WO2024152673A1

WO2024152673A1 - Mobile terminal positioning method and apparatus, and device and storage medium

Info

Publication number: WO2024152673A1
Application number: PCT/CN2023/129378
Authority: WO
Inventors: 周启帆; 卞光宇; 童梦想; 袁义龙
Original assignee: 腾讯科技（深圳）有限公司
Priority date: 2023-01-18
Filing date: 2023-11-02
Publication date: 2024-07-25
Also published as: CN116953747A

Abstract

A mobile terminal (101) positioning method, which is executed by a computer device (1400). The mobile terminal (101) positioning method comprises: acquiring a preliminarily positioned location of a mobile terminal (101), and determining building data of at least one building around the preliminarily positioned location, and satellite location data of a satellite around the preliminarily positioned location (210); for an i-th grid unit (104) among M grid units (104) located around the preliminarily positioned location, and according to the building data and the satellite location data, determining measured line-of-sight information corresponding to the i-th grid unit (104), M being an integer greater than 1, and i being an integer smaller than or equal to M (220); according to the measured line-of-sight information corresponding to the i-th grid unit (104) and satellite signal measurement information corresponding to the i-th grid unit (104), determining a comprehensive score corresponding to the i-th grid unit (104) (230); and according to comprehensive scores respectively corresponding to the M grid units (104), determining a positioning result (240) of the mobile terminal (101).

Description

Mobile terminal positioning method, device, equipment and storage medium

Related Applications

This application claims priority to Chinese patent application number 2023101191645, filed on January 18, 2023, entitled “POSITIONING METHOD, APPARATUS, DEVICE AND STORAGE MEDIUM FOR MOBILE TERMINAL”, the entire text of which is hereby incorporated by reference.

Technical Field

The present application relates to the field of positioning technology, and in particular to a positioning method, device, equipment and storage medium for a mobile terminal.

Background technique

The Global Navigation Satellite System (GNSS) is an airborne radio navigation and positioning system that can provide users with all-weather 3D coordinates, speed and time information anywhere on the Earth's surface or in near-Earth space. The GNSS can be used to locate vehicles, mobile phones and other mobile devices, and can also locate children or the elderly so that their exact location can be determined in time when they are lost.

Related technologies include methods for using virtual elevation models to assist satellite navigation positioning in urban environments. Using the elevation information in the 3D (3D) model of the city, according to the different characteristics of elevation changes in the urban environment, corresponding virtual elevation observations are constructed, and the constructed virtual elevation observations are integrated with the original observations from the satellite navigation receiver, and finally the final solution of the user's position is obtained through the weighted least squares algorithm.

However, the above method only uses the elevation information of the city 3D model, which easily leads to poor positioning accuracy.

Summary of the invention

Embodiments of the present application provide a method, apparatus, device, and storage medium for positioning a mobile terminal.

According to one aspect of an embodiment of the present application, a positioning method for a mobile terminal is provided, which is executed by a computer device, and the method includes:

Acquire a preliminary positioning position of the mobile terminal, determine building data of at least one building around the preliminary positioning position, and satellite position data of satellites around the preliminary positioning position;

For an i-th grid cell among M grid cells located around the preliminary positioning position, determining, according to the building data and the satellite position data, the measured line-of-sight information corresponding to the i-th grid cell, where M is an integer greater than 1, and i is an integer less than or equal to M;

Determine a comprehensive score corresponding to the i-th grid unit according to the measured line-of-sight information corresponding to the i-th grid unit and the satellite signal measurement information corresponding to the i-th grid unit; and

The positioning result of the mobile terminal is determined according to the comprehensive scores respectively corresponding to the M grid units.

According to one aspect of an embodiment of the present application, a positioning device for a mobile terminal is provided, the device comprising:

A data acquisition module, used to acquire a preliminary positioning position of the mobile terminal, determine building data of at least one building around the preliminary positioning position, and satellite position data of satellites around the preliminary positioning position;

a measurement information determination module, configured to determine, for an i-th grid cell among M grid cells located around the preliminary positioning position, measurement line of sight information corresponding to the i-th grid cell according to the building data and the satellite position data, where M is an integer greater than 1 and i is an integer less than or equal to M;

a comprehensive score determination module, configured to determine a comprehensive score corresponding to the ith grid unit according to the measured line-of-sight information corresponding to the ith grid unit and the satellite signal measurement information corresponding to the ith grid unit; and

The positioning result determination module is used to determine the positioning result of the mobile terminal according to the comprehensive scores corresponding to the M grid units respectively.

According to one aspect of an embodiment of the present application, a computer device is provided, which includes a processor and a memory, wherein the memory stores computer-readable instructions, and the computer-readable instructions are loaded and executed by the processor to implement the above-mentioned positioning method of the mobile terminal.

According to one aspect of an embodiment of the present application, a computer-readable storage medium is provided, in which computer-readable storage medium is stored computer-readable instructions, and the computer-readable instructions are loaded and executed by a processor to implement the above-mentioned positioning method of the mobile terminal.

According to one aspect of an embodiment of the present application, a computer program product is provided, the computer program product comprising computer-readable instructions, the computer-readable instructions being loaded and executed by a processor to implement the above-mentioned positioning method for a mobile terminal.

The details of one or more embodiments of the present application are set forth in the following drawings and description. Other features, objects, and advantages of the present application will become apparent from the description, drawings, and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the conventional technology, the drawings required for use in the embodiments or the conventional technology descriptions will be briefly introduced below. Obviously, the drawings described below are merely embodiments of the present application, and for ordinary technicians in this field, other drawings can be obtained based on the disclosed drawings without paying any creative work.

FIG1 is a schematic diagram of an implementation environment of a solution provided by an embodiment of the present application;

FIG2 is a flow chart of a method for positioning a mobile terminal provided by an embodiment of the present application;

FIG3 is a schematic diagram of the altitude angle of a satellite and the maximum altitude angle of a building provided by an embodiment of the present application;

FIG4 is a flow chart of a method for positioning a mobile terminal provided by an embodiment of the present application;

FIG5 is a schematic diagram of M grid units provided by an embodiment of the present application;

FIG6 is a grid diagram of a sight distance matching score based on building data and a carrier-to-noise ratio provided by one embodiment of the present application;

FIG7 is a schematic diagram of a grid based on pseudorange residual scores provided by an embodiment of the present application;

FIG8 is a grid diagram of a comprehensive score based on the line-of-sight matching degree and the pseudorange residual score provided by an embodiment of the present application;

FIG9 is a flow chart of a method for positioning a mobile terminal provided by an embodiment of the present application;

FIG10 is a schematic diagram showing a comparison between the actual position of a mobile terminal provided by an embodiment of the present application and the positioning position of the mobile terminal obtained using different positioning solution methods;

FIG11 is a schematic diagram of the positioning error and positioning effect of the technical solution of the present application provided by an embodiment of the present application;

FIG12 is a schematic diagram of a specific performance of the technical solution of the present application in a product application provided by an embodiment of the present application;

FIG13 is a block diagram of a positioning method for a mobile terminal provided in one embodiment of the present application;

FIG. 14 is a schematic diagram of the structure of a computer device provided in one embodiment of the present application.

Detailed ways

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

Before introducing the embodiments of the present application, in order to facilitate understanding of the present solution, the terms appearing in the present solution are explained as follows:

1.CORS (Continuously Operating Reference Stations) system: It is the product of the multi-faceted and in-depth crystallization of global satellite navigation technology, computer network technology, digital communication technology and other high-tech technologies. The CORS system consists of five parts: base station network, data processing center, data transmission system, positioning and navigation data broadcasting system, and user application system. Each base station and the monitoring and analysis center are connected to form a dedicated network through a data transmission system. It is to establish a number of continuously operating permanent reference stations within a certain area, and through network interconnection, it constitutes a new generation of networked GNSS integrated service system, which can not only provide accurate and continuous spatial benchmarks to surveying and mapping users at all levels, but also provide various data services to navigation, time, disaster prevention and other departments.

2. Line of sight (LOS): The propagation conditions of wireless communication systems are usually divided into two environments: line of sight (LOS) and non-line of sight (NLOS). Under line of sight conditions, wireless signals propagate in a straight line between the transmitter and the receiver without obstruction. Under non-line of sight conditions, that is, when there are obstacles, wireless signals can only reach the receiver through reflection, scattering and diffraction. At this time, the wireless signals are received through multiple channels, and the multipath effect will bring a series of problems such as delay asynchronization, signal attenuation, polarization change, link instability, etc.

Artificial Intelligence (AI) is the use of digital computers or machines controlled by digital computers. Theory, methods, technology and application system to simulate, extend and expand human intelligence, perceive the environment, acquire knowledge and use knowledge to obtain the best results. In other words, artificial intelligence is a comprehensive technology of computer science, which attempts to understand the essence of intelligence and produce a new intelligent machine that can respond in a similar way to human intelligence. Artificial intelligence is to study the design principles and implementation methods of various intelligent machines, so that machines have the functions of perception, reasoning and decision-making.

Artificial intelligence technology is a comprehensive discipline that covers a wide range of fields, including both hardware-level and software-level technologies. The basic technologies of artificial intelligence generally include sensors, dedicated artificial intelligence chips, cloud computing, distributed storage, big data processing technology, operation/interaction systems, mechatronics and other technologies. Artificial intelligence software technology mainly includes computer vision technology, speech processing technology, natural language processing technology, and machine learning/deep learning.

With the research and advancement of artificial intelligence technology, artificial intelligence technology has been studied and applied in many fields, such as common smart homes, smart wearable devices, virtual assistants, smart speakers, smart marketing, unmanned driving, automatic driving, drones, robots, smart medical care, smart customer service, etc. I believe that with the development of technology, artificial intelligence technology will be applied in more fields and play an increasingly important role.

The technical solution of this application mainly relates to the positioning solution technology in artificial intelligence technology, mainly to the positioning technology of mobile terminals.

Please refer to Figure 1, which shows a schematic diagram of a solution implementation environment provided by an embodiment of the present application. The solution implementation environment can be implemented as a positioning system for a mobile terminal. The solution implementation environment may include: a mobile terminal 101, a CORS system 102, and a server 103.

The mobile terminal 101 may be an electronic device such as a mobile phone, a tablet computer, a game console, an e-book reader, a multimedia player, a wearable device, a PC (Personal Computer), a vehicle-mounted terminal, etc. A client of a positioning solution program is installed in the mobile terminal 101, and the positioning solution program can be used to obtain the position of the mobile terminal 101. The mobile terminal 101 can receive satellite signals sent by different satellites, and then the global satellite navigation system can calculate the initial positioning position of the mobile terminal 101 according to the time information and distance information of the carrier signal received by the mobile terminal 101, and the positioning solution program in the mobile terminal 101 can obtain the initial positioning position of the mobile terminal 101 based on the global satellite navigation system.

The CORS system 102 is used to obtain building data around the preliminary positioning position of the mobile terminal 101, which may include, for example, the location and spatial information of the building, and to obtain ephemeris data, which may be used to calculate the coordinate positions of all satellites in the ECEF (Earth-Centered, Earth-Fixed) coordinate system. Based on the preliminary positioning position of the mobile terminal 101, the building data around the preliminary positioning position of the mobile terminal 101, and the coordinate positions of all satellites, the line-of-sight or non-line-of-sight situation of each satellite for the mobile terminal 101 can be calculated.

The server 103 is used to provide background services for the client of the positioning solution program installed and running in the mobile terminal 101. For example, the server 103 can be the background server of the above positioning solution program. The server 103 can be a single server, or a server cluster composed of multiple servers, or a cloud computing service center. Optionally, the server 103 provides background services for the clients of the positioning solution program in multiple mobile terminals 101 at the same time.

The mobile terminal 101 and the server 103 can communicate with each other via the network.

In an embodiment of the present application, a client of a positioning solution program is installed in the mobile terminal 101, and the server 103 can generate a number of grid units 104 according to the preliminary positioning position of the mobile terminal 101, and based on the line-of-sight or non-line-of-sight situation of each satellite for the mobile terminal 101, obtain the probability that the mobile terminal 101 is located in each grid unit, and then determine the final positioning position of the mobile terminal 101.

Please refer to FIG. 2, which shows a flow chart of a method for positioning a mobile terminal provided by an embodiment of the present application. The execution subject of each step of the method may be a computer device. The method may include at least one of the following steps 210 to 240:

Step 210, obtaining a preliminary positioning position of the mobile terminal, determining building data of at least one building around the preliminary positioning position, and satellite position data of satellites around the preliminary positioning position.

The building data includes the location and spatial information of the building, and the satellite location data includes the location coordinates of n satellites around the initial positioning location, where n is a positive integer.

The initial positioning position of a mobile terminal is the position obtained by positioning the mobile terminal. The initial positioning position is an approximate position that needs to be further corrected. The initial positioning position can be obtained through the global satellite navigation system. In cities, canyons, or scenarios where there are many buildings around the mobile terminal, the satellite signals received by the mobile terminal are easily affected by the surrounding buildings or three-dimensional terrain, resulting in large errors when the global satellite navigation system locates the position of the mobile terminal. For example, the mobile terminal is mistakenly located on the opposite street or adjacent block from the actual location. Therefore, the position obtained by the global satellite navigation system can be used as the preliminary positioning position, and the building data and satellite position data around the preliminary positioning position can be fully utilized to solve the position of the mobile terminal, thereby improving the positioning accuracy of the mobile terminal when the satellite signal is severely affected by urban buildings.

The building data includes the location and spatial information of at least one building around the preliminary positioning location, wherein the location of the building includes the orientation information and distance information between the building and the mobile terminal, and the spatial information of the building includes the three-dimensional information of the building, such as the horizontal width information, vertical width information and height information of the building.

The satellite position data includes the position coordinates of n satellites around the preliminary positioning position, where the n satellites include visible satellites whose satellite signals are transmitted to the mobile terminal without obstruction, and invisible satellites whose satellite signals are transmitted to the mobile terminal through obstacles. Satellites include but are not limited to BDS (BeiDou Navigation Satellite System), GPS (Global Positioning System), GALILEO (Galileo satellite navigation system), GLONASS (Global Navigation Satellite System), etc.

Step 220, for the i-th grid cell among the M grid cells located around the preliminary positioning position, determine the measurement line of sight information corresponding to the i-th grid cell according to the building data and the satellite position data, where M is an integer greater than 1 and i is an integer less than or equal to M.

Among them, the measured line-of-sight information corresponding to the i-th grid unit includes the measured line-of-sight results of each satellite. The measured line-of-sight result is the result of determining whether there is line-of-sight communication between the satellite and the mobile terminal when the mobile terminal is located in the i-th grid unit based on the obstruction of the building. When there is line-of-sight communication between the satellite and the mobile terminal located in the i-th grid unit, the i-th grid unit can receive the satellite signal sent by the satellite without obstruction.

Measuring line-of-sight information is to use the relative position relationship between the location of the grid unit and the buildings around the grid unit and the relative position relationship between the location of the grid unit and the satellite position to determine the line-of-sight or non-line-of-sight situation of each satellite for the mobile terminal located in different grid units. Based on the line-of-sight measurement results of each satellite, it can be determined whether each of the n satellites and the mobile terminal located in different grid units have line-of-sight communication.

It should be noted that the measured line-of-sight information may be presented in the form of a vector as a measured line-of-sight vector, and the measured line-of-sight vector includes the measured line-of-sight results of each satellite for different grid cells.

If the grid cell where the mobile terminal is located can receive the satellite signal sent by a certain satellite without obstruction, then the communication between the satellite and the mobile terminal located in the grid cell is line-of-sight (LOS), and the satellite can be determined as a visible satellite for the grid cell. If the grid cell where the mobile terminal is located can only receive the satellite signal sent by a certain satellite passing through an obstacle, then the communication between the satellite and the mobile terminal located in the grid cell is non-line-of-sight (NLOS), and the satellite can be determined as an invisible satellite for the grid cell.

i is an integer less than or equal to M, and the number of values of i is M. Optionally, i can be a positive integer from 1 to M, or an integer from 0 to M-1, which is not limited in the present application.

In some embodiments, determining the measured line-of-sight information corresponding to the i-th grid unit includes: for each of the n satellites, when the altitude angle of the satellite is less than the maximum altitude angle of the building, determining the predicted line-of-sight result of the satellite to be a third value, the third value being used to indicate that the satellite is an invisible satellite for non-line-of-sight communication with the mobile terminal; when the altitude angle of the satellite is greater than or equal to the maximum altitude angle of the building, determining the predicted line-of-sight result of the satellite to be a fourth value, the fourth value being used to indicate that the satellite is a visible satellite for line-of-sight communication with the mobile terminal.

The satellite elevation angle refers to the angle from the plane toward the satellite. For each of the n satellites, when the satellite elevation angle is less than the maximum elevation angle of the building, as shown in sub-figure b of Figure 3, is the altitude angle of the jth satellite among n satellites, is the altitude angle with the largest angle between the surrounding buildings and the mobile terminal when the mobile terminal is located in the i-th grid unit, that is, When When the satellite signal received from the jth satellite passes through an obstacle, it can be determined that the jth satellite is an invisible satellite blocked for the mobile terminal located in the ith grid unit, and the measured line of sight result of the jth satellite for the mobile terminal located in the ith grid unit is the third value.

When the satellite elevation angle is greater than or equal to the maximum elevation angle of the building, as shown in sub-graph a of FIG3, that is, when When , the satellite signal sent by the j-th satellite received by the mobile terminal located in the i-th grid unit does not pass through any obstacles, so it can be determined that the j-th satellite is an unobstructed visible satellite for the mobile terminal located in the i-th grid unit, and the measured line of sight result of the j-th satellite for the mobile terminal located in the i-th grid unit is the fourth value.

It should be noted that the third value and the fourth value are any numerical values between 0 and 1, and the values may include 0 and 1, and the third value is less than the fourth value, and the sum of the third value and the fourth value is 1. This application does not limit the specific numerical values of the third value and the fourth value.

For example, the measured line-of-sight results of n satellites based on building data can be expressed as:

Wherein, i is an integer less than or equal to M, j is an integer less than or equal to n, the third value is 0.2, and the fourth value is 0.8. Optionally, j can be a positive integer from 1 to n, or an integer from 0 to n-1, which is not limited in the present application.

According to the measurement results of the n satellites based on the building data, a corresponding measurement vector can be generated. For example, for n satellites and M grid cells, a measurement vector of n×M specifications can be generated, and one element in the measurement vector corresponds to the measurement result of a satellite for a mobile terminal located in one grid cell.

Through the relationship between the altitude angles of the above-mentioned satellites and the maximum altitude angles of the buildings around the mobile terminal, the measured line-of-sight information corresponding to each grid unit can be determined. Combining the building data is to obtain the line-of-sight or non-line-of-sight result corresponding to each grid unit from another perspective, so that the obtained line-of-sight or non-line-of-sight result can be combined with the actual environment and be more diverse.

Step 230, determining a comprehensive score corresponding to the ith grid cell based on the measured line-of-sight information corresponding to the ith grid cell and the satellite signal measurement information corresponding to the ith grid cell; wherein the satellite signal measurement information corresponding to the ith grid cell includes the signal quality measurement values of each satellite at the position of the ith grid cell; and the comprehensive score corresponding to the ith grid cell is used to indicate the probability that the mobile terminal is located in the ith grid cell.

Among them, the satellite signal measurement information corresponding to the i-th grid unit includes the signal quality measurement values of each satellite at the position of the i-th grid unit, and the comprehensive score corresponding to the i-th grid unit is used to indicate the probability that the mobile terminal is located in the i-th grid unit.

Exemplarily, the signal quality measurement value may be a carrier-to-noise ratio (C/N0), in dB/Hz. The carrier-to-noise ratio is used to represent the ratio of satellite signal power to noise power density, and is a standard measurement scale for the relationship between carrier and carrier noise. A high carrier-to-noise ratio indicates that better network acceptance rate and signal transmission quality can be provided, that is, the larger the value of the carrier-to-noise ratio, the better the signal transmission quality of the corresponding j-th satellite to the i-th grid unit.

According to the measured line-of-sight information corresponding to the ith grid unit and the signal quality measurement values of each satellite corresponding to the ith grid unit, the probability that the real position of the mobile terminal is located in the ith grid unit can be determined.

Step 240: Determine the positioning result of the mobile terminal according to the comprehensive scores corresponding to the M grid cells.

The higher the comprehensive score value corresponding to the i-th grid unit, the higher the probability that the real position of the mobile terminal is located in the grid unit; the lower the comprehensive score value corresponding to the i-th grid unit, the lower the probability that the real position of the mobile terminal is located in the grid unit. Therefore, the positioning result of the mobile terminal can be determined according to the positions of several grid units with higher comprehensive scores among the M grid units.

The technical solution provided in the embodiment of the present application determines the line-of-sight or non-line-of-sight state of each satellite for the mobile terminal at different positions by using the three-dimensional building information around the initial positioning position of the mobile terminal. It can be judged that when the mobile terminal is located at different positions in the urban environment, being blocked by the surrounding buildings will affect its reception of satellite signals, thereby The positioning solution program of the mobile terminal can correct the positioning result according to the interference information of the mobile terminal being blocked by the building, reduce the positioning error caused by the mobile terminal being blocked by the building, and improve the precision and accuracy of positioning.

Please refer to FIG. 4, which shows a flow chart of a method for positioning a mobile terminal provided by an embodiment of the present application. The execution subject of each step of the method may be a computer device. The method may include at least one of the following steps 410 to 450:

Step 410, obtaining a preliminary positioning position of the mobile terminal, determining building data of at least one building around the preliminary positioning position, and satellite position data of satellites around the preliminary positioning position.

Step 420, with the preliminary positioning position as the center, M grid cells are generated, wherein the M grid cells are arranged in a rows and b columns, and a and b are positive integers. For the i-th grid cell among the M grid cells located around the preliminary positioning position, the measurement line of sight information corresponding to the i-th grid cell is determined according to the building data and the satellite position data.

Exemplarily, a schematic diagram of generating M grid units with the preliminary positioning position as the center can refer to Figure 5, wherein the M grid units are arranged in 5 rows and 5 columns. Optionally, a and b may be equal or unequal. If a and b are equal, a×b square grid units may be generated; if a and b are unequal, a×b rectangular grid units may be generated. Wherein, M=a·b. This application does not limit the values of a and b. For example, a 80×80 square grid unit may also be generated.

Optionally, M grid cells may not be generated with the preliminary positioning position as the center, wherein the M grid cells are arranged in a rows and b columns, and a and b are positive integers. The preliminary positioning position of the mobile terminal may be the center position of any one of the M grid cells, or any position contained in any one of the grid cells, for example, the edge position of any one of the grid cells. Similarly, the position of the grid cell may be the center position of any one of the other M-1 grid cells except the grid cell at the preliminary positioning position, or any position contained in any one of the other M-1 grid cells, for example, the edge position of other grid cells may be used as the position of the grid cell.

This application does not limit the side length setting of each grid unit. For example, the side length of each grid unit can be set to any length such as 5 meters, 10 meters, etc. The smaller the side length setting value of the grid unit, the higher the accuracy of the final positioning solution result, which can be set independently according to actual application requirements.

By generating M grid cells with the preliminary positioning position as the center, the possibility of the real position of the mobile terminal can be summarized more accurately, thereby improving the accuracy of the positioning result.

In some embodiments, for the grid cells located outside the building among the M grid cells, the corresponding comprehensive scores are determined; for the grid cells located inside the building among the M grid cells, the corresponding comprehensive scores are not determined.

If there is a grid cell located inside a building among the M generated grid cells, the grid cell located inside the building does not have the problem of whether it is blocked by surrounding buildings to receive satellite signals. Therefore, the grid cell located inside the building does not participate in the positioning solution process of the mobile terminal. The possibility that the actual location of the mobile terminal is located in the grid cell located outside the building among the M grid cells can be judged.

If there is a grid cell located inside a building among the generated M grid cells, i is an integer less than M, and the number of values of i is less than M.

By excluding the positioning and solving process for the grid cells located inside the building and only calculating the corresponding comprehensive scores for the grid cells located outside the building, unnecessary calculation processes can be reduced, thereby reducing the operating pressure of the server in solving the true position of the mobile terminal and improving the efficiency of the server in determining the positioning results of the mobile terminal.

Step 430, determining a line of sight matching score corresponding to the ith grid cell based on the measured line of sight information corresponding to the ith grid cell and the satellite signal measurement information corresponding to the ith grid cell; wherein the line of sight matching score corresponding to the ith grid cell is used to indicate the similarity between the measured line of sight information corresponding to the ith grid cell and the predicted line of sight information corresponding to the ith grid cell.

The satellite signal measurement information corresponding to the ith grid unit includes the signal quality measurement values of each satellite at the position of the ith grid unit. For example, the line of sight matching score corresponding to the ith grid unit can be determined based on the measured line of sight information corresponding to the ith grid unit and the carrier-to-noise ratio of the jth satellite corresponding to the ith grid unit.

The predicted line-of-sight information is based on the transmission quality of the satellite signals sent by each satellite and the transmission quality of all satellite signals. The relationship between the quantities is calculated to predict the line-of-sight or non-line-of-sight situation of each satellite for mobile terminals located in different grid cells. Therefore, combined with the building data around the grid cell and the quality of satellite signal transmission received by the grid cell, according to the similarity between the measured line-of-sight information corresponding to the i-th grid cell and the predicted line-of-sight information corresponding to the i-th grid cell, the situation of the i-th grid cell being blocked by the building can be comprehensively obtained.

It should be noted that the predicted sight distance information can be presented in the form of a vector as a predicted sight distance vector, which includes the predicted sight distance results of each satellite for different grid cells. For example, the SSIM (Structural Similarity) indicator can be used as an indicator to evaluate the matching similarity between the measured sight distance information and the predicted sight distance information in each grid cell, that is, the sight distance matching score corresponding to each grid cell.

The larger the sight distance matching score corresponding to the ith grid unit, the higher the similarity between the measured sight distance information corresponding to the ith grid unit and the predicted sight distance information corresponding to the ith grid unit, the smaller the error of the possibility that the mobile terminal is located in the ith grid unit, and the higher the probability that the real position is located in the ith grid unit. Conversely, the smaller the sight distance matching score corresponding to the ith grid unit, the lower the similarity between the measured sight distance information corresponding to the ith grid unit and the predicted sight distance information corresponding to the ith grid unit, the larger the error of the possibility that the mobile terminal is located in the ith grid unit, and the lower the probability that the real position is located in the ith grid unit.

Step 430 includes at least one of the following sub-steps:

Step 431, based on the satellite signal measurement information corresponding to the ith grid cell, determine the predicted line-of-sight information corresponding to the ith grid cell; wherein the predicted line-of-sight information corresponding to the ith grid cell includes the predicted line-of-sight results of each satellite, and the predicted line-of-sight result refers to the result of whether there is line-of-sight communication between the satellite and the mobile terminal, assuming that the mobile terminal is located in the ith grid cell, and predicted based on the signal quality measurement value of the satellite.

Exemplarily, the predicted line-of-sight result corresponding to the ith grid unit can be determined according to the carrier-to-noise ratio of the jth satellite corresponding to the ith grid unit. According to the predicted line-of-sight results of each satellite, it can be determined whether there is line-of-sight communication between each of the n satellites and the mobile terminal located in different grid units.

In some embodiments, determining the predicted line-of-sight information corresponding to the i-th grid unit includes: for each of the n satellites, when the signal quality measurement value of the satellite is less than a minimum threshold value, determining the predicted line-of-sight result of the satellite to be a first value, the first value being used to indicate that the satellite is an invisible satellite for non-line-of-sight communication with a mobile terminal; when the signal quality measurement value of the satellite is greater than a maximum threshold value, determining the predicted line-of-sight result of the satellite to be a second value, the second value being used to indicate that the satellite is a visible satellite for line-of-sight communication with the mobile terminal; when the signal quality measurement value of the satellite is greater than the minimum threshold value and less than the maximum threshold value, determining the value of the predicted line-of-sight result of the satellite based on the signal quality measurement value of the satellite based on a linear regression fitting algorithm.

For example, the predicted line-of-sight results of n satellites based on the carrier-to-noise ratio can be expressed as:

Among them, a ₀ , a ₁ , and a ₂ are model parameters of linear regression fitting, and different satellites can fit different model parameters; min and max are thresholds of the carrier-to-noise ratio C/N0 in the above prediction model, min represents the minimum value of the carrier-to-noise ratio measurement values of all satellites for mobile terminals at different locations, and max represents the maximum value of the carrier-to-noise ratio measurement values of all satellites for mobile terminals at different locations; the first value is 0.2, and the second value is 0.8.

According to the predicted sight distance results of the n satellites based on the carrier-to-noise ratio, a corresponding predicted sight distance vector can be generated. For example, for n satellites and M grid cells, a predicted sight distance vector of n×M specifications can be generated, and one element in the predicted sight distance vector corresponds to the predicted sight distance result of a satellite for a mobile terminal located in one grid cell.

By generating the measured sight distance vector and the predicted sight distance vector of the same specification, it is helpful for the server to calculate the similarity between the measured sight distance information and the predicted sight distance information.

For each of the n satellites, when the measured value of the carrier-to-noise ratio of the jth satellite for the i-th grid unit is less than the minimum threshold value (min), it can be determined that the jth satellite is non-reliable for the mobile terminal located in the i-th grid unit. For an invisible satellite for line-of-sight communication, the predicted line-of-sight result of the j-th satellite for the mobile terminal located in the ith grid unit is a first value (such as 0.2). When the measured value of the carrier-to-noise ratio of the j-th satellite for the ith grid unit is greater than the minimum threshold value (max), it can be determined that the j-th satellite is a visible satellite for line-of-sight communication for the mobile terminal located in the ith grid unit, and the predicted line-of-sight result of the j-th satellite for the mobile terminal located in the ith grid unit is a second value (such as 0.8). When the measured value of the carrier-to-noise ratio of the j-th satellite for the ith grid unit is greater than the minimum threshold value (such as 0.2) and less than the maximum threshold value (such as 0.8), the predicted line-of-sight result of the j-th satellite for the mobile terminal located in the ith grid unit can be obtained based on a linear regression fitting algorithm (such as a ₀ ·C/N0 ² +a ₁ ·C/N0+a ₂ ).

It should be noted that the first value and the second value are any values between 0 and 1, and the values may include 0 and 1, and the first value is less than the second value, and the sum of the values of the first value and the second value is 1. The present application does not limit the specific values of the first value and the second value. Optionally, the first value may be the same as the third value, the second value may be the same as the fourth value, or the first value may be different from the third value, and the second value may be different from the fourth value.

Through the satellite signal transmission quality of each satellite to the mobile terminal at different positions, the line-of-sight or non-line-of-sight result corresponding to each grid unit based on the carrier-to-noise ratio can be predicted, so that the obtained line-of-sight or non-line-of-sight results can be more diverse.

Step 432 : Determine a sight distance matching score corresponding to the ith grid unit according to the similarity between the measured sight distance information corresponding to the ith grid unit and the predicted sight distance information corresponding to the ith grid unit.

Exemplarily, the SSIM (structural similarity) value corresponding to the ith grid unit may be determined according to the measured sight distance information corresponding to the ith grid unit and the predicted sight distance information corresponding to the ith grid unit.

In some embodiments, determining the sight distance matching score corresponding to the i-th grid unit includes:

1. Calculate the mean of the measured line-of-sight results of each satellite included in the measured line-of-sight information corresponding to the i-th grid unit to obtain a first mean; and calculate the mean of the predicted line-of-sight results of each satellite included in the predicted line-of-sight information corresponding to the i-th grid unit to obtain a second mean.

Exemplarily, according to the measured line-of-sight results (LOS|Building) of each satellite for the mobile terminal located in different grid cells, a first mean value μ _X based on the measured line-of-sight results can be calculated, for example, the first mean value μ _X can be obtained based on the measured line-of-sight vector; according to the predicted line-of-sight results (LOS|C/N0) of each satellite for the mobile terminal located in different grid cells, a second mean value μ _Y based on the predicted line-of-sight results can be calculated, for example, the first mean value μ _Y can be obtained based on the predicted line-of-sight vector. Wherein, X corresponds to the measured line-of-sight result, and Y corresponds to the measured line-of-sight result.

2. Calculate the standard deviation of the measured line-of-sight results of each satellite included in the measured line-of-sight information corresponding to the i-th grid unit to obtain a first standard deviation; and calculate the standard deviation of the predicted line-of-sight results of each satellite included in the predicted line-of-sight information corresponding to the i-th grid unit to obtain a second standard deviation.

Exemplarily, according to the measured line-of-sight results (LOS|Building) of each satellite for the mobile terminal located in different grid cells, a first standard deviation σ _X based on the measured line-of-sight results can be calculated, for example, the first standard deviation σ _X can be obtained based on the measured line-of-sight vector; according to the predicted line-of-sight results (LOS|C/N0) of each satellite for the mobile terminal located in different grid cells, a second standard deviation σ _Y based on the predicted line-of-sight results can be calculated, for example, the second standard deviation σ _Y can be obtained based on the measured line-of-sight vector.

3. Calculate a first similarity parameter based on the first mean and the second mean.

Exemplarily, according to the first mean μ _X and the second mean μ _Y , the first similarity parameter L(X, Y) is calculated and can be expressed as:

Among them, _C1 is a custom parameter, which is introduced mainly to avoid the situation where the denominator is zero. _C1 can take the value of 0.01.

4. Calculate a second similarity parameter based on the first standard deviation and the second standard deviation.

Exemplarily, according to the first standard deviation σ _X and the second standard deviation σ _Y , the second similarity parameter C(X, Y) is calculated and can be expressed as:

Among them, C ₂ is a custom parameter, which is introduced mainly to avoid the situation where the denominator is zero. C ₂ can take the value of 0.02. Optionally, the value of C ₂ can be the same as C ₁ or different from C ₁ .

5. A third similarity parameter is calculated based on the first standard deviation, the second standard deviation, and the covariance of the first mean and the second mean.

Exemplarily, according to the first mean μ _X and the second mean μ _Y , and the first standard deviation σ _X and the second standard deviation σ _Y , the covariance σ _XY of the first mean μ _X and the second mean μ _Y is calculated and can be expressed as:

Wherein, E(X-μ _X ) represents the mathematical expectation of the first mean μ _X , and E(Y-μ _Y ) represents the mathematical expectation of the second mean μ _Y .

According to the first standard deviation σ _X , the second standard deviation σ _Y , the covariance σ _XY of the first mean μ _X and the second mean μ _Y , the third similarity parameter S(X,Y) is calculated and can be expressed as:

Among them, C ₃ is a custom parameter, which is introduced mainly to avoid the situation where the denominator is zero. C ₃ can take the value of 0.03. Optionally, the value of C ₃ can be the same as C ₁ or C ₂ , or different from C ₁ or C ₂ .

6. Based on the first similarity parameter, the second similarity parameter and the third similarity parameter, the similarity between the measured viewing distance information corresponding to the ith grid unit and the predicted viewing distance information corresponding to the ith grid unit is calculated.

Exemplarily, according to the first similarity parameter L(X,Y), the second similarity parameter C(X,Y) and the third similarity parameter S(X,Y), the SSIM value corresponding to the i-th grid unit is calculated and can be expressed as:
SSIM = L(X,Y)·C(X,Y)·S(X,Y)

According to the SSIM values corresponding to the above M grid units, a corresponding sight distance matching vector may be generated. For example, a sight distance matching vector of M×1 specification may be generated. An element in the sight distance matching vector corresponds to a sight distance matching score corresponding to a grid unit.

The larger the SSIM value, the higher the similarity between the measured line-of-sight information and the predicted line-of-sight information in the grid cell, and the greater the probability that the mobile terminal is located in the grid cell; the smaller the SSIM value, the lower the similarity between the measured line-of-sight information and the predicted line-of-sight information in the grid cell, and the smaller the probability that the mobile terminal is located in the grid cell.

By combining the building data around the grid cell and the satellite signal transmission quality received by the grid cell, the line-of-sight matching score corresponding to each grid cell is obtained, so that the obtained line-of-sight matching score can more accurately represent the probability that the mobile terminal is located in the grid cell, thereby improving the accuracy of the positioning result.

FIG6 shows a grid diagram of the sight distance matching score based on building data and carrier-to-noise ratio. The lighter the color corresponding to the grid unit in FIG6, the higher the similarity between the measured sight distance information and the predicted sight distance information in the grid unit, and the greater the probability that the real position of the mobile terminal is located in the grid unit. The several light-colored areas 601 shown in FIG6 are areas with a high probability of the real position of the mobile terminal. The darker the color corresponding to the grid unit, the lower the similarity between the measured sight distance information and the predicted sight distance information in the grid unit, and the lower the probability that the real position of the mobile terminal is located in the grid unit.

Step 440, determining the pseudorange residual score corresponding to the ith grid cell based on the measured line-of-sight information corresponding to the ith grid cell and the satellite signal measurement information corresponding to the ith grid cell; wherein the pseudorange residual score corresponding to the ith grid cell is used to indicate the comprehensive pseudorange residual of the pseudorange residual of the visible satellite and the pseudorange residual of the invisible satellite.

According to the measured line of sight information corresponding to the ith grid unit and the signal quality measurement values of each satellite corresponding to the ith grid unit, the reference satellite among the n satellites can be determined. Then, according to the position of the satellite, the position of each grid unit, and the initial positioning position of the mobile terminal, the pseudorange residual of each satellite can be determined, and then the pseudorange residual score corresponding to each grid unit can be obtained.

The pseudorange residual score can be used to indicate the probability that the mobile terminal is located in each grid unit. The larger the pseudorange residual score value corresponding to the ith grid unit, the higher the probability that the real position of the mobile terminal is located in the ith grid unit. Conversely, the smaller the pseudorange residual score value corresponding to the ith grid unit, the lower the probability that the real position of the mobile terminal is located in the ith grid unit.

Step 440 includes at least one of the following sub-steps:

Step 441, determining a reference satellite from n satellites based on the signal quality measurement values and elevation angles of each satellite at the position of the i-th grid unit, where the reference satellite refers to a visible satellite with the lowest probability of being blocked for the mobile terminal among the n satellites.

In the M grid cells, the obstruction probability of each satellite among the n satellites for the mobile terminal located in different grid cells is determined according to the altitude angle and the carrier-to-noise ratio of each satellite, and the satellite with the lowest obstruction probability is selected as the reference satellite from the n obstruction probabilities.

In some embodiments, determining a reference satellite from n satellites includes: for each visible satellite among the n satellites, determining a measurement index of the obstruction of each visible satellite for the mobile terminal based on the signal quality measurement value and altitude angle of each visible satellite at the position of the i-th grid unit; and determining the visible satellite corresponding to the measurement index with the largest value among the measurement indexes as the reference satellite.

For example, the product of the carrier-to-noise ratio and the elevation angle of each visible satellite can be used as an indicator to measure the shielding condition of each visible satellite for the mobile terminal located in the i-th grid unit. The measurement indicator can be expressed as:
score _i =θ _i ·C/N0 _i

Among them, θ _i represents the altitude angle of the jth visible satellite for the ith grid unit, and C/N0 _i represents the measured value of the carrier-to-noise ratio of the jth visible satellite for the ith grid unit. The larger the satellite altitude angle θ _i and the larger the carrier-to-noise ratio C/N0 _i , the larger the value of the measurement index score _i , which means that the probability of the jth visible satellite being blocked for the i-th grid unit is lower.

According to the measurement index of the jth visible satellite for the ith grid unit, the comprehensive measurement index of each visible satellite for the M grid units can be determined. For example, the measurement index of each visible satellite for each grid unit can be added to obtain the comprehensive measurement index of each visible satellite for the M grid units. Furthermore, the visible satellite corresponding to the comprehensive measurement index with the largest value can be selected from at least one comprehensive measurement index as a reference satellite.

By determining the reference satellite from the visible satellites among the n satellites, the steps of calculating the measurement index of the invisible satellite are reduced, and unnecessary calculation processes are avoided, thereby reducing the operating pressure of the server computing the measurement index and improving the computing efficiency of the server.

Step 442, determine the receiver clock error of the ith grid unit based on the distance between the ith grid unit and the reference satellite, and the distance between the preliminary positioning position and the reference satellite.

Exemplarily, the distance between the i-th grid unit and the reference satellite, and the distance difference between the preliminary positioning position and the reference satellite, can be expressed as ||r _ref -r _{cell_ref} ||, where r _ref represents the distance between the preliminary positioning position of the mobile terminal and the reference satellite, and r _{cell_ref} represents the distance between the i-th grid unit and the reference satellite.

The receiver clock error (user clock error) refers to the signal propagation time measurement error caused by the instability of the satellite navigation receiver clock. Since the reference satellite is the satellite with the lowest probability of being blocked for M grid cells, the pseudorange residual of the reference satellite can be approximated to the receiver clock error when each grid cell receives the satellite signal, which can be used to correct the pseudoranges of the remaining satellites.

Step 443, determining the pseudorange residual score corresponding to the ith grid unit based on the receiver clock error of the ith grid unit and the pseudoranges of each satellite, where the pseudorange of the satellite includes the distance between the grid unit and the satellite and the distance between the initial positioning position and the satellite.

The pseudorange of the jth satellite includes the distance between the ith grid unit and the jth satellite, and the distance between the initial positioning position of the mobile terminal and the jth satellite.

By using the receiver clock error to correct the pseudorange of each satellite, a more accurate pseudorange residual of each satellite can be obtained, thereby obtaining a more accurate pseudorange residual score corresponding to each grid unit.

In some embodiments, determining the pseudorange residual score corresponding to the i-th grid unit includes:

1. Determine the pseudorange residual corresponding to the ith grid unit based on the receiver clock error and distance difference of the ith grid unit; the distance difference refers to the distance difference between the ith grid unit and the satellite and the distance difference between the initial positioning position and the satellite.

Exemplarily, according to the receiver clock error ||r _ref -r _{cell_ref} || and the distance difference of the ith grid cell, the pseudorange residual v _i corresponding to the ith grid cell is calculated and can be expressed as:
v _i =||r _i -r _{cell_i} ||-||r _ref -r _{cell_ref} ||

Wherein, || _ri - _{rcell_i} || represents the distance difference of the i-th grid cell, _ri represents the distance between the initial positioning position of the mobile terminal and the j-th satellite, and _{rcell_i} represents the distance between the i-th grid cell and the j-th satellite.

2. Determine the standard deviation of the pseudorange of each satellite based on the altitude angle and signal quality measurement values of each satellite.

Exemplarily, according to the altitude angle θ _i of the j-th satellite for the i-th grid unit and C/N0 _i of the j-th satellite for the i-th grid unit, the standard deviation σ _i of the pseudorange of the j-th satellite for the i-th grid unit is calculated and can be expressed as:

Among them, a and b are empirical parameters, and this application does not limit the values of a and b. For example, a can be 1, and b can be 281.

3. According to the pseudorange residual corresponding to the i-th grid cell and the pseudorange standard deviation of each satellite, the pseudorange residual term of the visible satellite and the pseudorange residual term of the invisible satellite are determined.

For example, according to the pseudorange residual v _i corresponding to the ith grid cell and the pseudorange standard deviation σ _i of the jth satellite for the ith grid cell, the pseudorange residual term of the visible satellite corresponding to the ith grid cell can be calculated: The pseudorange residual term of the invisible satellite corresponding to the i-th grid cell

Wherein, s corresponds to the visible satellite, and t corresponds to the invisible satellite. The pseudorange residual term of the visible satellite represents the pseudorange residual index of the visible satellite, and the pseudorange residual term of the invisible satellite represents the pseudorange residual index of the invisible satellite.

4. Determine the pseudorange residual score corresponding to the i-th grid cell based on the pseudorange residual term of the satellite obtained from the pseudorange residual term of the visible satellite and the pseudorange residual term of the invisible satellite.

Exemplarily, according to the pseudorange residual term of the visible satellite corresponding to the i-th grid unit and the pseudorange residual term of the invisible satellite corresponding to the i-th grid unit, the satellite pseudorange residual term corresponding to the i-th grid unit is calculated, which can be expressed as:

According to the satellite pseudorange residual term residual corresponding to the ith grid cell, the pseudorange residual score res_score corresponding to the ith grid cell is calculated and can be expressed as:

According to the pseudorange residual scores corresponding to the above M grid units, a corresponding pseudorange residual vector may be generated. For example, a pseudorange residual vector of M×1 specification may be generated, and one element in the pseudorange residual vector corresponds to a pseudorange residual score corresponding to one grid unit.

By generating the sight range matching vector and pseudorange residual vector of the same specification, it is helpful for the server to calculate the comprehensive score corresponding to each grid unit based on the sight range matching vector and the pseudorange residual vector.

In each grid cell, the reception of satellite signals from visible satellites can be free from interference from surrounding buildings. The satellite signals sent by invisible satellites will have large measurement errors due to the influence of reflection or refraction from buildings. Therefore, the line-of-sight or non-line-of-sight conditions close to the true point grid unit are more in line with the actual measurement characteristics. Therefore, when the reference satellite is effectively selected and the influence of the receiver clock error is reduced, the smaller the pseudo-range residual terms of the visible satellite and the invisible satellite calculated by the above formula are, the higher the pseudo-range residual score value corresponding to the grid unit is. In the grid unit far away from the true value, since the judgment of line-of-sight or non-line-of-sight is more likely to be inconsistent with the actual situation, there is a higher possibility that the visible satellite is mistakenly judged as an invisible satellite, or the invisible satellite is mistakenly judged as a visible satellite, which will cause the pseudo-range residual terms of the visible satellite and the invisible satellite to be larger, so the pseudo-range residual score corresponding to the grid unit is correspondingly lower.

By calculating the receiver clock error and correcting the pseudorange residuals of each satellite, the accuracy of calculating the pseudorange residual terms of visible and invisible satellites is improved, thereby improving the accuracy of calculating the pseudorange residual score corresponding to each grid unit, which is beneficial to improving the accuracy of the positioning result.

FIG7 shows a schematic diagram of a grid based on a pseudorange residual score. The lighter the color corresponding to the grid unit in FIG7, the higher the pseudorange residual score value corresponding to the grid unit, and the greater the probability that the real position of the mobile terminal is located in the grid unit. The light-colored area 701 shown in FIG7 is the area with the largest probability value of the real position of the mobile terminal. The darker the color corresponding to the grid unit, the lower the pseudorange residual score value corresponding to the grid unit, and the smaller the probability that the real position of the mobile terminal is located in the grid unit.

Step 450 : Determine a comprehensive score corresponding to the ith grid cell according to the sight range matching score corresponding to the ith grid cell and the pseudorange residual score corresponding to the ith grid cell.

By combining the line-of-sight matching score corresponding to each grid cell and the pseudo-range residual score corresponding to each grid cell, a comprehensive score corresponding to each grid cell can be obtained. The comprehensive score can be used to comprehensively represent the probability that the mobile terminal is located in each grid cell.

For example, the product of the SSIM line-of-sight matching degree and the pseudorange residual score can be calculated in each grid and the square root can be taken as the comprehensive score corresponding to the i-th grid unit. The comprehensive score corresponding to the i-th grid unit can be expressed as:

The higher the comprehensive score value corresponding to the i-th grid unit, the higher the probability that the real location of the mobile terminal is located in the i-th grid unit, and the lower the comprehensive score value corresponding to the i-th grid unit, the lower the probability that the real location of the mobile terminal is located in the i-th grid unit.

FIG8 shows a grid diagram of a comprehensive score based on the line-of-sight matching degree and the pseudo-range residual score. The lighter the color corresponding to the grid unit in FIG8, the higher the comprehensive score value corresponding to the grid unit, and the greater the probability that the real position of the mobile terminal is located in the grid unit. The light-colored area 801 shown in FIG8 is the area with the largest probability value of the real position of the mobile terminal. The darker the color corresponding to the grid unit, the lower the comprehensive score value corresponding to the grid unit, and the smaller the probability that the real position of the mobile terminal is located in the grid unit.

The technical solution provided in the above embodiment combines the line-of-sight matching score corresponding to each grid cell and the pseudorange residual score corresponding to each grid cell to obtain a comprehensive score that can comprehensively characterize the probability that the mobile terminal is located in each grid cell. The calculation source of the comprehensive score is more comprehensive, which improves the accuracy of judging the probability that the mobile terminal is located in each grid cell, thereby improving the accuracy of the positioning result.

Please refer to Figure 9, which shows a flow chart of a positioning method for a mobile terminal provided by an embodiment of the present application. The execution subject of each step of the method may be a computer device. The method may include at least one of the following steps 910 to 960:

Step 910: Acquire the preliminary positioning position of the mobile terminal, determine the building data of at least one building around the preliminary positioning position, and the satellite position data of the satellites around the preliminary positioning position.

Step 920, for the i-th grid cell among the M grid cells located around the preliminary positioning position, determine the measurement line of sight information corresponding to the i-th grid cell according to the building data and the satellite position data, where M is an integer greater than 1 and i is an integer less than or equal to M.

Step 930, determining a comprehensive score corresponding to the ith grid unit according to the measured line-of-sight information corresponding to the ith grid unit and the satellite signal measurement information corresponding to the ith grid unit.

For the description of steps 910 to 930 , please refer to the above embodiment, which will not be described again here.

Step 940: According to the comprehensive scores corresponding to the M grid units, a grid unit corresponding to the comprehensive score that meets the first condition is selected.

Exemplarily, the first condition may be a threshold condition. For example, the comprehensive score that satisfies the first condition may be a comprehensive score that satisfies the M comprehensive scores and is greater than the first threshold. In the grid diagram of the comprehensive score shown in FIG8 , the first threshold may be 0.150, 0.160, 0.175, etc., and the grid cell corresponding to the comprehensive score whose value is greater than the first threshold among the M comprehensive scores may be selected.

The comprehensive score that meets the first condition may also be a comprehensive score that meets the second threshold among the M comprehensive scores. The second threshold may be 5%. Then the grid unit corresponding to the comprehensive score that ranks in the top 5% among the M comprehensive scores may be selected.

Step 950: divide the selected grid unit into at least one connected area, each connected area containing at least one selected grid unit.

A connected region refers to a grid region composed of adjacent selected grid cells. For example, a two-pass filter can be used to divide the selected grid cells into at least one connected region, each of which contains at least one selected grid cell.

Step 960: Determine the positioning result of the mobile terminal according to the positions and comprehensive scores of the grid cells included in each connected area, and the number of grid cells included in each connected area.

Here, the position of the grid unit may be the center position of each grid unit, or may be any position contained in each grid unit, such as the edge position of the grid unit.

Step 960 includes at least one of the following sub-steps:

Step 961: for each connected region, determine the weights of the grid cells included in the connected region according to the comprehensive scores of the grid cells included in the connected region and the maximum and minimum values of the comprehensive scores that meet the first condition.

The maximum value of the comprehensive scores satisfying the first condition is recorded as max _{grid_score} , and the minimum value of the comprehensive scores satisfying the first condition is recorded as min _{grid_score} . Exemplarily, the weight w _i of the i-th grid unit contained in each connected region can be expressed as:

Among them, grid_score _i represents the comprehensive score corresponding to the i-th grid unit, and num represents the number of selected grid units, that is, the number of grid units corresponding to the comprehensive scores that meet the first condition.

Step 962, determining a probability value of the connected area according to the weights of the grid cells contained in the connected area and the number of grid cells contained in the connected area, wherein the probability value of the connected area is used to indicate the probability that the mobile terminal is located in the connected area.

Exemplarily, according to the weight w _ki of the ith grid unit included in the kth connected region and the number of grid units included in the kth connected region, the probability value prob _k that the mobile terminal is located in the kth connected region is calculated and can be expressed as:

Among them, grid_num _k represents the number of grid cells contained in the kth connected region, and the maximum value of k is the number of selected grid cells.

Step 963: In the connected area with the largest probability value, based on the proximity algorithm, the positioning result of the mobile terminal is determined according to the positions of each grid unit in the connected area with the largest probability value and the number of grid units contained in the connected area with the largest probability value.

A connected area with the largest prob _k value is selected from the probability values of the k connected areas. For example, based on a K-Nearest Neighbor (KNN) algorithm, the positioning result of the mobile terminal is calculated according to the positions of each grid unit in the connected area with the largest probability value and the number of grid units included in the connected area with the largest probability value, which can be expressed as:

Among them, w _i represents the weight of the i-th grid unit contained in the connected area with the largest probability value, (lon _i , lat _i ) is the position coordinate value of the i-th grid unit in the connected area with the largest probability value, grid_num represents the number of grid units contained in the connected area with the largest probability value, and (lon _final , lat _final ) is the final positioning position coordinate value of the mobile terminal.

The technical solution provided by the above embodiment determines the final positioning result by dividing the grid cells with higher scores into connected areas again after determining the comprehensive score corresponding to the mobile terminal, and calculating the probability value of the mobile terminal being located in each connected area. This avoids the situation where the mobile terminal is not located in the grid cell with the highest comprehensive score, reduces the error generated in the calculation process of the comprehensive score, and improves the accuracy of the positioning result of the mobile terminal.

FIG10 shows a schematic diagram comparing the actual position of a mobile terminal and the positioning position of the mobile terminal obtained using different positioning solution methods. As shown in FIG10 sub-figure a, the dark large dot represents the actual position of the mobile terminal, the dark small dot represents the positioning position obtained using GNSS, the polygons in the figure represent the surrounding buildings, and the numbers on the polygons represent the heights of the various buildings. It can be seen that the positioning position obtained using GNSS is blocked by the surrounding buildings, resulting in the positioning solution result deviating to the opposite block of the actual position of the mobile terminal, and there is a large position difference between the actual position of the mobile terminal. As shown in FIG10 sub-figure b, the light small dot represents the positioning position obtained using the technical solution of the present application. It can be seen that compared with the positioning position obtained using GNSS, the accuracy of the positioning position obtained using the technical solution of the present application has been significantly improved, and there are many light small dots that overlap with the positions of the dark large dots. The positioning position obtained using the technical solution of the present application does not deviate much from the actual position of the mobile terminal, and they are all located on the same road in the same block, which effectively corrects the positioning error of the global navigation positioning system and improves the positioning accuracy.

In order to verify the actual effect of the technical solution of this application, more than 700 GNSS original measurement data and actual positions of mobile terminals were collected from different locations in four cities, including Beijing, Shanghai, Shenzhen, and Hangzhou, with many buildings blocking the scene, and the positioning error and positioning effect of each data were calculated, as shown in Figure 11:

Sub-figure a of Figure 11 shows a schematic diagram comparing the positioning error of the technical solution of the present application and the GNSS positioning error. The dark rectangular columns in the figure represent the positioning error of the technical solution of the present application, and the light rectangular columns represent the positioning error of the GNSS positioning results. From the comparison results of sub-figure a of Figure 11, it can be seen that, except for the positioning results for Shanghai, the dark rectangular columns for the other three cities, Shenzhen, Hangzhou and the background are all lower than the light rectangular columns. Therefore, in general, the positioning error of the technical solution of the present application is smaller than the positioning error of the GNSS positioning results, and the positioning effect of the technical solution of the present application is better.

Sub-figure b of Figure 11 shows a schematic diagram of the positioning effect of the technical solution of the present application. Among them, GNSS is excellent, which means that the positioning effect of GNSS is better than that of the technical solution of the present application, and GNSS is excellent, accounting for 12.62%; Poor, which means that the positioning effect of the technical solution of the present application deviates from the true positioning effect than the positioning effect of GNSS, and Poor, accounting for 6.38%; Substantial optimization of the present application means that the positioning effect of the technical solution of the present application is greatly improved compared with the positioning effect of GNSS, and the substantial optimization of the present application accounts for 15.74%. For example, if the positioning result of GNSS differs from the actual result by 100 meters, and the technical solution of the present application differs from the actual result by 10 meters, then the positioning effect belongs to the substantial optimization of the present application; Slightly optimized of the present application means that the positioning effect of the technical solution of the present application is slightly improved compared with the positioning effect of GNSS, and the slight optimization of the present application accounts for 17.02%. For example, if the positioning result of GNSS differs from the actual result by 20 meters, and the technical solution of the present application differs from the actual result by 10 meters, then the positioning effect belongs to the slight optimization of the present application; Similar means that the positioning effect of the technical solution of the present application is similar to the positioning effect of GNSS, and there is no significant improvement in the positioning effect of one party.

From the results in sub-figure b of Figure 11, it can be seen that the positioning results of the technical solution of the present application are better than the positioning results of GNSS (i.e., including the parts slightly optimized and greatly optimized by the present application) at a ratio of 32.78%, while the positioning results of the technical solution of the present application are worse than the positioning results of GNSS (including the parts with good and bad GNSS) at a ratio of 19%. It can be seen that the positioning effect of the technical solution of the present application is better than that of GNSS in the urban multi-building occlusion scene.

FIG12 is a schematic diagram showing the specific performance of the technical solution of the present application in product applications. The mark 1201 of the mobile terminal in FIG12 indicates the actual position of the mobile terminal, the positioning mark 1202 indicates the positioning solution result of the mobile terminal based on GNSS, and the positioning mark 1203 indicates the positioning solution result obtained by the mobile terminal based on the technical solution of the present application. It can be clearly seen from FIG12 that the positioning position obtained using the technical solution of the present application is closer to the actual position of the mobile terminal than the positioning position obtained using GNSS, and the positioning precision and accuracy have been significantly improved.

The following are device embodiments of the present application, which can be used to execute the method embodiments of the present application. For details not disclosed in the device embodiments of the present application, please refer to the method embodiments of the present application.

Please refer to Figure 13, which shows a block diagram of a positioning device for a mobile terminal provided by an embodiment of the present application. The device has the function of implementing the positioning method of the above-mentioned mobile terminal, and the function can be implemented by hardware, or by hardware executing corresponding software. The device can be the mobile terminal introduced above, and can also be set in a mobile terminal. As shown in Figure 13, the device 1300 may include: a data acquisition module 1310, a measurement information determination module 1320, a comprehensive score determination module 1330 and a positioning result determination module 1340.

The data acquisition module 1310 is used to acquire the preliminary positioning position of the mobile terminal, determine the building data of at least one building around the preliminary positioning position, and the satellite position data of the satellites around the preliminary positioning position.

The measurement information determination module 1320 is used to determine the measurement line of sight information corresponding to the i-th grid cell among the M grid cells located around the preliminary positioning position based on the building data and the satellite position data, where M is an integer greater than 1 and i is an integer less than or equal to M.

The comprehensive score determination module 1330 is used to determine the comprehensive score corresponding to the ith grid cell based on the measured line-of-sight information corresponding to the ith grid cell and the satellite signal measurement information corresponding to the ith grid cell; wherein the satellite signal measurement information corresponding to the ith grid cell includes the signal quality measurement values of each satellite at the position of the ith grid cell; the comprehensive score corresponding to the ith grid cell is used to indicate the probability that the mobile terminal is located in the ith grid cell.

The positioning result determination module 1340 is used to determine the positioning result of the mobile terminal according to the comprehensive scores corresponding to the M grid units.

In some embodiments, the building data includes the location and spatial information of the building, and the satellite location data includes the location coordinates of n satellites around the preliminary positioning location, where n is a positive integer.

In some embodiments, the measured line-of-sight information corresponding to the i-th grid unit includes the measured line-of-sight results of each satellite. The measured line-of-sight results are the results of determining whether there is line-of-sight communication between the satellite and the mobile terminal when the mobile terminal is located in the i-th grid unit based on the obstruction of the building. When there is line-of-sight communication between the satellite and the mobile terminal located in the i-th grid unit, the i-th grid unit can receive the satellite signal sent by the satellite without obstruction.

In some embodiments, the satellite signal measurement information corresponding to the i-th grid unit includes the signal quality measurement values of each satellite at the position of the i-th grid unit, and the comprehensive score corresponding to the i-th grid unit is used to indicate the probability that the mobile terminal is located in the i-th grid unit.

In some embodiments, the comprehensive score determination module 1330 includes:

A line of sight score determination unit is used to determine a line of sight matching score corresponding to the ith grid unit based on the measured line of sight information corresponding to the ith grid unit and the satellite signal measurement information corresponding to the ith grid unit; wherein the line of sight matching score corresponding to the ith grid unit is used to indicate the similarity between the measured line of sight information corresponding to the ith grid unit and the predicted line of sight information corresponding to the ith grid unit.

The pseudorange score determination unit is used to determine the pseudorange residual score corresponding to the ith grid cell according to the measured line of sight information corresponding to the ith grid cell and the satellite signal measurement information corresponding to the ith grid cell; wherein the pseudorange residual score corresponding to the ith grid cell is used to indicate the comprehensive pseudorange residual of the pseudorange residual of the visible satellite and the pseudorange residual of the invisible satellite.

A comprehensive score determination unit is used to determine the score of the line of sight matching corresponding to the i-th grid unit and the i-th grid unit. The corresponding pseudorange residual score determines the comprehensive score corresponding to the i-th grid unit.

In some embodiments, the sight distance score determination unit comprises:

The predicted line-of-sight determination subunit is used to determine the predicted line-of-sight information corresponding to the ith grid unit based on the satellite signal measurement information corresponding to the ith grid unit; wherein the predicted line-of-sight information corresponding to the ith grid unit includes the predicted line-of-sight results of each satellite, and the predicted line-of-sight result refers to the result of whether there is line-of-sight communication between the satellite and the mobile terminal, assuming that the mobile terminal is located in the ith grid unit and obtained by predicting the signal quality measurement value of the satellite.

The sight distance score determination subunit is used to determine the sight distance matching score corresponding to the ith grid unit according to the similarity between the measured sight distance information corresponding to the ith grid unit and the predicted sight distance information corresponding to the ith grid unit.

In some embodiments, the predicted sight distance determination subunit is configured to:

For each of the n satellites, when the signal quality measurement value of the satellite is less than a minimum threshold value, determining that the predicted line-of-sight result of the satellite is a first value, where the first value is used to indicate that the satellite is an invisible satellite for non-line-of-sight communication with the mobile terminal;

When the signal quality measurement value of the satellite is greater than the maximum threshold value, determining that the predicted line-of-sight result of the satellite is a second value, the second value is used to indicate that the satellite is a visible satellite for line-of-sight communication with the mobile terminal;

When the signal quality measurement value of the satellite is greater than the minimum threshold value and less than the maximum threshold value, the value of the predicted line of sight result of the satellite is determined according to the signal quality measurement value of the satellite based on a linear regression fitting algorithm.

In some embodiments, the sight distance score determination subunit is configured to:

Calculate the mean of the measured sight distance results of each satellite included in the measured sight distance information corresponding to the i-th grid unit to obtain a first mean value; and calculate the mean of the predicted sight distance results of each satellite included in the predicted sight distance information corresponding to the i-th grid unit to obtain a second mean value;

Calculating the standard deviation of the measured sight distance results of each satellite included in the measured sight distance information corresponding to the i-th grid unit to obtain a first standard deviation; and calculating the standard deviation of the predicted sight distance results of each satellite included in the predicted sight distance information corresponding to the i-th grid unit to obtain a second standard deviation;

Calculate a first similarity parameter according to the first mean and the second mean;

Calculating a second similarity parameter according to the first standard deviation and the second standard deviation;

Calculate a third similarity parameter according to the first standard deviation, the second standard deviation, and the covariance of the first mean and the second mean;

The similarity between the measured viewing distance information corresponding to the ith grid unit and the predicted viewing distance information corresponding to the ith grid unit is calculated based on the first similarity parameter, the second similarity parameter and the third similarity parameter.

In some embodiments, the pseudorange score determination unit comprises:

The reference satellite determination subunit is used to determine a reference satellite from n satellites based on the signal quality measurement values and altitude angles of each satellite at the position of the i-th grid unit. The reference satellite refers to a visible satellite with the lowest probability of being blocked for the mobile terminal among the n satellites.

The receiver clock error determination subunit is used to determine the receiver clock error of the ith grid unit according to the distance between the ith grid unit and the reference satellite, and the distance between the preliminary positioning position and the reference satellite.

The pseudorange score determination subunit is used to determine the pseudorange residual score corresponding to the ith grid unit based on the receiver clock error of the ith grid unit and the pseudorange of each satellite. The pseudorange of the satellite refers to the distance between the grid unit and the satellite and the distance between the initial positioning position and the satellite.

In some embodiments, the pseudorange score determination subunit is configured to:

According to the receiver clock error and distance difference of the ith grid unit, the pseudorange residual corresponding to the ith grid unit is determined; wherein the distance difference refers to the distance difference between the ith grid unit and the satellite and the distance difference between the initial positioning position and the satellite;

Determine the standard deviation of the pseudorange of each satellite based on the altitude angle and signal quality measurement value of each satellite;

According to the pseudorange residual corresponding to the i-th grid cell and the pseudorange standard deviation of each satellite, the pseudorange residual term of the visible satellite and the pseudorange residual term of the invisible satellite are determined;

The pseudorange residual term of the satellite is obtained based on the pseudorange residual term of the visible satellite and the pseudorange residual term of the invisible satellite. Determine the pseudorange residual score corresponding to the i-th grid cell.

In some embodiments, the reference satellite determination subunit is configured to:

For each visible satellite among the n satellites, a measurement index of the obstruction of each visible satellite to the mobile terminal is determined according to the signal quality measurement value and the altitude angle of each visible satellite at the position of the i-th grid unit;

The visible satellite corresponding to the metric with the largest value among the metric indicators is determined as the reference satellite.

In some embodiments, the measurement information determination module 1320 is further configured to:

For each of the n satellites, when the elevation angle of the satellite is less than the maximum elevation angle of the building, determining that the predicted line-of-sight result of the satellite is a third value, where the third value is used to indicate that the satellite is an invisible satellite for non-line-of-sight communication with the mobile terminal;

When the elevation angle of the satellite is greater than or equal to the maximum elevation angle of the building, the predicted line of sight result of the satellite is determined to be a fourth value, and the fourth value is used to indicate that the satellite is a visible satellite for line-of-sight communication with the mobile terminal.

In some embodiments, the positioning result determination module 1340 is further configured to:

According to the comprehensive scores corresponding to the M grid units, a grid unit corresponding to the comprehensive score that meets the first condition is selected;

Dividing the selected grid unit into at least one connected region, each connected region containing at least one selected grid unit;

The positioning result of the mobile terminal is determined according to the positions and comprehensive scores of the grid cells included in each connected area, and the number of grid cells included in each connected area.

For each connected area, determine the weights of the grid cells included in the connected area according to the comprehensive scores of the grid cells included in the connected area and the maximum and minimum values of the comprehensive scores that meet the first condition;

Determine a probability value of the connected area according to the weights of the grid cells included in the connected area and the number of grid cells included in the connected area, where the probability value of the connected area is used to indicate the probability that the mobile terminal is located in the connected area;

In the connected area with the largest probability value, the positioning result of the mobile terminal is determined based on the proximity algorithm according to the positions of each grid unit in the connected area with the largest probability value and the number of grid units included in the connected area with the largest probability value.

In some embodiments, the apparatus 1300 further includes:

The grid unit generation module is used to generate M grid units with the initial positioning position as the center, wherein the M grid units are arranged in a rows and b columns, and a and b are positive integers.

The technical solution provided in the embodiments of the present application can bring the following beneficial effects:

By utilizing the three-dimensional building information around the initial positioning position of the mobile terminal to determine the line-of-sight or non-line-of-sight state of each satellite for the mobile terminal at different positions, it can be determined that when the mobile terminal is located at different positions in an urban environment, being blocked by surrounding buildings will affect its reception of satellite signals. Therefore, the positioning solution program of the mobile terminal can correct the positioning result according to the interference information of the mobile terminal being blocked by buildings, reduce the positioning error caused by the mobile terminal being blocked by buildings, and improve the precision and accuracy of positioning.

It should be noted that the device provided in the above embodiment, when implementing its functions, is only illustrated by the division of the above functional modules. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the content structure of the device is divided into different functional modules to complete all or part of the functions described above. In addition, the device and method embodiments provided in the above embodiment belong to the same concept, and the specific implementation process is detailed in the method embodiment, which will not be repeated here.

Please refer to Figure 14, which shows a block diagram of a computer device 1400 provided in one embodiment of the present application. The computer device 1400 can be any electronic device with data calculation, processing and storage functions. The computer device 1400 can be used to implement the positioning method of the mobile terminal provided in the above embodiment.

Typically, the computer device 1400 includes a processor 1401 and a memory 1402 .

The processor 1401 may include one or more processing cores, such as a 4-core processor, a 9-core processor, etc. The processor 1401 can be implemented in at least one of the following hardware forms: DSP (Digital Signal Processing), FPGA (Field Programmable Gate Array), and PLA (Programmable Logic Array). The processor 1401 may also include a main processor and a coprocessor. The main processor is a processor for processing data in an awake state, also known as a CPU (Central Processing Unit); the coprocessor is a low-power processor for processing data in a standby state. In some embodiments, the processor 1401 may be integrated with a GPU (Graphics Processing Unit), which is responsible for rendering and drawing the content to be displayed on the display screen. In some embodiments, the processor 1401 may also include an AI processor for processing computing operations related to machine learning.

The memory 1402 may include one or more computer-readable storage media, which may be non-transitory. The memory 1402 may also include a high-speed random access memory and a non-volatile memory, such as one or more disk storage devices and flash memory storage devices. In some embodiments, the non-transitory computer-readable storage medium in the memory 1402 is used to store computer-readable instructions, which are configured to be executed by one or more processors to implement the above-mentioned positioning method of the mobile terminal.

Those skilled in the art will appreciate that the structure shown in FIG. 14 does not limit the computer device 1400 , and may include more or fewer components than shown, or combine certain components, or adopt a different component arrangement.

In an illustrative embodiment, a computer-readable storage medium is also provided, in which computer-readable instructions are stored, and when the computer-readable instructions are executed by a processor of a computer device, the positioning method of the mobile terminal is implemented. Optionally, the computer-readable storage medium can be a ROM (Read-Only Memory), a RAM (Random Access Memory), a CD-ROM (Compact Disc Read-Only Memory), a magnetic tape, a floppy disk, an optical data storage device, etc.

In an exemplary embodiment, a computer program product is also provided, the computer program product includes computer-readable instructions, the computer-readable instructions are stored in a computer-readable storage medium. A processor of a computer device reads the computer-readable instructions from the computer-readable storage medium, and the processor executes the computer-readable instructions, so that the computer device executes the above-mentioned positioning method of a mobile terminal.

It should be noted that the information and data involved in this application (including but not limited to the preliminary positioning location of the mobile terminal, etc.) are obtained with the authorization of the user or with the full authorization of all parties, and the collection, use and processing of relevant information and data must comply with the relevant laws, regulations and standards of the relevant countries and regions.

It should be understood that the "multiple" mentioned in this article refers to two or more. "And/or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and/or B can represent: A exists alone, A and B exist at the same time, and B exists alone. The character "/" generally indicates that the objects associated with each other are in an "or" relationship. In addition, the step numbers described in this article only illustrate a possible execution sequence between the steps. In some other embodiments, the above steps may not be executed in the order of the numbers, such as two steps with different numbers are executed at the same time, or two steps with different numbers are executed in the opposite order to the diagram. The embodiments of the present application are not limited to this.

The technical features of the above embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

A method for positioning a mobile terminal is performed by a computer device, the method comprising:

Acquire a preliminary positioning position of the mobile terminal, determine building data of at least one building around the preliminary positioning position, and satellite position data of satellites around the preliminary positioning position;

For an i-th grid cell among M grid cells located around the preliminary positioning position, determining, according to the building data and the satellite position data, the measured line-of-sight information corresponding to the i-th grid cell, where M is an integer greater than 1, and i is an integer less than or equal to M;

Determine a comprehensive score corresponding to the i-th grid unit according to the measured line-of-sight information corresponding to the i-th grid unit and the satellite signal measurement information corresponding to the i-th grid unit; and

The positioning result of the mobile terminal is determined according to the comprehensive scores respectively corresponding to the M grid units.
According to the method of claim 1, the building data includes the location and spatial information of the building, and the satellite position data includes the position coordinates of n satellites around the preliminary positioning position, where n is a positive integer.
According to the method according to claim 1 or 2, the measured line-of-sight information corresponding to the i-th grid unit includes the measured line-of-sight results of each of the satellites, and the measured line-of-sight results are the results of determining whether there is line-of-sight communication between the satellite and the mobile terminal when the mobile terminal is located in the i-th grid unit according to the obstruction of the building. When there is line-of-sight communication between the satellite and the mobile terminal located in the i-th grid unit, the i-th grid unit can receive the satellite signal sent by the satellite without obstruction.
According to the method described in any one of claims 1 to 3, the satellite signal measurement information corresponding to the i-th grid unit includes the signal quality measurement values of each of the satellites at the position of the i-th grid unit, and the comprehensive score corresponding to the i-th grid unit is used to indicate the probability that the mobile terminal is located in the i-th grid unit.
According to the method according to any one of claims 1 to 4, determining the comprehensive score corresponding to the i-th grid unit according to the measured line of sight information corresponding to the i-th grid unit and the satellite signal measurement information corresponding to the i-th grid unit comprises:

Determine a line of sight matching score corresponding to the ith grid unit according to the measured line of sight information corresponding to the ith grid unit and the satellite signal measurement information corresponding to the ith grid unit, wherein the line of sight matching score corresponding to the ith grid unit is used to indicate the similarity between the measured line of sight information corresponding to the ith grid unit and the predicted line of sight information corresponding to the ith grid unit;

Determine, according to the measured line-of-sight information corresponding to the i-th grid unit and the satellite signal measurement information corresponding to the i-th grid unit, a pseudorange residual score corresponding to the i-th grid unit, wherein the pseudorange residual score corresponding to the i-th grid unit is used to indicate a comprehensive pseudorange residual of a pseudorange residual of a visible satellite and a pseudorange residual of an invisible satellite;

A comprehensive score corresponding to the i-th grid unit is determined according to the line-of-sight matching score corresponding to the i-th grid unit and the pseudorange residual score corresponding to the i-th grid unit.
According to the method of claim 5, determining the line-of-sight matching score corresponding to the i-th grid unit according to the measured line-of-sight information corresponding to the i-th grid unit and the satellite signal measurement information corresponding to the i-th grid unit comprises:

Determine, according to the satellite signal measurement information corresponding to the i-th grid unit, the predicted line-of-sight information corresponding to the i-th grid unit, wherein the predicted line-of-sight information corresponding to the i-th grid unit includes the predicted line-of-sight results of each of the satellites, and the predicted line-of-sight result refers to a result of whether line-of-sight communication is achieved between the satellite and the mobile terminal, assuming that the mobile terminal is located in the i-th grid unit and is predicted according to the signal quality measurement value of the satellite;

A sight distance matching score corresponding to the i-th grid unit is determined according to a similarity between the measured sight distance information corresponding to the i-th grid unit and the predicted sight distance information corresponding to the i-th grid unit.
According to the method of claim 6, determining the predicted line of sight information corresponding to the i-th grid unit according to the satellite signal measurement information corresponding to the i-th grid unit comprises:

For each of the n satellites, when the signal quality measurement value of the satellite is less than a minimum threshold value, determining that the predicted line of sight result of the satellite is a first value, wherein the first value is used to indicate whether the satellite is Invisible satellites for non-line-of-sight communications between mobile terminals;

When the signal quality measurement value of the satellite is greater than a maximum threshold value, determining that the predicted line-of-sight result of the satellite is a second value, where the second value is used to indicate that the satellite is a visible satellite for line-of-sight communication with the mobile terminal;

When the signal quality measurement value of the satellite is greater than the minimum threshold value and less than the maximum threshold value, a value of a predicted line-of-sight result of the satellite is determined based on a linear regression fitting algorithm according to the signal quality measurement value of the satellite.
According to the method of claim 6, the similarity between the measured sight distance information corresponding to the i-th grid unit and the predicted sight distance information corresponding to the i-th grid unit comprises:

Calculating the mean of the measured sight distance results of each of the satellites included in the measured sight distance information corresponding to the i-th grid unit to obtain a first mean value, and calculating the mean of the predicted sight distance results of each of the satellites included in the predicted sight distance information corresponding to the i-th grid unit to obtain a second mean value;

Calculating the standard deviation of the measured sight-range results of each of the satellites included in the measured sight-range information corresponding to the i-th grid unit to obtain a first standard deviation, and calculating the standard deviation of the predicted sight-range results of each of the satellites included in the predicted sight-range information corresponding to the i-th grid unit to obtain a second standard deviation;

Calculating a first similarity parameter according to the first mean and the second mean;

Calculating a second similarity parameter according to the first standard deviation and the second standard deviation;

Calculate a third similarity parameter according to the first standard deviation, the second standard deviation, and the covariance of the first mean and the second mean;

The similarity between the measured viewing distance information corresponding to the i-th grid unit and the predicted viewing distance information corresponding to the i-th grid unit is calculated according to the first similarity parameter, the second similarity parameter and the third similarity parameter.
According to the method according to any one of claims 5 to 8, determining the pseudorange residual score corresponding to the i-th grid unit according to the measured line of sight information corresponding to the i-th grid unit and the satellite signal measurement information corresponding to the i-th grid unit, comprises:

Determine a reference satellite from the n satellites according to the signal quality measurement values and altitude angles of each of the satellites at the position of the i-th grid unit, wherein the reference satellite refers to a visible satellite with the lowest probability of being blocked for the mobile terminal among the n satellites;

Determine the receiver clock error of the i-th grid unit according to the distance between the i-th grid unit and the reference satellite, and the distance between the preliminary positioning position and the reference satellite;

The pseudorange residual score corresponding to the i-th grid unit is determined based on the receiver clock error of the i-th grid unit and the pseudorange of each of the satellites, wherein the pseudorange of the satellite includes the distance between the grid unit and the satellite and the distance between the preliminary positioning position and the satellite.
According to the method of claim 9, determining the pseudorange residual score corresponding to the i-th grid unit according to the receiver clock error of the i-th grid unit and the pseudorange of each of the satellites, comprises:

Determine the pseudorange residual corresponding to the i-th grid unit according to the receiver clock error and the distance difference of the i-th grid unit; wherein the distance difference refers to the difference between the distance between the i-th grid unit and the satellite and the distance between the preliminary positioning position and the satellite;

Determining a pseudorange standard deviation of each of the satellites based on the altitude angle and signal quality measurement value of each of the satellites;

Determining a pseudorange residual term of a visible satellite and a pseudorange residual term of an invisible satellite according to the pseudorange residual corresponding to the i-th grid unit and a pseudorange standard deviation of each of the satellites;

The pseudorange residual score corresponding to the i-th grid unit is determined according to the pseudorange residual item of the satellite obtained by the pseudorange residual item of the visible satellite and the pseudorange residual item of the invisible satellite.
According to the method of claim 9 or 10, determining a reference satellite from the n satellites based on the signal quality measurement values and elevation angles of each of the satellites at the position of the i-th grid unit comprises:

For each visible satellite among the n satellites, the obstruction of each visible satellite for the mobile terminal is determined according to the signal quality measurement value and the altitude angle of each visible satellite at the position of the i-th grid unit. Measuring indicators of the blocking situation;

The visible satellite corresponding to the metric with the largest value among the metric indicators is determined as the reference satellite.
According to the method according to any one of claims 1 to 11, determining the measured line of sight information corresponding to the i-th grid unit according to the building data and the satellite position data comprises:

For each of the n satellites, when the altitude angle of the satellite is less than the maximum altitude angle of the building, determining that the predicted line of sight result of the satellite is a third value, wherein the third value is used to indicate that the satellite is an invisible satellite for non-line-of-sight communication with the mobile terminal;

When the altitude angle of the satellite is greater than or equal to the maximum altitude angle of the building, the predicted line of sight result of the satellite is determined to be a fourth value, and the fourth value is used to indicate that the satellite is a visible satellite for line-of-sight communication with the mobile terminal.
According to the method according to any one of claims 1 to 12, determining the positioning result of the mobile terminal according to the comprehensive scores respectively corresponding to the M grid units comprises:

According to the comprehensive scores respectively corresponding to the M grid units, a grid unit corresponding to the comprehensive score that meets the first condition is selected;

Dividing the selected grid unit into at least one connected area, each of the connected areas contains at least one selected grid unit;

The positioning result of the mobile terminal is determined according to the positions and comprehensive scores of the grid units included in each of the connected areas, and the number of the grid units included in each of the connected areas.
According to the method of claim 13, determining the positioning result of the mobile terminal according to the positions and comprehensive scores of the grid cells contained in each of the connected areas, and the number of grid cells contained in each of the connected areas, comprises:

For each connected area, determine the weights of the grid cells included in the connected area according to the comprehensive scores of the grid cells included in the connected area and the maximum and minimum values of the comprehensive scores that meet the first condition;

Determine a probability value of the connected area according to the weights of the grid cells included in the connected area and the number of grid cells included in the connected area, wherein the probability value of the connected area is used to indicate the probability that the mobile terminal is located in the connected area;

In the connected area with the maximum probability value, the positioning result of the mobile terminal is determined based on a proximity algorithm according to the positions of each grid unit in the connected area with the maximum probability value and the number of grid units included in the connected area with the maximum probability value.
The method according to any one of claims 1 to 14, further comprising:

The M grid units are generated with the preliminary positioning position as the center, wherein the M grid units are arranged in a rows and b columns, and a and b are positive integers.
According to the method described in any one of claims 1 to 15, for the grid cells located outside the building among the M grid cells, the corresponding comprehensive scores are determined, and for the grid cells located inside the building among the M grid cells, the corresponding comprehensive scores are not determined.
A positioning device for a mobile terminal, the device comprising:

A data acquisition module, used to acquire a preliminary positioning position of the mobile terminal, determine building data of at least one building around the preliminary positioning position, and satellite position data of satellites around the preliminary positioning position;

a measurement information determination module, configured to determine, for an i-th grid cell among M grid cells located around the preliminary positioning position, measurement line of sight information corresponding to the i-th grid cell according to the building data and the satellite position data, where M is an integer greater than 1 and i is an integer less than or equal to M;

a comprehensive score determination module, configured to determine a comprehensive score corresponding to the ith grid unit according to the measured line-of-sight information corresponding to the ith grid unit and the satellite signal measurement information corresponding to the ith grid unit; and

The positioning result determination module is used to determine the positioning result of the mobile terminal according to the comprehensive scores corresponding to the M grid units respectively.
A computer device comprises a processor and a memory, wherein the memory stores computer-readable instructions, and the computer-readable instructions are loaded and executed by the processor to implement the positioning method of a mobile terminal as described in any one of claims 1 to 16.
A computer-readable storage medium, wherein the computer-readable storage medium stores computer-readable instructions, wherein the computer-readable instructions are loaded and executed by a processor to implement the positioning method for a mobile terminal as described in any one of claims 1 to 16.
A computer program product, comprising computer-readable instructions, wherein the computer-readable instructions are loaded and executed by a processor to implement the positioning method for a mobile terminal as claimed in any one of claims 1 to 16.