Portable PPP-B2b Beidou positioning and timing device

Abstract

The invention discloses a portable PPP-B2b Beidou positioning and timing device. The portable PPP-B2b Beidou positioning and timing device comprises a GNSS (Global Navigation Satellite System) receiver module, a resolving module and a data resolving precision evaluation module, the GNSS receiver module is used for obtaining an original navigation message and an observed quantity, the resolving module comprises a microcontroller, a serial port communication unit and a clock unit, the original navigation message and the observed quantity are output to the microcontroller in a real-time data flow mode, and the microcontroller receives data and then arranges the data to generate real-time precise track data; position and time calculation is carried out through the data calculation precision evaluation module, position information is sent out through the serial port communication unit, a clock error sequence is forecasted, and the frequency of the clock unit and output of second signals are controlled. The positioning time service device with the precision of static centimeter level, dynamic decimeter level and superior to nanosecond level is realized, the requirements of precise positioning and time synchronization of electric power services such as intelligent inspection and personnel safety operation on a scene without ground communication are met, and an automatic real-time solution is provided.

Description

Technical Field

[0001] The invention relates to the technical field of time service, positioning and timing, and in particular to a portable PPP-B2b Beidou positioning and timing device. Background Art

[0002] At present, the BeiDou satellite navigation system is a global satellite navigation system independently developed and operated by my country. Together with the GPS of the United States, GLONASS of Russia and GALILEO of the European Union, it is collectively referred to as the global satellite navigation system. BDS is increasingly widely used in various fields due to its high accuracy, high speed, all-weather operation, high degree of automation, no need for line of sight between stations, high-precision positioning and timing, and many other advantages.

[0003] As the level of intelligence of my country's power system continues to improve, the requirements for positioning and time synchronization accuracy are getting higher and higher. Real-time high-precision positioning and its time synchronization technology have attracted much attention, and precise point positioning (PPP) is particularly important. However, network data communication is currently the main bottleneck restricting the practical application of this technology in my country, and how to solve this bottleneck problem is a difficult point in research. Summary of the invention

[0004] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a portable PPP-B2b Beidou positioning and timing device.

[0005] The objective of the present invention is achieved through the following technical solutions: The present invention provides a portable PPP-B2b Beidou positioning and timing device, comprising: a GNSS receiver module, a solution module and a data solution accuracy evaluation module; the GNSS receiver module comprises a BDS / GNSS antenna and a high-precision BDS / GNSS positioning unit, the GNSS receiver module receives BDS / GNSS navigation satellite signals through the BDS / GNSS antenna, and performs capture, tracking, bit synchronization, frame synchronization and decoding processing through the high-precision BDS / GNSS positioning unit to obtain original navigation messages and obtain observation quantities at the measurement time. The observed quantities include pseudorange, carrier phase, and Doppler. The solution module includes a microcontroller, a serial communication unit, and a clock unit. The original navigation message and the observed quantities are output to the microcontroller in the form of a real-time data stream. After receiving the data, the microcontroller organizes the data, processes the broadcast ephemeris and the broadcast SSR correction number, and generates real-time precise orbit data; the position and time are solved by the data solution accuracy evaluation module, the position information is sent out through the serial communication unit, and the clock difference sequence is predicted at the same time to obtain the steering quantity, which is used to control the frequency of the clock unit and the output of the second signal.

[0006] Furthermore, the data solution accuracy assessment module performs the location and time solution including the following steps: S1, initialize, the original number , location covariance ; Calculate the receiver position of the initial position using SPP , Receiver clock error and fuzziness ; S2, original name When Then proceed to step S3, where is the positioning threshold; S3. Calculate the i Receiver clock error of BeiDou-3 satellites ,in For the i The wavelength of the BeiDou-3 satellites, For the i The coordinates of the BeiDou-3 satellites. For the i The phase observation values ​​of the BeiDou-3 satellites, For the i The error correction of the BeiDou III satellites and calculation of the first increment ,calculate the median of , where the first increment is i The third generation Beidou satellite and the i -The absolute value of the difference in receiver clock error of one BeiDou-3 satellite; S4. Calculate the second increment , if the second increment , then delete the kth satellite, where is the receiver deviation threshold, and the second increment is the absolute value of the difference between the first increment and the median of the first increment.

[0007] Preferably, when using precise orbit and clock products The value is 5~10cm, It is used to detect cycle slips or gross errors of 1 or 0.5 cycles, with a value of 6~8cm.

[0008] Furthermore, it also includes a power supply module for converting the DC voltage to suit the different voltage requirements of each module.

[0009] Furthermore, it also includes: a Beidou observation data real-time quality control module for data integrity analysis, data gross error processing, data cycle slip detection and receiver clock jump processing; a Beidou real-time data processing module for multiple error analysis processing, real-time dynamic solution model, ambiguity estimation and error model refinement; Preferably, the Beidou observation data real-time quality control module processes data including the following steps: Step 1: first input the real-time data stream, delete the bad data therein, and form a new sequence of observation quantities. If the real-time data stream initially input is all bad data, then delete all of them and input a new real-time data stream. The new sequence of observation quantities is divided into three parts, one part is directly output to a file, one part is used to set cycle slip detection parameters, and one part is used for navigation messages. Step 2: Divide the new sequence of observations used to set cycle slip detection parameters into two parts, one of which is to first determine the cycle slips through the wide lane combination method and then remove the outliers to obtain the wide lane ambiguity, and the other is to first remove the outliers through the geometry-free combination and then determine the cycle slips to obtain the wide lane ambiguity; combine the wide lane ambiguities of the two parts, comprehensively calculate the cycle slip size of all cycle slips, then repair the cycle slips, and finally output the file; Step 3: Process the abnormal values ​​of the new sequence of observation quantities for the navigation message, generate a standardized message, and finally output the message to a file.

[0010] Preferably, the Beidou observation data real-time quality control module includes a software initialization module, a data processing module and a data output module; In the software initialization module, first select the GNSS observation file directory to determine whether the necessary products are missing. If they are missing, download the necessary products. If the download fails, terminate the program. If the download is successful, initialize BDS-B2b according to the configuration. If not missing, initialize BDS-B2b according to the configuration. Then read the observation file. If the observation file is read, enter the data output module for processing. If the observation file is not read, enter the data processing module for processing. After entering the data processing module, read an epoch information, calculate various error model corrections, and then calculate the approximate coordinates of the measuring station through SPP. Perform basic quality control on two adjacent epochs, and then perform filtering estimation to determine whether there is a gross error in the filtering. If so, remove the gross error and perform filtering estimation again. If no gross error exists, keep the current epoch information and filtering estimation results, and re-read the observation file. After entering the data output module, the position file, the model correction information of each epoch and the observation residual file are solved, and then the program is terminated. The residual files include: ZTA, receiver species difference, ISB file, kml file, drawing image file and ambiguity file of each satellite.

[0011] The beneficial effects of the present invention are: 1) The convergence time of BeiDou III PPP-B2b is 20 min. The static positioning accuracy of the present invention is better than 2 cm and the elevation is better than 3 cm. The dynamic positioning accuracy is better than 5 cm and the elevation is better than 8 cm. The timing accuracy is better than 1 ns (1σ).

[0012] 2) The present invention optimizes the error model and data quality control method in real-time precise positioning and timing, reasonably establishes the algorithm model and hardware equipment based on PPP-B2b, and constructs a precise positioning and timing prototype system model suitable for the power grid system, so as to achieve a positioning and timing device with static centimeter-level, dynamic decimeter-level and better than nanosecond-level accuracy. In order to meet the needs of precise positioning and time synchronization in scenarios without ground communication for power services such as intelligent inspection and safe operation of personnel, an all-weather, automatic, high-precision and real-time solution is provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 A schematic diagram of the architecture of a portable PPP-B2b Beidou positioning and timing device according to an embodiment of the present invention; Figure 2 A schematic diagram of the functional composition of a portable PPP-B2b Beidou positioning and timing device according to an embodiment of the present invention; Figure 3 A schematic diagram of a processing flow of a Beidou observation data real-time quality control module of a portable PPP-B2b Beidou positioning and timing device according to an embodiment of the present invention; Figure 4 This is a functional schematic diagram of a Beidou observation data real-time quality control module of a portable PPP-B2b Beidou positioning and timing device according to an embodiment of the present invention; Figure 5 A schematic diagram of the system software module composition of a portable PPP-B2b Beidou positioning and timing device according to an embodiment of the present invention; Figure 6 A schematic diagram of the structure of a portable PPP-B2b Beidou positioning and timing device according to an embodiment of the present invention; Figure 7 It is a schematic diagram of static test results of a portable PPP-B2b Beidou positioning and timing device according to an embodiment of the present invention; Figure 8 This is a schematic diagram of dynamic test results of a portable PPP-B2b Beidou positioning and timing device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0014] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0015] The present invention provides a portable PPP-B2b Beidou positioning and timing device. At present, PPP is limited by the orbit and clock accuracy of the broadcast ephemeris, and mainly uses the post-precision orbit / clock products provided by a third party (such as MEGX) for precise single-point positioning processing. With the current demand for high-precision real-time single-point positioning in fields such as smart cities, precise machine control, and traffic driving, the BDS-3 system broadcasts the space signal PPP-B2b used to provide precise single-point positioning services through GEO satellites as a data broadcast channel. Unlike the existing satellite-based augmentation system (SBAS) that mainly acts on pseudo-range enhancement, the orbit clock correction number modulated on the Beidou PPP-B2b signal uses the calculation method of the carrier phase during calculation, so it has higher correction accuracy. By using the precise orbit / clock correction number provided by PPP-B2b and the predicted orbit / clock correction provided by the existing broadcast ephemeris, users can achieve real-time PPP accuracy of static centimeters and dynamic decimeters after 20 to 30 minutes of convergence. At the same time, the precise single-point positioning service of the Beidou system not only provides the precise orbit / clock correction of the Beidou satellite, but also currently provides the precise orbit / clock correction information of the GPS satellite. In the future, it will further provide the precise orbit / clock correction information of other GNSS systems to provide services for users in my country and surrounding areas. The purpose of the present invention is to design and develop a lightweight Beidou-3 PPP-B2b precise positioning and timing device that meets the special needs of electricity, by optimizing the error model and data quality control method in real-time precise positioning and timing, reasonably establishing an algorithm model and hardware equipment based on PPP-B2b, and constructing a precise positioning and timing prototype system model suitable for the power grid system, so as to achieve a positioning and timing device with an accuracy of static centimeters, dynamic decimeters and better than nanoseconds, and to meet the needs of intelligent inspection, personnel safety operation and other power services for precise positioning and time synchronization in scenarios without ground communication, and provide an all-weather, automatic, high-precision, real-time solution. On the one hand, considering the needs of power supply and fixation convenience of the device, on the other hand, the device is in harsh environments such as electromagnetic interference, vibration, low temperature / high temperature, lightning, rain, strong wind, dust, etc. Therefore, the device must not only complete the functions it must perform, but also carefully consider various aspects such as power consumption, volume, weight, overall design, module selection, hardware processing, waterproofing, heat dissipation, and thermal insulation to ensure the long-term stable operation of the device and complete high-precision positioning and timing functions without ground communication support.

[0016] For example, a portable PPP-B2b Beidou positioning and timing device, the schematic diagram of which is as follows Figure 1 As shown, by installing multiple portable PPP-B2b positioning and timing devices, all visible BDS / GNSS satellites are continuously observed, and the local coordinate position and timing output are solved in real time. It solves the problem of the need for precise positioning and time synchronization in scenarios without ground communication for power services such as smart power inspection and safe operation of personnel, including: GNSS receiver module, solution module and data solution accuracy assessment module. The GNSS receiver module includes a BDS / GNSS antenna and a high-precision BDS / GNSS positioning unit. The high-precision BDS / GNSS positioning unit includes a radio frequency front end and a baseband processing chip. The GNSS receiver module receives BDS / GNSS navigation satellite signals through the BDS / GNSS antenna, and performs capture, tracking, bit synchronization, frame synchronization and decoding processing through the high-precision BDS / GNSS positioning unit to obtain the original navigation message and obtain the observation amount at the measurement time. The observation amount includes pseudorange , carrier phase, Doppler, the solution module includes a microcontroller, a serial communication unit and a clock unit, and the original navigation message and the observed value are output to the microcontroller in the form of a real-time data stream. The microcontroller can be a single-chip microcomputer, ARM, FPGA, DSP, etc. according to the functional requirements, and is used to complete some configuration, control and format conversion functions. After receiving the data, the microcontroller organizes the data, processes the broadcast ephemeris and the broadcast SSR correction number, and generates real-time precise orbit data. The data solution accuracy evaluation module solves the position and time, and sends the position information through the serial communication unit. The serial communication unit is used for the data output of the positioning and timing results, and at the same time predicts the clock difference sequence to obtain the steering amount, which is used to control the frequency of the clock unit and the output of the second signal. It also includes a power supply module, which can generally be realized by a power management IC, and is used to convert the DC voltage to meet the different voltage requirements of each module. The clock module can use active or passive crystal oscillators because the microcontroller does not have high requirements for clock accuracy and stability. Considering the power consumption, special processing circuits are used to ensure the stability of the system. The housing has an IP67 protection level and is able to work normally in harsh environments such as corona protection, lightning protection, dust and water resistance, and good heat dissipation. The specific structural diagram is shown below. Figure 6 shown.

[0017] Specifically, the software of the positioning and timing device of the present invention uses a new precision timing data quality control algorithm independently developed. Cycle slip detection and repair is an extremely important issue in data preprocessing during relative positioning. Only by effectively detecting and repairing cycle slips can we lay the foundation for correctly resolving ambiguities and obtaining high-precision positioning results. Traditional cycle slip detection algorithms, such as the TurboEdit method, have good cycle slip repair effects and mature algorithms, but their calculations are relatively complex and are only suitable for use with dual-frequency data. In addition, TurboEdit cannot detect the situation where the cycle slips on two frequency points are consistent, and other methods need to be combined.

[0018] Beidou observation data is greatly affected by abnormal observation values ​​or ionosphere abnormalities. Observations containing gross errors will lead to phenomena such as the inability of the filter to converge stably and divergence. Therefore, real-time and high-precision Beidou data processing must strictly consider the quality of carrier observation data and effectively control it. The ground receiver moves at a low speed relative to the navigation satellite, and the ionosphere changes little at adjacent observation times. The use of ionospheric residuals can effectively detect small cycle slips or gross errors in the carrier. Due to the large difference in the ionosphere at different observation times under ionospheric anomalies, using ionospheric residuals to detect satellite cycle slips observed by the receiver is not a very effective method. Therefore, only the HMW (Hatch-Melbourne-Wübbena) combination that is not affected by the ionosphere can be used to detect some larger cycle slips. We use the overall jump value of the receiver clock error as an indicator to control the quality of Beidou data. If the receiver clock error estimated by a certain satellite has a large jump, it is considered that the carrier observation value has a cycle slip or gross error phenomenon. The data solution accuracy evaluation module performs position and time solution including the following steps: S1, initialization, when the initial number , location covariance ; Calculate the receiver position of the initial position using SPP , Receiver clock error and fuzziness ;S2, the original name When Then proceed to step S3, where is the positioning threshold; S3, calculate the i Receiver clock error of BeiDou-3 satellites ,in For the i The wavelength of the BeiDou-3 satellites, For the i The coordinates of the BeiDou-3 satellites. For the i The phase observation values ​​of the BeiDou-3 satellites, For the i The error correction of the BeiDou III satellites and calculation of the first increment ,calculate the median of , where the first increment is i The third generation Beidou satellite and the i -The absolute value of the difference in receiver clock error of 1 BeiDou III satellite; S4, calculate the second increment , if the second increment , then delete the kth satellite, where is the receiver bias threshold, and the second increment is the absolute value of the difference between the first increment and the median of the first increment. The value is 5~10cm, It is used to detect 1 or 0.5 cycle slip or gross error, with a value of 6~8cm.

[0019] Exemplarily, the system software module composition diagram of the present invention is as follows: Figure 5 As shown, it includes: Beidou observation data real-time quality control module, which is used for data integrity analysis, data gross error processing, data cycle slip detection and receiver clock jump processing; Beidou real-time data processing module, which is used for various error analysis and processing, real-time dynamic solution model, ambiguity estimation and error model refinement; data solution accuracy assessment module, which is used for position and time information solution, accuracy self-assessment analysis and anti-error solution. The error analysis mainly includes the accuracy assessment of real-time orbit and clock error; modeling and correction of ionospheric error and tropospheric error in the transmission path; correction of relativistic effect, error correction of satellite and receiver phase center, and correction of antenna phase winding; as well as modeling and correction of solid tide and sea tide of the measuring station; high-precision time frequency maintenance and rapid recovery: after the signal is interrupted, the time maintenance mainly relies on the time scale established by the Beidou atomic clock as a reference, and at the same time, the forecast value of the data link before the interruption is combined for comprehensive analysis to generate the clock control amount and maintain the time frequency. Since the data collected by BDS in real time is more complex than the data after the event and inevitably contains more cycle slips and gross errors, these anomalies will cause the accuracy of real-time Beidou differential positioning to drop rapidly. In addition, due to the poor stability of the BDS receiver clock, when the time deviation between the receiver clock and the satellite clock is greater than a certain value, the observed data often jumps, and the jumping second phenomenon will greatly affect the accuracy of the differential analysis. In addition, the observed data often has large multipath errors due to the influence of the ground environment. These cycle slips, gross errors, jumping seconds and multipath errors in the observed data will cause positioning errors in Beidou data observations, and even affect the normal positioning and timing services of the equipment. The research on the rapid recovery technology of time and frequency is mainly based on the application needs of users. After the Beidou signal link is restored, it is restored by instantaneous phase adjustment or by adjusting the frequency.

[0020] Specifically, the functional composition diagram of the present invention is as follows Figure 2 As shown in the figure, the data acquisition layer includes receiver observation data, PPP-B2b correction numbers and navigation ephemeris data sources; the data calculation layer includes a series of data storage areas such as temporary data area, data decoding, data analysis and processing, as well as areas for business rule definition and maintenance management. The data in these areas will jointly support the data storage, analysis and business applications of various terminals; data monitoring and delivery: used to support users' applications such as device identification, abnormal monitoring, trend prediction, statistical analysis, and data result delivery Exemplarily, the processing of the Beidou observation data real-time quality control module includes the following steps: Step 1, first input the real-time data stream, delete the bad data therein, and form a new sequence of observation quantities. If the real-time data stream initially input is all bad data, delete all of them and input a new real-time data stream. The new sequence of observation quantities is divided into three parts, one part is directly output to a file, one part is used to set cycle slip detection parameters, and one part is used for navigation messages; Step 2, divide the new sequence of observation quantities used to set cycle slip detection parameters into two parts, one part first determines the cycle slip by the wide lane combination method and then eliminates the wild values ​​to obtain the wide lane ambiguity, and the other part first eliminates the wild values ​​by the geometry-free combination and then determines the cycle slip to obtain the wide lane ambiguity; Combine the wide lane ambiguities of the two parts, comprehensively calculate the cycle slip size of all cycle slips, then repair the cycle slips, and finally output the file; Step 3, process the abnormal values ​​of the new sequence of observation quantities used for navigation messages, generate standardized messages, and finally output the file. The schematic diagram of the steps is shown as follows Figure 3 shown.

[0021] Exemplarily, the Beidou observation data real-time quality control module includes a software initialization module, a data processing module and a data output module; in the software initialization module, the GNSS observation file directory is first selected to determine whether a necessary product is missing. If so, the necessary product is downloaded. If the download fails, the program is terminated. If the download is successful, BDS-B2b is initialized according to the configuration. If not, BDS-B2b is also initialized according to the configuration; then the observation file is read. If the observation file is read, the data output module is entered for processing. If the observation file is not read, the data processing module is entered for processing; after entering the data processing module, an epoch information is read and calculated. Calculate the corrections of various error models, and then calculate the approximate coordinates of the measuring station through SPP. Perform basic quality control on two adjacent epochs, and then perform filtering estimation to determine whether there are gross errors in the filtering. If so, remove the gross errors and re-perform filtering estimation. If no gross errors exist, retain the current epoch information and filtering estimation results, and re-read the observation file; after entering the data output module, solve the position file, each epoch model correction information and observation value residual file, and then terminate the program. The residual files include: ZTA, receiver type difference, ISB file, kml file, image drawing file and each satellite ambiguity file. The functional diagram of the Beidou observation data real-time quality control module is as follows Figure 4 shown.

[0022] For example, the static positioning error of GAMG is Figure 7 As shown, Figure 7 From top to bottom in the figure are four groups of static positioning NEU direction error sequences, namely B1I / B3I+GPS, B1C / B2a+GPS, B1I / B3I, and B1C / B2a. After the static PPP-B2b positioning of the GAMG station converges, the positioning errors of the four combinations fluctuate within plus or minus 0.05 meters. The plane positioning error is within 2 cm, which is better than the 4 cm positioning error in the elevation direction. The dual system has improved positioning accuracy compared with the single system.

[0023] For example, the kinematic positioning error of GAMG is Figure 8 As shown in the figure, the north, east, and up direction errors of the four combinations of dynamic PPP-B2b positioning at the GAMG station are: Figure 8From top to bottom in the figure, they are BDS B1I / B3I+GPS, BDS B1C / B2a +GPS, BDSB1I / B3I, and BDS B1C / B2a. After convergence, the errors in the north and east directions fluctuate within plus or minus 10 cm, and the RMS are 3 cm and 5 cm respectively. The elevation direction is poor, and the positioning errors of most epochs fluctuate within plus or minus 15 cm. Some epochs are close to 20 cm but do not exceed 20 cm. The RMS of the elevation direction B1C / B2a combination is the worst at 8 cm, and the other three combinations are 7 cm. The convergence time of the BDS single system is longer and the convergence accuracy is lower than that of the BDS+GPS dual system.

[0024] The above is only a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art shall not deviate from the spirit and scope of the present invention, and shall be within the scope of protection of the claims attached to the present invention.

Claims

1. A portable PPP-B2b Beidou positioning and timing device, characterized in that: include: GNSS receiver module, solution module and data solution accuracy assessment module; The GNSS receiver module includes a BDS / GNSS antenna and a high-precision BDS / GNSS positioning unit. The GNSS receiver module receives BDS / GNSS navigation satellite signals through the BDS / GNSS antenna, and performs capture, tracking, bit synchronization, frame synchronization and decoding processing through the high-precision BDS / GNSS positioning unit to obtain original navigation messages and obtain observation quantities at the measurement time. The observation quantities include pseudorange, carrier phase, and Doppler. The solution module includes a microcontroller, a serial communication unit, and a clock unit. The original navigation messages and observation quantities are output to the microcontroller in the form of real-time data streams. After receiving the data, the microcontroller organizes the data, processes the broadcast ephemeris and the broadcast SSR correction number, and generates real-time precise orbit data; the position and time are solved through the data solution accuracy evaluation module, the position information is sent out through the serial communication unit, and the clock difference sequence is predicted at the same time to obtain the steering quantity, which is used to control the frequency of the clock unit and the output of the second signal.

2. A portable PPP-B2b Beidou positioning and timing device according to claim 1, characterized in that: The data calculation accuracy assessment module performs the calculation of position and time including the following steps: S1, initialize, the original number , location covariance ; Calculate the receiver position of the initial position using SPP , Receiver clock error and fuzziness ; S2, original name When Then proceed to step S3, where is the positioning threshold; S3. Calculate the i Receiver clock error of BeiDou-3 satellites ,in For the i The wavelength of the BeiDou-3 satellites, For the i The coordinates of the BeiDou-3 satellites, For the i The phase observation values ​​of the BeiDou-3 satellites, For the i The error correction of the BeiDou III satellites and calculation of the first increment ,calculate the median of , where the first increment is i The third generation Beidou satellite and the i -The absolute value of the difference in receiver clock error of one BeiDou-3 satellite; S4. Calculate the second increment , if the second increment , then delete the kth satellite, where is the receiver deviation threshold, and the second increment is the absolute value of the difference between the first increment and the median of the first increment.

3. A portable PPP-B2b Beidou positioning and timing device according to claim 2, characterized in that: When using precision orbit and clock products The value is 5~10cm, It is used to detect cycle slips or gross errors of 1 or 0.5 cycles, with a value of 6~8cm.

4. A portable PPP-B2b Beidou positioning and timing device according to claim 1, characterized in that: It also includes a power supply module for converting the DC voltage to suit the different voltage requirements of each module.

5. A portable PPP-B2b Beidou positioning and timing device according to claim 1, characterized in that: Also includes: Beidou observation data real-time quality control module, used for data integrity analysis, data gross error processing, data cycle slip detection and receiver clock jump processing; Beidou real-time data processing module, used for various error analysis and processing, real-time dynamic solution model, ambiguity estimation and error model refinement; According to a portable PPP-B2b Beidou positioning and timing device according to claim 5, it is characterized in that the Beidou observation data real-time quality control module processes data including the following steps: Step 1: first input the real-time data stream, delete the bad data therein, and form a new sequence of observation quantities. If the real-time data stream initially input is all bad data, then delete all of them and input a new real-time data stream. The new sequence of observation quantities is divided into three parts, one part is directly output to a file, one part is used to set cycle slip detection parameters, and one part is used for navigation messages. Step 2: Divide the new sequence of observations used to set cycle slip detection parameters into two parts, one of which is to first determine the cycle slips through the wide lane combination method and then remove the outliers to obtain the wide lane ambiguity, and the other is to first remove the outliers through the geometry-free combination and then determine the cycle slips to obtain the wide lane ambiguity; combine the wide lane ambiguities of the two parts, comprehensively calculate the cycle slip size of all cycle slips, then repair the cycle slips, and finally output the file; Step 3: Process the abnormal values ​​of the new sequence of observation quantities for the navigation message, generate a standardized message, and finally output the message to a file.

6. A portable PPP-B2b Beidou positioning and timing device according to claim 5, characterized in that: The Beidou observation data real-time quality control module includes a software initialization module, a data processing module and a data output module; In the software initialization module, first select the GNSS observation file directory to determine whether the necessary products are missing. If they are missing, download the necessary products. If the download fails, terminate the program. If the download is successful, initialize BDS-B2b according to the configuration. If not missing, initialize BDS-B2b according to the configuration. Then read the observation file. If the observation file is read, enter the data output module for processing. If the observation file is not read, enter the data processing module for processing. After entering the data processing module, read an epoch information, calculate various error model corrections, and then calculate the approximate coordinates of the measuring station through SPP. Perform basic quality control on two adjacent epochs, and then perform filtering estimation to determine whether there is a gross error in the filtering. If so, remove the gross error and perform filtering estimation again. If no gross error exists, keep the current epoch information and filtering estimation results, and re-read the observation file. After entering the data output module, the position file, the model correction information of each epoch and the observation residual file are solved, and then the program is terminated. The residual files include: ZTA, receiver species difference, ISB file, kml file, drawing image file and ambiguity file of each satellite.

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