CN111831965B

CN111831965B - Integrity monitoring method and device for UPD correction in SSR

Info

Publication number: CN111831965B
Application number: CN201910330167.7A
Authority: CN
Inventors: 赵启龙; 郭海林; 冯彦同
Original assignee: Qianxun Spatial Intelligence Inc
Current assignee: Qianxun Spatial Intelligence Inc
Priority date: 2019-04-23
Filing date: 2019-04-23
Publication date: 2023-09-12
Anticipated expiration: 2039-04-23
Also published as: CN111831965A

Abstract

The application relates to the field of positioning, and discloses an integrity monitoring method and device for UPD correction in SSR. The method comprises the following steps: calculating PPP and PPP-AR in real time for a plurality of integrity monitoring stations to obtain phase residual errors of the PPP and PPP-AR, obtaining phase residual errors of UPD change parts, and calculating the average value mu thereof _x And standard deviation delta _x Mean mu _x And standard deviation delta _x Substitution: pl=μ _x +K _int δ _x +Flow，K _int The PL is short for UPD protection level, and the Flow is a constant value. PL and alarm threshold comparison, if greater than alarm threshold, integrity indicator is marked as "unavailable"; if less than the alarm threshold, the integrity flag is marked as "available". The integrity monitoring of the UPD correction is realized, so that the broadcasted UPD correction contains an integrity mark, and the integrity mark is broadcasted to a user.

Description

Integrity monitoring method and device for UPD correction in SSR

Technical Field

The application relates to the field of positioning, in particular to an integrity monitoring technology for UPD correction in SSR.

Background

The existing PPP (Precise Point Positioning, precise single-point positioning) precision and reliability are both plagued by the fact that the ambiguity is difficult to fix into an integer, and because the UPD (Uncalibrated Phase Delay ) at the satellite end or the receiver end cannot be completely eliminated by adopting a non-difference or inter-satellite difference technology, the ambiguity is difficult to maintain the whole-cycle characteristic, the convergence time is long, and the requirement of quick positioning service is difficult to meet. The PPP-AR (precise single point positioning after fixed ambiguity) is just to solve this problem, and the PPP-AR algorithm can implement PPP with fixed ambiguity by using UPD correction. However, no method for monitoring the integrity of the UPD correction exists at present, and the integrity of the UPD correction cannot be monitored.

Therefore, there is a need for an integrity monitoring method for UPD correction, which improves the integrity monitoring technology, so that the integrity of the UPD correction can be monitored, and the integrity mark after being determined is broadcasted to the user.

Disclosure of Invention

The application aims to provide an integrity monitoring method and device for UPD (UPD) correction in SSR, which realize integrity monitoring of the UPD correction, enable the broadcasted UPD correction to contain an integrity mark and broadcast the integrity mark to a user.

In order to solve the technical problems, the embodiment of the application discloses an integrity monitoring method of UPD correction in SSR, which comprises the following steps:

obtaining observation values of a plurality of integrity monitoring stations, and obtaining a track clock correction and a UPD correction in the SSR correction;

calculating PPP and PPP-AR for the plurality of integrity monitoring stations in real time by using the observed value, the track clock correction and the UPD correction to obtain phase residual errors of the PPP and the PPP-AR;

calculating the difference value of the phase residual errors of the PPP and the PPP-AR to obtain the phase residual error of the UPD change part;

calculating a mean μ of phase residuals of UPD varying portions of the plurality of integrity monitoring stations _x And standard deviation delta _x And the average value mu _x And standard deviation delta _x Substitution:

PL＝μ _x +K _int δ _x +Flow

wherein PL is UPD protection level, K _int The number of quantiles of standard normal distribution corresponding to the phase residual error of the UPD change part is constant;

and comparing the PL with a preset alarm threshold, and outputting the integrity mark of the UPD correction.

The embodiment of the application also discloses an integrity monitoring device for the UPD correction in the SSR, which comprises the following components:

the acquisition unit is used for acquiring the observation values of the plurality of integrity monitoring stations and acquiring the track clock correction and the UPD correction in the SSR correction;

the first calculation unit is used for calculating PPP and PPP-AR in real time for the plurality of integrity monitoring stations by using the observed value, the track clock correction and the UPD correction to obtain phase residual errors of the PPP and the PPP-AR;

a second calculating unit, configured to calculate a difference value between the phase residuals of the PPP and the PPP-AR, to obtain a phase residual of the UPD changing part;

a third calculation unit for calculating the average mu of the phase residuals of UPD variation parts of the plurality of integrity monitoring stations _x And standard deviation delta _x And the average value mu _x And standard deviation delta _x Substitution:

PL＝μ _x +K _int δ _x +Flow

and the comparison output unit is used for comparing the PL with a preset alarm threshold and outputting the integrity mark of the UPD correction.

The embodiment of the application also discloses an integrity monitoring device for UPD correction in SSR, comprising:

a memory for storing computer executable instructions; the method comprises the steps of,

a processor for implementing the steps of the above method when executing the computer executable instructions.

The embodiment of the application also discloses a computer-readable storage medium, wherein the computer-readable storage medium stores computer-executable instructions, and the computer-executable instructions realize the steps in the method when being executed by a processor.

Compared with the prior art, the embodiment of the application has the main differences and effects that:

and the integrity monitoring of the UPD correction is realized, so that the broadcasted UPD correction contains an integrity mark, and the integrity mark is broadcasted to the user.

When the PPP and PPP-AR are calculated in real time by the plurality of integrity monitoring stations, a series of model correction and clock-skip repair can be performed, and cycle-skip and gross error detection are added in the calculation process, so that the calculation result is more accurate.

The numerous technical features described in the description of the present application are distributed among the various technical solutions, which can make the description too lengthy if all possible combinations of technical features of the present application (i.e., technical solutions) are to be listed. In order to avoid this problem, the technical features disclosed in the above summary of the application, the technical features disclosed in the following embodiments and examples, and the technical features disclosed in the drawings may be freely combined with each other to constitute various new technical solutions (these technical solutions are regarded as already described in the present specification) unless such a combination of technical features is technically impossible. For example, in one example, feature a+b+c is disclosed, in another example, feature a+b+d+e is disclosed, and features C and D are equivalent technical means that perform the same function, technically only by alternative use, and may not be adopted simultaneously, feature E may be technically combined with feature C, and then the solution of a+b+c+d should not be considered as already described because of technical impossibility, and the solution of a+b+c+e should be considered as already described.

Drawings

FIG. 1 is a flow chart of a method for integrity monitoring of UPD correction in SSR according to a first embodiment of the present application;

fig. 2 is a flow chart of a preferred embodiment according to the first embodiment of the present application;

FIG. 3 is a schematic diagram of the structure of a UPD correction integrity monitoring device in SSR in accordance with a second embodiment of the application.

Detailed Description

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, it will be understood by those skilled in the art that the claimed application may be practiced without these specific details and with various changes and modifications from the embodiments that follow.

For the purpose of making the objects, technical solutions and advantages of the present application more apparent, embodiments of the present application will be described in further detail below with reference to the accompanying drawings.

First, each term used in the present application will be explained:

UPD: uncalibrated Phase Delay, the phase delay is not calibrated.

PPP: precise Point Positioning, precise single-point positioning, is a method for performing high-precision single-point positioning by using high-precision satellite ephemeris and satellite clock errors provided by organizations such as carrier phase observations and IGS (International GPS Service ).

PPP-AR: and (3) a precise single-point positioning algorithm after the ambiguity is fixed.

PPP-RTK: PPP-RTK is used as a new technology, which combines the technical advantages of PPP and NRTK, and can obtain the ambiguity fixing solution in a short time, thereby realizing the real-time centimeter-level positioning accuracy of the user.

RTK is Real Time Kinematic, and the real-time dynamic positioning is performed.

NRTK: network Real Time Kinematic, network real-time dynamic positioning.

SSR: state Space Representation the state space description, mainly providing GNSS error source information, is distinguished from OSR information used by differential GNSS and NRTK (Observation Space Representation, observed value state space), mainly comprises: satellite orbit error, satellite clock bias, satellite signal bias, ionospheric delay parameters, tropospheric delay parameters, quality indicators of state parameters, such as URA (user range accuracy). For different mobile station scenes, the space state information can be converted into observed value space information, so that the positioning precision of the mobile station is improved, and different SSR messages provide different precision levels. In particular for real-time PPP applications, SSR information is essential, and the current RTCM3.2 document defines SSR information (orbit, clock skew and satellite hardware bias) sufficient to support dual-system real-time PPP: DF-RT-PPP, after the definition of real-time atmospheric delay information and satellite phase deviation information, the real-time PPP and RTK-PPP of a single system can be realized.

And (3) GNSS: global Navigation Satellite System, global navigation satellite system.

RTCM: radio Technical Commission for Maritime services, radio technical Commission of International maritime Commission.

Integrity: is the ability to direct the navigation system to alert the user in time when it is unavailable for navigation services.

Protection stage (PL): when the integrity enhancement system is applied, a limit deviation value needs to be obtained conservatively through various models and known parameters and is reflected to a final positioning domain called a Protection Level.

Cycle skip: the ambiguity jumps throughout the cycle.

Rough differences: refers to observations that are greater than 3 times the error.

The first embodiment of the application relates to an integrity monitoring method for UPD correction in SSR. FIG. 1 is a flow chart of a method for integrity monitoring of UPD correction in the SSR.

Specifically, as shown in fig. 1, the integrity monitoring method for the UPD correction in the SSR comprises the following steps:

in step 101, observations of a plurality of integrity monitoring stations are obtained, and track clock correction and UPD correction in the SSR correction are obtained.

In the embodiments of the present application, the integrity monitoring station: refers to a static observation station dedicated to integrity monitoring.

An observation, comprising: pseudo-range observations and phase observations, etc.

The orbit clock correction refers to the correction broadcast in the SSR for correcting satellite orbits and clock errors.

In other certain embodiments of the application, the track clock correction may also include its integrity information.

Thereafter, step 102 is entered, wherein the PPP and PPP-AR are calculated in real time for the plurality of integrity monitoring stations using the observed values, the track clock correction and the UPD correction, and phase residuals of the PPP and PPP-AR are obtained.

And calculating phase residuals of the PPP and the PPP-AR by using the parameter estimation values of the PPP and the PPP-AR, namely substituting the observation values and the correction into an observation equation.

It should be noted that, the calculation of the phase residuals of PPP and PPP-AR belongs to the prior art, and is not the protection focus of the present application, and is not further developed here.

Further, preferably, when the plurality of integrity monitoring stations calculate PPP and PPP-AR in real time, a series of model corrections and clock-skip repairs can be performed, and cycle-skip and gross error detection are added in the calculation process, so that the calculation result can be more accurate.

Thereafter, step 103 is performed to calculate the difference between the phase residuals of the PPP and PPP-AR, so as to obtain the phase residual of the UPD variation part.

Thereafter, step 104 is entered, where the average μ of the phase residuals of the UPD varying portions of the plurality of integrity monitoring stations is calculated _x And standard deviation delta _x (every time of every star) and comparing the mean value mu _x And standard deviation delta _x Substitution:

PL＝μ _x +K _int δ _x +Flow

PL is a UPD protection level (also called UPD limit deviation); k (K) _int The quantiles (namely percentile points) of the standard normal distribution corresponding to the phase residual error of the UPD change part; the Flow is a constant and needs to be set according to the actual test result.

Thereafter, step 105 is entered, wherein the PL is compared to a predetermined alarm threshold and an integrity indicator of the UPD correction is output.

The flow is ended thereafter.

Further, preferably, in step 105, the following sub-steps are included:

if the PL is greater than or equal to the alarm threshold, the integrity is identified as "unavailable";

if the PL is less than the alarm threshold, the integrity is identified as "available".

In this embodiment, the alarm threshold is preferably 0.3cm. Of course, this is a preferred embodiment, and in some other embodiments, the alarm threshold may be other values, not limited thereto.

Still further, preferably, after step 105, the following steps may be further included:

and adding the message of the integrity mark into a message of a UPD correction in the SSR.

In summary, the integrity monitoring method for the UPD correction in the SSR disclosed by the application can realize the integrity monitoring of the UPD correction, so that the broadcasted UPD correction contains an integrity mark and the integrity mark is broadcasted to a user.

A preferred embodiment of the present application will be described in detail below. Fig. 2 is a flow chart of the preferred embodiment.

As shown in fig. 2, the integrity monitoring method of UPD correction in SSR shown in the preferred embodiment is divided into three processes: preprocessing, calculation and comparison and broadcasting.

The pretreatment process comprises the following steps: accessing the observation value of the integrity monitoring station, accessing the clock error track correction, and reading the UPD correction in the SSR correction. According to the observed value and the correction, the existing software is utilized by a plurality of monitoring stations to calculate PPP and PPP-AR in real time so as to extract the phase residual error of the UPD change part (namely, calculate the difference value of the phase residual error obtained by PPP and PPP-AR), a plurality of columns of model correction and clock jump repair are suggested to be carried out in the existing software, and cycle jump and gross error detection are suggested to be added in the calculation process.

The calculation and comparison process is as follows: the positioning error is obtained by the difference between the estimated station coordinates of the same observation station and the reference coordinates. The phase residuals are calculated using the estimates of PPP and PPP-AR and the observation equation. Counting the difference between the phase residuals of PPP and PPP-AR, i.e. the phase residual of UPD variation part, calculating the average mu of the phase residual differences of multiple stations _x And standard deviation delta _x (every time of day, the mean and standard deviation are taken in:

PL＝μ _x +K _int δ _x +Flow

K _int the quantiles of the standard normal distribution corresponding to the phase residual difference value are the percentile points; PL is a UPD protection level; the Flow is a constant value and needs to be set according to the actual test result. PL and alarm threshold (alarm threshold may be set to 0.3 cm) are compared and if greater than the alarm threshold, the integrity indicator is marked as "unavailable"; if less than the alarm threshold, the integrity is identified as "available".

The broadcasting process is as follows: and adding the telegrams with the integrity monitoring marks into the SSR telegrams, so that the UPD correction numbers of each group of SSRs are provided with the integrity marks.

The integrity monitoring method of the UPD correction in the SSR improves the integrity monitoring technology, so that the UPD correction can be monitored for integrity, and the judged integrity mark is broadcasted to a user.

The method embodiments of the present application may be implemented in software, hardware, firmware, etc. Regardless of whether the application is implemented in software, hardware, or firmware, the instruction code may be stored in any type of computer accessible memory (e.g., permanent or modifiable, volatile or non-volatile, solid or non-solid, fixed or removable media, etc.). Also, the Memory may be, for example, programmable array logic (Programmable Array Logic, abbreviated as "PAL"), random access Memory (Random Access Memory, abbreviated as "RAM"), programmable Read-Only Memory (Programmable Read Only Memory, abbreviated as "PROM"), read-Only Memory (ROM), electrically erasable programmable Read-Only Memory (Electrically Erasable Programmable ROM, abbreviated as "EEPROM"), magnetic disk, optical disk, digital versatile disk (Digital Versatile Disc, abbreviated as "DVD"), and the like.

The second embodiment of the application relates to an integrity monitoring device for UPD correction in SSR. FIG. 3 is a schematic diagram of the structure of the UPD correction integrity monitoring device in the SSR.

Specifically, as shown in fig. 3, the integrity monitoring device for UPD correction in the SSR includes:

and the acquisition unit is used for acquiring the observation values of the plurality of integrity monitoring stations and acquiring the track clock correction and the UPD correction in the SSR correction.

And the first calculation unit is used for calculating PPP and PPP-AR for the plurality of integrity monitoring stations in real time by using the observed value, the track clock correction and the UPD correction to obtain phase residual errors of the PPP and the PPP-AR.

Further, preferably, the first computing unit is further configured to: model correction and clock-skip repair are performed and cycle-skip and gross error detection are added during the computation.

And the second calculation unit is used for calculating the difference value of the phase residual errors of the PPP and the PPP-AR to obtain the phase residual error of the UPD change part.

PL＝μ _x +K _int δ _x +Flow

Further, preferably, the comparison output unit compares the PL with a predetermined alarm threshold:

outputting the integrity flag as "unavailable" if the PL is greater than or equal to the alarm threshold;

if the PL is less than the alarm threshold, the integrity flag is output as "available".

Still further, preferably, the integrity monitoring device for UPD correction in the SSR further includes:

and the adding unit is used for adding the message of the integrity mark into the message of the UPD correction in the SSR.

To sum up, the integrity monitoring device for UPD correction in the SSR disclosed by the application performs simultaneous calculation of two sets of filters by using PPP and PPP-AR to obtain the phase residual of the UPD variation part, and calculates the average mu of the phase residual differences of a plurality of monitoring stations _x And standard deviation delta _x (every time of every star), the mean μ is calculated _x And standard deviation delta _x Substitution:

PL＝μ _x +K _int δ _x +Flow

wherein K is _int The PL is short for UPD protection level, and the Flow is a constant value. PL and alarm threshold comparison, if greater than alarm threshold, integrity indicator is marked as "unavailable"; if less than the alarm threshold, the integrity flag is marked as "available". The integrity monitoring of the UPD correction is realized, so that the broadcasted UPD correction contains an integrity mark, and the integrity mark is broadcasted to a user.

The present embodiment is an apparatus embodiment corresponding to the first embodiment, and can be implemented in cooperation with the first embodiment. The related technical details mentioned in the first embodiment are still valid in this embodiment, and in order to reduce repetition, a detailed description is omitted here. Accordingly, the related art details mentioned in the present embodiment can also be applied to the first embodiment.

It should be noted that, as will be understood by those skilled in the art, the implementation functions of the unit modules shown in the embodiments of the above-described device for monitoring the integrity of the UPD correction in the SSR can be understood with reference to the description of the above-described method for monitoring the integrity of the UPD correction in the SSR. The functions of each unit module shown in the implementation of the UPD correction integrity monitoring device in the SSR may be implemented by a program (executable instructions) running on a processor, or may be implemented by specific logic circuits. The integrity monitoring device for UPD correction in the SSR according to the embodiments of the present specification may also be stored in a computer readable storage medium if implemented in the form of a software functional module and sold or used as a stand-alone product. Based on such understanding, the technical solutions of the embodiments of the present specification may be embodied in essence or a part contributing to the prior art in the form of a software product stored in a storage medium, including several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the methods described in the embodiments of the present specification. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read Only Memory (ROM), a magnetic disk, an optical disk, or other various media capable of storing program codes. Thus, embodiments of the present specification are not limited to any specific combination of hardware and software.

Accordingly, the present description also provides a computer-readable storage medium having stored therein computer-executable instructions which, when executed by a processor, implement the method embodiments of the present description. Computer-readable storage media, including both non-transitory and non-transitory, removable and non-removable media, may implement information storage by any method or technology. The information may be computer readable instructions, data structures, modules of a program, or other data. Examples of storage media for a computer 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 disc read only memory (CD-ROM), digital Versatile Discs (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices, or any other non-transmission medium, which can be used to store information that can be accessed by a computing device. Computer-readable storage media, as defined herein, does not include transitory computer-readable media (transmission media), such as modulated data signals and carrier waves.

In addition, the embodiment of the specification also provides an integrity monitoring device for UPD correction in SSR, which comprises a memory for storing computer executable instructions, and a processor; the processor is configured to implement the steps of the method embodiments described above when executing computer-executable instructions in the memory. The processor may be a central processing unit (Central Processing Unit, abbreviated as "CPU"), other general purpose processors, digital signal processors (Digital Signal Processor, abbreviated as "DSP"), application specific integrated circuits (Appl ication Specific Integrated Circuit, abbreviated as "ASIC"), and the like. The aforementioned memory may be a read-only memory (ROM), a random access memory (random access memory, RAM), a Flash memory (Flash), a hard disk, a solid state disk, or the like. The steps of the method disclosed in the embodiments of the present application may be directly embodied in a hardware processor for execution, or may be executed by a combination of hardware and software modules in the processor.

It should be noted that in the present patent application, relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element. In the present patent application, if it is mentioned that an action is performed according to an element, it means that the action is performed at least according to the element, and two cases are included: the act is performed solely on the basis of the element and is performed on the basis of the element and other elements. Multiple, etc. expressions include 2, 2 times, 2, and 2 or more, 2 or more times, 2 or more.

All references mentioned in this disclosure are to be considered as being included in the disclosure of the application in its entirety so that modifications may be made as necessary. Further, it is understood that various changes or modifications of the present application may be made by those skilled in the art after reading the above disclosure, and such equivalents are intended to fall within the scope of the application as claimed.

Claims

1. The integrity monitoring method of the UPD correction in the SSR is characterized by comprising the following steps of;

calculating PPP and PPP-AR for the plurality of integrity monitoring stations in real time by using the observed value, the track clock correction and the UPD correction to obtain a PPP phase residual error and a PPP-AR phase residual error;

calculating the difference value between the phase residual error of the PPP and the phase residual error of the PPP-AR to obtain the phase residual error of the UPD change part;

PL＝μ _x +K _int δ _x +Flow

2. The method for integrity monitoring of UPD correction in SSR of claim 1, wherein in said step of calculating PPP and PPP-AR for said plurality of integrity monitoring stations in real time, the sub-steps of:

model correction and clock-skip repair are performed and cycle-skip and gross error detection are added during the computation.

3. The method of integrity monitoring of UPD corrections in SSR of claim 1, characterized in that in said step of comparing said PL with a predetermined alarm threshold and outputting an integrity indicator of said UPD corrections, it comprises the sub-steps of:

4. The method for integrity monitoring of UPD correction in SSR of claim 1, wherein the alarm threshold is 0.3cm.

5. A method of integrity monitoring of UPD corrections in SSR according to any of claims 1 to 4, characterized in that after said step of comparing said PL with a predetermined alarm threshold and outputting an integrity indicator of said UPD correction, it further comprises the steps of:

6. An integrity monitoring device for UPD correction in SSR, comprising:

the first calculation unit is used for calculating PPP and PPP-AR in real time for the plurality of integrity monitoring stations by using the observed value, the track clock correction and the UPD correction to obtain a PPP phase residual error and a PPP-AR phase residual error;

a second calculating unit, configured to calculate a difference between the phase residual error of the PPP and the phase residual error of the PPP-AR, to obtain a phase residual error of the UPD changing part;

PL＝μ _x +K _int δ _x +Flow

7. The device for integrity monitoring of UPD correction in SSR of claim 6, wherein the first computing unit is further configured to: model correction and clock-skip repair are performed and cycle-skip and gross error detection are added during the computation.

8. An integrity monitoring device of UPD correction in SSR as in claim 6 wherein said comparison output unit compares said PL to a predetermined alarm threshold,

9. An integrity monitoring device for UPD correction in SSR according to claim 6, characterized in that said alarm threshold is 0.3cm.

10. An integrity monitoring device of UPD correction in SSR according to any one of claims 6 to 9, further comprising:

11. An integrity monitoring device for UPD correction in SSR, comprising:

a processor for implementing the steps in the method of any one of claims 1 to 5 when executing the computer executable instructions.

12. A computer readable storage medium having stored therein computer executable instructions which when executed by a processor implement the steps in the method of any one of claims 1 to 5.