A single-frequency GNSS unmanned aerial vehicle positioning method, device, medium and product

Abstract

The present application discloses a single-frequency GNSS unmanned aerial vehicle positioning method, device, medium and product, which relates to the field of unmanned aerial vehicle positioning. At any current moment: the distance and ionospheric delay of each satellite are determined based on the position coordinates of each satellite and the position coordinates of the unmanned aerial vehicle at the previous moment; the tropospheric delay at the current moment is determined based on environmental parameters; three satellites are determined as first target satellites, and two satellites are determined as second target satellites; pseudo-range observation values ​​are calculated based on the distance, corrected clock error data, ionospheric delay and tropospheric delay of each first target satellite; phase observation values ​​are calculated based on the distance, corrected clock error data, ionospheric delay, carrier phase integer ambiguity and tropospheric delay of each second target satellite; the position coordinates of the unmanned aerial vehicle are determined based on the pseudo-range observation values ​​and position coordinates of each first target satellite, and the phase observation values ​​and position coordinates of each second target satellite. The present application improves the accuracy of unmanned aerial vehicle positioning and reduces costs.

Description

Technical Field

[0001] The present application relates to the field of UAV positioning technology, and in particular to a single-frequency GNSS UAV positioning method, device, medium and product. Background Art

[0002] The Global Navigation Satellite System (GNSS) has become an indispensable part of modern society and has been widely used in all walks of life. However, as people's demand for positioning accuracy continues to increase, the accuracy of standard positioning services can no longer meet the needs of precise positioning. The accuracy of standard positioning services provided by GNSS is generally between tens of meters and meters, but for some application scenarios, such as precision agriculture, surveying and mapping, and autonomous driving, higher-precision positioning services are required.

[0003] In order to achieve real-time precise positioning, two main technical means are currently used: satellite-based augmentation and ground-based augmentation. Ground-based augmentation is achieved by laying a dense network of reference stations on the ground. The range of a single reference station is generally around 20 kilometers. Therefore, its high-precision positioning service depends on the dense deployment of reference stations, which makes it difficult to achieve high-precision positioning services in open areas such as the ocean. Satellite-based augmentation, on the other hand, uses a regional or global tracking station network to calculate the precise orbit and clock corrections of the satellite, and transmits these corrections to users in real time via communication satellites. Users use the correction information broadcast by satellites and use a linear combination method to eliminate the influence of the ionosphere, thereby achieving real-time centimeter-level dynamic positioning accuracy.

[0004] However, due to the single-frequency nature of GNSS receivers, changes in the ionosphere can cause changes in signal propagation speed, thus affecting the positioning accuracy of drones. However, high-precision positioning methods usually require additional communication links and ground differential stations, which increases costs and complexity. Summary of the invention

[0005] The purpose of this application is to provide a single-frequency GNSS UAV positioning method, device, medium and product, which improves the accuracy of UAV positioning and reduces the cost.

[0006] To achieve the above objectives, this application provides the following solutions:

[0007] In a first aspect, the present application provides a single-frequency GNSS UAV positioning method, comprising:

[0008] Obtaining the current environmental parameters and the position coordinates and corrected clock error data of each satellite; the satellite is a geosynchronous orbit satellite in the Beidou satellite system;

[0009] Based on the position coordinates of each satellite at the current moment and the position coordinates of the drone at the previous moment, the distance of the corresponding satellite at the current moment is calculated; the distance of the satellite is the geometric distance between the satellite and the drone's receiver; the position coordinates of the drone at the initial moment are determined by single-point positioning;

[0010] Based on the position coordinates of all satellites at the current moment, the position coordinates of the drone at the previous moment and the Klobuchar model, the ionospheric delay at the current moment is determined;

[0011] Based on the environmental parameters at the current moment, determining the tropospheric delay at the current moment;

[0012] Determine three satellites as first target satellites and determine two satellites as second target satellites; calculate the pseudorange observation value of the first target satellite at the current moment based on the distance of each of the first target satellites at the current moment, the corrected clock error data, the ionospheric delay and the tropospheric delay; the pseudorange observation value of the first target satellite is the pseudorange observation value between the first target satellite and the receiver;

[0013] The phase observation value of the corresponding second target satellite at the current moment is calculated based on the distance of each second target satellite at the current moment, the corrected clock error data, the ionospheric delay, the carrier phase integer ambiguity and the tropospheric delay respectively; the carrier phase integer ambiguity of the second target satellite at the current moment is determined by the phase observation value of the second target satellite at the previous moment, and the phase observation value of the second target satellite is the carrier phase observation value between the second target satellite and the receiver;

[0014] Based on the pseudorange observation values ​​and position coordinates of all the first target satellites at the current moment and the phase observation values ​​and position coordinates of all the second target satellites at the current moment, the position coordinates of the UAV at the current moment are determined.

[0015] Optionally, based on the position coordinates of each satellite at the current moment and the position coordinates of the drone at the previous moment, the distance of the corresponding satellite at the current moment is calculated, including:

[0016] Determine any satellite as the current satellite;

[0017] The distance calculation formula is used to calculate the distance of the corresponding satellite at the current moment according to the position coordinates of each satellite at the current moment and the position coordinates of the drone at the previous moment; the distance calculation formula is:

[0018] ;

[0019] in, For the The moment The geometric distance between the satellites and the drone’s receiver; For the The moment The X-axis component of the satellite's position coordinates; For the The X-axis component of the drone's position coordinates at the moment; For the The moment The Y-axis component of the satellite's position coordinates; For the The Y-axis component of the drone's position coordinates at the moment; For the The moment The Z-axis component of the satellite's position coordinates; For the The Z-axis component of the drone's position coordinates at that moment.

[0020] Optionally, the environmental parameters include: sea level atmospheric pressure, zenith distance, temperature and water vapor pressure;

[0021] Based on the current environmental parameters, the current tropospheric delay is determined, including:

[0022] Calculate the dry delay at the current moment according to the sea level atmospheric pressure and zenith distance at the current moment;

[0023] Calculate the wet delay at the current moment according to the zenith distance, temperature and water vapor pressure at the current moment;

[0024] Calculate the tropospheric delay at the current moment based on the dry delay and wet delay at the current moment.

[0025] Optionally, calculating the pseudorange observation value of the corresponding first target satellite at the current moment based on the distance of each of the first target satellites at the current moment, the corrected clock error data, the ionospheric delay, and the tropospheric delay, respectively, includes:

[0026] Determine any first target satellite as the current first target satellite;

[0027] The pseudorange observation equation is used to calculate the pseudorange observation value of the current first target satellite at the current moment based on the distance of the current first target satellite at the current moment, the corrected clock error data, the ionospheric delay and the tropospheric delay; the pseudorange observation equation is:

[0028] ;

[0029] in, For the The moment Pseudorange observations of satellites; is the speed of light; is the clock error data of the receiver; For the The moment Corrected clock error data of satellites; For the Ionospheric delay at time For the Tropospheric delay at time; is the pseudorange observation noise.

[0030] Optionally, calculating the phase observation value of the corresponding second target satellite at the current moment based on the distance of each of the second target satellites at the current moment, the corrected clock error data, the ionospheric delay, the carrier phase integer ambiguity and the tropospheric delay, respectively, includes:

[0031] determining any second target satellite as a current second target satellite;

[0032] The phase observation equation is used to calculate the phase observation value of the current second target satellite at the current moment according to the distance of the current second target satellite at the current moment, the corrected clock error data, the ionospheric delay, the carrier phase integer ambiguity and the tropospheric delay; the phase observation equation is:

[0033] ;

[0034] in, For the The moment The phase observations of satellites; For the The moment The carrier phase integer ambiguity of the satellites; is the satellite signal wavelength; is the carrier phase observation noise.

[0035] Optionally, determining the position coordinates of the UAV at the current moment based on the pseudorange observation values ​​and position coordinates of all the first target satellites at the current moment and the phase observation values ​​and position coordinates of all the second target satellites at the current moment includes:

[0036] Using the positioning equation, the position coordinates of the UAV at the current moment are determined according to the pseudorange observation values ​​and position coordinates of all the first target satellites at the current moment and the phase observation values ​​and position coordinates of all the second target satellites; the positioning equation includes:

[0037] ;

[0038] ;

[0039] ;

[0040] ;

[0041] in, For the The vector of observations at time instant; For the The design matrix of the moment; For the The parameter vector to be solved at time t; For the The observation noise vector at time t; For the The pseudorange observation value of the first satellite at time; For the The X-axis component of the position coordinates of the first satellite at time; For the The Y-axis component of the position coordinates of the first satellite at time; For the The Z-axis component of the position coordinates of the first satellite at time; For the The pseudorange observation value of the second satellite at time; For the The X-axis component of the position coordinates of the second satellite at time; For the The Y-axis component of the position coordinates of the second satellite at time; For the The Z-axis component of the position coordinates of the second satellite at time; For the The pseudorange observation value of the third satellite at time; For the The X-axis component of the position coordinates of the third satellite at time; For the The Y-axis component of the position coordinates of the third satellite at time; For the The Z-axis component of the position coordinates of the third satellite at time; For the The phase observation value of the 4th satellite at time; For the The X-axis component of the position coordinates of the fourth satellite at time; For the The Y-axis component of the position coordinates of the fourth satellite at time; For the The Z-axis component of the position coordinates of the fourth satellite at time; For the The phase observation value of the 5th satellite at time; For the The X-axis component of the position coordinates of the 5th satellite at time; For the The Y-axis component of the position coordinates of the 5th satellite at time; For the The Z-axis component of the position coordinates of the 5th satellite at time; For the The X-axis component of the drone's position coordinates at the moment; For the The Y-axis component of the drone's position coordinates at the moment; For the The Z-axis component of the drone's position coordinates at the moment; For the The first ambiguity value at time instant; For the The second ambiguity value at time instant.

[0042] In a second aspect, the present application provides a computer device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement any of the single-frequency GNSS UAV positioning methods described above.

[0043] In a third aspect, the present application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements any of the single-frequency GNSS UAV positioning methods described above.

[0044] In a fourth aspect, the present application provides a computer program product, including a computer program, which, when executed by a processor, implements the single-frequency GNSS UAV positioning method described in any one of the above items.

[0045] According to the specific embodiments provided in this application, this application discloses the following technical effects:

[0046] This application discloses a single-frequency GNSS UAV positioning method, device, medium and product. By determining the ionospheric delay, it solves the problem that due to the single frequency of the GNSS receiver, the change of the ionosphere will cause the change of the signal propagation speed, affecting the positioning accuracy, and improves the accuracy of UAV positioning; and no additional communication links and ground differential stations are required, and the UAV positioning is directly performed using the satellite position coordinates and the corrected clock error data, which reduces the cost. Specifically including:

[0047] 1. This application does not require dual-frequency receivers, additional communication links or ground differential stations. This greatly reduces equipment costs and operation and maintenance costs, making high-precision positioning technology more economical and suitable for a wide range of application scenarios. Simple hardware requirements: Only a single-frequency GNSS receiver is required, the equipment structure is simple and easy to maintain.

[0048] 2. The orbit and clock errors are corrected by PPP-B2b enhanced information, and the processing method of ionospheric parameter constraints is used to achieve centimeter-level high-precision real-time positioning. The ionospheric parameters are converted into estimable quantities using the reference conversion method, and the ionospheric delay is estimated and deducted in real time using single-frequency observation data, which improves the positioning accuracy.

[0049] 3. This application can receive and process GNSS signals in real time, perform real-time orbit, clock error and ionospheric delay correction, provide instant high-precision positioning results, and meet real-time application requirements. Since it does not need to rely on external differential station data, the system responds quickly and the positioning results can be updated quickly.

[0050] 4. The system does not rely on external communication links for differential data transmission, which enhances the independence and reliability of the system. There is no need to deploy and maintain ground differential stations, which simplifies the system architecture and reduces infrastructure dependence.

[0051] 5. Since the system does not rely on external differential stations, it is suitable for various complex environments and different geographical areas and has a wider applicability.

[0052] 6. Through real-time orbit and clock correction, as well as estimation and deduction of ionospheric delay, the system can provide stable high-precision positioning services in various environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0054] Figure 1 A schematic diagram of the flow of a single-frequency GNSS UAV positioning method provided in one embodiment of the present application.

[0055] Figure 2 Flowchart of the single-frequency GNSS UAV positioning method enhanced for PPP-B2b.

[0056] Figure 3 A schematic diagram of the structure of a computer device provided in one embodiment of the present application. DETAILED DESCRIPTION

[0057] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0058] The purpose of this application is to provide a single-frequency GNSS UAV positioning method, device, medium and product, aiming to improve the accuracy of UAV positioning and reduce costs.

[0059] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0060] In an exemplary embodiment, Figure 1 and Figure 2 As shown, the single-frequency GNSS UAV positioning method in this embodiment includes:

[0061] Step 1: Obtain the current environmental parameters, the position coordinates of each satellite, and the corrected clock error data; the satellite is a geosynchronous orbit satellite in the Beidou satellite system.

[0062] Specifically, Precise Point Positioning B2b (PPP-B2b) technology broadcasts position coordinates and clock corrections in real time via geosynchronous orbit (GEosynchronous Orbit, GEO) satellites to provide high-precision positioning data.

[0063] The BeiDou satellite system includes multiple GEO satellites that can continuously broadcast PPP-B2b correction information in real time. The correction includes position coordinates and clock corrections, so it can significantly improve the positioning accuracy of drones without the help of ground signal stations.

[0064] The drone receives the PPP-B2b correction information from the BeiDou-3 GEO satellite and extracts its position coordinates and corrected clock error data.

[0065] Step 2: Calculate the distance to the corresponding satellite at the current moment based on the position coordinates of each satellite at the current moment and the position coordinates of the drone at the previous moment.

[0066] As an optional implementation, step 2 includes:

[0067] Step 21: Determine any satellite as the current satellite.

[0068] Step 22: Use the distance calculation formula to calculate the distance of the corresponding satellite at the current moment according to the position coordinates of each satellite at the current moment and the position coordinates of the drone at the previous moment; the distance calculation formula is:

[0069] .

[0070] in, For the The moment The geometric distance between the satellites and the drone’s receiver; For the The moment The X-axis component of the satellite's position coordinates; For the The X-axis component of the drone's position coordinates at the moment; For the The moment The Y-axis component of the satellite's position coordinates; For the The Y-axis component of the drone's position coordinates at the moment; For the The moment The Z-axis component of the satellite's position coordinates; For the The Z-axis component of the drone's position coordinates at that moment.

[0071] Among them, the distance of the satellite is the geometric distance between the satellite and the receiver of the UAV; the position coordinates of the UAV at the initial moment are determined by single-point positioning.

[0072] Step 3: Based on the position coordinates of all satellites at the current moment, the position coordinates of the drone at the previous moment, and the Klobuchar model, determine the ionospheric delay at the current moment.

[0073] Specifically, the ionosphere is a region of densely charged particles in the Earth's atmosphere, which has a significant impact on the propagation speed of GNSS signals. Ionospheric delay is one of the main sources of delay in GNSS single-frequency positioning, so it is necessary to determine the ionospheric delay. The steps for determining the ionospheric delay specifically include: (1) obtaining ionospheric parameters through Klobuchar model parameters; (2) calculating the ionospheric puncture point at the current moment based on the position coordinates of all satellites at the current moment and the position coordinates of the drone at the previous moment; (3) using the Klobuchar model and the geographic coordinates of the ionospheric puncture point at the current moment, calculate the ionospheric delay at the current moment.

[0074] Step 4: Based on the environmental parameters at the current moment, determine the tropospheric delay at the current moment.

[0075] As an optional implementation, the environmental parameters include: sea level atmospheric pressure, zenith distance, temperature and water vapor pressure.

[0076] Step 4 includes:

[0077] Step 41: Calculate the dry delay at the current moment according to the sea level atmospheric pressure and the zenith distance at the current moment.

[0078] Step 42: Calculate the wet delay at the current moment according to the zenith distance, temperature and water vapor pressure at the current moment.

[0079] Step 43: Calculate the tropospheric delay at the current moment according to the dry delay and wet delay at the current moment.

[0080] Specifically, tropospheric delay refers to the delay effect that GNSS signals experience when passing through the troposphere, which causes measurement delay. The troposphere is the layer of the Earth's atmosphere closest to the ground, containing most of the water vapor and air mass, which has a significant impact on the propagation of GNSS signals.

[0081] Step 5: Determine 3 satellites as the first target satellites and determine 2 satellites as the second target satellites.

[0082] Step 6: Calculate the pseudorange observation value of the corresponding first target satellite at the current moment based on the distance of each first target satellite at the current moment, the corrected clock error data, the ionospheric delay and the tropospheric delay.

[0083] The pseudo-range observation value of the first target satellite is a pseudo-range observation value between the first target satellite and the receiver.

[0084] As an optional implementation, step 6 includes:

[0085] Step 61: Determine any first target satellite as the current first target satellite.

[0086] Step 62: Using the pseudorange observation equation, based on the distance of the current first target satellite at the current moment, the corrected clock error data, the ionospheric delay and the tropospheric delay, the pseudorange observation value of the current first target satellite at the current moment is calculated; the pseudorange observation equation is:

[0087] .

[0088] in, For the The moment Pseudorange observations of satellites; is the speed of light; is the clock error data of the receiver; For the The moment Corrected clock error data of satellites; For the Ionospheric delay at time For the Tropospheric delay at time; is the pseudorange observation noise.

[0089] Step 7: Calculate the phase observation value of the corresponding second target satellite at the current moment based on the distance of each second target satellite at the current moment, the corrected clock error data, the ionospheric delay, the carrier phase integer ambiguity and the tropospheric delay.

[0090] Among them, the carrier phase integer ambiguity of the second target satellite at the current moment is determined by the phase observation value of the second target satellite at the previous moment, and the phase observation value of the second target satellite is the carrier phase observation value between the second target satellite and the receiver.

[0091] As an optional implementation, step 7 includes:

[0092] Step 71: Determine any second target satellite as the current second target satellite.

[0093] Step 72: Using the phase observation equation, the phase observation value of the current second target satellite at the current moment is calculated according to the distance of the current second target satellite at the current moment, the corrected clock error data, the ionospheric delay, the carrier phase integer ambiguity and the tropospheric delay; the phase observation equation is:

[0094] .

[0095] in, For the The moment The phase observations of satellites; For the The moment The carrier phase integer ambiguity of the satellites; is the satellite signal wavelength; is the carrier phase observation noise.

[0096] Step 8: Based on the pseudo-range observation values ​​and position coordinates of all first target satellites at the current moment and the phase observation values ​​and position coordinates of all second target satellites at the current moment, determine the position coordinates of the UAV at the current moment.

[0097] As an optional implementation, step 8 includes:

[0098] Using the positioning equation, the current position coordinates of the UAV are determined based on the pseudo-range observation values ​​and position coordinates of all first target satellites and the phase observation values ​​and position coordinates of all second target satellites; the positioning equation includes:

[0099] .

[0100] .

[0101] .

[0102] .

[0103] in, For the The vector of observations at time instant; For the The design matrix of the moment; For the The parameter vector to be solved at time t; For the The observation noise vector at time t; For the The pseudorange observation value of the first satellite at time; For the The X-axis component of the position coordinates of the first satellite at time; For the The Y-axis component of the position coordinates of the first satellite at time; For the The Z-axis component of the position coordinates of the first satellite at time; For the The pseudorange observation value of the second satellite at time; For the The X-axis component of the position coordinates of the second satellite at time; For the The Y-axis component of the position coordinates of the second satellite at time; For the The Z-axis component of the position coordinates of the second satellite at time; For the The pseudorange observation value of the third satellite at time; For the The X-axis component of the position coordinates of the third satellite at time; For the The Y-axis component of the position coordinates of the third satellite at time; For the The Z-axis component of the position coordinates of the third satellite at time; For the The phase observation value of the 4th satellite at time; For the The X-axis component of the position coordinates of the fourth satellite at time; For the The Y-axis component of the position coordinates of the fourth satellite at time; For the The Z-axis component of the position coordinates of the fourth satellite at time; For the The phase observation value of the 5th satellite at time; For the The X-axis component of the position coordinates of the 5th satellite at time; For the The Y-axis component of the position coordinates of the 5th satellite at time; For the The Z-axis component of the position coordinates of the 5th satellite at time; For the The X-axis component of the drone's position coordinates at the moment; For the The Y-axis component of the drone's position coordinates at the moment; For the The Z-axis component of the drone's position coordinates at the moment; For the The first ambiguity value at time instant; For the The second ambiguity value at time instant.

[0104] In an exemplary embodiment, a computer device is provided, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement a single-frequency GNSS UAV positioning method.

[0105] In an exemplary embodiment, a computer-readable storage medium is provided, on which a computer program is stored, and when the computer program is executed by a processor, a single-frequency GNSS UAV positioning method is implemented.

[0106] In an exemplary embodiment, a computer program product is provided, comprising a computer program, which implements a single-frequency GNSS UAV positioning method when executed by a processor.

[0107] In an exemplary embodiment, a computer device is provided. The computer device may be a server or a terminal. The internal structure diagram thereof may be as follows: Figure 3As shown. The computer device includes a processor, a memory, an input / output interface (Input / Output, referred to as I / O) and a communication interface. Among them, the processor, the memory and the input / output interface are connected through a system bus, and the communication interface is connected to the system bus through the input / output interface. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a single-frequency GNSS unmanned aerial vehicle positioning method is implemented.

[0108] Those skilled in the art will understand that Figure 3 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0109] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant regulations.

[0110] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM may be in various forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM).

[0111] The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. The non-relational database may include a distributed database based on blockchain, etc., but is not limited thereto. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but is not limited thereto.

[0112] The technical features of the above embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0113] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A single-frequency GNSS UAV positioning method, characterized in that: The single-frequency GNSS UAV positioning method comprises: Obtaining the current environmental parameters and the position coordinates and corrected clock error data of each satellite; the satellite is a geosynchronous orbit satellite in the Beidou satellite system; Based on the position coordinates of each satellite at the current moment and the position coordinates of the drone at the previous moment, the distance of the corresponding satellite at the current moment is calculated; the distance of the satellite is the geometric distance between the satellite and the drone's receiver; the position coordinates of the drone at the initial moment are determined by single-point positioning; Based on the position coordinates of all satellites at the current moment, the position coordinates of the drone at the previous moment and the Klobuchar model, the ionospheric delay at the current moment is determined; Based on the environmental parameters at the current moment, determining the tropospheric delay at the current moment; Determine three satellites as first target satellites and determine two satellites as second target satellites; calculate the pseudorange observation value of the first target satellite at the current moment based on the distance of each of the first target satellites at the current moment, the corrected clock error data, the ionospheric delay and the tropospheric delay; the pseudorange observation value of the first target satellite is the pseudorange observation value between the first target satellite and the receiver; The phase observation value of the corresponding second target satellite at the current moment is calculated based on the distance of each second target satellite at the current moment, the corrected clock error data, the ionospheric delay, the carrier phase integer ambiguity and the tropospheric delay respectively; the carrier phase integer ambiguity of the second target satellite at the current moment is determined by the phase observation value of the second target satellite at the previous moment, and the phase observation value of the second target satellite is the carrier phase observation value between the second target satellite and the receiver; Determine the position coordinates of the UAV at the current moment based on the pseudorange observation values ​​and position coordinates of all the first target satellites at the current moment and the phase observation values ​​and position coordinates of all the second target satellites; Based on the position coordinates of each satellite at the current moment and the position coordinates of the drone at the previous moment, the distance of the corresponding satellite at the current moment is calculated, including: Determine any satellite as the current satellite; The distance calculation formula is used to calculate the distance of the corresponding satellite at the current moment according to the position coordinates of each satellite at the current moment and the position coordinates of the drone at the previous moment; the distance calculation formula is: ； in, For the The moment The geometric distance between the satellites and the drone’s receiver; For the The moment The X-axis component of the satellite's position coordinates; For the The X-axis component of the drone's position coordinates at the moment; For the The moment The Y-axis component of the satellite's position coordinates; For the The Y-axis component of the drone's position coordinates at the moment; For the The moment The Z-axis component of the satellite's position coordinates; For the The Z-axis component of the drone's position coordinates at the moment; Calculating the pseudorange observation value of the corresponding first target satellite at the current moment based on the distance of each of the first target satellites at the current moment, the corrected clock error data, the ionospheric delay, and the tropospheric delay, including: Determine any first target satellite as the current first target satellite; The pseudorange observation equation is used to calculate the pseudorange observation value of the current first target satellite at the current moment based on the distance of the current first target satellite at the current moment, the corrected clock error data, the ionospheric delay and the tropospheric delay; the pseudorange observation equation is: ； in, For the The moment Pseudorange observations of satellites; is the speed of light; is the clock error data of the receiver; For the The moment Corrected clock error data of satellites; For the Ionospheric delay at time For the Tropospheric delay at time; is the pseudorange observation noise; Calculating the phase observation value of the corresponding second target satellite at the current moment based on the distance of each of the second target satellites at the current moment, the corrected clock error data, the ionospheric delay, the carrier phase integer ambiguity and the tropospheric delay, including: determining any second target satellite as a current second target satellite; The phase observation equation is used to calculate the phase observation value of the current second target satellite at the current moment according to the distance of the current second target satellite at the current moment, the corrected clock error data, the ionospheric delay, the carrier phase integer ambiguity and the tropospheric delay; the phase observation equation is: ； in, For the The moment The phase observations of satellites; For the The moment The carrier phase integer ambiguity of the satellites; is the satellite signal wavelength; is the carrier phase observation noise; Determining the position coordinates of the UAV at the current moment based on the pseudorange observation values ​​and position coordinates of all the first target satellites at the current moment and the phase observation values ​​and position coordinates of all the second target satellites at the current moment includes: Using the positioning equation, the position coordinates of the UAV at the current moment are determined according to the pseudorange observation values ​​and position coordinates of all the first target satellites at the current moment and the phase observation values ​​and position coordinates of all the second target satellites; the positioning equation includes: ； ； ； ； in, For the The vector of observations at time instant; For the The design matrix of the moment; For the The parameter vector to be solved at time t; For the The observation noise vector at time t; For the The pseudorange observation value of the first satellite at time; For the The X-axis component of the position coordinates of the first satellite at time; For the The Y-axis component of the position coordinates of the first satellite at time; For the The Z-axis component of the position coordinates of the first satellite at time; For the The pseudorange observation value of the second satellite at time; For the The X-axis component of the position coordinates of the second satellite at time; For the The Y-axis component of the position coordinates of the second satellite at time; For the The Z-axis component of the position coordinates of the second satellite at time; For the The pseudorange observation value of the third satellite at time; For the The X-axis component of the position coordinates of the third satellite at time; For the The Y-axis component of the position coordinates of the third satellite at time; For the The Z-axis component of the position coordinates of the third satellite at time; For the The phase observation value of the 4th satellite at time; For the The X-axis component of the position coordinates of the fourth satellite at time; For the The Y-axis component of the position coordinates of the fourth satellite at time; For the The Z-axis component of the position coordinates of the fourth satellite at time; For the The phase observation value of the 5th satellite at time; For the The X-axis component of the position coordinates of the 5th satellite at time; For the The Y-axis component of the position coordinates of the 5th satellite at time; For the The Z-axis component of the position coordinates of the 5th satellite at time; For the The X-axis component of the drone's position coordinates at the moment; For the The Y-axis component of the drone's position coordinates at the moment; For the The Z-axis component of the drone's position coordinates at the moment; For the The first ambiguity value at time instant; For the The second ambiguity value at time instant.

2. The single-frequency GNSS UAV positioning method according to claim 1, characterized in that: The environmental parameters include: sea level atmospheric pressure, zenith distance, temperature and water vapor pressure; Based on the current environmental parameters, the current tropospheric delay is determined, including: Calculate the dry delay at the current moment according to the sea level atmospheric pressure and zenith distance at the current moment; Calculate the wet delay at the current moment according to the zenith distance, temperature and water vapor pressure at the current moment; Calculate the tropospheric delay at the current moment based on the dry delay and wet delay at the current moment.

3. A computer device comprising: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the single-frequency GNSS UAV positioning method described in any one of claims 1-2.

4. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the single-frequency GNSS UAV positioning method described in any one of claims 1-2 is implemented.

5. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the single-frequency GNSS UAV positioning method described in any one of claims 1-2 is implemented.

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