Correction data transmission method and system based on Beidou RDSS

Abstract

The invention discloses a correction data transmission method and system based on Beidou RDSS. The method comprises the steps that after a correction data message request sent by a remote end is received, corresponding correction data are obtained, and the correction data comprise satellite orbit deviation data, satellite clock deviation data, code deviation data, ionized layer delay data, troposphere delay data and / or base station data; performing data extraction on the corrected data, and determining a to-be-sent data segment and a first bit number corresponding to the data segment; according to the data segment and the first bit number, performing coding processing according to a set Beidou short message frame structure, and then generating a correction data transmission frame; and carrying out compression and frame splicing operation on the correction data transmission frame and then sending the correction data transmission frame. According to the scheme provided by the invention, the correction parameter is broadcasted based on the Beidou area short message, the combination of the RNSS and the RDSS can be realized, and high-precision positioning can be quickly realized.

Description

Technical Field

[0001] The present invention relates to the field of satellite navigation and positioning technology, and in particular to a correction data transmission method and system based on Beidou RDSS. Background Art

[0002] The Global Navigation Satellite System (GNSS) can provide high-quality positioning, navigation and timing (PNT) services to users around the world, and has become an important space information infrastructure. Due to the influence of various errors, the positioning accuracy provided by the satellite navigation system itself is usually only 5~10m, which cannot meet the needs of high-precision users. In order to achieve centimeter-level or even millimeter-level positioning, two precise positioning methods have been proposed, one is differential positioning, and the other is precise point positioning (PPP).

[0003] Differential positioning uses the correlation of observation errors in space and time to eliminate them. Real-time kinematic carrier phase differential positioning (RTK) technology is a representative technology. At present, RTK technology is very mature and can provide centimeter-level real-time positioning services in a local area. However, since RTK is limited by the deployment range and density of base stations, a single base station can only cover a distance of about tens of kilometers to more than one hundred kilometers. The cost of achieving wide-area coverage is very high, and it is difficult to cover areas such as the sea and desert.

[0004] Compared with differential positioning, precise point positioning (PPP) uses high-precision satellite orbit and clock products, carrier phase and pseudorange observations to achieve high-precision positioning through model correction or parameter estimation. It does not require users to set up ground reference stations by themselves, single-machine operation, positioning is not limited by the range of action, operation is flexible and low-cost, and can directly determine the high-precision position coordinates of the station under the International Terrestrial Reference Frame (ITRF). However, due to the influence of residuals such as atmospheric delay, using PPP to achieve centimeter-level positioning accuracy usually requires at least 30 minutes or even longer initialization time, and the reinitialization time after signal loss is almost as long as the initialization time, which seriously limits the application of PPP. Therefore, real-time precise point positioning (RT-PPP) is a hot research topic in the field of navigation and positioning, and will also be one of the key technologies for global real-time dynamic positioning in the future, with unlimited application prospects. Obtaining high-precision real-time satellite orbit and satellite clock products is the focus of real-time PPP.

[0005] In order to fully integrate the advantages of RTK and PPP and avoid their shortcomings, the regional / wide-area PPP-RTK technology that combines the two has emerged. The PPP-RTK enhanced service can help users obtain centimeter-level accurate position solutions in a few seconds or more than ten seconds. Compared with the convergence time of several minutes to tens of minutes without using this service, the waiting time of the positioning service is significantly shortened, and the positioning work efficiency is significantly improved. PPP-RTK generates a set of state corrections including satellite clock error, orbit error, regional ionospheric error, etc. through comprehensive estimation and modeling of base station data, and sends them to the mobile station through the Internet for position solution.

[0006] In the existing technology, the correction data required for high-precision positioning such as PPP-RTK and RTK are mainly broadcasted through the Internet, which is difficult to meet the needs of wide-area coverage, especially when the ground communication link is interfered with or cannot be covered, the correction data is difficult to transmit successfully. Summary of the invention

[0007] In order to solve the technical problem that the correction data required for existing high-precision positioning mainly relies on the Internet for broadcasting, which is difficult to meet the wide-area coverage requirements, the embodiments of the present invention provide a correction data transmission method and system based on Beidou RDSS.

[0008] The technical solution of the embodiment of the present invention is achieved as follows: The embodiment of the present invention provides a correction data transmission method based on Beidou RDSS, the method comprising: after receiving a correction data message request sent by a remote end, obtaining corresponding correction data; the correction data comprises satellite orbit deviation data, satellite clock error data, code deviation data, ionospheric delay data, tropospheric delay data and / or reference station data; extracting the correction data to determine a data segment to be sent and a first bit number corresponding to the data segment; according to the data segment and the first bit number, encoding processing is performed according to a set Beidou short message frame structure to generate a correction data transmission frame; compressing and splicing the correction data transmission frame before sending; Among them, after receiving the correction data message request sent by the remote end, the corresponding correction data is obtained, including: if the correction data message request contains the sender address and the sender address is within the baseline range of the reference station, the reference station data is obtained; if the correction data message request contains the sender address and the sender address is not within the baseline range of the reference station, the reference station data, ionospheric delay data and tropospheric delay data are obtained; if the positioning technology specified in the correction data message request is the PPP positioning technology, the satellite orbit deviation data and the satellite clock error data are obtained; if the positioning technology specified in the correction data message request is the PPP-RTK positioning technology, the satellite orbit deviation data, the satellite clock error data, the code deviation data, the ionospheric delay data and the tropospheric delay data are obtained; if the correction data message request does not contain the sender address, and the correction data message request does not specify the positioning technology, the satellite orbit deviation data, the satellite clock error data, the code deviation data, the ionospheric delay data, the tropospheric delay data and the reference station data are obtained.

[0009] In one embodiment, if the correction data message request includes a sender address and the sender address is not within the reference station baseline, then the reference station data, ionospheric delay data and tropospheric delay data are obtained, including: obtaining the reference station data of the preset altitude angle of the sender address, and the ionospheric delay data and tropospheric delay data within the preset range of the sender address.

[0010] In one embodiment, data extraction is performed on the correction data to determine a data segment to be sent and a first bit number corresponding to the data segment, including: if the correction data includes satellite orbit deviation data and satellite clock error data, the data segment to be sent includes a 6-bit satellite number, an 8-bit ephemeris data age, a 22-bit orbital plane radial correction value, a 20-bit orbital plane tangential correction value, a 20-bit orbital plane normal correction value, a 22-bit first clock error correction coefficient, a 21-bit second clock error correction coefficient, and a 27-bit third clock error correction coefficient. clock correction coefficient; if the correction data includes ionospheric delay data, the data segment to be sent includes 28 bits of starting latitude, 28 bits of ending latitude, 6 bits of latitude step, 28 bits of starting longitude, 28 bits of ending longitude, 6 bits of longitude step, 4 bits of update interval, 7 bits of ionospheric altitude, 20 bits of week seconds, and multiple 8-bit ionospheric grid points; if the correction data includes tropospheric delay data, the data segment to be sent includes 28 bits of starting latitude, 28 bits of ending latitude, 6 bits of longitude step, 4 bits of update interval, 7 bits of ionospheric altitude, 20 bits of week seconds, and multiple 8-bit ionospheric grid points. The correction data includes a latitude step of 17 bits, a starting longitude of 28 bits, an ending longitude of 28 bits, a longitude step of 6 bits, an epoch time of 20 bits, an update interval of 4 bits, and a plurality of 10-bit grid point tropospheric zenith delays; if the correction data includes code deviation data, the data segment to be sent includes a 17-bit epoch time, a 6-bit satellite number, a 4-bit number of code deviations, a plurality of 4-bit signals and tracking modes, and a plurality of 12-bit code deviations; if the correction data includes reference station data, the data segment to be sent includes a 12-bit The reference station identifier, 38-bit X coordinate, 38-bit Y coordinate, 38-bit Z coordinate, 12-bit week count, 20-bit second of week, 7-bit millisecond count, 1-bit synchronization flag, 3-bit system identifier, 6-bit number of satellites, 6-bit satellite number, 4-bit number of signals, 8-bit satellite approximate distance in milliseconds, 10-bit satellite approximate distance in milliseconds remainder, 4-bit signal identifier, 15-bit signal precise pseudorange, 22-bit signal precise phase and 6-bit signal carrier-to-noise ratio.

[0011] In one embodiment, the set Beidou short message frame structure includes a 2-bit synchronization code, a 1-bit correction data type, a 2-bit total data length, a first bit data segment and a 3-bit end code.

[0012] In one embodiment, if the correction data is satellite orbit deviation data and satellite clock error data, the 1-bit correction data type is 01; if the correction data is ionospheric delay data, the 1-bit correction data type is 02; if the correction data is tropospheric delay data, the 1-bit correction data type is 03; if the correction data is code deviation data, the 1-bit correction data type is 04; if the correction data is reference station data, the 1-bit correction data type is 05; if the correction data is none of the above, the 1-bit correction data type is 00.

[0013] In one embodiment, the correction data transmission frame is compressed and spliced ​​before being sent, including: after compressing the correction data transmission frame, the correction data is spliced ​​and sent according to the data volume of the correction data and the single maximum communication data transmission volume of the Beidou short message.

[0014] In one embodiment, obtaining corresponding correction data includes: obtaining corresponding correction data from an online website of a monitoring center, a ground-based augmentation system, a satellite-based augmentation system and / or low-orbit communication.

[0015] An embodiment of the present invention also provides a correction data transmission system based on Beidou RDSS, comprising: a processor and a memory for storing a computer program that can be run on the processor; wherein the processor executes the steps of the above-mentioned method when running the computer program.

[0016] An embodiment of the present invention further provides a storage medium, in which a computer program is stored. When the computer program is executed by a processor, the steps of the above method are implemented.

[0017] The correction data transmission method and system based on Beidou RDSS provided in the embodiment of the present invention obtains corresponding correction data after receiving a correction data message request sent by a remote end; the correction data includes satellite orbit deviation data, satellite clock error data, code deviation data, ionospheric delay data, tropospheric delay data and / or reference station data; data extraction is performed on the correction data to determine the data segment to be sent and the first bit number corresponding to the data segment; according to the data segment and the first bit number, after encoding processing is performed according to the set Beidou short message frame structure, a correction data transmission frame is generated; the correction data transmission frame is compressed and framed before being sent. The solution provided by the present invention is based on the Beidou regional short message broadcast correction parameters, which can realize the combination of RNSS and RDSS and quickly achieve high-precision positioning. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1It is a flowchart of a correction data transmission method based on Beidou RDSS according to an embodiment of the present invention; Figure 2 1 is a diagram showing the internal structure of a computer device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0019] The present invention will be described in further detail below with reference to the accompanying drawings and embodiments.

[0020] The embodiment of the present invention provides a correction data transmission method based on Beidou RDSS, such as Figure 1 As shown, the method includes: Step 101: after receiving a correction data message request sent by a remote end, obtaining corresponding correction data; the correction data includes satellite orbit deviation data, satellite clock error data, code deviation data, ionospheric delay data, tropospheric delay data and / or reference station data; Step 102: extracting the corrected data to determine a data segment to be sent and a first bit number corresponding to the data segment; Step 103: Generate a correction data transmission frame after encoding according to the data segment and the first bit number in accordance with a set Beidou short message frame structure; Step 104: compress and splice the corrected data transmission frame and then send it.

[0021] In order to realize fast and high-precision positioning such as PPP-RTK, RTK, PPP, etc. in a wide area, this embodiment broadcasts correction parameters based on Beidou regional short messages, realizes the combination of RNSS and RDSS, and quickly realizes high-precision positioning. In order to solve the technical problem that Beidou short messages are limited in data transmission, that is, the technical problem that the transmission volume and communication frequency of Beidou short messages are limited, this embodiment also encodes and compresses the correction data.

[0022] Specifically, this embodiment can obtain corresponding correction data from the online website of the monitoring center, the ground-based augmentation system, the satellite-based augmentation and / or the low-orbit communication. After obtaining the correction data, this embodiment will perform a rationality check on the correction data, and transmit it after the check passes.

[0023] If the correction data message request contains the sender address and the sender address is within the reference station baseline, the reference station data MSG5 is obtained; if the correction data message request contains the sender address and the sender address is not within the reference station baseline, the reference station data MSG5, ionospheric delay data MSG2 and tropospheric delay data MSG3 are obtained; if the positioning technology specified in the correction data message request is the PPP positioning technology, the satellite orbit deviation data and satellite clock error data MSG1 are obtained; if the correction data message request contains the sender address and the sender address is not within the reference station baseline, the reference station data MSG5, ionospheric delay data MSG2 and tropospheric delay data MSG3 are obtained; if the positioning technology specified in the correction data message request is the PPP positioning technology, the satellite orbit deviation data and satellite clock error data MSG1 are obtained; If the designated positioning technology is PPP-RTK positioning technology, satellite orbit deviation data and satellite clock error data MSG1, code deviation data MSG4, ionospheric delay data MSG2 and tropospheric delay data MSG3 are obtained; if the correction data message request does not contain the sender address and the correction data message request does not specify the positioning technology, satellite orbit deviation data and satellite clock error data MSG1, code deviation data MSG4, ionospheric delay data MSG2, tropospheric delay data MSG3 and reference station data MSG5 are obtained.

[0024] Furthermore, if the correction data message request includes a sender address and the sender address is not within the reference station baseline range, the reference station data of the preset altitude angle of the sender address, and the ionospheric delay data and tropospheric delay data within the preset range of the sender address are obtained.

[0025] Specifically, referring to Table 1, in this embodiment, if the correction data includes satellite orbit deviation data and satellite clock error data MSG1, the data segment to be sent includes a 6-bit satellite number, an 8-bit ephemeris data age, a 22-bit orbital plane radial correction value, a 20-bit orbital plane tangential correction value, a 20-bit orbital plane normal correction value, a 22-bit first clock error correction coefficient, a 21-bit second clock error correction coefficient, and a 27-bit third clock error correction coefficient;

[0026] Referring to Table 2, if the correction data includes ionospheric delay data MSG2, the data segment to be sent includes 28-bit starting latitude, 28-bit ending latitude, 6-bit latitude step, 28-bit starting longitude, 28-bit ending longitude, 6-bit longitude step, 4-bit update interval, 7-bit ionospheric altitude, 20-bit second of week, and multiple 8-bit ionospheric grid points;

[0027] Referring to Table 3, if the correction data includes tropospheric delay data MSG3, the data segment to be sent includes 28-bit starting latitude, 28-bit ending latitude, 6-bit latitude step, 28-bit starting longitude, 28-bit ending longitude, 6-bit longitude step, 20-bit epoch time, 4-bit update interval, and multiple 10-bit grid point tropospheric zenith delays;

[0028] Referring to Table 4, if the correction data includes code deviation data MSG4, the data segment to be sent includes 17 bits of epoch time, 6 bits of satellite number, 4 bits of code deviation number, multiple 4 bits of signal and tracking mode and multiple 12 bits of code deviation;

[0029] Referring to Table 5, if the correction data includes reference station data MSG5, the data segment to be sent includes a 12-bit reference station identifier, a 38-bit X coordinate, a 38-bit Y coordinate, a 38-bit Z coordinate, a 12-bit week count, a 20-bit second in the week, a 7-bit millisecond count, a 1-bit synchronization flag, a 3-bit system identifier, a 6-bit satellite number, a 6-bit satellite number, a 4-bit signal number, an 8-bit satellite approximate distance in milliseconds, a 10-bit satellite approximate distance in milliseconds remainder, a 4-bit signal identifier, a 15-bit signal precise pseudorange, a 22-bit signal precise phase, and a 6-bit signal carrier-to-noise ratio:

[0030] The data segment to be sent and the first bit number of the data segment can be determined through the above content. After determining the data segment to be sent and the first bit number of the data segment, a correction data transmission frame can be generated according to the set Beidou short message frame structure.

[0031] Specifically, referring to Table 6, the set Beidou short message frame structure includes a 2-bit synchronization code, a 1-bit correction data type, a 2-bit total data length, a first bit number of data segments, and a 3-bit end code:

[0032] Wherein, referring to Table 7, if the correction data is satellite orbit deviation data and satellite clock error data, the correction data type of the 1 bit is 01; if the correction data is ionospheric delay data, the correction data type of the 1 bit is 02; if the correction data is tropospheric delay data, the correction data type of the 1 bit is 03; if the correction data is code deviation data, the correction data type of the 1 bit is 04; if the correction data is reference station data, the correction data type of the 1 bit is 05; if the correction data is not the above case, the correction data type of the 1 bit is 00:

[0033] After compressing the correction data transmission frame, this embodiment can perform a frame splicing operation on the correction data and send it according to the data volume of the correction data and the single maximum communication data transmission volume of the Beidou short message.

[0034] Below, this solution will be described in detail with a specific embodiment.

[0035] Step S1: receiving a correction data message request from a receiver terminal, and determining whether a sender address exists in the message information; In step S1, a correction data message request is received from a mobile station or terminal, and it is determined whether the message contains the approximate position A (x, y, z) of the mobile station or terminal. Upon receiving the request, the local receiver frames the correction data and transmits it to the mobile station or terminal that made the request, supporting it to quickly implement high-precision positioning processing, while recording the uplink inbound transmission frequency point. The user end performs PPP-RTK positioning or RTK positioning according to the type of data received.

[0036] Step S2: The local receiver obtains correction data, including satellite orbit deviation (i.e., satellite orbit deviation data), satellite clock error (i.e., satellite clock error data), ionospheric delay (i.e., ionospheric delay data), tropospheric delay (i.e., tropospheric delay data), reference station (i.e., reference station data), etc., and performs rationality check on the data; In step S2, the local receiver obtains the latest precise ephemeris, ionospheric parameters, tropospheric parameters and other correction data in real time through communication and other means, including but not limited to: online website of monitoring center, ground-based augmentation system, satellite-based augmentation, low-orbit communication, etc. In step S2, the obtained data will also be checked for rationality in a conventional way.

[0037] Step S3: Extract and encode the precise orbits, ionospheric parameters, tropospheric parameters, reference stations and other information of different satellites. If there is an approximate position, the data is processed by satellite selection and data interpolation, and only the correction data within a certain range of the receiver terminal is sent; when there is an approximate position and it is within the baseline range of the reference station, only the RTK correction parameters are broadcast by default; if there is no sender address, the precise orbit, ionospheric parameters, tropospheric parameters and other correction data are compressed and sent; In step S3, the precise orbits, ionospheric parameters, tropospheric parameters, base station data and other information of different satellites are extracted and encoded. The correction data are mainly divided into satellite orbit correction numbers (i.e. satellite orbit deviation data), clock errors (i.e. satellite clock error data), code errors (i.e. code deviation data), ionospheric delays (i.e. ionospheric delay data), tropospheric delays (i.e. tropospheric delay data), base station data, etc. If there is an approximate position A and it is within the base station baseline, only the RTK correction parameter MSG5 is broadcast by default; if the message request specifies PPP, MSG1 is broadcast; if the message request broadcasts PPP-RTK correction parameters, MSG1, MSG2, MSG3, and MSG4 are broadcast; if there is no clear instruction, the PPP-RTK correction parameters are broadcast by default.

[0038] In addition, in step S3, there are the following two data sending situations: ① If the approximate location of the sender is not obtained, all the correction parameters at the current moment are transmitted according to the above encoding rules; ② After obtaining the approximate position A of the sender, the correction data is processed, and the differential correction information of the GNSS satellites above the position A and the ionosphere and troposphere correction parameters are broadcast in a targeted manner. The data volume is reduced in the following manner: 1) When selecting satellites, satellite orbits and clock corrections are sent only for satellites that meet a certain altitude angle, for example, satellites with an altitude angle below 5° are excluded; 2) Transmit the ionospheric and tropospheric delay parameters of the current certain area, and use the conventional interpolation method to calculate the ionospheric grid value within a certain range of position A.

[0039] According to the Beidou short message communication requirements, the encoding is performed according to the following rules: 1) RD data communication frame structure

[0040]

[0041]

[0042] 2) MSG1 data segment The MSG1 data segment is used to transmit satellite orbit and clock corrections. Since the range observation is insensitive to changes in the tangential and normal directions, the radial accuracy of the orbit is better than the normal and tangential directions. Therefore, based on RDSS communication limitations, the orbit correction value and correction value change rate of a satellite are not fully broadcast;

[0043] 3) MSG2 data segment (ionospheric delay data)

[0044] 4) MSG3 data segment (tropospheric delay data)

[0045] 5) MSG4 data segment (code deviation data)

[0046] 5) MSG5 data segment (reference station data)

[0047] Step S4: Calculate the length of the correction data to be sent at the current moment, compress the correction data using a compression algorithm, and perform frame splicing after compression is completed; In step S4, the length of the correction data to be sent at the current moment is calculated, and the correction data is compressed using a compression algorithm. After the compression is completed, the frame is assembled based on the data content and the maximum single communication data transmission volume of RD.

[0048] Step S5: According to the RDSS communication frequency and the data transmission requirements, the data frame is sent once or multiple times.

[0049] In step S5, single transmission or packet transmission is selected according to the data size.

[0050] The specific effects of this embodiment are as follows: (1) Based on the correction data communication of Beidou short message RDSS, the RNSS and RDSS are combined to quickly achieve high-precision positioning such as PPP-RTK and RTK; (2) The correction data information used to achieve high-precision positioning can be flexibly selected, and all data can be standardizedly encoded; (3) Formulate correction data types and coding formats suitable for Beidou RDSS transmission to meet the needs of wide-area users for high-precision positioning enhancement information.

[0051] The correction data transmission method based on Beidou RDSS provided in an embodiment of the present invention obtains corresponding correction data after receiving a correction data message request sent by a remote end; the correction data includes satellite orbit deviation data, satellite clock error data, code deviation data, ionospheric delay data, tropospheric delay data and / or reference station data; data extraction is performed on the correction data to determine the data segment to be sent and the first bit number corresponding to the data segment; according to the data segment and the first bit number, after encoding processing is performed according to the set Beidou short message frame structure, a correction data transmission frame is generated; the correction data transmission frame is compressed and framed before being sent. The solution provided by the present invention is based on the Beidou regional short message broadcast correction parameters, which can realize the combination of RNSS and RDSS and quickly achieve high-precision positioning.

[0052] In order to implement the method of an embodiment of the present invention, an embodiment of the present invention also provides a correction data transmission system based on Beidou RDSS, including: a processor and a memory for storing a computer program that can be run on the processor; wherein, when the processor is used to run the computer program, the steps of the above-mentioned method are executed.

[0053] The above-mentioned system provided in this embodiment belongs to the same concept as the above-mentioned method embodiment. The specific implementation process thereof is detailed in the method embodiment and will not be repeated here.

[0054] In order to implement the method of the embodiment of the present invention, the embodiment of the present invention also provides a computer program product, which includes computer instructions, and the computer instructions are stored in a computer-readable storage medium. The processor of the computer device reads the computer instructions from the computer-readable storage medium, and the processor executes the computer instructions, so that the computer device performs the steps of the above method.

[0055] Based on the hardware implementation of the above program modules, and in order to implement the method of the embodiment of the present invention, the embodiment of the present invention further provides an electronic device (computer device). Specifically, in one embodiment, the computer device may be a terminal, and its internal structure diagram may be as follows: Figure 2As shown. The computer device includes a processor A01, a network interface A02, a display screen A04, an input device A05 and a memory (not shown in the figure) connected through a system bus. Among them, the processor A01 of the computer device is used to provide computing and control capabilities. The memory of the computer device includes an internal memory A03 and a non-volatile storage medium A06. The non-volatile storage medium A06 stores an operating system B01 and a computer program B02. The internal memory A03 provides an environment for the operation of the operating system B01 and the computer program B02 in the non-volatile storage medium A06. The network interface A02 of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor A01, the method of any one of the above embodiments is implemented. The display screen A04 of the computer device can be a liquid crystal display screen or an electronic ink display screen, and the input device A05 of the computer device can be a touch layer covered on the display screen, or a key, trackball or touchpad set on the computer device housing, or an external keyboard, touchpad or mouse, etc.

[0056] Those skilled in the art will understand that Figure 2 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0057] The device provided by the embodiment of the present invention includes a processor, a memory, and a program stored in the memory and executable on the processor. When the processor executes the program, the method of any one of the above embodiments is implemented.

[0058] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0059] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0060] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0061] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0062] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0063] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. The memory is an example of a computer-readable medium.

[0064] Computer readable media include permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. Information can be computer readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, magnetic disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer readable media does not include temporary computer readable media (transitory media), such as modulated data signals and carrier waves.

[0065] It can be understood that the memory of the embodiment of the present invention can be a volatile memory or a non-volatile memory, and can also include both volatile and non-volatile memories. Among them, the non-volatile memory can be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a magnetic random access memory (FRAM), a flash memory, a magnetic surface memory, an optical disc, or a compact disc read-only memory (CD-ROM); the magnetic surface memory can be a disk memory or a tape memory. The volatile memory can be a random access memory (RAM), which is used as an external cache. By way of example and not limitation, many forms of RAM are available, such as static random access memory (SRAM), synchronous static random access memory (SSRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDRSDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous link dynamic random access memory (SLDRAM, SyncLink Dynamic Random Access Memory), and direct RAMbus random access memory (DRRAM, Direct Rambus Random Access Memory).The memories described in the embodiments of the present invention are intended to include, but are not limited to, these and any other suitable types of memories.

[0066] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0067] The above are only embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included within the scope of the claims of the present application.

Claims

1. A correction data transmission method based on Beidou RDSS, characterized in that: The method comprises: After receiving a correction data message request sent by a remote end, obtaining corresponding correction data; the correction data includes satellite orbit deviation data, satellite clock error data, code deviation data, ionospheric delay data, tropospheric delay data and / or reference station data; Extracting the corrected data to determine a data segment to be sent and a first number of bits corresponding to the data segment; Generate a correction data transmission frame after encoding according to the data segment and the first number of bits in accordance with a set Beidou short message frame structure; Compressing and splicing the corrected data transmission frame before sending it; After receiving the correction data message request sent by the remote end, the corresponding correction data is obtained, including: If the correction data message request includes a sender address and the sender address is within the reference station baseline range, obtaining reference station data; If the correction data message request includes a sender address and the sender address is not within the reference station baseline, obtaining reference station data, ionospheric delay data, and tropospheric delay data; If the positioning technology specified in the correction data message request is the PPP positioning technology, obtaining satellite orbit deviation data and satellite clock error data; If the positioning technology specified in the correction data message request is the PPP-RTK positioning technology, satellite orbit deviation data, satellite clock error data, code deviation data, ionospheric delay data and tropospheric delay data are obtained; If the correction data message request does not include the sender address and the correction data message request does not specify the positioning technology, then the satellite orbit deviation data, satellite clock error data, code deviation data, ionospheric delay data, tropospheric delay data and reference station data are obtained.

2. The correction data transmission method based on Beidou RDSS according to claim 1, characterized in that: If the correction data message request includes a sender address and the sender address is not within the reference station baseline range, obtaining reference station data, ionospheric delay data, and tropospheric delay data includes: Acquire the reference station data of the preset altitude angle of the sender address, and the ionospheric delay data and the tropospheric delay data within the preset range of the sender address.

3. The correction data transmission method based on Beidou RDSS according to claim 1, characterized in that: Extracting the corrected data to determine a data segment to be sent and a first number of bits corresponding to the data segment includes: If the correction data includes satellite orbit deviation data and satellite clock error data, the data segment to be sent includes a 6-bit satellite number, an 8-bit ephemeris data age, a 22-bit orbital plane radial correction value, a 20-bit orbital plane tangential correction value, a 20-bit orbital plane normal correction value, a 22-bit first clock error correction coefficient, a 21-bit second clock error correction coefficient, and a 27-bit third clock error correction coefficient; If the correction data includes ionospheric delay data, the data segment to be sent includes 28 bits of starting latitude, 28 bits of ending latitude, 6 bits of latitude step, 28 bits of starting longitude, 28 bits of ending longitude, 6 bits of longitude step, 4 bits of update interval, 7 bits of ionospheric altitude, 20 bits of seconds in the week, and multiple 8 bits of ionospheric grid points; If the correction data includes tropospheric delay data, the data segment to be sent includes 28 bits of starting latitude, 28 bits of ending latitude, 6 bits of latitude step, 28 bits of starting longitude, 28 bits of ending longitude, 6 bits of longitude step, 20 bits of epoch time, 4 bits of update interval, and multiple 10 bits of grid point tropospheric zenith delay; If the correction data includes code deviation data, the data segment to be sent includes 17 bits of epoch time, 6 bits of satellite number, 4 bits of code deviation number, multiple 4 bits of signal and tracking mode and multiple 12 bits of code deviation; If the correction data includes reference station data, the data segment to be sent includes a 12-bit reference station identifier, a 38-bit X coordinate, a 38-bit Y coordinate, a 38-bit Z coordinate, a 12-bit week count, a 20-bit second in the week, a 7-bit millisecond count, a 1-bit synchronization flag, a 3-bit system identifier, a 6-bit number of satellites, a 6-bit satellite number, a 4-bit number of signals, an 8-bit integer number of milliseconds of the satellite approximate distance, a 10-bit millisecond remainder of the satellite approximate distance, a 4-bit signal identifier, a 15-bit signal precise pseudorange, a 22-bit signal precise phase, and a 6-bit signal carrier-to-noise ratio.

4. The correction data transmission method based on Beidou RDSS according to claim 3 is characterized in that: The set Beidou short message frame structure includes a 2-bit synchronization code, a 1-bit correction data type, a 2-bit total data length, a first bit number of data segments and a 3-bit end code.

5. The correction data transmission method based on Beidou RDSS according to claim 4 is characterized in that: If the correction data is satellite orbit deviation data and satellite clock error data, the 1-bit correction data type is 01; if the correction data is ionospheric delay data, the 1-bit correction data type is 02; if the correction data is tropospheric delay data, the 1-bit correction data type is 03; if the correction data is code deviation data, the 1-bit correction data type is 04; if the correction data is reference station data, the 1-bit correction data type is 05; if the correction data is none of the above, the 1-bit correction data type is 00.

6. The correction data transmission method based on Beidou RDSS according to claim 1, characterized in that: The corrected data transmission frame is compressed and framed before being sent, comprising: After compressing the correction data transmission frame, the correction data is framed and sent according to the data volume of the correction data and the single maximum communication data transmission volume of the Beidou short message.

7. The correction data transmission method based on Beidou RDSS according to claim 1, characterized in that: Get the corresponding correction data, including: Obtain the corresponding correction data from the monitoring center online website, ground-based augmentation system, satellite-based augmentation and / or low-orbit communication.

8. A correction data transmission system based on Beidou RDSS, characterized in that: include: A processor and a memory for storing a computer program that can be run on the processor; wherein, when the processor is used to run the computer program, the steps of the method according to any one of claims 1 to 7 are executed.

9. A storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

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