratio according to the maximum value, the minimum value, the standard deviation and the absolute middle bit difference in the signal-to-noise ratio of the observed pseudo range of each satellite;

and according to the statistical information about the signal-to-noise ratio, evaluating the positioning quality of the terminal positioning result in the current epoch.

16. A positioning quality evaluation device, characterized in that the device comprises:

17. A computer device comprising a memory and a processor, the memory storing a computer program, characterized in that the processor implements the steps of the method of any one of claims 1 to 15 when the computer program is executed.

18. A computer readable storage medium, on which a computer program is stored, characterized in that the computer program, when being executed by a processor, implements the steps of the method of any of claims 1 to 15.

19. A computer program product comprising a computer program, characterized in that the computer program, when being executed by a processor, implements the steps of the method of any one of claims 1 to 15.