CN112946710A - Network RTK enhanced positioning method and device - Google Patents

Network RTK enhanced positioning method and device Download PDF

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Publication number
CN112946710A
CN112946710A CN202110287152.4A CN202110287152A CN112946710A CN 112946710 A CN112946710 A CN 112946710A CN 202110287152 A CN202110287152 A CN 202110287152A CN 112946710 A CN112946710 A CN 112946710A
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reference station
network rtk
data processing
mobile
processing center
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胡明贤
许超钤
王鑫哲
张良
孔建
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Wuhan Xingchen Beidou Technology Co ltd
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Wuhan Xingchen Beidou Technology Co ltd
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S19/00—Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
    • G01S19/38—Determining a navigation solution using signals transmitted by a satellite radio beacon positioning system
    • G01S19/39—Determining a navigation solution using signals transmitted by a satellite radio beacon positioning system the satellite radio beacon positioning system transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
    • G01S19/42—Determining position
    • G01S19/45—Determining position by combining measurements of signals from the satellite radio beacon positioning system with a supplementary measurement
    • G01S19/46—Determining position by combining measurements of signals from the satellite radio beacon positioning system with a supplementary measurement the supplementary measurement being of a radio-wave signal type

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  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Computer Networks & Wireless Communication (AREA)
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  • General Physics & Mathematics (AREA)
  • Position Fixing By Use Of Radio Waves (AREA)

Abstract

The invention discloses a network RTK enhanced positioning method, which comprises the following steps: s01, detecting ionospheric activity indexes and GNSS reference station coordinate changes; s02, temporarily erecting a mobile reference station at the center position of the area with the ionospheric activity index exceeding the threshold value A; s03, building a flow reference station near the GNSS reference station or in a field operation area, wherein the coordinate change of the GNSS reference station is larger than a threshold B; s04, calling a data processing module of the mobile reference station, and resolving the whole-cycle ambiguity of the mobile reference station through ionosphere interpolation values generated by the system and precision information of the ionosphere interpolation values; s05, calculating the accurate ionospheric delay of the mobile reference station, and correcting the network RTK correction information; and S06, broadcasting network RTK correction information. The problem that in the prior art, the positioning accuracy is poor, the reliability is low, the usability is limited in an area with active ionospheric activity, and the real-time positioning of a positioning user in an area near an original reference station is affected when the original reference station is damaged is solved.

Description

Network RTK enhanced positioning method and device
Technical Field
The invention relates to the technical field of network RTK, in particular to a network RTK enhanced positioning method and device.
Background
In RTK positioning, distance-related errors including ionospheric delay, tropospheric delay are the main cause of limiting the effective working distance of RTK positioning in the double-difference mode. The network RTK technology carries out regional modeling on errors, and the limitation of distance-related errors on RTK positioning distance is greatly weakened, so that the positioning distance of a user is increased to tens of kilometers of the network RTK technology from within 10-15km of the traditional single-station RTK technology. However, because the ionospheric activity is abnormally active in a part of low latitude areas in China, the influence of ionospheric delay on positioning cannot be effectively weakened by the original network RTK technology, and thus the original network RTK system cannot provide stable and reliable positioning service for a user under the condition that the ionospheric activity is abnormal. In addition, in practical application of network RTK, the reference station may not be normally used due to power failure, receiver failure, network interruption, geological disaster, position change, and the like, so that the distance between the network RTK base station is suddenly increased, thereby affecting the positioning service of the network RTK system to the positioning user near the base station. Therefore, the existing network RTK has the following problems:
1) the positioning precision is poor, the reliability is low and the availability is limited in an ionized layer active area;
2) the damage of the original reference station will affect the real-time positioning of the positioning users in the area near the station.
Disclosure of Invention
In order to solve the defects and shortcomings of the prior art, the invention aims to provide a network RTK enhanced positioning method and a network RTK enhanced positioning device.
The technical scheme of the invention is as follows: a network RTK enhanced positioning method, the method comprising:
s01, detecting the ionospheric activity index and the GNSS reference station coordinate change, executing the step S02 if the ionospheric activity index exceeds a threshold A, and executing the step S03 if the GNSS reference station coordinate change is greater than a threshold B;
s02, temporarily erecting a mobile reference station at the center position of the area with the ionospheric activity index exceeding the threshold A, detecting whether the real-time data of the mobile reference station is received by the network RTK data processing center, and executing the step S04 if the real-time data of the mobile reference station is received;
s03, building a mobile reference station near the GNSS reference station or in a field working area, wherein the coordinate change of the GNSS reference station is larger than a threshold B, detecting whether real-time data of the mobile reference station are received by a network RTK data processing center, and executing the step S04 if the real-time data of the mobile reference station are received;
s04, calling a data processing module of the mobile reference station, and resolving the whole-cycle ambiguity of the mobile reference station through an ionosphere interpolation value generated by the system and the precision information of the ionosphere interpolation value;
s05, calculating the accurate ionospheric delay of the mobile reference station, and correcting the network RTK correction information;
and S06, broadcasting network RTK correction information.
Further, the flow reference station integer ambiguity is resolved by the following equation:
Figure BDA0002980930500000021
Figure BDA0002980930500000022
Figure BDA0002980930500000023
Figure BDA0002980930500000024
Figure BDA0002980930500000025
in the formula (I), the compound is shown in the specification,
Figure BDA0002980930500000026
the tropospheric delay correction received by the user,
Figure BDA0002980930500000027
the ionospheric delay correction number received for the user,
Figure BDA0002980930500000028
for the parameter to be estimated to be the baseline vector,
Figure BDA0002980930500000029
is the L1 flow reference station integer ambiguity,
Figure BDA00029809305000000210
is the L2 flow reference station integer ambiguity,
Figure BDA00029809305000000211
is the L1 ionospheric delay,
Figure BDA00029809305000000212
for the L1 double-difference carrier observations,
Figure BDA00029809305000000213
is the L2 double difference carrier observation, epsilon is the observation noise,
Figure BDA00029809305000000214
for the L1 double-differenced pseudorange observations,
Figure BDA00029809305000000215
for L2 double-differenced pseudorange observations, λ1At L1 carrier wavelength, λ2Is the carrier wavelength of L2, f1Is L1 carrier frequency, f2Is the L2 carrier frequency.
Further, the accurate ionospheric delay of the mobile reference station is calculated by the following formula:
Figure BDA00029809305000000216
in the formula, λ1At L1 carrier wavelength, λ2Is the carrier wavelength of L2, f1Is L1 carrier frequency, f2Is the L2 carrier frequency, phi1Is the L1 carrier observation, phi2Is an L2 carrier observation, N1For L1 flow reference station full cycle ambiguity, N2Is the L2 flow reference station integer ambiguity,
Figure BDA00029809305000000217
representing the double difference between the satellites and ionospheric delay, Iono.
A network RTK enhanced positioning apparatus, comprising:
a first mobile reference station electrically connected to the network RTK data processing center, the first mobile reference station disposed at a GNSS reference station of the network RTK.
Further, still include:
the system comprises a space environment monitoring module, a network RTK data processing center and a data processing module, wherein the space environment monitoring module is electrically connected with the network RTK data processing center;
and the second flow reference station is electrically connected with the network RTK data processing center and is arranged in the center of the fault area.
Further, the first streaming reference station is connected to a network RTK data processing center via a TCP/IP protocol.
Further, the second flow reference station is connected to a network RTK data processing center via a TCP/IP protocol.
Further, the transmission message formats of the first streaming reference station and the network RTK data processing center are RCTM3.2 and higher.
Further, the transmission message formats of the second flow reference station and the network RTK data processing center are RCTM3.2 and higher.
The invention has the beneficial effects that: compared with the prior art, the method judges the ionospheric activity abnormal area and the GNSS reference station fault area by monitoring the ionospheric activity index and the GNSS reference station coordinate change, uses the mobile reference station to temporarily encrypt the GNSS reference station network in the fault area under the condition of not giving out the accurate coordinate of the mobile reference station, shortens the distance between the GNSS reference stations, obtains the atmosphere delay correction information of the area, and further ensures the accuracy and the reliability of the network RTK positioning service.
Drawings
FIG. 1 is a flow chart of example 1 of the present invention;
fig. 2 is a block diagram of an embodiment 2 of the present invention.
Detailed Description
The invention will be further described with reference to the following drawings and specific embodiments:
example 1 was carried out: referring to fig. 1, a network RTK enhanced positioning method, the method comprising:
s01, detecting the ionospheric activity index and the GNSS reference station coordinate change, executing the step S02 if the ionospheric activity index exceeds a threshold A, and executing the step S03 if the GNSS reference station coordinate change is greater than a threshold B;
s02, temporarily erecting a mobile reference station at the center position of the area with the ionospheric activity index exceeding the threshold A, detecting whether the real-time data of the mobile reference station is received by the network RTK data processing center, and executing the step S04 if the real-time data of the mobile reference station is received; the threshold value a here can be determined through experiments, subject to the accuracy satisfaction and the reliability satisfaction of the network RTK positioning service.
S03, building a mobile reference station near the GNSS reference station or in a field working area, wherein the coordinate change of the GNSS reference station is larger than a threshold B, detecting whether real-time data of the mobile reference station are received by a network RTK data processing center, and executing the step S04 if the real-time data of the mobile reference station are received; the threshold B can be determined through experiments, subject to the accuracy and reliability of the network RTK positioning service.
S04, calling a data processing module of the mobile reference station, and resolving the whole-cycle ambiguity of the mobile reference station through an ionosphere interpolation value generated by the system and the precision information of the ionosphere interpolation value;
s05, calculating the accurate ionospheric delay of the mobile reference station, and correcting the network RTK correction information;
and S06, broadcasting network RTK correction information.
The ionospheric activity abnormal area and the GNSS reference station fault area are judged by monitoring ionospheric activity index and GNSS reference station coordinate change, and under the condition that the accurate coordinate of the mobile reference station is not required to be given, the mobile reference station is used for temporarily encrypting a GNSS reference station network in the fault area, so that the distance between the GNSS reference stations is shortened, the atmosphere delay correction information of the area is obtained, and the accuracy and the reliability of network RTK positioning service are further ensured.
Further, the flow reference station integer ambiguity is resolved by the following equation:
Figure BDA0002980930500000041
Figure BDA0002980930500000042
Figure BDA0002980930500000043
Figure BDA0002980930500000044
Figure BDA0002980930500000045
in the formula (I), the compound is shown in the specification,
Figure BDA0002980930500000046
the tropospheric delay correction received by the user,
Figure BDA0002980930500000047
the ionospheric delay correction number received for the user,
Figure BDA0002980930500000048
for the parameter to be estimated to be the baseline vector,
Figure BDA0002980930500000049
is the L1 flow reference station integer ambiguity,
Figure BDA00029809305000000410
is the L2 flow reference station integer ambiguity,
Figure BDA00029809305000000411
is the L1 ionospheric delay,
Figure BDA00029809305000000412
for the L1 double-difference carrier observations,
Figure BDA00029809305000000413
is the L2 double difference carrier observation, epsilon is the observation noise,
Figure BDA00029809305000000414
for the L1 double-differenced pseudorange observations,
Figure BDA00029809305000000415
for L2 double-differenced pseudorange observations, λ1At L1 carrier wavelength, λ2Is the carrier wavelength of L2, f1Is L1 carrier frequency, f2Is the L2 carrier frequency.
And resolving the whole-cycle ambiguity of the mobile reference station, namely calculating the accurate ionosphere information of the mobile reference station on the premise of not needing accurate coordinates, and further correcting the original atmospheric correction information.
Further, the accurate ionospheric delay of the mobile reference station is calculated by the following formula:
Figure BDA0002980930500000051
in the formula, λ1At L1 carrier wavelength, λ2Is the carrier wavelength of L2, f1Is L1 carrier frequency, f2Is the L2 carrier frequency, phi1Is the L1 carrier observation, phi2Is an L2 carrier observation, N1For L1 flow reference station full cycle ambiguity, N2Is the L2 flow reference station integer ambiguity,
Figure BDA0002980930500000052
representing the double difference between the satellites and ionospheric delay, Iono.
Ionospheric correction information is calculated from the mobile reference station integer ambiguity.
Example 2 was carried out: referring to fig. 2, a network RTK enhanced positioning apparatus includes: a first rover station 3, said first rover station 3 being electrically connected to the network RTK data processing center 2, the first rover station 3 being disposed at a GNSS reference station of the network RTK.
The network RTK data processing center 2 monitors the coordinate change of the GNSS reference station to judge the fault of the GNSS reference station, and under the condition that the accurate coordinate of the mobile reference station is not required to be given, the network RTK data processing center 2 temporarily encrypts the GNSS reference station network in a fault area by using the mobile reference station, shortens the distance between the GNSS reference stations, obtains atmosphere delay correction information of the area, and further ensures the accuracy and reliability of network RTK positioning service.
Further, still include: the system comprises a space environment monitoring module 1, a network RTK data processing center 2 and a data processing module, wherein the space environment monitoring module 1 is electrically connected with the network RTK data processing center 2; a second flow reference station 4, the second flow reference station 4 being electrically connected to the network RTK data processing center 2, the second flow reference station 4 being disposed at the fault area center.
The ionosphere activity index is monitored by the space environment monitoring module 1 to judge an ionosphere activity abnormal area, and under the condition that the accurate coordinate of the mobile reference station is not required to be given, the mobile reference station is used for temporarily encrypting a GNSS reference station network in a fault area, so that the distance between the GNSS reference stations is shortened, the atmosphere delay correction information of the area is obtained, and the accuracy and the reliability of the network RTK positioning service are further ensured.
Further, the first flow reference station 3 is connected to the network RTK data processing center 2 through a TCP/IP protocol.
The optical fiber, 5G or 4G can be used for communicating with the network RTK through the existing internet, and cost is saved.
Further, the second flow reference station 4 is connected to the network RTK data processing center 2 through a TCP/IP protocol.
The optical fiber, 5G or 4G can be used for communicating with the network RTK through the existing internet, and cost is saved.
Further, the transmission message formats of the first flow reference station 3 and the network RTK data processing center 2 are RCTM3.2 and higher.
With RCTM3.2 and higher versions of the teletext format, data decoding is faster and more secure.
Further, the transmission message formats of the second flow reference station 4 and the network RTK data processing center 2 are RCTM3.2 and higher.
With RCTM3.2 and higher versions of the teletext format, data decoding is faster and more secure.
The foregoing is a more detailed description of the invention in connection with specific preferred embodiments and it is not intended that the invention be limited to these specific details. For those skilled in the art to which the invention pertains, several simple deductions or substitutions can be made without departing from the spirit of the invention, and all shall be considered as belonging to the protection scope of the invention.

Claims (9)

1. A network RTK enhanced positioning method, the method comprising:
s01, detecting the ionospheric activity index and the GNSS reference station coordinate change, executing the step S02 if the ionospheric activity index exceeds a threshold A, and executing the step S03 if the GNSS reference station coordinate change is greater than a threshold B;
s02, temporarily erecting a mobile reference station at the center position of the area with the ionospheric activity index exceeding the threshold A, detecting whether the real-time data of the mobile reference station is received by the network RTK data processing center, and executing the step S04 if the real-time data of the mobile reference station is received;
s03, building a mobile reference station near the GNSS reference station or in a field working area, wherein the coordinate change of the GNSS reference station is larger than a threshold B, detecting whether real-time data of the mobile reference station are received by a network RTK data processing center, and executing the step S04 if the real-time data of the mobile reference station are received;
s04, calling a data processing module of the mobile reference station, and resolving the whole-cycle ambiguity of the mobile reference station through ionosphere interpolation values generated by the system and precision information of the ionosphere interpolation values;
s05, calculating the accurate ionospheric delay of the mobile reference station, and correcting the network RTK correction information;
and S06, broadcasting network RTK correction information.
2. The network RTK enhanced positioning method of claim 1, wherein the rover station integer ambiguity is resolved by the following equation:
Figure FDA0002980930490000011
Figure FDA0002980930490000012
Figure FDA0002980930490000013
Figure FDA0002980930490000014
Figure FDA0002980930490000015
in the formula (I), the compound is shown in the specification,
Figure FDA0002980930490000016
the tropospheric delay correction received by the user,
Figure FDA0002980930490000017
for the ionospheric delay correction number received by the user,
Figure FDA0002980930490000018
for the parameter baseline vector to be estimated,
Figure FDA0002980930490000019
is the L1 flow reference station integer ambiguity,
Figure FDA00029809304900000110
is the L2 flow reference station integer ambiguity,
Figure FDA00029809304900000111
is the L1 ionospheric delay,
Figure FDA00029809304900000112
for the L1 double-difference carrier observations,
Figure FDA00029809304900000113
is the L2 double difference carrier observation, epsilon is the observation noise,
Figure FDA00029809304900000114
for the L1 double-differenced pseudorange observations,
Figure FDA00029809304900000115
for L2 double-differenced pseudorange observations, λ1At L1 carrier wavelength, λ2Is the carrier wavelength of L2, f1Is L1 carrier frequency, f2Is the L2 carrier frequency.
3. The network RTK enhanced positioning method of claim 1, wherein the precise ionospheric delay of the rover station is calculated by the formula:
Figure FDA0002980930490000021
in the formula, λ1At L1 carrier wavelength, λ2Is the carrier wavelength of L2, f1Is L1 carrier frequency, f2Is the L2 carrier frequency, phi1Is the L1 carrier observation, phi2Is an L2 carrier observation, N1Flows for L1Integer ambiguity of reference station, N2Is the L2 flow reference station integer ambiguity,
Figure FDA0002980930490000022
representing the double difference between the satellites and ionospheric delay, Iono.
4. A network RTK enhanced positioning apparatus, comprising:
a network RTK data processing center (2);
a first mobile reference station (3), said first mobile reference station (3) being electrically connected to the network RTK data processing center (2), the first mobile reference station (3) being provided at a GNSS reference station of the network RTK.
5. The network RTK enhanced positioning apparatus of claim 4, further comprising:
the system comprises a space environment monitoring module (1), a network RTK data processing center (2) and a data processing module, wherein the space environment monitoring module (1) is electrically connected with the network RTK data processing center (2);
and the second flow reference station (4), the second flow reference station (4) is electrically connected with the network RTK data processing center (2), and the second flow reference station (4) is arranged in the center of the fault area.
6. The network RTK enhanced positioning apparatus according to claim 4, characterized in that the first streaming reference station (3) is connected to the network RTK data processing center (2) via TCP/IP protocol.
7. The network RTK enhanced positioning device according to claim 5, characterized in that the second streaming reference station (4) is connected to the network RTK data processing center (2) via TCP/IP protocol.
8. The network RTK enhanced positioning apparatus of claim 6, characterized in that the transmitted text format of the first streaming reference station (3) and the network RTK data processing center (2) is RCTM3.2 and higher.
9. The network RTK enhanced positioning apparatus according to claim 7, wherein the transmission text format of the second flow reference station (4) and the network RTK data processing center (2) is RCTM3.2 and higher.
CN202110287152.4A 2021-03-18 2021-03-18 Network RTK enhanced positioning method and device Pending CN112946710A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113819863A (en) * 2021-10-08 2021-12-21 中国科学院国家授时中心 Deformation monitoring method and system
CN115616625A (en) * 2022-10-08 2023-01-17 国家基础地理信息中心 GNSS real-time data migration method and system
CN117420571A (en) * 2023-12-19 2024-01-19 武汉大学 Far coast static and dynamic reference station networking positioning method and system based on floating platform

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113819863A (en) * 2021-10-08 2021-12-21 中国科学院国家授时中心 Deformation monitoring method and system
CN115616625A (en) * 2022-10-08 2023-01-17 国家基础地理信息中心 GNSS real-time data migration method and system
CN117420571A (en) * 2023-12-19 2024-01-19 武汉大学 Far coast static and dynamic reference station networking positioning method and system based on floating platform
CN117420571B (en) * 2023-12-19 2024-03-19 武汉大学 Far coast static and dynamic reference station networking positioning method and system based on floating platform

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