Network RTK method for generating virtual reference station based on PPP SSR correction

Abstract

The invention relates to the technical field of global satellite navigation systems, in particular to a network RTK (Real Time Kinematic) method for generating a virtual reference station based on a PPP (Point-to-Point Protocol) SSR (Simple Sequence Repeat) correction, which comprises the following steps of: calculating a moving station approximate coordinate of a target moving station; an observation value error of each target satellite is corrected through the target server by using the rough coordinate of the moving station and the PPP SSR information of the plurality of target satellites, and a position coordinate and an observation value of a virtual reference station are generated; on the basis of an RTCM protocol, the target server side 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 moving station; and based on the OSR information and a double-difference relative positioning strategy, enabling the target moving station to obtain relative position information between the target moving station and the virtual reference station so as to determine position coordinates of the target moving station. Therefore, the problems of slow convergence, limited coverage range, poor receiver compatibility and the like of the existing navigation positioning technology are solved.

Description

Technical Field

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

[0002] The Global Navigation Satellite System (GNSS) can provide high-precision distance observations and achieve 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 meters, which cannot meet the needs of intelligent transportation applications. Therefore, it is necessary to eliminate GNSS observation errors to further improve positioning accuracy, such as orbit and clock errors, hardware bias, atmospheric delay, etc.

[0003] Virtual Reference Stations (VRS) technology virtually translates the actual observation values ​​of the main reference station to the vicinity of the mobile station, virtually generates a reference station, and broadcasts the generated virtual observation values ​​or error correction numbers to the mobile station as high-precision differential signals, forming an ultra-short baseline to obtain high-precision positioning results. VRS technology has a wide coverage, high positioning accuracy, and strong reliability, and has become a hot topic in precision positioning research.

[0004] However, when the mobile station is beyond the coverage of the base station, differential dynamic positioning needs to re-determine a new base station. Real-time PPP (Precise Point Positioning) technology achieves high-precision positioning by receiving correction information in the state space representation (SSR) format. SSR correction information contains observation errors such as orbit, clock error, pseudorange deviation and atmospheric delay, and is broadcast free of charge to users around the world by the IGS (International GNSS Service). Currently, commercial receivers can receive RTCM (Radio Technical Commission for Maritime) OSR (Observation Space Representation) information, but most do not receive RTCM SSR. Although the next generation of receivers are starting to use RTCMSSR, existing receivers can only receive RTCM OSR.

[0005] In summary, the existing navigation and positioning technology has slow convergence speed, limited coverage, and poor receiver compatibility, which need to be urgently addressed. Summary of the invention

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

[0007] The first aspect of the present application provides a network RTK method for generating a virtual reference station based on PPP SSR correction numbers, comprising the following steps: calculating the approximate coordinates of a target mobile station, and correcting the observation value error of each of the multiple target satellites through a target server using the approximate coordinates of the mobile station and the PPP SSR information of multiple target satellites to generate the position coordinates and observation values ​​of the virtual reference station; based on a preset RTCM protocol, the target server encodes the position coordinates and the observation values, obtains OSR information corresponding to the position coordinates and the observation values, and broadcasts the OSR information to the target mobile station; based on the OSR information and a preset double-difference relative positioning strategy, the target mobile station obtains the relative position information between the target mobile station and the virtual reference station, and determines the position coordinates of the target mobile station according to the relative position information.

[0008] Optionally, in one embodiment of the present application, the approximate coordinates of the target mobile station are calculated, and the observation value error of each target satellite in the multiple target satellites is corrected through the target server using the approximate coordinates of the mobile station and the PPP SSR information of the multiple target satellites to generate the position coordinates and observation values ​​of the virtual reference station, including: receiving the observation values ​​and broadcast ephemeris of the multiple target satellites through the target mobile station, and constructing the observation equation corresponding to the target mobile station according to the observation values ​​and broadcast ephemeris of the multiple target satellites; based on the preset SPP positioning strategy, the approximate coordinates of the target mobile station are calculated, and the satellite orbit error, satellite clock error and ionospheric slant delay error of the target satellite are corrected through the target server according to the observation equation, the approximate coordinates of the mobile station and the PPP SSR information to obtain the position coordinates and observation values ​​of the virtual reference station.

[0009] Optionally, in one embodiment of the present application, the OSR information and the preset double-difference relative positioning strategy are used to enable the target mobile station to obtain the relative position information between the target mobile station and the virtual reference station, including: 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 using a preset extended Kalman filter strategy to obtain an ambiguity floating-point solution of the double-difference observation equation; searching and fixing the ambiguity floating-point solution to obtain an ambiguity fixed solution, and performing baseline resolution on the ambiguity fixed solution to generate a baseline vector corresponding to the ambiguity fixed solution; based on the baseline vector, determining the relative position information between the target mobile station and the virtual reference station.

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

[0011] in, and Indicates the satellite signal transmission and reception time corresponding to the target satellite; Indicate the virtual reference station, the target satellite number and frequency in sequence; and represents the initial moment and integer ambiguity; and represent virtual pseudorange and carrier phase observation values ​​respectively; and are satellite orbit and clock corrections respectively; and They are the tropospheric oblique delay and the ionospheric oblique delay respectively; and are the satellite pseudorange code bias and phase bias respectively; For the The wavelength corresponding to the frequency point observation value; Indicates The ratio of the ionospheric slant delay at the observed frequency point to the ionospheric slant delay at the first frequency point.

[0012] The second aspect of the present application provides a network RTK device for generating a virtual reference station based on PPP SSR correction numbers, including: a correction module, used to calculate the approximate coordinates of a target mobile station, and use the approximate coordinates of the mobile station and the PPP SSR information of multiple target satellites to correct the observation value error of each target satellite in the multiple target satellites through a target server to generate the position coordinates and observation values ​​of the virtual reference station; an encoding module, used to enable the target server to encode the position coordinates and the observation values ​​based on a preset RTCM protocol, obtain OSR information corresponding to the position coordinates and the observation values, and broadcast the OSR information to the target mobile station; an acquisition module, used to enable the target mobile station to obtain the relative position information between the target mobile 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 mobile station according to the relative position information.

[0013] Optionally, in one embodiment of the present application, the correction module includes: a construction unit, used to receive the observation values ​​and broadcast ephemeris of the multiple target satellites through the target mobile station, and construct the observation equation corresponding to the target mobile station according to the observation values ​​and broadcast ephemeris of the multiple target satellites; a calculation unit, used to calculate the approximate coordinates of the target mobile 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 according to the observation equation, the approximate coordinates of the mobile station and the PPP SSR information through the target server to obtain the position coordinates and observation values ​​of the virtual reference station.

[0014] Optionally, in one embodiment of the present application, the acquisition module includes: a solving unit, used to construct a double difference observation equation according to the OSR information and the double difference relative positioning strategy, and use a preset extended Kalman filter strategy to solve the double difference observation equation to obtain the ambiguity floating-point solution of the double difference observation equation; a search and fixation unit, used to search and fix the ambiguity floating-point solution to obtain an ambiguity fixed solution, and perform baseline solution on the ambiguity fixed solution to generate a baseline vector corresponding to the ambiguity fixed solution; a determination unit, used to determine the relative position information between the target mobile station and the virtual reference station based on the baseline vector.

[0015] Optionally, in one embodiment of the present application, the observation value of the virtual reference station is:

[0016] in, and Indicates the satellite signal transmission and reception time corresponding to the target satellite; Indicate the virtual reference station, the target satellite number and frequency in sequence; and represents the initial moment and integer ambiguity; and represent virtual pseudorange and carrier phase observation values ​​respectively; and are satellite orbit and clock corrections respectively; and They are the tropospheric oblique delay and the ionospheric oblique delay respectively; and are the satellite pseudorange code bias and phase bias respectively; For the The wavelength corresponding to the frequency point observation value; Indicates The ratio of the ionospheric slant delay at the observed frequency point to the ionospheric slant delay at the first frequency point.

[0017] A third aspect of the present application provides an electronic device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement a network RTK method for generating a virtual reference station based on PPP SSR correction numbers as described in the above embodiment.

[0018] The fourth aspect embodiment of the present application provides a computer-readable storage medium, which stores a computer program. When the program is executed by a processor, it implements the above-mentioned network RTK method for generating a virtual reference station based on PPP SSR correction numbers.

[0019] The fifth aspect of the present application provides a computer program product, including a computer program, which is executed to implement the above-mentioned network RTK method for generating a virtual reference station based on PPP SSR correction numbers.

[0020] Therefore, the embodiments of the present application have the following beneficial effects: The embodiments of the present application can calculate the approximate coordinates of the target mobile station, and use the approximate coordinates of the mobile station and the PPP SSR information of the multiple target satellites to correct the observation value errors of each target satellite in the multiple target satellites through the target service end to generate the position coordinates and observation values ​​of the virtual reference station; based on the preset RTCM protocol, the target service end encodes the position coordinates and observation values, obtains the OSR information corresponding to the position coordinates and observation values, and broadcasts the OSR information to the target mobile station; based on the OSR information and the preset double-difference relative positioning strategy, the target mobile station obtains the relative position information between the target mobile station and the virtual reference station, and determines the position coordinates of the target mobile station according to the relative position information. The present application integrates the advantages of PPP SSR and virtual reference stations, so as to be fully compatible with existing receivers and can effectively realize high-precision and high-reliability navigation and positioning services. As a result, the problems of slow convergence speed, limited coverage, and poor receiver compatibility of existing navigation and positioning technologies are solved.

[0021] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which: Figure 1 A flowchart of a network RTK (Real Time Kinematic) method for generating a virtual reference station based on PPP SSR correction numbers according to an embodiment of the present application; Figure 2 A schematic diagram of the logical architecture of a network RTK method for generating a virtual reference station based on PPP SSR correction numbers provided in one embodiment of the present application; Figure 3 This is an example diagram of a network RTK device that generates a virtual reference station based on PPP SSR correction numbers according to an embodiment of the present application; Figure 4 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application.

[0023] Among them, 10 is a network RTK device for generating a virtual reference station based on PPP SSR correction numbers; 100 is a correction module, 200 is an encoding module, 300 is an acquisition module; 401 is a memory, 402 is a processor, and 403 is a communication interface. DETAILED DESCRIPTION

[0024] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0025] The following describes the network RTK method for generating a virtual reference station based on PPP SSR correction numbers in an embodiment of the present application with reference to the accompanying drawings. In response to the problems mentioned in the above background technology, the present application provides a network RTK method for generating a virtual reference station based on PPP SSR correction numbers. In this method, the approximate coordinates of the mobile station of the target mobile station are calculated, and the target service end uses the approximate coordinates of the mobile station and the PPP SSR information of multiple target satellites to correct the observation value error of each target satellite in multiple target satellites to generate the position coordinates and observation values ​​of the virtual reference station; based on the preset RTCM protocol, the target service end encodes the position coordinates and observation values, obtains the OSR information corresponding to the position coordinates and observation values, and broadcasts the OSR information to the target mobile station; based on the OSR information and the preset double-difference relative positioning strategy, the target mobile station obtains the relative position information between the target mobile station and the virtual reference station, and determines the position coordinates of the target mobile 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 realize high-precision and high-reliability navigation and positioning services. This solves the problems of slow convergence speed, limited coverage, and poor receiver compatibility of existing navigation and positioning technologies.

[0026] Specifically, Figure 1 A flowchart of a network RTK method for generating a virtual reference station based on PPP SSR correction numbers provided in an embodiment of the present application.

[0027] like Figure 1 As shown, the network RTK method for generating a virtual reference station based on PPP SSR corrections includes the following steps: In step S101, the rough coordinates of the target mobile station are calculated, and the observation value error of each target satellite in the multiple target satellites is corrected by the target service end using the rough coordinates of the mobile station and the PPP SSR information of the multiple target satellites to generate the position coordinates and observation values ​​of the virtual reference station. The embodiment of the present application can firstly use the mobile station (i.e., the target mobile station) to obtain the approximate coordinates of the mobile station through SPP (Single Point Positioning) and upload it to the server (i.e., the target server); secondly, the embodiment of the present application can enable the server to simulate and generate a virtual reference station based on the approximate position coordinates of the mobile station, and use PPP SSR to correct the errors of various observation values ​​of the target satellite to generate the position coordinates of the virtual reference station and the observation values ​​of the virtual reference station (virtual observation values), which are generated and broadcasted to the mobile station, such as Figure 2 As shown; thereafter, the embodiment of the present application can encode the virtual reference station position coordinates and observation values ​​into corresponding OSR information according to the RTCM protocol, and broadcast it to the mobile station.

[0028] Optionally, in one embodiment of the present application, the approximate coordinates of the target mobile station are calculated, and the observation value error of each target satellite in the multiple target satellites is corrected by the target server using the approximate coordinates of the mobile station and the PPP SSR information of the multiple target satellites to generate the position coordinates and observation values ​​of the virtual reference station, including: receiving the observation values ​​and broadcast ephemeris of the multiple target satellites through the target mobile station, and constructing the observation equation corresponding to the target mobile station according to the observation values ​​and broadcast ephemeris of the multiple target satellites; based on the preset SPP positioning strategy, the approximate coordinates of the target mobile station are calculated, and the satellite orbit error, satellite clock error and ionospheric slant delay error of the target satellite are corrected by the target server according to the observation equation, the approximate coordinates of the mobile station and the PPP SSR information to obtain the position coordinates and observation values ​​of the virtual reference station.

[0029] Specifically, the embodiments of the present application can first be performed by a mobile station Receive Beidou satellite observations and broadcast ephemeris at all times to obtain the observation equation of pseudorange observations, as shown below;

[0030] in, represents the geometric distance between the satellite and the mobile station receiver, and are the receiver clock error and the satellite clock error, respectively. and denote the ionospheric delay and tropospheric delay errors respectively, represents multipath and noise, c Represents the speed of light.

[0031] Secondly, the embodiment of the present application can obtain the approximate position coordinates of the mobile station (i.e., the approximate coordinates of the mobile station) through SPP positioning. and upload it to the server.

[0032] Again, the embodiments of the present application can generate virtual reference station observation values ​​by using PPP SSR error correction information based on the approximate position coordinates of the mobile station through the server.

[0033] Optionally, in one embodiment of the present application, the observation value of the virtual reference station is:

[0034] in, and Indicates the time of transmitting and receiving satellite signals corresponding to the target satellite; It represents the virtual reference station, target satellite number and frequency in turn; and represents the initial moment and integer ambiguity; and represent virtual pseudorange and carrier phase observation values ​​respectively; and are satellite orbit and clock corrections respectively; and They are the tropospheric oblique delay and the ionospheric oblique delay respectively; and are the satellite pseudorange code bias and phase bias respectively; For the The wavelength corresponding to the frequency point observation value; Indicates The ratio of the ionospheric slant delay at the observed frequency point to the ionospheric slant delay at the first frequency point.

[0035] In an embodiment of the present application, the observation value of the virtual reference station is shown as follows:

[0036] in, and Indicates the time when satellite signals are transmitted and received. In turn, they represent the virtual reference station, satellite number and frequency. and represents the initial moment and its integer ambiguity; and represent virtual pseudorange and carrier phase observation values ​​respectively; and are satellite orbit and clock corrections respectively; and They are the tropospheric oblique delay and the ionospheric oblique delay respectively; and They are the satellite pseudorange code deviation and phase deviation, which can be directly obtained from SSR; For the The frequency point observation value corresponds to the wavelength; Indicates The ratio of the ionospheric slant delay at the observed frequency point to the ionospheric slant delay at the first frequency point. It should be noted that the observation values ​​of the above virtual reference stations are It represents the satellite-to-ground distance, as shown in the following formula:

[0037] in, for Satellite orbit coordinates at the moment, which are obtained by broadcast ephemeris calculation; Indicates the location coordinates of the virtual reference station; Correction for the earth's tides, including solid tides, ocean tides, polar tides, etc.

[0038] Meanwhile, in the embodiments of the present application, It can be calculated through PPP SSR information, as shown in the following formula:

[0039] in, express The satellite orbit coordinates calculated using the SSR corrections at this moment.

[0040] Likewise, It can be calculated through PPP SSR information, as shown in the following formula:

[0041] in, express Satellite clock correction value at the moment; represents polynomial coefficients; Indicates the reference time of the clock correction number.

[0042] In the actual implementation process, the tropospheric slant delay of the virtual reference station can first be obtained by grid interpolation to obtain the zenith dry delay and wet delay, as shown in the following formula:

[0043] in, and Respectively Zenith dry delay and wet delay at time; n Indicates the number of grid points; Indicates k Weight ratio of grid points; and Respectively Moment k Dry and wet delays at the grid points.

[0044] Therefore, the tropospheric slant delay of the virtual reference station can be obtained by calculating the projected zenith delay as shown below:

[0045] in, express The tropospheric slant delay of the virtual reference station at the moment; Indicates the satellite altitude angle; and represent the dry delay and wet delay projection functions respectively.

[0046] In addition, in order to obtain the ionospheric slant delay of the virtual reference station, the slant delay of each grid point must first be calculated, as shown in the following formula:

[0047] in, Indicates k Ionospheric slant delay at the grid points; express Moment k The total number of tilted electrons at the grid points; f Represents the frequency of the carrier phase observations.

[0048] Afterwards, the embodiment 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:

[0049] in, express The ionospheric slant delay of the virtual reference station at time instant; n Indicates the number of grid points; Indicates k The weight ratio of the grid points.

[0050] Therefore, the embodiment of the present application enables the server to obtain the observation value of the virtual reference station by correcting errors such as satellite orbit and clock error, tropospheric and ionospheric delays, etc.

[0051] Afterwards, the embodiment of the present application can enable the server to encode the virtual reference station position coordinates and observation values ​​into OSR information according to the RTCM protocol, and broadcast the OSR information to the mobile station.

[0052] Therefore, in the embodiment of the present application, no additional physical reference stations are required during the process of network RTK positioning by using PPP SSR correction numbers to generate virtual reference stations, thereby providing high-precision navigation and positioning services to users around the world.

[0053] In step S102, based on the preset RTCM protocol, the target server encodes the position coordinates and the observation values, obtains OSR information corresponding to the position coordinates and the observation values, and broadcasts the OSR information to the target mobile station.

[0054] In step S103, based on the OSR information and the preset double-difference relative positioning strategy, the target mobile station obtains the relative position information between the target mobile station and the virtual reference station, and determines the position coordinates of the target mobile station according to the relative position information.

[0055] Furthermore, in an embodiment of the present application, the mobile station also needs to use virtual observation values ​​to form a double-difference observation equation to solve the baseline vector, and determine the mobile station position coordinates based on the virtual reference station position coordinates and the baseline vector.

[0056] Therefore, the embodiments of the present application can take into account the advantages of both PPP SSR and virtual reference stations, and use network RTK based on virtual reference stations to solve high-precision and high-reliability navigation and positioning results.

[0057] Optionally, in one embodiment of the present application, based on OSR information and a preset double-difference relative positioning strategy, the target mobile station obtains the relative position information between the target mobile station and the virtual reference station, including: 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 using a preset extended Kalman filter strategy to obtain an ambiguity floating-point solution of the double-difference observation equation; searching and fixing the ambiguity floating-point solution to obtain an ambiguity fixed solution, and performing baseline resolution on the ambiguity fixed solution to generate a baseline vector corresponding to the ambiguity fixed solution; based on the baseline vector, determining the relative position information between the target mobile station and the virtual reference station.

[0058] Specifically, in the embodiment of the present application, the mobile station can obtain the double difference observation equation according to the pseudorange and carrier phase observation values ​​as shown in the following formula:

[0059] in, and represents double-difference pseudorange observations and double-difference carrier phase observations; Indicates double differential satellite ground distance; , I and denote the coefficient matrix, identity matrix and zero matrix respectively; and denote the wavelength and double-difference ambiguity of the carrier phase observations, respectively; and denote the double-difference pseudorange and carrier observation noise and error respectively; express The baseline vector at the moment.

[0060] Secondly, the embodiments of the present application can solve the double-difference observation equation through an extended Kalman filtering strategy to obtain an ambiguity floating-point solution (i.e., floating-point ambiguity), and use the LAMBDA method to search and fix the floating-point ambiguity to obtain an ambiguity fixed solution.

[0061] Again, the embodiment of the present application can use the ambiguity fixed solution to perform baseline solution to obtain a baseline vector, and determine the position of the mobile station relative to the virtual reference station (that is, the relative position information between the target mobile station and the virtual reference station) according to the baseline vector result, as shown in the following formula:

[0062] in, express The baseline vector result between the mobile station and the virtual reference station at the moment; express The position coordinates of the virtual reference station at the moment; express The position coordinates of the mobile station at the moment.

[0063] Furthermore, the embodiment of the present application can also perform corresponding tests on the network RTK method for generating a virtual reference station based on PPP SSR correction numbers. Table 1 shows the statistical results of the vehicle navigation positioning test of the network RTK method for generating a virtual reference station based on PPP SSR correction numbers: Table 1

[0064] It can be seen from Table 1 that the network RTK based on the PPP SSR correction number to generate the virtual reference station has a faster convergence speed, higher ambiguity fixation rate and positioning accuracy.

[0065] In summary, the embodiment of the present application first uses the approximate coordinates of the mobile station and the PPP SSR information to correct the errors of various observation values, generate a virtual reference station and its observation values, and encode them into OSR information and broadcast them to the mobile station; the mobile station calculates the high-precision position through relative positioning based on the position of the virtual reference station and its observation values. Therefore, the embodiment of the present application is based on the PPPSSR correction information, taking into account the advantages of both PPP SSR and virtual reference station, and has great advantages in accuracy, receiver compatibility and applicability.

[0066] According to the network RTK method for generating a virtual reference station based on PPP SSR correction numbers proposed in the embodiment of the present application, the approximate coordinates of the mobile station of the target mobile station are calculated, and the target server uses the approximate coordinates of the mobile station and the PPP SSR information of multiple target satellites to correct the observation value errors of each target satellite in multiple target satellites 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, obtains the OSR information corresponding to the position coordinates and observation values, and broadcasts the OSR information to the target mobile station; based on the OSR information and the preset double-difference relative positioning strategy, the target mobile station obtains the relative position information between the target mobile station and the virtual reference station, and determines the position coordinates of the target mobile station according to the relative position information. The present application is fully compatible with existing receivers by integrating the advantages of PPP SSR and virtual reference stations, and can effectively realize high-precision and high-reliability navigation and positioning services.

[0067] Secondly, the network RTK device for generating a virtual reference station based on PPP SSR correction numbers proposed in an embodiment of the present application is described with reference to the accompanying drawings.

[0068] Figure 3 It is a block diagram of a network RTK device for generating a virtual reference station based on PPP SSR correction numbers according to an embodiment of the present application.

[0069] like Figure 3 As shown, the network RTK device 10 for generating a virtual reference station based on PPP SSR correction numbers includes: a correction module 100 , an encoding module 200 and an acquisition module 300 .

[0070] Among them, the correction module 100 is used to calculate the approximate coordinates of the target mobile station, and correct the observation value error of each target satellite in the multiple target satellites using the approximate coordinates of the mobile station and the PPP SSR information of the multiple target satellites through the target service end to generate the position coordinates and observation values ​​of the virtual reference station.

[0071] The encoding module 200 is used to enable the target server to encode the position coordinates and the observation values ​​based on the preset RTCM protocol, obtain the OSR information corresponding to the position coordinates and the observation values, and broadcast the OSR information to the target mobile station.

[0072] The acquisition module 300 is used to enable the target mobile station to acquire the relative position information between the target mobile station and the virtual reference station based on the OSR information and the preset double-difference relative positioning strategy, and determine the position coordinates of the target mobile station according to the relative position information.

[0073] Optionally, in one embodiment of the present application, the correction module 100 includes: a construction unit and a calculation unit.

[0074] The construction unit is used to receive the observation values ​​and broadcast ephemeris of multiple target satellites through the target mobile station, and construct the observation equation corresponding to the target mobile station according to the observation values ​​and broadcast ephemeris of the multiple target satellites.

[0075] The calculation unit is used to calculate the approximate coordinates of the target mobile station based on the preset SPP positioning strategy, and correct the satellite orbit error, satellite clock error and ionospheric slant delay error of the target satellite according to the observation equation, the approximate coordinates of the mobile station and the PPP SSR information through the target server to obtain the position coordinates and observation values ​​of the virtual reference station.

[0076] Optionally, in one embodiment of the present application, the acquisition module 300 includes: a solving unit, a searching and fixing unit and a determining unit.

[0077] Among them, the solving unit is used 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 using a preset extended Kalman filter strategy to obtain the ambiguity floating-point solution of the double difference observation equation.

[0078] The search and fixation unit is used to search and fix the ambiguity floating point solution to obtain the ambiguity fixed solution, and perform baseline resolution on the ambiguity fixed solution to generate a baseline vector corresponding to the ambiguity fixed solution.

[0079] The determination unit is used to determine the relative position information between the target mobile station and the virtual reference station based on the baseline vector.

[0080] Optionally, in one embodiment of the present application, the observation value of the virtual reference station is:

[0081] in, and Indicates the time of transmitting and receiving satellite signals corresponding to the target satellite; It represents the virtual reference station, target satellite number and frequency in turn; and represents the initial moment and integer ambiguity; and represent virtual pseudorange and carrier phase observation values ​​respectively; and are satellite orbit and clock corrections respectively; and They are the tropospheric oblique delay and the ionospheric oblique delay respectively; and are the satellite pseudorange code bias and phase bias respectively; For the The wavelength corresponding to the frequency point observation value; Indicates The ratio of the ionospheric slant delay at the observed frequency point to the ionospheric slant delay at the first frequency point.

[0082] It should be noted that the aforementioned explanation of the embodiment of the network RTK method for generating a virtual reference station based on PPP SSR correction numbers is also applicable to the network RTK device for generating a virtual reference station based on PPP SSR correction numbers in this embodiment, and will not be repeated here.

[0083] The network RTK device for generating a virtual reference station based on PPP SSR correction numbers according to the embodiment of the present application includes a correction module 100 for calculating the approximate coordinates of the target mobile station, and correcting the observation value errors of each target satellite in multiple target satellites through the target server using the approximate coordinates of the mobile station and the PPP SSR information of multiple target satellites to generate the position coordinates and observation values ​​of the virtual reference station; an encoding module 200 for encoding the position coordinates and observation values ​​based on the preset RTCM protocol so that the target server can obtain the OSR information corresponding to the position coordinates and observation values, and broadcast the OSR information to the target mobile station; an acquisition module 300 for enabling the target mobile station to obtain the relative position information between the target mobile station and the virtual reference station based on the OSR information and the preset double-difference relative positioning strategy, and determine the position coordinates of the target mobile station based on the relative position information. The present application is fully compatible with existing receivers by integrating the advantages of PPP SSR and virtual reference stations, and can effectively realize high-precision and high-reliability navigation and positioning services.

[0084] Figure 4 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. The electronic device may include: Memory 401 , processor 402 , and a computer program stored in the memory 401 and executable on the processor 402 .

[0085] When the processor 402 executes the program, the network RTK method for generating a virtual reference station based on PPP SSR correction numbers provided in the above embodiment is implemented.

[0086] Furthermore, the electronic device further comprises: The communication interface 403 is used for communication between the memory 401 and the processor 402 .

[0087] The memory 401 is used to store computer programs that can be executed on the processor 402 .

[0088] The memory 401 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0089] 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 connected to each other through a bus and communicate with each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component (PCI) bus or an Extended Industry Standard Architecture (EISA) bus. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 4 Only one thick line is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0090] Optionally, in a specific implementation, if the memory 401, the processor 402 and the communication interface 403 are integrated on a chip, the memory 401, the processor 402 and the communication interface 403 can communicate with each other through an internal interface.

[0091] 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.

[0092] An embodiment of the present application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the network RTK method for generating a virtual reference station based on PPP SSR correction numbers as described above.

[0093] An embodiment of the present application also provides a computer program product, including a computer program, which, when executed, is used to implement the above-mentioned network RTK method for generating a virtual reference station based on PPP SSR correction numbers.

[0094] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present 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 may be combined in any one or N embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0095] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, "N" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0096] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or N executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

[0097] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples (non-exhaustive list) of computer-readable media include the following: an electrical connection with one or N wirings (electronic device), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways as necessary and then storing it in a computer memory.

[0098] It should be understood that the various parts of the present application can be implemented by hardware, software, firmware or a combination thereof. In the above embodiment, 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 by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0099] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

[0100] In addition, each functional unit in each embodiment of the present application may be integrated into a processing module, or each unit may exist physically separately, 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. If 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.

[0101] The storage medium mentioned above may be a read-only memory, a magnetic disk or an optical disk, 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 cannot be understood as limiting the present application. A person of ordinary skill in the art may change, modify, replace and modify 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: The following steps are involved: Calculating the approximate coordinates of the target mobile station, and correcting the observation value error of each target satellite in the multiple target satellites by using the approximate coordinates of the mobile station and the PPP SSR information of the multiple target satellites through the target server to generate the position coordinates and the observation value of the virtual reference station; Based on a preset RTCM protocol, the target server encodes the position coordinates and the observation value, obtains OSR information corresponding to the position coordinates and the observation value, and broadcasts the OSR information to the target mobile station; Based on the OSR information and a preset double-difference relative positioning strategy, the target mobile station acquires relative position information between the target mobile station and the virtual reference station, and determines the position coordinates of the target mobile station according to the relative position information.

2. The network RTK method for generating a virtual reference station based on PPP SSR corrections according to claim 1, characterized in that: The calculating of the mobile station rough coordinates of the target mobile station, and correcting the observation value error of each target satellite in the multiple target satellites by using the mobile station rough coordinates and PPP SSR information of the multiple target satellites through the target server to generate the position coordinates and observation values ​​of the virtual reference station, including: Receiving the observation values ​​and broadcast ephemeris of the plurality of target satellites through the target mobile station, and constructing the observation equation corresponding to the target mobile station according to the observation values ​​and broadcast ephemeris of the plurality of target satellites; Based on the preset SPP positioning strategy, the approximate coordinates of the target mobile station are calculated, and the satellite orbit error, satellite clock error and ionospheric slant delay error of the target satellite are corrected by the target server according to the observation equation, the approximate coordinates of the mobile station and the PPP SSR information 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 corrections according to claim 1, characterized in that: The step of enabling the target mobile station to obtain relative position information between the target mobile station and the virtual reference station based on the OSR information and a preset double-difference relative positioning strategy 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 using a preset extended Kalman filter strategy to obtain an ambiguity floating-point solution of the double-difference observation equation; Searching and fixing the ambiguity floating point solution to obtain an ambiguity fixed solution, and performing baseline resolution on the ambiguity fixed solution to generate a baseline vector corresponding to the ambiguity fixed solution; Based on the baseline vector, relative position information between the target mobile station and the virtual reference station is determined.

4. The network RTK method for generating a virtual reference station based on PPP SSR corrections according to claim 1, characterized in that: The observation values ​​of the virtual reference station are: in, and Indicates the satellite signal transmission and reception time corresponding to the target satellite; Indicate the virtual reference station, the target satellite number and frequency in sequence; and represents the initial moment and integer ambiguity; and represent virtual pseudorange and carrier phase observation values ​​respectively; and are satellite orbit and clock corrections respectively; and They are the tropospheric slant delay and the ionospheric slant delay respectively; and are the satellite pseudorange code bias and phase bias respectively; For the The wavelength corresponding to the frequency point observation value; Indicates The ratio of the ionospheric slant delay at the observed frequency point 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: include: a correction module, used for calculating the rough coordinates of the mobile station of the target mobile station, and correcting the observation value error of each target satellite in the multiple target satellites by using the rough coordinates of the mobile station and the PPP SSR information of the multiple target satellites through the target service end, so as to generate the position coordinates and the observation value of the virtual reference station; An encoding module, configured to enable a target server to encode the position coordinates and the observation value based on a preset RTCM protocol, obtain OSR information corresponding to the position coordinates and the observation value, and broadcast the OSR information to the target mobile station; The acquisition module is used to enable the target mobile station to acquire the relative position information between the target mobile 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 mobile station according to the relative position information.

6. The network RTK device for generating a virtual reference station based on PPP SSR corrections according to claim 5, characterized in that: The correction module comprises: A construction unit, configured to receive the observation values ​​and broadcast ephemeris of the plurality of target satellites through the target mobile station, and to construct an observation equation corresponding to the target mobile station according to the observation values ​​and broadcast ephemeris of the plurality of target satellites; The calculation unit is used to calculate the approximate coordinates of the target mobile 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 according to the observation equation, the approximate coordinates of the mobile station and the PPP SSR information through the target server to obtain the position coordinates and observation values ​​of the virtual reference station.

7. The network RTK device for generating a virtual reference station based on PPP SSR corrections according to claim 5, characterized in that: The acquisition module comprises: A solving unit, used for 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 using a preset extended Kalman filter strategy to obtain an ambiguity floating-point solution of the double-difference observation equation; A search and fixation unit, configured to search and fix the ambiguity floating point solution to obtain an ambiguity fixed solution, and perform baseline resolution on the ambiguity fixed solution to generate a baseline vector corresponding to the ambiguity fixed solution; A determination unit is used to determine relative position information between the target mobile station and the virtual reference station based on the baseline vector.

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

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

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

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