Network RTK method for generating virtual reference stations based on PPP SSR corrections

Abstract

This application relates to the technical field of global satellite navigation systems, and particularly to a network RTK method for generating a virtual reference station based on PPP SSR corrections. The method includes: calculating the approximate coordinates of a target rover station, and using the approximate coordinates of the rover station and the PPP SSR information of multiple target satellites by a target server to correct the observation value errors of each target satellite, and generating the position coordinates and observation values of the virtual reference station; based on the RTCM protocol, enabling the target server to encode the position coordinates and observation values to obtain the OSR information corresponding to the position coordinates and observation values, and broadcasting the OSR information to the target rover station; based on the OSR information and the double-difference relative positioning strategy, enabling the target rover station to obtain the relative position information between the target rover station and the virtual reference station, so as to determine the position coordinates of the target rover station. Thus, the problems of slow convergence, limited coverage, and poor receiver compatibility in the existing navigation and positioning technologies are solved.

Description

Technical Field

[0001] The present application relates to the technical field of global satellite navigation systems, and particularly to a network RTK method for generating a virtual reference station based on PPP SSR corrections. Background Art

[0002] The Global Navigation Satellite System (GNSS) can provide high-precision distance observation values, achieving real-time navigation and positioning accuracy from centimeters to sub-meters, which is essential for intelligent transportation. In an open observation environment, the GNSS navigation and positioning accuracy without external correction services reaches 10 m, and the accuracy cannot meet the requirements of intelligent transportation applications. Therefore, it is necessary to eliminate GNSS observation errors to further improve the positioning accuracy, such as orbit and clock errors, hardware biases, and atmospheric delays.

[0003] The Virtual Reference Stations (VRS) technology virtually translates the actual observations of the master reference station to near the rover station, virtually generates a reference station, broadcasts the generated virtual observations or error correction signals with high precision to the rover station, forms an ultra-short baseline, and thus obtains a high-precision positioning result. The VRS technology has a wide coverage range, high positioning accuracy, and strong reliability, and has become a hot spot in precise positioning research.

[0004] However, when the distance of the rover station exceeds the coverage range of the reference station, differential dynamic positioning needs to re-determine a new reference station. The real-time PPP (Precise Point Positioning) technology achieves high-precision positioning by receiving correction information in the State Space Representation (SSR) format. The SSR correction information includes observation errors such as orbit, clock error, pseudorange bias, and atmospheric delay, and is broadcast free of charge to global users by the IGS (International GNSS Service) organization. Currently, commercially available receivers can receive RTCM (Radio Technical Commission for Maritime) OSR (Observation Space Representation) information, and most do not receive RTCM SSR. Although the next-generation receivers start to use RTCM SSR, the existing receivers can only receive RTCM OSR.

[0005] In summary, the existing navigation and positioning technologies have a slow convergence speed, limited coverage range, and poor receiver compatibility, and urgent solutions are needed. Summary of the Invention

[0006] The present application provides a network RTK method for generating a virtual reference station based on PPP SSR corrections to solve problems such as slow convergence speed, limited coverage, and poor receiver compatibility in existing navigation and positioning technologies.

[0007] The first aspect of the embodiments of the present application provides a network RTK method for generating a virtual reference station based on PPP SSR corrections, including the following steps: calculating the approximate coordinates of the rover of the target rover station, and using the approximate coordinates of the rover and the PPP SSR information of multiple target satellites by the target server to correct the observation value errors of each target satellite among the multiple target satellites, so as to generate the position coordinates and observation values of the virtual reference station; based on the preset RTCM protocol, enabling the target server to encode the position coordinates and the observation values to obtain the OSR information corresponding to the position coordinates and the observation values, and broadcasting the OSR information to the target rover station; based on the OSR information and the preset double-difference relative positioning strategy, enabling the target rover station to obtain the relative position information between the target rover station and the virtual reference station, and determining the position coordinates of the target rover station according to the relative position information.

[0008] Optionally, in an embodiment of the present application, the calculating the approximate coordinates of the rover of the target rover station, and using the approximate coordinates of the rover and the PPP SSR information of multiple target satellites by the target server to correct the observation value errors of each target satellite among the multiple target satellites, so as to generate the position coordinates and observation values of the virtual reference station includes: receiving the observation values and broadcast ephemeris of the multiple target satellites by the target rover station, and constructing an observation equation corresponding to the target rover station according to the observation values and broadcast ephemeris of the multiple target satellites; calculating the approximate coordinates of the rover of the target rover station based on the preset SPP positioning strategy, and correcting the satellite orbit error, satellite clock error, and ionospheric slant delay error of the target satellite by the target server according to the observation equation, the approximate coordinates of the rover, and the PPP SSR information, so as to obtain the position coordinates and observation values of the virtual reference station.

[0009] Optionally, in an embodiment of the present application, based on the OSR information and a preset double-difference relative positioning strategy, enabling the target rover to obtain the relative position information between the target rover and the virtual reference station includes: constructing a double-difference observation equation according to the OSR information and the double-difference relative positioning strategy, and solving the double-difference observation equation by using a preset extended Kalman filtering strategy to obtain a floating-point solution of the ambiguity of the double-difference observation equation; searching and fixing the floating-point solution of the ambiguity to obtain a fixed solution of the ambiguity, and performing baseline solution on the fixed solution of the ambiguity to generate a baseline vector corresponding to the fixed solution of the ambiguity; determining the relative position information between the target rover and the virtual reference station based on the baseline vector.

[0010] Optionally, in an embodiment of the present application, the observation value of the virtual reference station is:

[0011]

[0012] Wherein, and represent the satellite signal transmission and reception times corresponding to the target satellite; successively represent the virtual reference station, the target satellite number, and the frequency; and represent the initial time and the integer ambiguity; and respectively represent the virtual pseudorange and the carrier phase observation value; and are respectively the satellite orbit and clock error corrections; and are respectively the tropospheric slant delay and the ionospheric slant delay; and are respectively the satellite pseudorange code bias and the phase bias; is the wavelength corresponding to the observation value of the th frequency point; represents the ratio of the ionospheric slant delay on the th frequency point observation value to the ionospheric slant delay on the first frequency point.

[0013] In the second aspect of the embodiments of the present application, a network RTK device for generating a virtual reference station based on PPP SSR corrections is provided, including: a correction module, configured to calculate the approximate coordinates of the target rover station, and use the approximate coordinates of the rover station and the PPP SSR information of multiple target satellites through the target server to correct the observation value errors of each target satellite among the multiple target satellites, so as to generate the position coordinates and observation values of the virtual reference station; an encoding module, configured to encode the position coordinates and the observation values based on a preset RTCM protocol, so that the target server encodes the position coordinates and the observation values to obtain OSR information corresponding to the position coordinates and the observation values, and broadcasts the OSR information to the target rover station; an acquisition module, configured to obtain the relative position information between the target rover station and the virtual reference station based on the OSR information and a preset double-difference relative positioning strategy, and determine the position coordinates of the target rover station according to the relative position information.

[0014] Optionally, in an embodiment of the present application, the correction module includes: a construction unit, configured to receive the observation values and broadcast ephemeris of the multiple target satellites through the target rover station, and construct an observation equation corresponding to the target rover station according to the observation values and broadcast ephemeris of the multiple target satellites; a calculation unit, configured to calculate the approximate coordinates of the target rover station based on a preset SPP positioning strategy, and correct the satellite orbit error, satellite clock error, and ionospheric slant delay error of the target satellite through the target server according to the observation equation, the approximate coordinates of the rover station, and the PPP SSR information, so as to obtain the position coordinates and observation values of the virtual reference station.

[0015] Optionally, in an embodiment of the present application, the acquisition module includes: a solution unit, configured to construct a double-difference observation equation according to the OSR information and the double-difference relative positioning strategy, and solve the double-difference observation equation by using a preset extended Kalman filtering strategy to obtain a floating-point solution of the ambiguity of the double-difference observation equation; a search and fixation unit, configured to search and fix the floating-point solution of the ambiguity to obtain a fixed solution of the ambiguity, and perform baseline solution on the fixed solution of the ambiguity to generate a baseline vector corresponding to the fixed solution of the ambiguity; a determination unit, configured to determine the relative position information between the target rover station and the virtual reference station based on the baseline vector.

[0016] Optionally, in an embodiment of the present application, the observation value of the virtual reference station is:

[0017]

[0018] Wherein, and represent the satellite signal transmission and reception times corresponding to the target satellite; successively represent the virtual reference station, the target satellite number, and the frequency; and represent the initial time and the integer ambiguity; and respectively represent the virtual pseudorange and the carrier phase observation value; and are respectively the satellite orbit and the clock error correction; and are respectively the tropospheric slant delay and the ionospheric slant delay; and are respectively the satellite pseudorange code bias and the phase bias; is the wavelength corresponding to the observation value of the th frequency point; represents the ratio of the ionospheric slant delay on the th frequency point observation value to the ionospheric slant delay on the first frequency point.

[0019] An embodiment of the third aspect of the present application provides an electronic device, including: a memory, a processor, and a computer program stored on the memory and executable on the processor, where the processor executes the program to implement the network RTK method for generating a virtual reference station based on the PPP SSR correction as described in the above embodiment.

[0020] An embodiment of the fourth aspect of the present application provides a computer-readable storage medium, where the computer-readable storage medium stores a computer program, and when the program is executed by a processor, it implements the network RTK method for generating a virtual reference station based on the PPP SSR correction as described above.

[0021] An embodiment of the fifth aspect of the present application provides a computer program product, including a computer program, where the computer program is executed to implement the network RTK method for generating a virtual reference station based on the PPP SSR correction as described above.

[0022] Therefore, the embodiments of the present application have the following beneficial effects:

[0023] Embodiments of the present application can calculate the approximate coordinates of the target rover station, and use the approximate coordinates of the rover station and the PPP SSR information of multiple target satellites by the target server to correct the observation value errors of each target satellite among the multiple target satellites, so as to generate the position coordinates and observation values of the virtual reference station; based on the preset RTCM protocol, enable the target server to encode the position coordinates and observation values, obtain the OSR information corresponding to the position coordinates and observation values, and broadcast the OSR information to the target rover station; based on the OSR information and the preset double-difference relative positioning strategy, enable the target rover station to obtain the relative position information between the target rover station and the virtual reference station, and determine the position coordinates of the target rover station according to the relative position information. By integrating the advantages of PPP SSR and virtual reference stations, the present application is fully compatible with existing receivers, and can effectively achieve high-precision and high-reliability navigation and positioning services. Thus, the problems of slow convergence speed, limited coverage, and poor receiver compatibility in existing navigation and positioning technologies are solved.

[0024] Additional aspects and advantages of the present application will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the following description of the embodiments in conjunction with the drawings, where:

[0026] Figure 1 is a flowchart of a network RTK (Real Time Kinematic) method for generating a virtual reference station based on PPP SSR corrections according to an embodiment of the present application;

[0027] Figure 2 is a schematic diagram of the logical architecture of a network RTK method for generating a virtual reference station based on PPP SSR corrections provided by an embodiment of the present application;

[0028] Figure 3 is an example diagram of a network RTK device for generating a virtual reference station based on PPP SSR corrections according to an embodiment of the present application;

[0029] Figure 4 is a schematic diagram of the structure of an electronic device provided by an embodiment of the present application.

[0030] Among them, 10 - network RTK device for generating a virtual reference station based on PPP SSR corrections; 100 - correction module, 200 - encoding module, 300 - acquisition module; 401 - memory, 402 - processor, 403 - communication interface. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0031] Embodiments of the present application will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the accompanying drawings are exemplary and are intended to explain the present application and should not be construed as a limitation of the present application.

[0032] The network RTK method for generating a virtual reference station based on PPP SSR corrections of the embodiments of the present application will be described below with reference to the accompanying drawings. In view of the problems mentioned in the above background art, the present application provides a network RTK method for generating a virtual reference station based on PPP SSR corrections. In this method, the approximate coordinates of the target rover are calculated, and the target server corrects the observation value errors of each of the multiple target satellites by using the approximate coordinates of the rover and the PPP SSR information of the multiple target satellites, so as to generate the position coordinates and observation values of the virtual reference station; based on the preset RTCM protocol, the target server encodes the position coordinates and observation values to obtain the OSR information corresponding to the position coordinates and observation values, and broadcasts the OSR information to the target rover; based on the OSR information and the preset double-difference relative positioning strategy, the target rover obtains the relative position information between the target rover and the virtual reference station, and determines the position coordinates of the target rover according to the relative position information. By integrating the advantages of PPP SSR and virtual reference stations, the present application is fully compatible with existing receivers and can effectively provide high-precision and high-reliability navigation and positioning services. Thus, the problems of slow convergence speed, limited coverage, and poor receiver compatibility in existing navigation and positioning technologies are solved.

[0033] Specifically, Figure 1 FIG. is a flowchart of a network RTK method for generating a virtual reference station based on PPP SSR corrections provided by an embodiment of the present application.

[0034] As Figure 1 shown, the network RTK method for generating a virtual reference station based on PPP SSR corrections includes the following steps:

[0035] In step S101, the approximate coordinates of the target rover are calculated, and the target server corrects the observation value errors of each of the multiple target satellites by using the approximate coordinates of the rover and the PPP SSR information of the multiple target satellites, so as to generate the position coordinates and observation values of the virtual reference station.

[0036] In the embodiments of the present application, firstly, the rover (i.e., the target rover) can obtain the approximate coordinates of the rover through SPP (Single Point Positioning) and upload them to the server (i.e., the target server); secondly, according to the approximate position coordinates of the rover, the embodiments of the present application can enable the server to simulate and generate a virtual reference station, and use PPP SSR to correct the errors of the observation values of the target satellites to generate the position coordinates and observation values (virtual observation values) of the virtual reference station, and generate and broadcast them to the rover, such as Figure 2 shown; after that, the embodiments of the present application can encode the position coordinates and observation values of the virtual reference station into corresponding OSR information according to the RTCM protocol and broadcast them to the rover.

[0037] Optionally, in an embodiment of the present application, calculating the approximate coordinates of the target rover, and using the approximate coordinates of the rover and the PPP SSR information of multiple target satellites to correct the observation value errors of each target satellite among the multiple target satellites to generate the position coordinates and observation values of the virtual reference station, includes: receiving the observation values and broadcast ephemeris of multiple target satellites through the target rover, and constructing an observation equation corresponding to the target rover according to the observation values and broadcast ephemeris of the multiple target satellites; based on a preset SPP positioning strategy, calculating the approximate coordinates of the target rover, and using the target server to correct the satellite orbit error, satellite clock error, and ionospheric slant delay error of the target satellite according to the observation equation, approximate coordinates of the rover, and PPP SSR information to obtain the position coordinates and observation values of the virtual reference station.

[0038] Specifically, the embodiments of the present application can first pass the rover at time to receive Beidou satellite observation values and broadcast ephemeris to obtain the observation equation of the pseudorange observation value, as shown in the following formula;

[0039]

[0040] where represents the geometric distance between the satellite and the rover receiver, and are the receiver clock error and satellite clock error respectively, and represent the ionospheric delay and tropospheric delay errors respectively, represents multipath and noise, c represents the speed of light.

[0041] Secondly, the embodiments of the present application can obtain the approximate position coordinates of the rover (i.e., the approximate coordinates of the rover) through SPP positioning and upload them to the server.

[0042] Again, in the embodiments of the present application, the server can generate virtual reference station observations based on the approximate position coordinates of the rover station and using PPP SSR error correction information.

[0043] Optionally, in an embodiment of the present application, the observations of the virtual reference station are:

[0044]

[0045] Wherein, and represent the satellite signal transmission and reception times corresponding to the target satellite; successively represent the virtual reference station, the target satellite number, and the frequency; and represent the initial time and the integer ambiguity; and respectively represent the virtual pseudorange and the carrier phase observation; and are respectively the satellite orbit and clock error corrections; and are respectively the tropospheric slant delay and the ionospheric slant delay; and are respectively the satellite pseudorange code bias and the phase bias; is the wavelength corresponding to the frequency point observation; represents the ratio of the ionospheric slant delay at the frequency point observation to the ionospheric slant delay at the first frequency point.

[0046] In the embodiments of the present application, the observations of the virtual reference station are shown as the following formula:

[0047]

[0048] Wherein, and represent the satellite signal transmission and reception times, successively represent the virtual reference station, the satellite number, and the frequency, and represent the initial time and its integer ambiguity; and respectively represent the virtual pseudorange and the carrier phase observation; and are respectively the satellite orbit and clock error corrections; and are respectively the tropospheric slant delay and the ionospheric slant delay; and are respectively the satellite pseudorange code bias and the phase bias, which can be directly obtained from SSR; is the Wavelength corresponding to the frequency point observation value Indicates the Ratio of the ionospheric slant delay at the frequency point observation value to the ionospheric slant delay at the first frequency point

[0049] It should be noted that among the observation values of the above virtual reference station Indicates the satellite - ground distance, as shown in the following formula:

[0050]

[0051] Among them, is Satellite orbital coordinates at time, which are obtained by calculating from broadcast ephemeris; Indicates the position coordinates of the virtual reference station; Is the earth tide correction, including solid tide, ocean tide, pole tide, etc.

[0052] Meanwhile, in the embodiments of the present application, Can be calculated through PPP SSR information, as shown in the following formula:

[0053]

[0054] Among them, Indicates Satellite orbital coordinates calculated by SSR correction at time

[0055] Similarly, Can be calculated through PPP SSR information, as shown in the following formula:

[0056]

[0057] Among them, Indicates Satellite clock bias correction value at time; Indicates polynomial coefficients; Indicates the reference time of the clock bias correction.

[0058] In the actual execution process, the tropospheric slant delay of the virtual reference station can first obtain the zenith dry delay and wet delay through grid interpolation, as shown in the following formula:

[0059]

[0060] Among them, and Respectively indicate Zenith dry delay and wet delay at time; n Indicates the number of grid points; Indicates the k Weight ratio of the and respectively represent the k dry delay and wet delay of the grid point at the

[0061] Therefore, the tropospheric slant delay of the virtual reference station can be obtained by calculating the projected zenith delay, as shown in the following formula:

[0062]

[0063] where represents the tropospheric slant delay of the virtual reference station at the represents the satellite elevation angle; and respectively represent the dry delay and wet delay projection functions.

[0064] In addition, in order to obtain the ionospheric slant delay of the virtual reference station, first, the slant delay of each grid point needs to be calculated, as shown in the following formula:

[0065]

[0066] where represents the k ionospheric slant delay of the grid point at the represents the total amount of tilted electrons of the grid point at the k and the f represents the frequency of the carrier phase observation value.

[0067] After that, the embodiments of the present application can obtain the ionospheric slant delay of the virtual reference station by interpolating the slant delay of the grid points, as shown in the following formula:

[0068]

[0069] where represents the ionospheric slant delay of the virtual reference station at the n represents the number of grid points; represents the k weight ratio of the grid point at the

[0070] Therefore, the embodiments of the present application enable the server to correct errors such as satellite orbit and clock bias, tropospheric and ionospheric delays, etc., so as to obtain the observation values of the virtual reference station.

[0071] After that, the embodiments of the present application can, according to the RTCM protocol, enable the server to encode the position coordinates and observation values of the virtual reference station into OSR information and broadcast the OSR information to the rover station.

[0072] Thus, in the process of generating a virtual reference station by using PPP SSR corrections for network RTK positioning in the embodiments of the present application, no additional physical reference station is required, thereby providing high-precision navigation and positioning services for global users.

[0073] In step S102, based on the preset RTCM protocol, the target server encodes the position coordinates and observations to obtain the OSR information corresponding to the position coordinates and observations, and broadcasts the OSR information to the target rover.

[0074] In step S103, based on the OSR information and the preset double-difference relative positioning strategy, the target rover obtains the relative position information between the target rover and the virtual reference station, and determines the position coordinates of the target rover according to the relative position information.

[0075] Furthermore, in the embodiments of the present application, the rover also needs to use virtual observations to form a double-difference observation equation to solve the baseline vector, and determine the rover position coordinates according to the virtual reference station position coordinates and the baseline vector.

[0076] Thus, the embodiments of the present application can take into account the advantages of both PPP SSR and virtual reference stations, and based on the network RTK of the virtual reference station, solve high-precision and high-reliability navigation and positioning results.

[0077] Optionally, in an embodiment of the present application, based on the OSR information and the preset double-difference relative positioning strategy, enabling the target rover to obtain the relative position information between the target rover and the virtual reference station includes: constructing a double-difference observation equation according to the OSR information and the double-difference relative positioning strategy, and using the preset extended Kalman filtering strategy to solve the double-difference observation equation to obtain the float solution of the ambiguity of the double-difference observation equation; performing search and fixing on the float solution of the ambiguity to obtain the fixed solution of the ambiguity, and performing baseline solution on the fixed solution of the ambiguity to generate the baseline vector corresponding to the fixed solution of the ambiguity; determining the relative position information between the target rover and the virtual reference station based on the baseline vector.

[0078] Specifically, in the embodiments of the present application, the rover can obtain the double-difference observation equation according to the pseudorange and carrier phase observations as shown in the following formula:

[0079]

[0080] Where and represent the double-difference pseudorange observation value and the double-difference carrier phase observation value; represents the double-difference satellite-to-earth distance; , I and represent the coefficient matrix, the identity matrix, and the zero matrix respectively; and represent the wavelength of the carrier phase observation value and the double-difference ambiguity respectively; and represent the double-difference pseudorange, the carrier observation noise and error respectively; represents the baseline vector at time

[0081] Secondly, the embodiment of the present application can solve the double-difference observation equation through an extended Kalman filtering strategy to obtain a floating-point solution of the ambiguity (i.e., floating-point ambiguity), and use the LAMBDA method to search and fix the floating-point ambiguity, so as to obtain a fixed solution of the ambiguity.

[0082] Thirdly, the embodiment of the present application can use the fixed solution of the ambiguity to perform baseline solution to obtain the baseline vector, and determine the position of the rover relative to the virtual reference station (i.e., the relative position information between the target rover and the virtual reference station) according to the baseline vector result, as shown in the following formula:

[0083]

[0084] wherein, represents the baseline vector result between the rover and the virtual reference station at time represents the position coordinates of the virtual reference station at time represents the position coordinates of the rover at time

[0085] Furthermore, the embodiment of the present application can also perform corresponding tests on the network RTK method for generating virtual reference stations based on PPP SSR corrections. Table 1 shows the vehicle navigation and positioning test statistical results of the network RTK method for generating virtual reference stations based on PPP SSR corrections:

[0086] Table 1

[0087]

[0088] As can be seen from Table 1, the network RTK based on PPP SSR corrections for generating virtual reference stations has a faster convergence speed, a higher ambiguity fixing rate and positioning accuracy.

[0089] In summary, the embodiment of the present application first uses the approximate coordinates of the rover and PPP SSR information to correct the errors of various observation values, generate the virtual reference station and its observation values, and encode them into OSR information and broadcast it to the rover; the rover calculates the high-precision position through relative positioning according to the position of the virtual reference station and its observation values. Thus, the embodiment of the present application is based on PPP SSR correction information, taking into account the advantages of both PPP SSR and virtual reference stations, and has great advantages in terms of accuracy, receiver compatibility and applicability.

[0090] According to the network RTK method for generating a virtual reference station based on PPP SSR corrections proposed in the embodiments of the present application, the approximate coordinates of the rover are calculated, and the target server corrects the observation value errors of each of the multiple target satellites by using the approximate coordinates of the rover and the PPP SSR information of the multiple target satellites, so as to generate the position coordinates and observation values of the virtual reference station; based on the preset RTCM protocol, the target server encodes the position coordinates and observation values to obtain the OSR information corresponding to the position coordinates and observation values, and broadcasts the OSR information to the target rover; based on the OSR information and the preset double-difference relative positioning strategy, the target rover obtains the relative position information between the target rover and the virtual reference station, and determines the position coordinates of the target rover according to the relative position information. The present application combines the advantages of PPP SSR and virtual reference stations, so as to be fully compatible with existing receivers, and can effectively achieve high-precision and high-reliability navigation and positioning services.

[0091] Secondly, a network RTK device for generating a virtual reference station based on PPP SSR corrections proposed in the embodiments of the present application will be described with reference to the accompanying drawings.

[0092] Figure 3 It is a block diagram of a network RTK device for generating a virtual reference station based on PPP SSR corrections according to an embodiment of the present application.

[0093] As Figure 3 shown, the network RTK device 10 for generating a virtual reference station based on PPP SSR corrections includes: a correction module 100, an encoding module 200, and an acquisition module 300.

[0094] Among them, the correction module 100 is used to calculate the approximate coordinates of the target rover, and the target server corrects the observation value errors of each of the multiple target satellites by using the approximate coordinates of the rover and the PPP SSR information of the multiple target satellites, so as to generate the position coordinates and observation values of the virtual reference station.

[0095] The encoding module 200 is used to, based on the preset RTCM protocol, enable the target server to encode the position coordinates and observation values to obtain the OSR information corresponding to the position coordinates and observation values, and broadcast the OSR information to the target rover.

[0096] The acquisition module 300 is used to, based on the OSR information and the preset double-difference relative positioning strategy, enable the target rover to obtain the relative position information between the target rover and the virtual reference station, and determine the position coordinates of the target rover according to the relative position information.

[0097] Optionally, in an embodiment of the present application, the correction module 100 includes: a construction unit and a calculation unit.

[0098] The construction unit is configured to receive the observations and broadcast ephemeris of multiple target satellites through a target rover station, and construct an observation equation corresponding to the target rover station according to the observations and broadcast ephemeris of the multiple target satellites.

[0099] The calculation unit is configured to calculate the approximate coordinates of the rover station based on a preset SPP positioning strategy, and correct the satellite orbit error, satellite clock error, and ionospheric slant delay error of the target satellite through the target server according to the observation equation, the approximate coordinates of the rover station, and the PPP SSR information, so as to obtain the position coordinates and observations of the virtual reference station.

[0100] Optionally, in an embodiment of the present application, the acquisition module 300 includes: a solution unit, a search and fixation unit, and a determination unit.

[0101] The solution unit is configured to construct a double-difference observation equation according to the OSR information and the double-difference relative positioning strategy, and solve the double-difference observation equation by using a preset extended Kalman filtering strategy to obtain the float solution of the ambiguity of the double-difference observation equation.

[0102] The search and fixation unit is configured to search and fix the float solution of the ambiguity to obtain the fixed solution of the ambiguity, and perform baseline solution on the fixed solution of the ambiguity to generate a baseline vector corresponding to the fixed solution of the ambiguity.

[0103] The determination unit is configured to determine the relative position information between the target rover station and the virtual reference station based on the baseline vector.

[0104] Optionally, in an embodiment of the present application, the observations of the virtual reference station are:

[0105]

[0106] Wherein, and represent the satellite signal transmission and reception times corresponding to the target satellite; represent the virtual reference station, the target satellite number, and the frequency in sequence; and represent the initial time and the integer ambiguity; and represent the virtual pseudorange and carrier phase observations respectively; and are the satellite orbit and clock error corrections respectively; and are the tropospheric slant delay and ionospheric slant delay respectively; and They are the satellite pseudorange code deviation and the phase deviation respectively; is the wavelength corresponding to the observation value of the represents the ratio of the ionospheric slant delay on the

[0107] It should be noted that the foregoing explanation of the network RTK method embodiment for generating a virtual reference station based on PPP SSR corrections also applies to the network RTK device for generating a virtual reference station based on PPP SSR corrections in this embodiment, and will not be elaborated here.

[0108] According to the network RTK device for generating a virtual reference station based on PPP SSR corrections proposed in the embodiments of the present application, it includes a correction module 100, configured to calculate the approximate coordinates of the target rover, and use the approximate coordinates of the rover and the PPP SSR information of multiple target satellites through the target server to correct the observation value errors of each target satellite among the multiple target satellites, so as to generate the position coordinates and observation values of the virtual reference station; an encoding module 200, configured to encode the position coordinates and observation values based on a preset RTCM protocol through the target server, obtain the OSR information corresponding to the position coordinates and observation values, and broadcast the OSR information to the target rover; an acquisition module 300, configured to enable the target rover to obtain the relative position information between the target rover and the virtual reference station based on the OSR information and a preset double-difference relative positioning strategy, and determine the position coordinates of the target rover according to the relative position information. The present application combines the advantages of PPP SSR and virtual reference stations, thus being fully compatible with existing receivers and effectively realizing high-precision and high-reliability navigation and positioning services.

[0109] Figure 4 It is a schematic structural diagram of an electronic device provided in the embodiments of the present application. The electronic device may include:

[0110] a memory 401, a processor 402, and a computer program stored on the memory 401 and executable on the processor 402.

[0111] When the processor 402 executes the program, it implements the network RTK method for generating a virtual reference station based on PPP SSR corrections provided in the above embodiments.

[0112] Further, the electronic device further includes:

[0113] a communication interface 403, configured for communication between the memory 401 and the processor 402.

[0114] The memory 401 is used to store a computer program executable on the processor 402.

[0115] The memory 401 may include high-speed RAM memory and may also include non-volatile memory, such as at least one magnetic disk memory.

[0116] If the memory 401, the processor 402, and the communication interface 403 are implemented independently, the communication interface 403, the memory 401, and the processor 402 can be interconnected through a bus and communicate with each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, an Extended Industry Standard Architecture (EISA) bus, or the like. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 4 only a thick line is used to represent it in the figure, but it does not mean that there is only one bus or one type of bus.

[0117] Optionally, in a specific implementation, if the memory 401, the processor 402, and the communication interface 403 are integrated on a single chip, the memory 401, the processor 402, and the communication interface 403 can communicate with each other through an internal interface.

[0118] The processor 402 may be a Central Processing Unit (CPU), or an Application Specific Integrated Circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application.

[0119] The embodiments of the present application also provide a computer-readable storage medium, on which a computer program is stored, and when the program is executed by a processor, the above network RTK method for generating a virtual reference station based on PPP SSR corrections is implemented.

[0120] The embodiments of the present application also provide a computer program product, including a computer program, and when the computer program is executed, it is used to implement the above network RTK method for generating a virtual reference station based on PPP SSR corrections.

[0121] In the description of this specification, the descriptions referring to terms such as "one embodiment", "some embodiments", "examples", "specific examples", or "some examples", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of this application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or N embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0122] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of this application, the meaning of "N" is at least two, such as two, three, etc., unless otherwise specifically defined.

[0123] Any process or method description shown in a flowchart or described in other ways herein can be understood as representing a module, segment, or part of code including one or N executable instructions for implementing a customized logical function or process, and the scope of the preferred embodiments of this application includes additional implementations, where the functions can be executed in a manner that is not in the order shown or discussed, including in a substantially simultaneous manner according to the functions involved or in a reverse order, which should be understood by those skilled in the art to which the embodiments of this application belong.

[0124] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a definite sequence list of executable instructions for implementing logical functions, and can be specifically implemented in any computer-readable medium for use by an instruction execution system, apparatus, or device (such as a computer-based system, a system including a processor, or other systems that can fetch and execute instructions from the instruction execution system, apparatus, or device), or used in combination with these instruction execution systems, apparatus, or devices. For the purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device. More specific examples (non-exhaustive list) of computer-readable media include the following: an electrical connection part (electronic device) having one or N wirings, a portable computer diskette (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Additionally, the computer-readable medium can even be paper or other suitable media on which the program can be printed, because the program can be obtained electronically by optically scanning the paper or other media, followed by editing, interpretation, or otherwise processing as appropriate, and then stored in a computer memory.

[0125] It should be understood that various parts of the present application can be implemented by hardware, software, firmware, or a combination thereof. In the above embodiments, the N steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. If implemented in hardware, as in another embodiment, any one or a combination of the following techniques well known in the art can be used: discrete logic circuits having logic gate circuits for implementing logical functions on data signals, application specific integrated circuits having appropriate combinational logic gate circuits, programmable gate arrays (PGA), field programmable gate arrays (FPGA), etc.

[0126] Those of ordinary skill in the art of this technology can understand that all or part of the steps carried by the method of the above embodiments can be completed by instructing relevant hardware through a program, and the program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiments.

[0127] In addition, each functional unit in various embodiments of the present application may be integrated into a processing module, or each unit may exist physically alone, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. When the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0128] The above-mentioned storage medium may be a read-only memory, a magnetic disk, an optical disc, etc. Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present application. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present application.

Claims

1. A network RTK method for generating a virtual reference station based on PPP SSR corrections, characterized in that, Including the following steps: Calculating the rough coordinates of the target rover station, and using the rough coordinates of the rover station and the PPP SSR information of multiple target satellites by the target server to correct the observation value errors of each target satellite among the multiple target satellites, so as to generate the position coordinates and observation values of the virtual reference station; Based on the preset RTCM protocol, enabling the target server to encode the position coordinates and the observation values to obtain the OSR information corresponding to the position coordinates and the observation values, and broadcasting the OSR information to the target rover station; Based on the OSR information and the preset double-difference relative positioning strategy, enabling the target rover station to obtain the relative position information between the target rover station and the virtual reference station, and determining the position coordinates of the target rover station according to the relative position information.

2. The network RTK method for generating a virtual reference station based on PPP SSR correction according to claim 1, wherein The calculating the rough coordinates of the target rover station, and using the rough coordinates of the rover station and the PPP SSR information of multiple target satellites by the target server to correct the observation value errors of each target satellite among the multiple target satellites, so as to generate the position coordinates and observation values of the virtual reference station, includes: Receiving the observation values and broadcast ephemeris of the multiple target satellites by the target rover station, and constructing an observation equation corresponding to the target rover station according to the observation values and broadcast ephemeris of the multiple target satellites; Based on the preset SPP positioning strategy, calculating the rough coordinates of the target rover station, and correcting the satellite orbit error, satellite clock error and ionospheric slant delay error of the target satellite by the target server according to the observation equation, the rough coordinates of the rover station and the PPP SSR information, so as to obtain the position coordinates and observation values of the virtual reference station.

3. The network RTK method for generating a virtual reference station based on PPP SSR correction according to claim 1, characterized in that, The based on the OSR information and the preset double-difference relative positioning strategy, enabling the target rover station to obtain the relative position information between the target rover station and the virtual reference station, includes: Constructing a double-difference observation equation according to the OSR information and the double-difference relative positioning strategy, and solving the double-difference observation equation by using the preset extended Kalman filtering strategy to obtain the floating-point solution of the ambiguity of the double-difference observation equation; Searching and fixing the floating-point solution of the ambiguity to obtain the fixed solution of the ambiguity, and performing baseline solution on the fixed solution of the ambiguity to generate a baseline vector corresponding to the fixed solution of the ambiguity; Based on the baseline vector, determining the relative position information between the target rover station and the virtual reference station.

4. The network RTK method for generating a virtual reference station based on PPP SSR correction according to claim 1, wherein The observation value of the virtual reference station is: Wherein, and represent the satellite signal transmission and reception times corresponding to the target satellite; successively represent the virtual reference station, the target satellite number and frequency; and represent the initial time and the integer ambiguity; and respectively represent the virtual pseudorange and the carrier phase observation value; and are respectively the satellite orbit and the clock error correction; and are respectively the tropospheric slant delay and the ionospheric slant delay; and are respectively the satellite pseudorange code bias and the phase bias; is the wavelength corresponding to the frequency point observation value; represents the ratio of the ionospheric slant delay at the frequency point observation value to the ionospheric slant delay at the first frequency point.

5. A network RTK device for generating a virtual reference station based on PPP SSR corrections, characterized in that, Including: A correction module, configured to calculate the rough coordinates of the target rover station, and use the rough coordinates of the rover station and the PPP SSR information of multiple target satellites by the target server to correct the observation value errors of each target satellite among the multiple target satellites, so as to generate the position coordinates and observation values of the virtual reference station; An encoding module, configured to encode the position coordinates and the observation values based on the preset RTCM protocol, so that the target server encodes the position coordinates and the observation values to obtain the OSR information corresponding to the position coordinates and the observation values, and broadcasts the OSR information to the target rover station; An acquisition module, configured to enable the target rover to acquire the relative position information between the target rover and the virtual reference station based on the OSR information and a preset double-difference relative positioning strategy, and determine the position coordinates of the target rover according to the relative position information.

6. The network RTK device for generating a virtual reference station based on PPP SSR correction according to claim 5, characterized in that The correction module includes: A construction unit, configured to receive the observations and broadcast ephemerides of the multiple target satellites through the target rover, and construct an observation equation corresponding to the target rover according to the observations and broadcast ephemerides of the multiple target satellites; A calculation unit, configured to calculate the approximate coordinates of the rover of the target rover based on a preset SPP positioning strategy, and correct the satellite orbit error, satellite clock error, and ionospheric slant delay error of the target satellite by the target server according to the observation equation, the approximate coordinates of the rover, and the PPP SSR information, so as to obtain the position coordinates and observations of the virtual reference station.

7. The network RTK device for generating a virtual reference station based on PPP SSR correction according to claim 5, wherein The acquisition module includes: A solution unit, configured to construct a double-difference observation equation according to the OSR information and the double-difference relative positioning strategy, and solve the double-difference observation equation by using a preset extended Kalman filtering strategy to obtain a floating-point solution of the ambiguity of the double-difference observation equation; A search and fixation unit, configured to search and fix the floating-point solution of the ambiguity to obtain a fixed solution of the ambiguity, and perform baseline solution on the fixed solution of the ambiguity to generate a baseline vector corresponding to the fixed solution of the ambiguity; A determination unit, configured to determine the relative position information between the target rover and the virtual reference station based on the baseline vector.

8. An electronic device, characterized in that, Includes: A memory, a processor, and a computer program stored on the memory and executable on the processor, where the processor executes the program to implement the network RTK method for generating a virtual reference station based on PPP SSR corrections as described in any one of claims 1-4.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, The program is executed by the processor to be used to implement the network RTK method for generating a virtual reference station based on PPP SSR corrections as described in any one of claims 1-4.

10. A computer program product, comprising a computer program, characterized in that, The computer program is executed to be used to implement the network RTK method for generating a virtual reference station based on PPP SSR corrections as described in any one of claims 1-4.

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