A method, apparatus, device, and storage medium for determining the position of a terminal

Abstract

Embodiments of the present application disclose a method, apparatus, device, and storage medium for determining the position of a terminal. Related embodiments can be applied to various scenarios such as intelligent transportation, cloud technology, artificial intelligence, maps, and autonomous driving to improve the accuracy of obtaining the positioning position of the terminal. The method includes: obtaining elevation information corresponding to the approximate position of the terminal and Doppler observations of each satellite, calculating a parameter matrix of the elevation information with respect to the terminal position to be solved and a first residual through an elevation constraint equation, calculating a first Jacobian matrix of the Doppler observations with respect to the terminal position to be solved and the receiver clock drift and a second residual through a Doppler observation equation, calculating a correction amount of the estimated parameters based on the parameter matrix, the first residual, the first Jacobian matrix, and the second residual, where the estimated parameters include the terminal position to be solved and the receiver clock drift, and when the correction amount meets the iteration end condition, determining the target terminal position according to the terminal position to be solved and the receiver clock drift.

Description

[0001] This application claims the priority of a Chinese patent application titled "A Method, Apparatus, Device, and Storage Medium for Determining the Position of a Terminal" with an application number of 202210542502.1 and filed with the Chinese Patent Office on May 18, 2022, the entire content of which is incorporated herein by reference. Technical Field

[0002] Embodiments of this application relate to the technical field of satellite navigation signal processing, and particularly to a method, apparatus, device, and storage medium for determining the position of a terminal. Background Art

[0003] The Global Navigation Satellite System (GNSS) is a space-based radio navigation and positioning system that can provide users with all-weather three-dimensional coordinates, speed, and time information at any location on the Earth's surface or in near-Earth space. Common systems include the Global Positioning System (GPS), the BeiDou Navigation Satellite System (BDS), the Global Navigation Satellite System (GLONASS), and the Galileo Positioning System (GALILEO).

[0004] The Time To First Fix (TTFF) is the time required for a GNSS receiver to obtain a position solution and is an important parameter for measuring the positioning ability of the system. Since any delay will affect the user's experience, one of the important tasks of the global navigation satellite system is to accelerate the TTFF.

[0005] Currently, the improvement of the TTFF generally involves predicting the current position of GPS satellites based on historical GPS satellite position information, and identifying and locking a predetermined number of visible satellites based on the predicted GPS satellite positions to accelerate the GNSS TTFF. Alternatively, existing radiolocation opportunity signals such as Amplitude Modulation (AM) or Frequency Modulation (FM) radio signals and television signals are used to determine the approximate location of the receiver, and then the almanac and battery backup date and time are used to determine the visible satellites and narrow the Doppler frequency range to accelerate the GNSS TTFF.

[0006] However, these methods generally require capturing signals from at least four GNSS satellites for positioning calculation. When the number of satellites is less than 4 or the ephemeris data is insufficient, positioning calculation cannot be performed, resulting in a decrease in the position accuracy of the positioning terminal. Summary of the Invention

[0007] Embodiments of the present application provide a method, device, equipment, and storage medium for determining the terminal position. By jointly calculating the correction amount of the estimation parameters through the elevation constraint equation and the Doppler observation equation, the estimation parameters are continuously iteratively optimized to assist the terminal satellite positioning, enhance the availability of satellite positioning in weak satellite signal scenarios such as insufficient ephemeris data or a small number of effective satellites, and achieve the positioning calculation of the terminal position, thereby improving the accuracy of the positioning terminal position.

[0008] On the one hand, embodiments of the present application provide a method for determining the terminal position, including:

[0009] Obtain the elevation information corresponding to the approximate position of the terminal and the Doppler observation value of each satellite;

[0010] Calculate the parameter matrix of the elevation information with respect to the terminal position to be solved and the first residual through the elevation constraint equation;

[0011] Calculate the first Jacobian matrix and the second residual of the Doppler observation value with respect to the terminal position to be solved and the receiver clock drift through the Doppler observation equation;

[0012] Calculate the correction amount of the estimation parameter based on the parameter matrix, the first residual, the first Jacobian matrix, and the second residual, where the estimation parameter includes the terminal position to be solved and the receiver clock drift;

[0013] When the correction amount meets the iteration end condition, determine the target terminal position according to the terminal position to be solved and the receiver clock drift.

[0014] On the other hand, embodiments of the present application provide a device for determining the terminal position, including:

[0015] An acquisition unit, configured to obtain the elevation information corresponding to the approximate position of the terminal and the Doppler observation value of each satellite;

[0016] A processing unit, configured to calculate the parameter matrix of the elevation information with respect to the terminal position to be solved and the first residual through the elevation constraint equation;

[0017] The processing unit is further configured to calculate the first Jacobian matrix and the second residual of the Doppler observation value with respect to the terminal position to be solved and the receiver clock drift through the Doppler observation equation;

[0018] The processing unit is further configured to calculate a correction amount of the estimated parameters based on the parameter matrix, the first residual, the first Jacobian matrix, and the second residual, where the estimated parameters include the terminal position to be solved and the receiver clock drift;

[0019] The determination unit is configured to determine the target terminal position according to the terminal position to be solved and the receiver clock drift when the correction amount meets the iteration end condition.

[0020] In a possible design, in an implementation manner of another aspect of the embodiments of the present application,

[0021] The processing unit may specifically be configured to: calculate a correction amount of the estimated parameters based on the parameter matrix, the first residual, the first Jacobian matrix, the second residual, the second Jacobian matrix, and the third residual;

[0022] The determination unit may specifically be configured to: determine the target terminal position according to the terminal position to be solved, the receiver clock drift, the receiver clock error, and the deviation value between the standard time and the current moment of the terminal when the correction amount meets the iteration end condition.

[0023] In a possible design, in an implementation manner of another aspect of the embodiments of the present application,

[0024] The acquisition unit is further configured to acquire the pseudorange observation value of each satellite and the standard time;

[0025] The processing unit is further configured to calculate the second Jacobian matrix and the third residual of the pseudorange observation value and the standard time with respect to the terminal position to be solved, the receiver clock error, the deviation value between the standard time and the current moment of the terminal, and the time system deviation through the pseudorange observation equation.

[0026] In a possible design, in an implementation manner of another aspect of the embodiments of the present application,

[0027] The processing unit is further configured to calculate a weight matrix based on the elevation angle of each satellite and the signal-to-noise ratio of the pseudorange observation value;

[0028] The processing unit may specifically be configured to: calculate the partial derivative of the estimated parameters based on the parameter matrix, the first Jacobian matrix, and the second Jacobian matrix;

[0029] Calculate the correction amount of the estimated parameters based on the partial derivative, the weight matrix, the first residual, the second residual, and the third residual.

[0030] In a possible design, in an implementation manner of another aspect of the embodiments of the present application, the processing unit may specifically be configured to:

[0031] Construct a mathematical model of the pseudorange observation value based on the terminal position to be solved, the receiver clock error, the deviation value between the standard time and the current moment of the terminal, the error correction number, and the speed of light value in vacuum;

[0032] Construct a pseudorange observation equation for N satellites based on the mathematical model of pseudorange observations, where N is an integer greater than or equal to 1.

[0033] In a possible design, in an implementation of another aspect of the embodiments of the present application, the processing unit may specifically be used for:

[0034] Calculate the pseudorange observation matrix based on the pseudorange observation equation for the pseudorange observations;

[0035] Derive the second Jacobian matrix for the to-be-solved terminal position, receiver clock offset, deviation value between the standard time and the current time of the terminal, and time system deviation based on the pseudorange observation matrix;

[0036] Determine the third residual based on the pseudorange observations and the estimated value of the pseudorange observation matrix.

[0037] In a possible design, in an implementation of another aspect of the embodiments of the present application, the processing unit may specifically be used for:

[0038] Optimize the mathematical model of the pseudorange observations based on the external time deviation to obtain the mathematical optimization model of the pseudorange observations;

[0039] Construct a terminal time deviation correction equation for N satellites based on the mathematical optimization model of the pseudorange observations;

[0040] The processing unit may specifically be used for: calculating the second Jacobian matrix and the third residual of the pseudorange observations and the standard time with respect to the to-be-solved terminal position, the receiver clock offset, the deviation value between the standard time and the current time of the terminal, and the time system deviation through the terminal time deviation correction equation.

[0041] In a possible design, in an implementation of another aspect of the embodiments of the present application, the processing unit may specifically be used for:

[0042] Construct a constraint condition between the terminal geodetic coordinates and the to-be-solved terminal position, the prior error of the terminal geodetic coordinates, and the prior error of the to-be-solved terminal position based on the elevation prior information;

[0043] Perform a Taylor series expansion on the prior error of the to-be-solved terminal position based on the constraint condition and the prior error of the terminal geodetic coordinates;

[0044] Arrange the Taylor series expansion to obtain an elevation constraint equation.

[0045] In a possible design, in an implementation of another aspect of the embodiments of the present application, the processing unit may specifically be used for:

[0046] Calculate the elevation information based on the elevation constraint equation to obtain an elevation prediction matrix;

[0047] Derive the parameter matrix by taking the derivative of the terminal position to be solved based on the elevation prediction matrix;

[0048] Determine the first residual based on the elevation information and the estimated value of the elevation prediction matrix.

[0049] In a possible design, in an implementation manner on the other hand of the embodiment of the present application, the processing unit may specifically be used for:

[0050] Construct a mathematical model of the Doppler observation value based on the terminal position to be solved, the receiver clock drift, the wavelength of the satellite broadcast signal, and the speed of light value in vacuum;

[0051] Construct Doppler observation equations for N satellites based on the mathematical model of the Doppler measurement value.

[0052] In a possible design, in an implementation manner on the other hand of the embodiment of the present application, the processing unit may specifically be used for:

[0053] Calculate the Doppler observation value based on the Doppler observation equation to obtain a Doppler observation matrix;

[0054] Derive the first Jacobian matrix by taking the derivative of the terminal position to be solved and the receiver clock drift based on the Doppler observation matrix;

[0055] Determine the second residual based on the Doppler observation value and the estimated value of the Doppler observation matrix.

[0056] In a possible design, in an implementation manner on the other hand of the embodiment of the present application, the processing unit may specifically be used for:

[0057] When the modulus of the correction amount is less than the correction threshold, determine the target estimation parameter;

[0058] Solve the terminal position to be solved based on the receiver clock drift, receiver clock error, and the deviation value between the standard time and the current time of the terminal in the target estimation parameter to obtain the target terminal position.

[0059] In a possible design, in an implementation manner on the other hand of the embodiment of the present application, the acquisition unit may specifically be used for:

[0060] Send an elevation information acquisition request carrying the approximate position of the terminal to the regional elevation database server, so that the regional elevation database server collects the elevation information corresponding to the approximate position of the terminal according to the elevation information acquisition request;

[0061] Receive the elevation information broadcast by the regional elevation database server;

[0062] Send a satellite navigation ephemeris request to a continuously operating reference station CORS server so that the CORS server queries ephemeris data according to the satellite navigation ephemeris request;

[0063] Receive the full-system ephemeris data sent by the CORS server;

[0064] Extract Doppler observations from the full-system ephemeris data;

[0065] The obtaining unit can specifically be used to: extract pseudorange observations corresponding to the approximate position of the terminal from the full-system ephemeris data and obtain the standard time.

[0066] In a possible design, in an implementation manner of another aspect of this application, the obtaining unit can specifically be used to:

[0067] Send a timing request to a timing system server so that the timing system server queries the standard time according to the timing request;

[0068] Receive the standard time sent by the timing system server.

[0069] This application further provides a computer device, including: a memory, a processor, and a bus system;

[0070] Among them, the memory is used to store programs;

[0071] The processor is used to implement the methods in the above aspects when executing the programs in the memory;

[0072] The bus system is used to connect the memory and the processor so that the memory and the processor can communicate.

[0073] This application further provides a computer-readable storage medium. Instructions are stored in the computer-readable storage medium. When it runs on a computer, it causes the computer to execute the methods in the above aspects.

[0074] From the above technical solutions, it can be seen that the embodiments of this application have the following beneficial effects:

[0075] By obtaining the elevation information corresponding to the approximate position of the terminal and the Doppler observations of each satellite, the parameter matrix of the elevation information with respect to the terminal position to be solved and the first residual can be calculated through the elevation constraint equation, and the first Jacobian matrix of the Doppler observations with respect to the terminal position to be solved and the receiver clock drift and the second residual can be calculated through the Doppler observation equation. Then, based on the parameter matrix, the first residual, the first Jacobian matrix, and the second residual, the correction amount of the estimated parameter is calculated. Then, if the correction amount satisfies the iteration end condition, the target estimated parameter corresponding to the correction amount and the target terminal position corresponding to the target estimated parameter are determined. Through the above method, by constructing the elevation constraint equation and the Doppler observation equation in the weak satellite signal scenario, and constructing the estimated parameter with respect to the terminal position, and based on the obtained elevation information and Doppler observations, the correction amount of the estimated parameter is jointly calculated through the elevation constraint equation and the Doppler observation equation to continuously iteratively optimize the estimated parameter to determine the target terminal position. It is possible to jointly calculate and iteratively optimize the estimated parameter through the elevation constraint equation and the Doppler observation equation to assist the terminal satellite positioning, enhance the availability of satellite positioning in weak satellite signal scenarios such as insufficient ephemeris data or a small number of effective satellites, and realize the positioning solution of the terminal position, thereby improving the accuracy of the positioned terminal position. BRIEF DESCRIPTION OF THE DRAWINGS

[0076] FIG. 1(a) is a schematic diagram of the architecture of the positioning control system in an embodiment of the present application;

[0077] FIG. 1(b) is an interaction schematic diagram of the positioning control system in an embodiment of the present application;

[0078] FIG. 1(c) is another interaction schematic diagram of the positioning control system in an embodiment of the present application;

[0079] FIG. 1(d) is another interaction schematic diagram of the positioning control system in an embodiment of the present application;

[0080] Figure 2 is a flowchart of an embodiment of the method for determining the terminal position in an embodiment of the present application;

[0081] Figure 3 is a flowchart of another embodiment of the method for determining the terminal position in an embodiment of the present application;

[0082] Figure 4 is a flowchart of another embodiment of the method for determining the terminal position in an embodiment of the present application;

[0083] Figure 5 is a flowchart of another embodiment of the method for determining the terminal position in an embodiment of the present application;

[0084] Figure 6It is another flowchart of the method for determining the terminal position in the embodiment of the present application;

[0085] Figure 7 It is another flowchart of the method for determining the terminal position in the embodiment of the present application;

[0086] Figure 8 It is another flowchart of the method for determining the terminal position in the embodiment of the present application;

[0087] Figure 9 It is another flowchart of the method for determining the terminal position in the embodiment of the present application;

[0088] Figure 10 It is another flowchart of the method for determining the terminal position in the embodiment of the present application;

[0089] Figure 11 It is another flowchart of the method for determining the terminal position in the embodiment of the present application;

[0090] Figure 12 It is another flowchart of the method for determining the terminal position in the embodiment of the present application;

[0091] Figure 13 It is another flowchart of the method for determining the terminal position in the embodiment of the present application;

[0092] Figure 14 It is another flowchart of the method for determining the terminal position in the embodiment of the present application;

[0093] Figure 15 It is a schematic diagram of the principle process of the method for determining the terminal position in the embodiment of the present application;

[0094] Figure 16 It is another schematic diagram of the principle process of the method for determining the terminal position in the embodiment of the present application;

[0095] Figure 17 It is a schematic diagram of obtaining the estimated parameters of the method for determining the terminal position in the embodiment of the present application;

[0096] Figure 18 It is a schematic diagram of constructing the elevation constraint equation of the method for determining the terminal position in the embodiment of the present application;

[0097] Figure 19 It is a schematic diagram of positioning and solving based on the terminal time deviation correction equation of the method for determining the terminal position in the embodiment of the present application;

[0098] Figure 20 It is a schematic diagram of an embodiment of the device for determining the terminal position in the embodiment of the present application;

[0099] Figure 21 This is a schematic diagram of an embodiment of a computer device in an embodiment of the present application. Detailed implementation manners

[0100] The embodiments of the present application provide a method, apparatus, device, and storage medium for determining the position of a terminal. It is used to jointly calculate the correction amount of the estimation parameter through the elevation constraint equation and the Doppler observation equation, and continuously iteratively optimize the estimation parameter to assist the terminal satellite positioning, enhance the availability of satellite positioning in weak satellite signal scenarios such as insufficient ephemeris data or a small number of effective satellites, and realize the positioning solution of the terminal position, thereby improving the accuracy of positioning the terminal position.

[0101] The terms "first", "second", "third", "fourth", etc. (if any) in the specification, claims, and drawings of the present application are used to distinguish similar objects, and do not necessarily describe a specific order or sequence. It should be understood that such used data can be interchanged under appropriate circumstances so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "corresponding to" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products, or devices.

[0102] 1. Global Navigation Satellite System

[0103] The Global Navigation Satellite System (GNSS) is a space-based radio navigation and positioning system that can provide users with all-weather three-dimensional coordinates, speed, and time information at any location on the Earth's surface or in near-Earth space. The GNSS is applied in aspects such as navigation, communication, consumer entertainment, surveying and mapping, timekeeping, vehicle management, automotive navigation, and information services, and is used to provide high-precision services for applications in real time.

[0104] 2. Terminal Satellite Positioning Device

[0105] A terminal satellite positioning device is an electronic device used to process satellite signals and measure the geometric distance (pseudorange observation value) between the device and the satellite as well as the Doppler effect of the satellite signal (i.e., the pseudorange rate observation value); a satellite positioning device usually includes modules such as an antenna, a satellite signal operation loop, and baseband signal processing. A mobile terminal integrating the satellite positioning device calculates the current position coordinates of the mobile terminal based on the pseudorange and pseudorange rate observation values. The satellite positioning device is widely used in fields such as navigation, surveying and mapping, or location services, such as smartphone map navigation or high-precision geodetic surveying.

[0106] 3. Terminal Device

[0107] The terminal device can specifically be manifested as a mobile terminal, that is, a mobile communication terminal, which refers to a computer device that can be used while moving, including but not limited to mobile phones, laptops, tablets, POS machines, in-vehicle computers, etc., and is commonly found in mobile phones or smartphones with multiple application functions and tablets. The mobile terminal can communicate through wireless operating networks such as Global System for Mobile Communication (GSM), Code Division Multiple Access (CDMA), Wideband Code Division Multiple Access (WCDMA), Enhanced Data Rate for GSM Evolution (EDGE), or 4G, and can also communicate through wireless local area networks, Bluetooth, or infrared rays. In addition, the mobile terminal includes a satellite positioning device, and the mobile terminal integrates a global satellite navigation system positioning chip, which can be used to process satellite signals and position location.

[0108] 4. CORS System

[0109] The CORS system is the product of the multi-faceted and in-depth crystallization of high-tech such as satellite positioning technology, computer network technology, and digital communication technology. The CORS system consists of five parts: a reference station network, a data processing center, a data transmission system, a positioning and navigation data broadcast system, and a user application system. Each reference station is connected to the analysis center through the data transmission system to form a dedicated network.

[0110] It can be understood that in the specific implementation manner of this application, it involves relevant data such as first-time data and second-time data. When the above embodiments of this application are applied to specific products or technologies, user permission or consent is required, and the collection, use, and processing of relevant data need to comply with the relevant laws, regulations, and standards of relevant countries and regions.

[0111] It can be understood that the method for determining the terminal position disclosed in the present application is specifically related to the Intelligent Vehicle Infrastructure Cooperative Systems (IVICS). The Intelligent Vehicle Infrastructure Cooperative Systems, abbreviated as the vehicle-road collaborative system, is a development direction of the Intelligent Transportation System (ITS). The vehicle-road collaborative system adopts advanced wireless communication and new-generation Internet technologies to comprehensively implement dynamic real-time information interaction between vehicles and between vehicles and roads. Based on the collection and fusion of dynamic traffic information in the whole time and space, it conducts active safety control of vehicles and collaborative management of roads, fully realizes the effective collaboration of people, vehicles and roads, ensures traffic safety, improves traffic efficiency, and thus forms a safe, efficient and environmentally friendly road traffic system.

[0112] It can be understood that the method for determining the terminal position disclosed in the present application is also related to cloud technology. The following further introduces cloud technology. Cloud technology refers to a hosting technology that unifies a series of resources such as hardware, software, and networks within a wide area network or a local area network to achieve the calculation, storage, processing, and sharing of data. Cloud technology is the general term for network technology, information technology, integration technology, management platform technology, application technology, etc. based on the cloud computing business model, which can form a resource pool, be used on demand, and be flexible and convenient. Cloud computing technology will become an important support. The background services of the technical network system require a large amount of computing and storage resources, such as video websites, picture websites, and more portal websites. With the high development and application of the Internet industry, in the future, each item may have its own identification mark and needs to be transmitted to the background system for logical processing. Data at different levels will be processed separately, and various types of industry data require a powerful system back-end support, which can only be achieved through cloud computing.

[0113] Cloud computing is a computing model that distributes computing tasks on a resource pool composed of a large number of computing devices, enabling various application systems to obtain computing power, storage space, and information services as needed. The network that provides resources is called the "cloud". The resources in the "cloud" seem to be infinitely expandable to users, and can be obtained at any time, used on demand, expanded at any time, and paid according to usage.

[0114] As a basic capacity provider of cloud computing, a cloud computing resource pool (abbreviated as a cloud platform, generally called an IaaS (Infrastructure as a Service) platform) will be established, and various types of virtual resources will be deployed in the resource pool for external customers to select and use. The cloud computing resource pool mainly includes: computing devices (virtual machines, including operating systems), storage devices, and network devices.

[0115] According to the logical function division, on the IaaS (Infrastructure as a Service) layer, the PaaS (Platform as a Service) layer can be deployed, and on top of the PaaS layer, the SaaS (Software as a Service) layer can be deployed. Or the SaaS can be directly deployed on the IaaS. PaaS is the platform for software operation, such as databases, web containers, etc. SaaS is various transaction software, such as web portals, mass SMS senders, etc. Generally speaking, SaaS and PaaS are the upper layers relative to IaaS.

[0116] Secondly, Cloud Security refers to the general term for security software, hardware, users, organizations, and security cloud platforms based on the cloud computing business model. Cloud Security integrates emerging technologies and concepts such as parallel processing, grid computing, and unknown virus behavior judgment. Through the abnormal monitoring of software behavior in the network by a large number of mesh clients, the latest information about Trojans and malicious programs on the Internet is obtained and sent to the server for automatic analysis and processing. Then, the solutions for viruses and Trojans are distributed to each client.

[0117] Secondly, cloud storage is a new concept extended and developed from the cloud computing concept. A distributed cloud storage system (hereinafter referred to as the storage system) refers to a storage system that, through functions such as cluster applications, grid technology, and distributed storage file systems, aggregates a large number of various types of storage devices (storage devices are also called storage nodes) in the network through application software or application interfaces to work together and jointly provide data storage and transaction access functions to the outside world.

[0118] Currently, the storage method of the storage system is as follows: Create logical volumes. When creating logical volumes, physical storage space is allocated for each logical volume. This physical storage space may be composed of the disks of a certain storage device or several storage devices. The client stores data on a certain logical volume, that is, stores the data on the file system. The file system divides the data into many parts, and each part is an object. The object not only contains the data but also contains additional information such as data identification (ID, ID entity). The file system writes each object into the physical storage space of the logical volume respectively, and the file system will record the storage location information of each object. Thus, when the client requests to access the data, the file system can enable the client to access the data according to the storage location information of each object.

[0119] The process of the storage system allocating physical storage space to a logical volume is specifically as follows: According to the capacity estimation of the objects stored in the logical volume (this estimation often has a large margin relative to the actual capacity of the objects to be stored) and the group of the redundant array of independent disks (RAID), the physical storage space is pre-divided into stripes, and a logical volume can be understood as a stripe, thereby allocating physical storage space to the logical volume.

[0120] It should be understood that the method for determining the terminal position provided in this application can be applied to various scenarios, including but not limited to cloud technology, artificial intelligence, intelligent transportation, assisted driving, etc., for scenarios such as completing the positioning and calculation of the terminal position by obtaining the signals or ephemeris data of GNSS satellites. As an example, for example, the position of mobile phone A is located by obtaining the signals of GNSS satellites. As another example, for example, the in-vehicle computer of vehicle B is located by obtaining the signals and ephemeris data of GNSS satellites to assist in driving vehicle B. In the above various scenarios, in order to complete the positioning of the terminal position, it is usually necessary to capture the signals from at least four GNSS satellites to perform positioning calculation. However, when the number of satellites is less than 4 or the ephemeris data is insufficient, positioning calculation cannot be performed, resulting in a decrease in the accuracy of the positioning terminal position.

[0121] To solve the above problems, this application proposes a method for determining the terminal position. This method is applied to the positioning control system shown in Fig. 1(a). Please refer to Fig. 1(a). Fig. 1(a) is a schematic architecture diagram of the positioning control system in an embodiment of this application. As shown in Fig. 1(a), the terminal device can calculate the parameter matrix and the first residual of the elevation information with respect to the terminal position to be solved through the elevation constraint equation, and calculate the first Jacobian matrix and the second residual of the Doppler observation value with respect to the terminal position to be solved and the receiver clock drift through the Doppler observation equation by obtaining the elevation information corresponding to the approximate position of the terminal sent by the regional elevation database server and the Doppler observation value of each satellite sent by the CORS server, and calculate the correction amount of the estimated parameter based on the parameter matrix, the first residual, the first Jacobian matrix, and the second residual. Then, if the correction amount satisfies the iteration end condition, the target estimated parameter corresponding to the correction amount and the target terminal position corresponding to the target estimated parameter are determined. In the above manner, by constructing the elevation constraint equation and the Doppler observation equation in the weak satellite signal scenario, and constructing the estimated parameter regarding the terminal position, and based on the obtained elevation information and Doppler observation value, the correction amount of the estimated parameter is jointly calculated through the elevation constraint equation and the Doppler observation equation to continuously iteratively optimize the estimated parameter to determine the target terminal position, and the positioning calculation of the terminal position can be realized through the joint calculation of the elevation constraint equation and the Doppler observation equation and the iterative optimization of the estimated parameter, thereby improving the accuracy of the positioning terminal.

[0122] Among them, the regional elevation database server is communicatively connected to the terminal device, the CORS server is communicatively connected to the terminal device, and the timing system server is communicatively connected to the terminal device.

[0123] It can be understood that only one type of terminal device is shown in Fig. 1(a). In actual scenarios, more types of terminal devices can participate in the data processing process. Terminal devices include, but are not limited to, mobile phones, computers, intelligent voice interaction devices, smart home appliances, vehicle-mounted terminals, aircraft, etc. The specific quantity and types depend on the actual scenario and are not limited here specifically. Additionally, servers are shown in Fig. 1(a). It should be understood that the regional elevation database server, CORS server, and timing system server shown in Fig. 1(a) are only examples and do not limit the quantity of the regional elevation database server, CORS server, and timing system server. In actual scenarios, multiple servers can also participate. Especially in the scenario of multi-model training interaction, the quantity of servers depends on the actual scenario and is not limited here specifically.

[0124] It should be noted that in this embodiment, the server can be an independent physical server, or a server cluster or distributed system composed of multiple physical servers, or a cloud server that provides basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communications, middleware services, domain name services, security services, content delivery network (CDN), and big data and artificial intelligence platforms. The terminal device and the server can be directly or indirectly connected through wired or wireless communication methods. The crowdsourcing device and the server can be directly or indirectly connected through wired or wireless communication methods. The terminal device, crowdsourcing device, and server can be connected to form a blockchain network, which is not limited in this application.

[0125] For easy understanding, please refer to Fig. 1(b). Fig. 1(b) is an interaction schematic diagram of the positioning control system in the embodiment of the present application. As shown in the figure, the terminal device can send a satellite navigation ephemeris request to the CORS server through the unified RTCM standard protocol of the GPS navigation device, such as the data transmission standard of the National Marine Electronics Association (NMEA), etc., so that the CORS server captures satellite signals according to the satellite navigation ephemeris request and demodulates ephemeris data from the satellite signals, such as the full-system ephemeris data within a region or globally. Then, the terminal device can quickly receive the full-system ephemeris data sent by the CORS server based on the RTCM and NTRIP protocols.

[0126] For ease of understanding, the positioning control system in the embodiments of the present application further includes an architecture of a CORS server. The terminal device (such as a mobile phone or an in-vehicle computer, etc.) can broadcast the probability position of the terminal device to the positioning service platform through differential services, so as to implement the position reporting of the terminal device, enabling the positioning service platform to send a satellite navigation ephemeris request carrying the probability position of the terminal device to the CORS server according to the obtained probability position of the terminal device, and receive the original observation data sent by the CORS server, such as the full-system ephemeris data within a region or globally. Then, the positioning service platform can broadcast the full-system ephemeris data to the terminal device through differential services.

[0127] For ease of understanding, please refer to FIG. 1(c). FIG. 1(c) is another interaction schematic diagram of the positioning control system in the embodiments of the present application. As shown in the figure, the terminal device can send a height information acquisition request carrying the terminal approximate position to the regional height database server through the TCP / IP protocol, so that the regional height database server can collect the height information corresponding to the terminal approximate position according to the height information acquisition request. Then, the terminal device can receive the height information broadcast by the regional height database server through the TCP / IP protocol.

[0128] For ease of understanding, please refer to FIG. 1(d). FIG. 1(d) is another interaction schematic diagram of the positioning control system in the embodiments of the present application. As shown in the figure, the terminal device can send a time synchronization request to the time synchronization system server through the TCP / IP protocol, so that the time synchronization system server can capture a time signal according to the time synchronization request to obtain the standard time (such as GPS time). Then, the terminal device can receive the standard time sent by the time synchronization system server through the TCP / IP protocol.

[0129] Combined with the above introduction, the method for determining the terminal position in the present application will be introduced below. Please refer to Figure 2 , an embodiment of the method for determining the terminal position in the embodiments of the present application includes:

[0130] In step S101, obtain the height information corresponding to the terminal approximate position and the Doppler observation value of each satellite;

[0131] In this embodiment, since the target object can perform network connection operations, navigation operations, positioning operations, etc. through the terminal device, the terminal device can receive or sense the operations that the target object wants to perform, and can generate corresponding instructions or requests for the operations that the target object wants to perform, and report the terminal approximate position of the terminal device to the corresponding server to obtain the height information sent by the service and the Doppler observation value of each satellite.

[0132] Among them, the approximate position of the terminal is used to describe the estimated position or approximate position of the terminal device. The approximate position of the terminal can specifically be manifested as the current approximate coordinates detected by the terminal device through a positioning system such as an Assisted Global Positioning System (AGPS), or it can be other manifestations, which are not specifically limited here. Among them, the approximate coordinates can be expressed as non-full-value general coordinates based on incomplete general coordinate values in the Gaussian coordinate system, where the last two digits of the coordinate values are represented in whole kilometers. The general coordinate values can be obtained by converting natural coordinates. The elevation information refers to the distance from a certain point along the plumb line direction to the absolute base surface, and can specifically be manifested as orthometric height, normal height, dynamic height, and geodetic height. The Doppler observation value refers to the geometric distance change rate observation value between the terminal device and the satellite, that is, the pseudorange rate observation value. The Doppler effect (also known as Doppler frequency shift) refers to the frequency difference between transmission and reception caused by the Doppler effect, that is, when the terminal device and the signal source move relative to each other, the change in the frequency received by the terminal device relative to the frequency transmitted by the signal source. That is, when the signal source and the receiver approach, the received frequency increases, and when they move away, it decreases. The Doppler frequency shift can be used to determine the geometric distance change rate between the terminal device and the satellite.

[0133] Specifically, as Figure 15 shown, the target object can perform a positioning operation through the terminal device, so that the terminal device can send a satellite navigation ephemeris request to the CORS server through the RTCM standard protocol (such as NMEA). Then, the terminal device can quickly receive the full-system ephemeris data sent by the CORS server based on the RTCM and NTRIP protocols. Similarly, the terminal device can send an elevation information acquisition request carrying the approximate position of the terminal to the regional elevation database server through the TCP / IP protocol, and then the terminal device can receive the elevation information broadcast by the regional elevation database server through the TCP / IP protocol.

[0134] In step S102, calculate the parameter matrix and the first residual of the elevation information with respect to the terminal position to be solved through the elevation constraint equation;

[0135] In this embodiment, as Figure 17As shown, after obtaining the elevation information corresponding to the approximate position of the terminal and the Doppler observations of each satellite, the obtained elevation information corresponding to the approximate position of the terminal and the Doppler observations of each satellite can be used as the input of the non-linear state parameter estimator integrated in the terminal device. Then, the parameter matrix of the elevation information with respect to the terminal position to be solved and the first residual can be calculated through the elevation constraint equation in the non-linear state parameter estimator. The parameter matrix and the first residual obtained through the elevation constraint equation can assist in the GNSS positioning solution in the weak satellite signal scenario when the number of satellites is small or the regional digital elevation model (DEM) is known.

[0136] Among them, the residual refers to the difference between the measured value and the estimated value predicted by the regression equation, usually denoted by δ, which is used to reflect the accuracy of the regression equation. The residual δ follows the normal distribution N(0, σ2). (δ - the mean of the residuals) / the standard deviation of the residuals is called the standardized residual; δ* follows the standard normal distribution N(0, 1).

[0137] Specifically, as Figure 16 shown, calculating the parameter matrix of the elevation information with respect to the terminal position to be solved and the first residual through the elevation constraint equation can specifically be to calculate the elevation information based on the elevation constraint equation to obtain an elevation prediction matrix, and then take the derivative of the terminal position to be solved based on the elevation prediction matrix to obtain the parameter matrix. Then, the difference between the elevation information and the estimated value of the elevation prediction matrix can be calculated as the first residual.

[0138] In step S103, calculate the first Jacobian matrix and the second residual of the Doppler observation value with respect to the terminal position to be solved and the receiver clock drift through the Doppler observation equation;

[0139] In this embodiment, as Figure 17 shown, after obtaining the elevation information corresponding to the approximate position of the terminal and the Doppler observations of each satellite, the obtained elevation information corresponding to the approximate position of the terminal and the Doppler observations of each satellite can be used as the input of the non-linear state parameter estimator integrated in the terminal device. Then, the parameter matrix of the elevation information with respect to the terminal position to be solved and the first residual can be calculated through the elevation constraint equation in the non-linear state parameter estimator. The parameter matrix and the first residual obtained through the elevation constraint equation can assist in the GNSS positioning solution in the weak satellite signal scenario when the number of satellites is small or the regional digital elevation model (DEM) is known.

[0140] Specifically, as Figure 16As shown, the first Jacobian matrix and the second residual of the Doppler observation value with respect to the terminal position to be solved and the receiver clock drift are calculated through the Doppler observation equation. Specifically, it can be based on the Doppler observation equation to calculate the Doppler observation value to obtain the Doppler observation matrix, and based on the pseudorange observation matrix, the derivative of the terminal position to be solved and the receiver clock drift is taken to obtain the first Jacobian matrix. Then, the difference between the pseudorange observation value and the estimated value of the pseudorange observation matrix can be calculated as the second residual.

[0141] In step S104, the correction amount of the estimated parameters is calculated based on the parameter matrix, the first residual, the first Jacobian matrix, and the second residual, where the estimated parameters include the terminal position to be solved and the receiver clock drift;

[0142] In this embodiment, after obtaining the parameter matrix, the first residual, the first Jacobian matrix, and the second residual, the correction amount of the estimated parameters can be calculated based on the parameter matrix, the first residual, the first Jacobian matrix, and the second residual.

[0143] Among them, the correction amount, that is, the correction number, is used for adjustment. It is the modification of the measured value to make it closer to the true value. The corrected value is the most reliable value. The estimated parameters include the terminal position to be solved and the receiver clock drift, and also include the receiver clock error and the deviation value between the standard time and the current time of the terminal.

[0144] Specifically, as Figure 16 shown, the nonlinear state parameter can be set first as Then the initial value of the nonlinear state parameter is set as x0. Similarly, the estimated parameter of the k-th iteration can be set as x k , and the partial derivative of x k is calculated based on the elevation constraint equation, the Doppler observation equation, and the pseudorange observation equation, that is Furthermore, after constructing the estimated parameters, the correction amount of the estimated parameters can be calculated based on the parameter matrix, the first residual, the first Jacobian matrix, and the second residual.

[0145] In step S105, when the correction amount meets the iteration end condition, the target terminal position is determined according to the terminal position to be solved and the receiver clock drift.

[0146] Specifically, as Figure 16As shown in the figure, after obtaining the correction amount of the estimated parameters, the estimated parameters can be continuously iteratively updated with the correction amount. When the correction amount meets the iteration end condition, such as when the modulus of the correction amount is less than the correction threshold, the estimated parameters corresponding to the current correction amount can be determined as the target estimated parameters. Then, based on the receiver clock drift, receiver clock offset, and the deviation value between the standard time and the current time of the terminal in the target estimated parameters, substitute them into the elevation constraint equation, Doppler observation equation, and pseudorange observation equation to solve the terminal position to be solved, so as to obtain the target terminal position, such as the position information of the longitude, latitude, and altitude of the terminal device.

[0147] In an embodiment of the present application, a method for determining the terminal position is provided. Through the above method, by constructing the elevation constraint equation and Doppler observation equation in a weak satellite signal scenario, and constructing the estimated parameters regarding the terminal position, and based on the obtained elevation information and Doppler observation values, jointly calculate the correction amount of the estimated parameters through the elevation constraint equation and Doppler observation equation, and continuously iteratively optimize the estimated parameters to determine the target terminal position. It can assist the terminal satellite positioning through the joint calculation of the elevation constraint equation and Doppler observation equation and the iterative optimization of the estimated parameters, enhance the availability of satellite positioning in weak satellite signal scenarios such as insufficient ephemeris data or a small number of effective satellites, and realize the positioning solution of the terminal position, thereby improving the accuracy of positioning the terminal position.

[0148] Optionally, based on the above Figure 2 corresponding embodiment, in another optional embodiment of the method for determining the terminal position provided by the embodiment of the present application, as Figure 3 shown, the estimated parameters further include the receiver clock offset and the deviation value between the standard time and the current time of the terminal; step S104 calculates the correction amount of the estimated parameters based on the parameter matrix, the first residual, the first Jacobian matrix, and the second residual, including: step S301; step S105 includes: step S302;

[0149] In step S301, calculate the correction amount of the estimated parameters based on the parameter matrix, the first residual, the first Jacobian matrix, the second residual, the second Jacobian matrix, and the third residual;

[0150] In step S302, when the correction amount meets the iteration end condition, determine the target terminal position according to the terminal position to be solved, the receiver clock drift, the receiver clock offset, and the deviation value between the standard time and the current time of the terminal.

[0151] Specifically, as Figure 16 shown, the nonlinear state parameter can be set to Then set the initial value of the nonlinear state parameter to x0. Similarly, the estimated parameter of the k-th iteration can be set to x k, calculate the partial derivative of x based on the elevation constraint equation, Doppler observation equation, and pseudorange observation equation, i.e., k Further, after constructing the estimation parameters, the correction amount of the estimation parameters can be calculated based on the parameter matrix, the first residual, the first Jacobian matrix, the second residual, the second Jacobian matrix, and the third residual.

[0152] Further, as Figure 16 shown, after obtaining the correction amount of the estimation parameters, the estimation parameters can be continuously iteratively updated with the correction amount. When the correction amount meets the iteration end condition, such as when the modulus of the correction amount is less than the correction threshold, the estimation parameters corresponding to the current correction amount can be determined as the target estimation parameters. Then, based on the receiver clock drift, receiver clock offset, and the deviation value between the standard time and the current time of the terminal in the target estimation parameters, substitute them into the elevation constraint equation, Doppler observation equation, and pseudorange observation equation to solve the position of the terminal to be solved, so as to obtain the target terminal position, such as the position information of the longitude, latitude, and altitude of the terminal device.

[0153] Optionally, based on the corresponding embodiment above, in another optional embodiment of the method for determining the terminal position provided by the embodiments of the present application, as Figure 2 shown, before calculating the correction amount of the estimation parameters based on the parameter matrix, the first residual, the first Jacobian matrix, the second residual, the second Jacobian matrix, and the third residual in step S301, the method further includes: Figure 3

[0154] In step S3011, obtain the pseudorange observation value of each satellite and the standard time;

[0155] In step S3012, calculate the second Jacobian matrix and the third residual of the pseudorange observation value and the standard time with respect to the position of the terminal to be solved, receiver clock offset, deviation value between the standard time and the current time of the terminal, and time system deviation through the pseudorange observation equation.

[0156] In this embodiment, in order to avoid the situation where the terminal device cannot be positioned and solved when the GPS time of week (TOW) cannot be obtained, this embodiment can obtain the pseudorange observation value of each satellite and the standard time, and calculate the second Jacobian matrix and the third residual of the pseudorange observation value and the standard time with respect to the position of the terminal to be solved, receiver clock offset, deviation value between the standard time and the current time of the terminal, and time system deviation through the pseudorange observation equation. Then, based on the parameter matrix, the first residual, the first Jacobian matrix, the second residual, the second Jacobian matrix, and the third residual, the correction amount of the estimation parameters can be better calculated, so as to realize the positioning and solution of the terminal position by combining the external time with the correction amount, thereby improving the accuracy of obtaining the terminal position to a certain extent. ​​

[0157] Specifically, as Figure 15 shown, the terminal device can send a time synchronization request to the time synchronization system server through the TCP / IP protocol, so that the time synchronization system server captures a time signal according to the time synchronization request to obtain the standard time (such as GPS time). Then, the terminal device can receive the standard time sent by the time synchronization system server through the TCP / IP protocol.

[0158] Furthermore, the second Jacobian matrix and the third residual of the pseudorange observation value and the standard time with respect to the terminal position to be solved, the receiver clock error, the deviation value between the standard time and the current time of the terminal, and the time system deviation are calculated through the pseudorange observation equation. Specifically, the pseudorange observation value can be calculated based on the pseudorange observation equation to obtain the pseudorange observation matrix, and based on the pseudorange observation matrix, derivatives are taken with respect to the terminal position to be solved, the receiver clock error, the deviation value between the standard time and the current time of the terminal, and the time system deviation to obtain the second Jacobian matrix. Then, the difference between the pseudorange observation value and the estimated value of the pseudorange observation matrix is calculated as the third residual.

[0159] Optionally, on the basis of the above Figure 3 corresponding embodiment, in another optional embodiment of the method for determining the terminal position provided by the embodiment of the present application, as Figure 4 shown, before step S301 calculates the correction amount of the estimated parameter based on the parameter matrix, the first residual, the first Jacobian matrix, the second residual, the second Jacobian matrix, and the third residual, the method further includes: step S401; step S301 includes: steps S402 to S403;

[0160] In step S401, a weight matrix is calculated based on the elevation angle of each satellite and the signal-to-noise ratio of the pseudorange observation value;

[0161] In step S402, the partial derivative of the estimated parameter is calculated based on the parameter matrix, the first Jacobian matrix, and the second Jacobian matrix;

[0162] In step S403, the correction amount of the estimated parameter is calculated based on the partial derivative, the weight matrix, the first residual, the second residual, and the third residual.

[0163] Specifically, as Figure 16 shown, the weight matrix can be calculated by the following formula (1) based on the elevation angle of each satellite and the signal-to-noise ratio of the pseudorange observation value:

[0164]

[0165] where, where, CN0 i is the signal-to-noise ratio of the pseudorange observation value of satellite i, eli Denotes the elevation angle of satellite i.

[0166] Furthermore, the partial derivatives of the estimated parameters can be calculated as follows in (2) based on the parameter matrix, the first Jacobian matrix, and the second Jacobian matrix, and the correction amount of the estimated parameters can be calculated based on the partial derivatives, the weight matrix, the first residual, the second residual, and the third residual:

[0167]

[0168] where x k+1 = x k + Δx, and z hk , and z ρk are the elevation constraint, the Doppler observation value, and the pseudorange observation value residual, that is, the first residual, the second residual, and the third residual.

[0169] Optionally, based on the corresponding embodiment above Figure 3 In another optional embodiment of the method for determining the terminal position provided by the embodiments of the present application, as Figure 5 shown, before step S3012, constructing the pseudorange observation equation includes the following steps:

[0170] In step S501, based on the terminal position to be solved, the receiver clock error, the deviation value between the standard time and the current time of the terminal, the error correction number, and the speed of light value in vacuum, construct the mathematical model of the pseudorange observation value;

[0171] In step S502, based on the mathematical model of the pseudorange observation value, construct the pseudorange observation equation for N satellites, where N is an integer greater than or equal to 1.

[0172] In this embodiment, before calculating the second Jacobian matrix and the third residual of the pseudorange observation value and the standard time with respect to the terminal position to be solved, the receiver clock error, the deviation value between the standard time and the current time of the terminal, and the time system deviation, based on the terminal position to be solved, the receiver clock error, the deviation value between the standard time and the current time of the terminal, the error correction number, and the speed of light value in vacuum, construct the mathematical model of the pseudorange observation value, and based on the mathematical model of the pseudorange observation value, construct the pseudorange observation equation for N satellites, increasing the effective observation data, thereby improving the accuracy of obtaining the terminal device positioning to a certain extent.

[0173] Among them, the terminal position to be solved, the receiver clock error, the deviation value between the standard time and the current time of the terminal, the error correction number, and the speed of light value in vacuum can be used to represent the parameters of the conventional pseudorange positioning algorithm.

[0174] Specifically, a mathematical model for constructing pseudorange observations can be adopted as shown in Equation (3) based on the position of the terminal to be solved, the receiver clock error, the deviation value between the standard time and the current time of the terminal, the error correction number, and the speed of light in vacuum:

[0175]

[0176] Among them, is the pseudorange observation value of satellite i, r u is the position of the terminal device, i.e., the position of the terminal to be solved, r i is the position of satellite i, dt r is the terminal clock deviation, dt i is the clock error of satellite i, c is the speed of light in vacuum, ζ is the error correction number (including ionospheric, tropospheric, and earth rotation corrections, which can be calculated by empirical models), v i is the speed of satellite i, is the satellite clock error rate, which can be calculated from the navigation ephemeris, represents the unit observation vector from the terminal device to satellite i, and ISB(i) represents the system time deviation between the satellite navigation system where satellite i is located and GPS: when i is GPS, ISB(i) = 0; when i is the Beidou satellite navigation system, ISB(i) = ISB(BDS); when i is GLONASS, ISB(i) = ISB(GLO); when i is GALILEO, ISB(i) = ISB(GAL). In this solution, we calibrate ISB(BDS), ISB(GLO), and ISB(GAL) through the GNSS pseudorange observations collected in advance, that is, ISB(i) can be considered known. δt represents the deviation value between the accurate time obtained from the timing system and the current time of the terminal;

[0177] Assuming there are N satellites, the following Equation (4), i.e., the pseudorange observation equation, can be formed:

[0178]

[0179] Optionally, based on the above Figure 3 corresponding embodiment, in another optional embodiment of the method for determining the terminal position provided by the embodiments of the present application, as Figure 6 shown, calculating the second Jacobian matrix and the third residual of the pseudorange observation value and the standard time with respect to the position of the terminal to be solved, the receiver clock error, the deviation value between the standard time and the current time of the terminal, and the time system deviation through the pseudorange observation equation, including:

[0180] In step S601, calculating the pseudorange observation value based on the pseudorange observation equation to obtain a pseudorange observation matrix;

[0181] In step S602, based on the pseudorange observation matrix, derivatives are taken with respect to the terminal position to be solved, the receiver clock error, the deviation value between the standard time and the current moment of the terminal, and the time system deviation, to obtain a second Jacobian matrix;

[0182] In step S603, based on the pseudorange observations and the estimated value of the pseudorange observation matrix, a third residual is determined.

[0183] Specifically, after obtaining the pseudorange observation equation (4) and the pseudorange observations, the pseudorange observations can be calculated based on the pseudorange observation equation to obtain the pseudorange observation matrix, and the following equation (5) is used to take derivatives with respect to the terminal position to be solved, the receiver clock error, the deviation value between the standard time and the current moment of the terminal, and the time system deviation based on the pseudorange observation matrix, to obtain a second Jacobian matrix:

[0184]

[0185] Furthermore, based on equations (4) and (5) above, the difference between the pseudorange observations and the estimated value of the pseudorange observation matrix can be calculated to obtain a third residual.

[0186] Optionally, based on the above Figure 5 corresponding embodiment, in another optional embodiment of the method for determining the terminal position provided by the embodiments of the present application, as Figure 7 shown, before step S302 determines the target terminal position according to the terminal position to be solved, the receiver clock drift, the receiver clock error, and the deviation value between the standard time and the current moment of the terminal when the correction amount meets the iteration end condition, the method further includes: steps S701 to S702; step S302 includes: step S703.

[0187] In step S701, the mathematical model of the pseudorange observations is optimized based on the external time deviation to obtain a mathematically optimized model of the pseudorange observations;

[0188] In step S702, a terminal time deviation correction equation for N satellites is constructed based on the mathematically optimized model of the pseudorange observations;

[0189] In step S703, the second Jacobian matrix and the third residual of the pseudorange observations and the standard time with respect to the terminal position to be solved, the receiver clock error, the deviation value between the standard time and the current moment of the terminal, and the time system deviation are calculated through the terminal time deviation correction equation.

[0190] Specifically, as Figure 19 shown, based on equation (4) above, on the basis of the mathematical model of the pseudorange observations, the external time deviation δ△t is added to obtain, as Figure 19 shown, the mathematically optimized model of the pseudorange observations Furthermore, a terminal time deviation correction equation for N satellites is constructed based on the mathematical optimization model of pseudorange observations.

[0191] Further, the second Jacobian matrix and the third residual of the pseudorange observation value and the standard time with respect to the to-be-solved terminal position, receiver clock error, deviation value between the standard time and the current terminal time, and time system deviation can be calculated through the terminal time deviation correction equation. Specifically, the external time can be calculated from the pseudorange observation value and the standard time, and substituted into the terminal time deviation correction equation, the Jacobian matrix of the deviation and the parameter Jacobian matrix, and then the to-be-solved terminal position, receiver clock error, deviation value between the standard time and the current terminal time, and time system deviation are differentiated to obtain the second Jacobian matrix. Then, the difference between the pseudorange observation value and the estimated value obtained based on the terminal time deviation correction equation is calculated to obtain the third residual.

[0192] Optionally, based on the above Figure 2 corresponding embodiment, in another optional embodiment of the method for determining the terminal position provided by the embodiments of the present application, as Figure 8 shown, before step S102, constructing the elevation constraint equation includes the following steps:

[0193] In step S801, based on the elevation prior information, the constraint condition between the terminal geodetic coordinates and the to-be-solved terminal position, the prior error of the terminal geodetic coordinates, and the prior error of the to-be-solved terminal position are constructed;

[0194] In step S802, based on the constraint condition and the prior error of the terminal geodetic coordinates, the prior error of the to-be-solved terminal position is expanded by Taylor series;

[0195] In step S803, the Taylor series expansion is sorted out to obtain the elevation constraint equation.

[0196] In this embodiment, before calculating the parameter matrix and the first residual of the elevation information with respect to the to-be-solved terminal position through the elevation constraint equation, the constraint condition between the terminal geodetic coordinates and the to-be-solved terminal position, the prior error of the terminal geodetic coordinates, and the prior error of the to-be-solved terminal position can be constructed according to the preset elevation prior information, and the prior error of the to-be-solved terminal position is expanded by Taylor series based on the constraint condition and the prior error of the terminal geodetic coordinates. Then, the Taylor series expansion can be sorted out to obtain the elevation constraint equation, so that subsequent effective observation data can be increased through the elevation constraint equation, thereby improving the positioning accuracy of the terminal device to a certain extent.

[0197] Specifically, as Figure 18 shown, assuming the to-be-solved terminal position is (x u , y u, z u ), the prior elevation information is represented as the prior value of the geodetic coordinates being and That is, there is the following equation (3):

[0198]

[0199] where is used to represent the prior error of the ECEF coordinates of the terminal device, i.e., the prior error of the terminal position to be solved, and is used to represent the prior error of the geodetic coordinates of the terminal.

[0200] Furthermore, the constraint condition between the geodetic coordinates of the terminal and the terminal position to be solved is constructed as follows (4):

[0201]

[0202] where are respectively used to represent the radius of the meridian and the radius of the prime vertical, where a e is the semi-major axis of the reference ellipsoid.

[0203] Furthermore, performing Taylor series expansion gives the following equation (5):

[0204]

[0205] Furthermore, organizing the Taylor series expansion gives the following equation (6):

[0206]

[0207] Optionally, based on the above Figure 2 corresponding embodiment, in another optional embodiment of the method for determining the terminal position provided by the embodiments of the present application, as Figure 9 shown, step S102 calculates the parameter matrix and the first residual of the elevation information with respect to the terminal position to be solved through the elevation constraint equation, including:

[0208] In step S901, based on the elevation constraint equation, the elevation information is calculated to obtain an elevation prediction matrix;

[0209] In step S902, based on the elevation prediction matrix, the terminal position to be solved is differentiated to obtain a parameter matrix;

[0210] In step S903, based on the elevation information and the estimated value of the elevation prediction matrix, the first residual is determined.

[0211] Specifically, if the elevation information is represented as orthometric height, where the measured value of the orthometric height is represented as then there is is the measurement error of the geodetic height, i.e., the first residual, h u is the estimated value of the geodetic height, then there are the following equations (7) and (8):

[0212]

[0213] wherein, is the variance value of the measurement error of the geodetic height, i.e., the first residual

[0214] Furthermore, based on the elevation prediction matrix, elevation constraint equations (6), (7) and (8) are used to calculate the elevation information to obtain the elevation prediction matrix. Then, based on the obtained elevation prediction matrix, the derivative of the terminal position to be solved is taken to obtain the parameter matrix. Furthermore, by calculating the difference between the elevation information and the estimated value of the elevation prediction matrix, the first residual is obtained

[0215] Optionally, on the basis of the above Figure 2 corresponding embodiment, in another optional embodiment of the method for determining the terminal position provided by the embodiment of the present application, as Figure 10 shown, before step S103, constructing the Doppler observation equation includes the following steps:

[0216] In step S1001, based on the terminal position to be solved, the receiver clock drift, the wavelength of the satellite broadcast signal, and the speed of light in vacuum, a mathematical model of the Doppler observation value is constructed

[0217] In step S1002, based on the mathematical model of the Doppler observation value, Doppler observation equations for N satellites are constructed

[0218] In this embodiment, before calculating the first Jacobian matrix and the second residual of the Doppler observation value with respect to the terminal position to be solved and the receiver clock drift through the Doppler observation equation, based on non-linear state parameters such as the terminal position to be solved and the receiver clock drift, and the wavelength of the satellite broadcast signal and the speed of light in vacuum, a mathematical model of the Doppler observation value for one satellite is constructed. Then, based on the mathematical model of the Doppler observation value, Doppler observation equations for N satellites are constructed, so that subsequent effective observation data can be increased through the Doppler observation equation, thereby improving the positioning accuracy of the terminal device to a certain extent

[0219] Specifically, assuming that the terminal device receives the Doppler observation values of N satellites, and at the same time, considering that the speed of the terminal device is slow during the initial positioning, there is the following equation (9):

[0220]

[0221] where λ is the wavelength of the satellite broadcast signal is the Doppler observation value, v i , i = 1, 2, ……, n is the satellite running speed, is the clock drift of the terminal receiver, is the satellite clock drift.

[0222] Optionally, based on the above Figure 2 corresponding embodiment, in another optional embodiment of the method for determining the terminal position provided by the embodiment of the present application, as Figure 11 shown, step S103 calculates the first Jacobian matrix and the second residual of the Doppler observation value with respect to the terminal position to be solved and the receiver clock drift through the Doppler observation equation, including:

[0223] In step S1101, based on the Doppler observation equation, the Doppler observation value is calculated to obtain the Doppler observation matrix;

[0224] In step S1102, based on the Doppler observation matrix, the derivative of the terminal position to be solved and the receiver clock drift is obtained to obtain the first Jacobian matrix;

[0225] In step S1103, based on the Doppler observation value and the estimated value of the Doppler observation matrix, the second residual is determined.

[0226] Specifically, calculate the Jacobian matrix of the Doppler observation value with respect to the terminal position r u and the receiver clock drift , that is, the first Jacobian matrix, as shown in the following formula (10):

[0227]

[0228] Based on the above formula (9) Doppler observation equation, the Doppler observation value is calculated to obtain the Doppler observation matrix, and based on the Doppler observation matrix and combined with the above formula (10), the derivative of the terminal position to be solved and the receiver clock drift is obtained to obtain the first Jacobian matrix. Then, the difference between the Doppler observation value and the estimated value of the Doppler observation matrix can be calculated to obtain the second residual.

[0229] Optionally, based on the above Figure 3 corresponding embodiment, in another optional embodiment of the method for determining the terminal position provided by the embodiment of the present application, as Figure 12 shown, when the iteration end condition is that the modulus of the correction amount is less than the correction threshold; in step S105, when the correction amount meets the iteration end condition, the target terminal position is determined according to the terminal position to be solved, the receiver clock drift, the receiver clock error, and the deviation value between the standard time and the current time of the terminal, including:

[0230] In step S1201, when the modulus of the correction amount is less than the correction threshold, the target estimated parameter is determined;

[0231] In step S1202, the terminal position to be solved is calculated based on the receiver clock drift, receiver clock offset in the target estimation parameters, and the deviation value between the standard time and the current time of the terminal, and the target terminal position is obtained.

[0232] Specifically, based on the following formula (11), by calculating the modulus of the correction amount, when the modulus of the correction amount is less than the correction threshold, the current estimation parameters can be used as the target estimation parameters:

[0233] ‖Δx‖<10 -4 (11);

[0234] Furthermore, the terminal position to be solved is calculated based on the receiver clock drift, receiver clock offset in the target estimation parameters, and the deviation value between the standard time and the current time of the terminal. Specifically, the terminal position to be solved can be calculated based on the above formulas (6) to (10), and the target terminal position can be obtained.

[0235] Optionally, based on the above Figure 3 corresponding embodiment, in another optional embodiment of the terminal position determination method provided by the embodiments of the present application, as Figure 13 shown, step S101 of obtaining the elevation information corresponding to the terminal approximate position and the Doppler observation values of each satellite includes: steps S1301 to step S1035; step S3011 includes: step S1306;

[0236] In step S1301, an elevation information acquisition request carrying the elevation information of the terminal approximate position is sent to the regional elevation database server, so that the regional elevation database server collects the elevation information corresponding to the terminal approximate position according to the elevation information acquisition request;

[0237] In step S1302, the elevation information broadcast by the regional elevation database server is received;

[0238] In step S1303, a satellite navigation ephemeris request is sent to the continuous operation reference station CORS server, so that the CORS server queries the ephemeris data according to the satellite navigation ephemeris request;

[0239] In step S1304, the full-system ephemeris data sent by the CORS server is received;

[0240] In step S1305, the Doppler observation values are extracted from the full-system ephemeris data;

[0241] In step S1306, the pseudorange observation values corresponding to the terminal approximate position are extracted from the full-system ephemeris data, and the standard time is obtained.

[0242] In this embodiment, when it is necessary to locate the terminal device, an elevation information acquisition request carrying the approximate location of the terminal can be sent to the regional elevation database server, so that the regional elevation database server can collect the elevation information corresponding to the approximate location of the terminal according to the elevation information acquisition request, enabling the terminal device to receive the elevation information broadcast by the regional elevation database server. At the same time, a satellite navigation ephemeris request can also be sent to the continuous operating reference station CORS server, so that the CORS server can query the ephemeris data according to the satellite navigation ephemeris request, enabling the terminal device to receive the full-system ephemeris data sent by the CORS server and extract the pseudorange observation value and Doppler observation value corresponding to the approximate location of the terminal from the full-system ephemeris data.

[0243] Among them, the full-system ephemeris data includes but is not limited to the position, velocity, satellite clock, and orbital data of each satellite, etc., and no specific restrictions are made here. The regional elevation database server is used to collect and store elevation information and elevation data. Among them, the elevation data can be applied to multiple scenarios such as terrain analysis, slope and aspect analysis, or contour analysis. The elevation data is the elevation mathematical model, which can specifically be represented as a Digital Elevation Model (DEM), or can also be represented as other models, such as a Digital Surface Model (DSM) or a Digital Terrain Model (DTM), etc., and no specific restrictions are made here. However, the Digital Surface Model (DSM) is usually applied to scenarios such as landscape modeling, urban modeling, or visualization applications, and the Digital Terrain Model (DTM) is usually used in scenarios such as flood or drainage modeling, land use research, geological applications, and other applications.

[0244] Specifically, as Figure 15 shown, the terminal device can send an elevation information acquisition request carrying the approximate location of the terminal to the regional elevation database server through the TCP / IP protocol. After receiving the elevation information acquisition request, the regional elevation database server can collect the elevation information corresponding to the approximate location of the terminal based on the elevation information acquisition request, and then send it to the terminal device through the TCP / IP protocol, enabling the terminal device to receive the elevation information broadcast by the regional elevation database server through the TCP / IP protocol, thereby improving the efficiency of obtaining terminal positioning to a certain extent.

[0245] It can be understood that if there is historical elevation information corresponding to the terminal device in the regional elevation database, the currently obtained elevation information can be used to update the historical elevation information. Conversely, if there is no historical elevation information corresponding to the terminal device in the regional elevation database, the currently obtained elevation information can be stored corresponding to the terminal device identifier for easy query or use.

[0246] Furthermore, as Figure 15As shown, the terminal device can also send a satellite navigation ephemeris request to the CORS server through the unified RTCM standard protocol of the GPS navigation device, such as the National Marine Electronics Association (NMEA) and other data transmission standard industrial associations, so that the CORS server captures satellite signals according to the satellite navigation ephemeris request and demodulates the navigation ephemeris data from the satellite signals, such as the full-system ephemeris data within a region or globally. Furthermore, the CORS server can send it to the server through the RTCM and NTRIP protocols, so that the terminal device can quickly receive the full-system ephemeris data sent by the CORS server based on the RTCM and NTRIP protocols, which can improve the efficiency of obtaining the terminal position to a certain extent. Then, the pseudorange observation value and the Doppler observation value corresponding to the approximate position of the terminal can be extracted from the full-system ephemeris data, so that the position of the terminal device can be more accurately calculated based on the pseudorange observation value and the Doppler observation value through the pseudorange observation equation and the Doppler observation equation in the follow-up.

[0247] Optionally, on the basis of the corresponding embodiment above Figure 13 In another optional embodiment of the method for determining the terminal position provided by the embodiment of the present application, as Figure 14 shown, step S1306 of obtaining the standard time includes:

[0248] In step S1401, send a time synchronization request to the time synchronization system server so that the time synchronization system server queries the standard time according to the time synchronization request;

[0249] In step S1402, receive the standard time sent by the time synchronization system server.

[0250] In this embodiment, in order to avoid the situation where the terminal device cannot be positioned and solved when the GPS Time of Week (TOW) is unknown, in this embodiment, a time synchronization request is sent to the time synchronization system server so that the time synchronization system server queries the standard time according to the time synchronization request, so that the terminal device can receive the standard time sent by the time synchronization system server, so that the position of the terminal device can be positioned and solved based on the standard time obtained by the time synchronization system through the pseudorange observation equation and the terminal time deviation correction equation in the follow-up, thereby improving the accuracy of positioning the terminal device to a certain extent.

[0251] Among them, the timing system mainly consists of a time reference, a transmission link, and a timing module. Among them, the time reference can specifically be represented by the four major satellite navigation systems, namely the Global Positioning System (GPS), the Beidou Satellite Navigation System (BDS), the GLONASS Satellite Navigation System (GLONASS), and the Galileo Positioning System (GALILEO). The transmission link refers to the means of sending time signals to terminal devices, which can specifically be represented by shortwave, longwave, satellite, optical fiber, or the Internet, etc., and can also be represented in other forms, without specific limitations here. The timing module is used to extract the timing information after modulation or coding, eliminate the errors and jitters brought by the transmission path, and provide an accurate and stable time information, that is, the standard time, for the terminal device.

[0252] Specifically, as Figure 15 shown, the terminal device can send a timing request to the timing system server through the TCP / IP protocol, so that the timing system server captures the time signal according to the timing request to obtain the standard time (such as GPS time). Then, the terminal device can receive the standard time sent by the timing system server through the TCP / IP protocol.

[0253] The following will describe in detail the device for determining the terminal position in this application. Please refer to Figure 20 , Figure 20 which is a schematic diagram of an embodiment of the device for determining the terminal position in an embodiment of this application. The device 20 for determining the terminal position includes:

[0254] An acquisition unit 201, configured to acquire the elevation information corresponding to the approximate position of the terminal and the Doppler observations of each satellite;

[0255] A processing unit 202, configured to calculate the parameter matrix of the elevation information with respect to the terminal position to be solved and the first residual through the elevation constraint equation;

[0256] The processing unit 202 is further configured to calculate the first Jacobian matrix and the second residual of the Doppler observations with respect to the terminal position to be solved and the receiver clock drift through the Doppler observation equation;

[0257] The processing unit 202 is further configured to calculate the correction amount of the estimated parameters based on the parameter matrix, the first residual, the first Jacobian matrix, and the second residual, where the estimated parameters include the terminal position to be solved and the receiver clock drift;

[0258] A determination unit 203, configured to determine the target terminal position according to the terminal position to be solved and the receiver clock drift when the correction amount meets the iteration end condition.

[0259] Optionally, based on the corresponding embodiment above Figure 20 in another embodiment of the device for determining the terminal position provided in the embodiment of this application,

[0260] The processing unit 202 can specifically be used for: calculating a correction amount of the estimated parameter based on a parameter matrix, a first residual, a first Jacobian matrix, a second residual, a second Jacobian matrix, and a third residual;

[0261] The determination unit 203 can specifically be used for: when the correction amount meets the iteration end condition, determining the target terminal position according to the to-be-solved terminal position, the receiver clock drift, the receiver clock error, and the deviation value between the standard time and the current moment of the terminal.

[0262] Optionally, based on the above Figure 20 corresponding embodiment, in another embodiment of the terminal position determination device provided by the embodiments of the present application,

[0263] The acquisition unit 201 is further used for acquiring the pseudorange observation value of each satellite and the standard time;

[0264] The processing unit 202 is further used for calculating a second Jacobian matrix and a third residual of the pseudorange observation value and the standard time with respect to the to-be-solved terminal position, the receiver clock error, the deviation value between the standard time and the current moment of the terminal, and the time system deviation through a pseudorange observation equation.

[0265] Optionally, based on the above Figure 20 corresponding embodiment, in another embodiment of the terminal position determination device provided by the embodiments of the present application,

[0266] The processing unit 202 is further used for calculating a weight matrix based on the elevation angle of each satellite and the signal-to-noise ratio of the pseudorange observation value;

[0267] The processing unit 202 can specifically be used for: calculating a partial derivative of the estimated parameter based on a parameter matrix, a first Jacobian matrix, and a second Jacobian matrix;

[0268] Calculating a correction amount of the estimated parameter based on the partial derivative, the weight matrix, the first residual, the second residual, and the third residual.

[0269] Optionally, based on the above Figure 20 corresponding embodiment, in another embodiment of the terminal position determination device provided by the embodiments of the present application, the processing unit 202 can specifically be used for:

[0270] Constructing a mathematical model of the pseudorange observation value based on the to-be-solved terminal position, the receiver clock error, the deviation value between the standard time and the current moment of the terminal, the error correction number, and the speed of light value in vacuum;

[0271] Constructing a pseudorange observation equation for N satellites based on the mathematical model of the pseudorange observation value, where N is an integer greater than or equal to 1.

[0272] Optionally, based on the aboveFigure 20 Based on the corresponding embodiment, in another embodiment of the terminal position determination device provided in the embodiments of the present application, the processing unit 202 may specifically be used for:

[0273] Calculating the pseudorange observation values based on the pseudorange observation equation to obtain a pseudorange observation matrix;

[0274] Deriving the second Jacobian matrix for the terminal position to be solved, the receiver clock error, the deviation value between the standard time and the current terminal time, and the time system deviation based on the pseudorange observation matrix;

[0275] Determining a third residual based on the pseudorange observation values and the estimated values of the pseudorange observation matrix.

[0276] Optionally, based on the above Figure 20 Based on the corresponding embodiment, in another embodiment of the terminal position determination device provided in the embodiments of the present application, the processing unit 202 may specifically be used for:

[0277] Optimizing the mathematical model of the pseudorange observation values based on the external time deviation to obtain a mathematically optimized model of the pseudorange observation values;

[0278] Constructing a terminal time deviation correction equation for N satellites based on the mathematically optimized model of the pseudorange observation values;

[0279] The processing unit 202 may specifically be used for: calculating the second Jacobian matrix and the third residual of the pseudorange observation values and the standard time with respect to the terminal position to be solved, the receiver clock error, the deviation value between the standard time and the current terminal time, and the time system deviation through the terminal time deviation correction equation.

[0280] Optionally, based on the above Figure 20 Based on the corresponding embodiment, in another embodiment of the terminal position determination device provided in the embodiments of the present application, the processing unit 202 may specifically be used for:

[0281] Constructing constraint conditions between the terminal geodetic coordinates and the terminal position to be solved, the prior error of the terminal geodetic coordinates, and the prior error of the terminal position to be solved based on the elevation prior information;

[0282] Performing a Taylor series expansion on the prior error of the terminal position to be solved based on the constraint conditions and the prior error of the terminal geodetic coordinates;

[0283] Rearranging the Taylor series expansion to obtain an elevation constraint equation.

[0284] Optionally, based on the above Figure 20Based on the corresponding embodiment, in another embodiment of the terminal position determination device provided in the embodiments of the present application, the processing unit 202 may specifically be configured to:

[0285] Calculate the elevation information based on the elevation constraint equation to obtain an elevation prediction matrix;

[0286] Derive the parameter matrix by taking the derivative of the terminal position to be solved based on the elevation prediction matrix;

[0287] Determine the first residual based on the elevation information and the estimated value of the elevation prediction matrix.

[0288] Optionally, based on the above Figure 20 Based on the corresponding embodiment, in another embodiment of the terminal position determination device provided in the embodiments of the present application, the processing unit 202 may specifically be configured to:

[0289] Construct a mathematical model of the Doppler observation value based on the terminal position to be solved, the receiver clock drift, the wavelength of the satellite broadcast signal, and the speed of light value in vacuum;

[0290] Construct Doppler observation equations for N satellites based on the mathematical model of the Doppler measurement value.

[0291] Optionally, based on the above Figure 20 Based on the corresponding embodiment, in another embodiment of the terminal position determination device provided in the embodiments of the present application, the processing unit 202 may specifically be configured to:

[0292] Calculate the Doppler observation value based on the Doppler observation equation to obtain a Doppler observation matrix;

[0293] Derive the first Jacobian matrix by taking the derivative of the terminal position to be solved and the receiver clock drift based on the Doppler observation matrix;

[0294] Determine the second residual based on the Doppler observation value and the estimated value of the Doppler observation matrix.

[0295] Optionally, based on the above Figure 20 Based on the corresponding embodiment, in another embodiment of the terminal position determination device provided in the embodiments of the present application, the processing unit 202 may specifically be configured to:

[0296] When the modulus of the correction amount is less than the correction threshold, determine the target estimation parameter;

[0297] Solve the terminal position to be solved based on the receiver clock drift, receiver clock offset, and the deviation value between the standard time and the current time of the terminal in the target estimation parameter to obtain the target terminal position.

[0298] Optionally, based on the above Figure 20Based on the corresponding embodiment, in another embodiment of the terminal location determination device provided in the embodiments of the present application, the obtaining unit 201 may specifically be used for:

[0299] Send an elevation information acquisition request carrying the approximate location of the terminal to the regional elevation database server, so that the regional elevation database server collects elevation information corresponding to the approximate location of the terminal according to the elevation information acquisition request;

[0300] Receive the elevation information broadcast by the regional elevation database server;

[0301] Send a satellite navigation ephemeris request to the continuously operating reference station CORS server, so that the CORS server queries ephemeris data according to the satellite navigation ephemeris request;

[0302] Receive the full-system ephemeris data sent by the CORS server;

[0303] Extract Doppler observations from the full-system ephemeris data;

[0304] The obtaining unit may specifically be used for: extracting pseudorange observations corresponding to the approximate location of the terminal from the full-system ephemeris data, and obtaining the standard time.

[0305] Optionally, based on the above Figure 20 Based on the corresponding embodiment, in another embodiment of the terminal location determination device provided in the embodiments of the present application, the obtaining unit 201 may specifically be used for:

[0306] Send a timing request to the timing system server, so that the timing system server queries the standard time according to the timing request;

[0307] Receive the standard time sent by the timing system server.

[0308] On the other hand, the present application provides another schematic diagram of a computer device, as Figure 21 shown, Figure 21FIG. 0 is a schematic structural diagram of a computer device provided by an embodiment of the present application. The computer device 300 may vary greatly due to different configurations or performances, and may include one or more central processing units (CPUs) 310 (for example, one or more processors) and a memory 320, and one or more storage media 330 (for example, one or more mass storage devices) for storing application programs 331 or data 332. Among them, the memory 320 and the storage media 330 may be transient storage or persistent storage. The program stored in the storage media 330 may include one or more modules (not shown in the figure), and each module may include a series of instruction operations on the computer device 300. Further, the central processor 310 may be configured to communicate with the storage media 330 and execute a series of instruction operations in the storage media 330 on the computer device 300.

[0309] The computer device 300 may further include one or more power supplies 340, one or more wired or wireless network interfaces 350, one or more input / output interfaces 360, and / or one or more operating systems 333, such as Windows Server TM , Mac OS X TM , Unix TM , Linux TM , FreeBSD TM and so on.

[0310] The above computer device 300 is further configured to execute the steps in the corresponding embodiments as Figures 2 to 14 shown.

[0311] On the other hand, the present application provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps in the method described in the embodiments as Figures 2 to 14 shown are implemented.

[0312] On the other hand, the present application provides a computer program product including a computer program. When the computer program is executed by a processor, the steps in the method described in the embodiments as Figures 2 to 14 shown are implemented.

[0313] Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working processes of the above-described systems, devices, and units can refer to the corresponding processes in the foregoing method embodiments, and will not be described herein again.

[0314] In several embodiments provided by the present application, it should be understood that the disclosed systems, devices, and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed couplings or direct couplings or communication connections to each other can be through some interfaces, and the indirect couplings or communication connections of devices or units can be in electrical, mechanical, or other forms.

[0315] The units described as separate components may or may not be physically separated. The components displayed as units may or may not be physical units, that is, they can be located in one place or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0316] In addition, in each embodiment of the present application, the functional units can be integrated in a processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit. The above-mentioned integrated units can be implemented in the form of hardware or in the form of software functional units.

[0317] If the above-mentioned integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art, or all or part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in each embodiment of the present application. The aforementioned storage medium includes: USB flash drives, mobile hard disks, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical discs and other various media that can store program codes.

Claims

1. A method for determining the position of a terminal, characterized in that, Including: Obtain the elevation information corresponding to the approximate position of the terminal and the Doppler observations of each satellite; Calculate the parameter matrix of the elevation information with respect to the terminal position to be solved and the first residual through the elevation constraint equation; Calculate the first Jacobian matrix of the Doppler observations with respect to the terminal position to be solved and the receiver clock drift and the second residual through the Doppler observation equation; Obtain the pseudorange observations of each satellite and the standard time; Calculate the second Jacobian matrix and the third residual of the pseudorange observations and the standard time with respect to the terminal position to be solved, the receiver clock error, the deviation between the standard time and the current time of the terminal, and the time system deviation through the pseudorange observation equation; Calculate the partial derivatives of the estimated parameters based on the parameter matrix, the first Jacobian matrix, and the second Jacobian matrix; Calculate the correction amount of the estimated parameters based on the partial derivatives, the weight matrix, the first residual, the second residual, and the third residual, where the estimated parameters include the terminal position to be solved, the receiver clock drift, and the receiver clock error, and the deviation between the standard time and the current time of the terminal; When the correction amount meets the iteration end condition, determine the target terminal position according to the terminal position to be solved and the receiver clock drift.

2. The method according to claim 1, wherein The step of when the correction amount meets the iteration end condition, determining the target terminal position according to the terminal position to be solved and the receiver clock drift includes: When the correction amount meets the iteration end condition, determine the target terminal position according to the terminal position to be solved, the receiver clock drift, the receiver clock error, and the deviation between the standard time and the current time of the terminal.

3. The method according to claim 1, wherein Before calculating the partial derivatives of the estimated parameters based on the parameter matrix, the first Jacobian matrix, and the second Jacobian matrix, the method further includes: Calculate the weight matrix based on the elevation angle of each satellite and the signal-to-noise ratio of the pseudorange observations.

4. The method according to claim 2, wherein Constructing the pseudorange observation equation includes the following steps: Based on the terminal position to be solved, the receiver clock error, the deviation between the standard time and the current time of the terminal, the error correction number, and the speed of light value in vacuum, construct the mathematical model of the pseudorange observations; Based on the mathematical model of the pseudorange observations, construct the pseudorange observation equations for N satellites, where N is an integer greater than or equal to 1.

5. The method according to claim 1, wherein The step of calculating the second Jacobian matrix and the third residual of the pseudorange observations and the standard time with respect to the terminal position to be solved, the receiver clock error, the deviation between the standard time and the current time of the terminal, and the time system deviation through the pseudorange observation equation includes: Calculate the pseudorange observation matrix based on the pseudorange observation equation; Based on the pseudorange observation matrix, take the derivatives of the terminal position to be solved, the receiver clock error, the deviation between the standard time and the current time of the terminal, and the time system deviation to obtain the second Jacobian matrix; Based on the pseudorange observations and the estimated values of the pseudorange observation matrix, determine the third residual.

6. The method according to claim 4, wherein Before determining the target terminal position according to the to-be-solved terminal position, the receiver clock drift, the receiver clock offset, and the deviation value between the standard time and the current moment of the terminal when the correction amount meets the iteration end condition, the method further includes: Optimizing the mathematical model of the pseudorange observation value based on the external time deviation to obtain the mathematical optimization model of the pseudorange observation value; Constructing a terminal time deviation correction equation for N satellites based on the mathematical optimization model of the pseudorange observation value; The calculating the second Jacobian matrix and the third residual of the pseudorange observation value and the standard time with respect to the to-be-solved terminal position, the receiver clock offset, the deviation value between the standard time and the current moment of the terminal, and the time system deviation through the pseudorange observation equation includes: Calculating the second Jacobian matrix and the third residual of the pseudorange observation value and the standard time with respect to the to-be-solved terminal position, the receiver clock offset, the deviation value between the standard time and the current moment of the terminal, and the time system deviation through the terminal time deviation correction equation.

7. The method according to claim 1, characterized in that Constructing the elevation constraint equation includes the following steps: Based on the elevation prior information, constructing the constraint condition between the terminal geodetic coordinates and the to-be-solved terminal position, the prior error of the terminal geodetic coordinates, and the prior error of the to-be-solved terminal position; Based on the constraint condition and the prior error of the terminal geodetic coordinates, performing Taylor series expansion on the prior error of the to-be-solved terminal position; Sorting out the Taylor series expansion to obtain the elevation constraint equation.

8. The method according to claim 1, characterized in that The calculating the parameter matrix and the first residual of the elevation information with respect to the to-be-solved terminal position through the elevation constraint equation includes: Calculating the elevation information based on the elevation constraint equation to obtain an elevation prediction matrix; Deriving the to-be-solved terminal position based on the elevation prediction matrix to obtain the parameter matrix; Determining the first residual based on the elevation information and the estimated value of the elevation prediction matrix.

9. The method according to claim 1, characterized in that, Constructing the Doppler observation equation includes the following steps: Constructing the mathematical model of the Doppler observation value based on the to-be-solved terminal position, the receiver clock drift, the wavelength of the satellite broadcast signal, and the speed of light in vacuum; Constructing the Doppler observation equation for N satellites based on the mathematical model of the Doppler measurement value.

10. The method according to claim 1, wherein Calculating the first Jacobian matrix and the second residual of the Doppler observation value with respect to the to-be-solved terminal position and the receiver clock drift through the Doppler observation equation includes: Calculating the Doppler observation value based on the Doppler observation equation to obtain a Doppler observation matrix; Deriving the to-be-solved terminal position and the receiver clock drift based on the Doppler observation matrix to obtain the first Jacobian matrix; Determining the second residual based on the Doppler observation value and the estimated value of the Doppler observation matrix.

11. The method according to claim 2, wherein When the iteration end condition is that the modulus of the correction amount is less than the correction threshold; when the correction amount meets the iteration end condition, determining the target terminal position according to the terminal position to be solved, the receiver clock drift, the receiver clock error, and the deviation value between the standard time and the current time of the terminal includes: When the modulus of the correction amount is less than the correction threshold, determining the target estimation parameters; Based on the receiver clock drift, the receiver clock error, and the deviation value between the standard time and the current time of the terminal in the target estimation parameters, calculating the terminal position to be solved to obtain the target terminal position.

12. The method according to claim 1, wherein The obtaining the elevation information corresponding to the approximate position of the terminal and the Doppler observation value of each satellite includes: Sending an elevation information acquisition request carrying the elevation information of the approximate position of the terminal to the regional elevation database server, so that the regional elevation database server collects the elevation information corresponding to the approximate position of the terminal according to the elevation information acquisition request; Receiving the elevation information broadcast by the regional elevation database server; Sending a satellite navigation ephemeris request to the continuously operating reference station CORS server, so that the CORS server queries the ephemeris data according to the satellite navigation ephemeris request; Receiving the full-system ephemeris data sent by the CORS server; Extracting the Doppler observation value from the full-system ephemeris data; The obtaining the pseudorange observation value of each satellite and the standard time includes: Extracting the pseudorange observation value corresponding to the approximate position of the terminal from the full-system ephemeris data and obtaining the standard time.

13. The method according to claim 12, characterized in that The obtaining the standard time includes: Sending a timing request to the timing system server, so that the timing system server queries the standard time according to the timing request; Receiving the standard time sent by the timing system server.

14. A device for determining the position of a terminal, characterized in that Includes: An acquisition unit, configured to acquire elevation information corresponding to the approximate position of the terminal and the Doppler observation value of each satellite; A processing unit, configured to calculate a parameter matrix and a first residual of the elevation information with respect to the terminal position to be solved through an elevation constraint equation; The processing unit is further configured to calculate a first Jacobian matrix and a second residual of the Doppler observation value with respect to the terminal position to be solved and the receiver clock drift through a Doppler observation equation; The acquisition unit is further configured to acquire the pseudorange observation value of each satellite and the standard time; The processing unit is further configured to calculate a second Jacobian matrix and a third residual of the pseudorange observation value and the standard time with respect to the terminal position to be solved, the receiver clock error, the deviation value between the standard time and the current time of the terminal, and the time system deviation through a pseudorange observation equation; The processing unit is further configured to calculate the partial derivative of the estimation parameter based on the parameter matrix, the first Jacobian matrix, and the second Jacobian matrix; Calculate a correction amount of the estimated parameters based on the partial derivatives, the weight matrix, the first residual, the second residual, and the third residual, where the estimated parameters include the terminal position to be solved, the receiver clock drift, the receiver clock offset, and the deviation value between the standard time and the current time of the terminal; A determination unit, configured to determine a target terminal position according to the terminal position to be solved and the receiver clock drift when the correction amount satisfies an iteration end condition.

15. The determination device according to claim 14, wherein Specifically, the determination unit is configured to determine the target terminal position according to the terminal position to be solved, the receiver clock drift, the receiver clock offset, and the deviation value between the standard time and the current time of the terminal when the correction amount satisfies the iteration end condition.

16. The determining device according to claim 14, wherein The processing unit is further configured to calculate the weight matrix based on the elevation angle of each satellite and the signal-to-noise ratio of the pseudorange observation value.

17. The determination device according to claim 15, characterized in that, Specifically, the processing unit is configured to: Construct a mathematical model of the pseudorange observation value based on the terminal position to be solved, the receiver clock offset, the deviation value between the standard time and the current time of the terminal, the error correction number, and the speed of light in vacuum; Construct the pseudorange observation equation for N satellites based on the mathematical model of the pseudorange observation value, where N is an integer greater than or equal to 1.

18. The determination device according to claim 14, characterized in that, Specifically, the processing unit is configured to: Calculate the pseudorange observation matrix by calculating the pseudorange observation value based on the pseudorange observation equation; Derive the second Jacobian matrix for the terminal position to be solved, the receiver clock offset, the deviation value between the standard time and the current time of the terminal, and the time system deviation based on the pseudorange observation matrix; Determine the third residual based on the pseudorange observation value and the estimated value of the pseudorange observation matrix.

19. The determination device according to claim 17, characterized in that, Specifically, the processing unit is configured to: Optimize the mathematical model of the pseudorange observation value based on the external time deviation to obtain a mathematical optimization model of the pseudorange observation value; Construct a terminal time deviation correction equation for N satellites based on the mathematical optimization model of the pseudorange observation value; Specifically, the processing unit is further configured to: Calculate the second Jacobian matrix and the third residual of the pseudorange observation value and the standard time with respect to the terminal position to be solved, the receiver clock offset, the deviation value between the standard time and the current time of the terminal, and the time system deviation through the terminal time deviation correction equation.

20. The determination device according to claim 14, characterized in that, Specifically, the processing unit is configured to: Construct a constraint condition between the terminal geodetic coordinates and the terminal position to be solved, the prior error of the terminal geodetic coordinates, and the prior error of the terminal position to be solved based on the elevation prior information; Perform a Taylor series expansion on the prior error of the terminal position to be solved based on the constraint condition and the prior error of the terminal geodetic coordinates; Arrange the Taylor series expansion to obtain the elevation constraint equation.

21. The determining device according to claim 14, characterized in that, Specifically, the processing unit is configured to: Calculate the elevation prediction matrix based on the elevation constraint equation; Derive the parameter matrix for the terminal position to be solved based on the elevation prediction matrix; Determine the first residual based on the elevation information and the estimated value of the elevation prediction matrix.

22. The determination device according to claim 14, wherein The processing unit is specifically configured to: Construct a mathematical model of the Doppler observation value based on the to-be-solved terminal position, the receiver clock drift, the wavelength of the satellite broadcast signal, and the speed of light value in vacuum; Construct the Doppler observation equation for N satellites based on the mathematical model of the Doppler measurement value.

23. The determination device according to claim 14, characterized in that The processing unit is specifically configured to: Calculate the Doppler observation value based on the Doppler observation equation to obtain a Doppler observation matrix; Derive the first Jacobian matrix for the to-be-solved terminal position and the receiver clock drift based on the Doppler observation matrix; Determine the second residual based on the Doppler observation value and the estimated value of the Doppler observation matrix.

24. The determination device according to claim 15, characterized in that, The processing unit is specifically configured to: Determine the target estimated parameter when the norm of the correction amount is less than the correction threshold; Solve the to-be-solved terminal position based on the receiver clock drift, the receiver clock error, and the deviation value between the standard time and the current time of the terminal in the target estimated parameter to obtain the target terminal position.

25. The determination device according to claim 14, characterized in that The obtaining unit is specifically configured to: Send an elevation information acquisition request carrying the approximate position of the terminal to the regional elevation database server, so that the regional elevation database server collects the elevation information corresponding to the approximate position of the terminal according to the elevation information acquisition request; Receive the elevation information broadcast by the regional elevation database server; Send a satellite navigation ephemeris request to the continuously operating reference station CORS server, so that the CORS server queries the ephemeris data according to the satellite navigation ephemeris request; Receive the full-system ephemeris data sent by the CORS server; Extract the Doppler observation value from the full-system ephemeris data; The obtaining unit is specifically configured to: Extract the pseudorange observation value corresponding to the approximate position of the terminal from the full-system ephemeris data and obtain the standard time.

26. The determining device according to claim 25, characterized in that The obtaining unit is specifically configured to: Send a timing request to the timing system server, so that the timing system server queries the standard time according to the timing request; Receive the standard time sent by the timing system server.

27. A computer device, comprising a memory, a processor, and a bus system, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 13; The bus system is used to connect the memory and the processor, so that the memory and the processor communicate with each other.

28. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the method according to any one of claims 1 to 13.

29. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the method according to any one of claims 1 to 13.

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