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CN112731465A - Method for supporting medium-and-long-distance pseudo-range differential positioning - Google Patents

Method for supporting medium-and-long-distance pseudo-range differential positioning Download PDF

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CN112731465A
CN112731465A CN202011433269.0A CN202011433269A CN112731465A CN 112731465 A CN112731465 A CN 112731465A CN 202011433269 A CN202011433269 A CN 202011433269A CN 112731465 A CN112731465 A CN 112731465A
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pseudo
range
ionosphere
free
frequency
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CN112731465B (en
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徐学永
周叶
夏羽
徐波
吴波
王琛琛
惠孟堂
汤深权
蒋虎
施金金
王伟
李哲
白天阳
张浩山
金俭俭
姜秋晨
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North Information Control Institute Group Co ltd
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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01SRADIO 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
    • G01S19/00Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
    • G01S19/01Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
    • G01S19/13Receivers
    • G01S19/24Acquisition or tracking or demodulation of signals transmitted by the system
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01SRADIO 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
    • G01S19/00Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
    • G01S19/01Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
    • G01S19/13Receivers
    • G01S19/24Acquisition or tracking or demodulation of signals transmitted by the system
    • G01S19/29Acquisition or tracking or demodulation of signals transmitted by the system carrier including Doppler, related
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01SRADIO 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
    • G01S19/00Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
    • G01S19/38Determining a navigation solution using signals transmitted by a satellite radio beacon positioning system
    • G01S19/39Determining 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
    • G01S19/40Correcting position, velocity or attitude
    • G01S19/41Differential correction, e.g. DGPS [differential GPS]
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01SRADIO 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
    • G01S19/00Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
    • G01S19/38Determining a navigation solution using signals transmitted by a satellite radio beacon positioning system
    • G01S19/39Determining 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
    • G01S19/42Determining position
    • G01S19/43Determining position using carrier phase measurements, e.g. kinematic positioning; using long or short baseline interferometry
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02ATECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A90/00Technologies having an indirect contribution to adaptation to climate change
    • Y02A90/10Information and communication technologies [ICT] supporting adaptation to climate change, e.g. for weather forecasting or climate simulation

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

Abstract

The invention discloses a method for supporting medium-and-long-distance pseudo-range differential positioning, which comprises the steps of constructing an ionosphere-free combination by using a dual-frequency GNSS signal when calculating a pseudo-range differential correction to eliminate an ionosphere delay error item, expanding the service range of the pseudo-range differential correction from 50km to 200km, smoothing the ionosphere-free combined pseudo-range observation value by using a carrier phase smoothing method, reducing the observation noise of the ionosphere-free combined pseudo-range observation value, generating a low-noise and high-precision differential correction, and facilitating medium-and-long-distance pseudo-range differential positioning.

Description

Method for supporting medium-and-long-distance pseudo-range differential positioning
Technical Field
The invention belongs to the satellite navigation positioning technology, and particularly relates to a method for supporting medium-long distance pseudo-range differential positioning.
Background
In satellite positioning, when performing single-point positioning using pseudo-range observation values, the real-time positioning accuracy is about 10 meters. The pseudo-range differential positioning technology is characterized in that one or more reference stations with known coordinates in a certain area are used for receiving the three-dimensional position of a satellite in real time, independently calculating the pseudo-range differential correction of the satellite, and then transmitting the pseudo-range differential correction to a rover station through data transmission chain broadcasting to perform pseudo-range differential positioning, so that the positioning accuracy of the rover station in a meter level or even a sub-meter level is realized. However, the conventional single-station pseudo range differential technology has short range, and the accuracy of positioning is rapidly reduced along with the increase of the range. Therefore, a technology supporting medium-long distance pseudo-range differential positioning is provided, so that the medium-long distance pseudo-range differential positioning technology can process a medium-long baseline of 50-200 km. In the calculation of pseudo-range differential correction, the non-ionosphere combination is utilized to eliminate an ionosphere delay error item by utilizing the dual-frequency GNSS signal composition, the service range of pseudo-range differential is expanded, meanwhile, the non-ionosphere pseudo-range observation value is subjected to smoothing treatment by adopting a low-noise inter-epoch carrier phase observation value, the observation noise of the non-ionosphere pseudo-range observation value is reduced, the low-noise and high-precision pseudo-range differential correction is generated, the original single-frequency differential data is replaced, the differential service range is expanded, and the effect that the original single-frequency transmission technology achieves dual-frequency positioning is achieved.
Disclosure of Invention
The invention aims to provide a method for supporting medium-and-long-distance pseudo range differential positioning, which solves the problem that the traditional pseudo range differential positioning method is seriously influenced by an ionized layer delay error when processing a medium-and-long baseline of 50 km-200 km.
The technical solution for realizing the purpose of the invention is a method for supporting medium-long distance pseudo-range differential positioning, which comprises the following steps:
step 1, erecting a double-frequency receiver on a reference point, wherein the double-frequency receiver is used for receiving a broadcast ephemeris, a double-frequency carrier phase and a double-frequency pseudo range;
step 2, calculating the three-dimensional position (X) of the satellite in the current epoch according to the satellite orbit parameters released by the broadcast ephemeris and by combining the three-dimensional coordinates of the reference stationS,YS,ZS) And the clock error deltat of the satellite, and calculating the geometric distance between the satellite and the reference station
Figure BDA0002827380360000011
Step 3, obtaining a dual-frequency pseudo range observed value P according to the dual-frequency pseudo range1And P2Using dual-frequency pseudorange observations P1And P2Constructing an ionosphere-free combination equation and generating an ionosphere-free combination pseudo-range observed value PIF
Step 4, obtaining a dual-frequency carrier phase observed value according to the dual-frequency carrier phase
Figure BDA0002827380360000021
And
Figure BDA0002827380360000022
using dual-frequency carrier phase observations
Figure BDA0002827380360000023
And
Figure BDA0002827380360000024
constructing a non-ionosphere combination equation to generate an observed value of a non-ionosphere combination carrier phase
Figure BDA0002827380360000025
Step 5, combining the observed values of the carrier phases by using the ionosphere-free layer
Figure BDA0002827380360000026
Combining pseudorange observations P for ionosphere-free layersIFPerforming phase smoothing to generate smoothed ionospheric-free pseudo-range observed value
Figure BDA0002827380360000027
Step 6, smoothing the non-ionospheric pseudo-range observed value
Figure BDA0002827380360000028
Incorporating geometric distance of satellite to reference station
Figure BDA0002827380360000029
Generating ionosphere-free pseudorange differential correction Δ PIF
Step 7, correcting value delta P of non-ionized layer pseudo rangeIFAnd broadcasting to provide medium and long distance low noise pseudo range differential service for users.
Compared with the prior art, the invention has the remarkable advantages that:
(1) the pseudo-range difference correction calculated by the invention eliminates the influence of an ionized layer, and the service range is expanded from 50km to 200 km.
(2) The carrier phase smoothing is carried out on the pseudo-range observed value without the ionized layer, so that the observation noise is greatly reduced, and the broadcasted differential correction is more stable and reliable.
Drawings
Fig. 1 is a flowchart illustrating a method for supporting medium-and-long-range pseudorange differential positioning according to the present invention.
Detailed Description
The present invention is described in further detail below with reference to the attached drawing figures.
With reference to fig. 1, a method for supporting medium-and-long-range pseudorange differential positioning includes the following steps:
step 1, erecting a double-frequency receiver on a reference point, wherein the double-frequency receiver is used for receiving a broadcast ephemeris, a double-frequency carrier phase and a double-frequency pseudo range;
step 2, calculating the three-dimensional position (X) of the satellite in the current epoch according to the satellite orbit parameters released by the broadcast ephemeris and by combining the three-dimensional coordinates of the reference stationS,YS,ZS) And the clock error deltat of the satellite, and calculating the geometric distance between the satellite and the reference station
Figure BDA0002827380360000031
Step 3, obtaining a dual-frequency pseudo range observed value P according to the dual-frequency pseudo range1And P2Using dual-frequency pseudorange observations P1And P2Constructing an ionosphere-free combination equation and generating an ionosphere-free combination pseudo-range observed value PIFAs shown in equation (1).
Figure BDA0002827380360000032
In the formula (f)1And f2The signal frequencies are the double-frequency observed values of the GNSS satellite; p1For a signal frequency f1Pseudo-range observation of (1), P2For a signal frequency f2Of the pseudo-range observations.
Step 4, obtaining a dual-frequency carrier phase observed value according to the dual-frequency carrier phase
Figure BDA0002827380360000033
And
Figure BDA0002827380360000034
using dual-frequency carrier phase observations
Figure BDA0002827380360000035
And
Figure BDA0002827380360000036
constructing a non-ionosphere combination equation to generate an observed value phi of the non-ionosphere combination carrier phaseIFAs shown in equation (2).
Figure BDA0002827380360000037
Wherein c is the speed of light,
Figure BDA0002827380360000038
for a signal frequency f1Is detected by the carrier-phase observation of (c),
Figure BDA0002827380360000039
for a signal frequency f2A carrier phase observation of (a). PIFAnd phiIFIonosphere error terms have been eliminated, but ionosphere-free combining also increases the observation noise.
Step 5, utilizing the ionosphere-free combined carrier phase observed value phiIFCombining pseudorange observations P for ionosphere-free layersIFPerforming phase smoothing to generate smoothed ionospheric-free pseudo-range observed value
Figure BDA00028273803600000310
The observation noise is reduced as shown in equation (3).
Figure BDA00028273803600000311
In the formula (I), the compound is shown in the specification,
Figure BDA00028273803600000312
and
Figure BDA00028273803600000313
are respectively shown at tiAnd ti-1Non-ionospheric pseudo-range observed value P after time smoothingIF(ti) Is shown at tiAn ionospheric-free pseudo-range observed value at a moment, i representing a smoothing number; delta phiIF(ti-1,ti) And representing the observed value change value without an ionosphere between epochs. Ionosphere-free pseudo-range observed value PIF(ti) After carrier phase smoothing, the observation noise is reduced.
Step 6, smoothing the non-ionospheric pseudo-range observed value
Figure BDA0002827380360000041
Incorporating geometric distance of satellite to reference station
Figure BDA0002827380360000042
Generating ionosphere-free pseudorange correction Δ PIFAs shown in formula (4).
Figure BDA0002827380360000043
In the formula (4), Δ PIF(ti) Is tiAn ionospheric-free pseudorange correction value for a time; at' is the receiver clock difference.
Step 7, correcting value delta P of non-ionized layer pseudo rangeIFAnd broadcasting to meet medium and long distance low noise pseudo range differential service.
In summary, compared with the traditional pseudo-range single-point positioning method, the pseudo-range differential correction method provided by the invention uses the reference station user to provide high-precision pseudo-range differential correction numbers, and because the correction numbers use double-frequency deionization layer combination and smooth the pseudo-range by using the carrier phase observation value, the user positioning is not affected by hardware delay, troposphere delay, ionosphere delay and satellite orbit error, so that the pseudo-range differential positioning is more accurate and the precision can reach a sub-meter level. In addition, the medium-and-long distance pseudo range differential positioning supporting technology provided by the invention has the advantages that the operation mode is flexible, the data volume played by the reference station to the user is small, the influence of an ionosphere on the positioning precision under the medium-and-long distance condition is effectively inhibited, and the positioning precision and stability of the user are improved.

Claims (5)

1. A method for supporting medium-and-long-range pseudo-range differential positioning is characterized by comprising the following steps:
step 1, erecting a double-frequency receiver on a reference point, wherein the double-frequency receiver is used for receiving a broadcast ephemeris, a double-frequency carrier phase and a double-frequency pseudo range;
step 2, calculating the three-dimensional position (X) of the satellite in the current epoch according to the satellite orbit parameters released by the broadcast ephemeris and by combining the three-dimensional coordinates of the reference stationS,YS,ZS) And the clock error deltat of the satellite, and calculating the geometric distance between the satellite and the reference station
Figure FDA00028273803500000111
Step 3, obtaining a dual-frequency pseudo range observed value P according to the dual-frequency pseudo range1And P2Using dual-frequency pseudorange observations P1And P2Constructing an ionosphere-free combination equation and generating an ionosphere-free combination pseudo-range observed value PIF
Step 4, obtaining a dual-frequency carrier phase observed value according to the dual-frequency carrier phase
Figure FDA0002827380350000011
And
Figure FDA0002827380350000012
using dual-frequency carrier phase observations
Figure FDA0002827380350000013
And
Figure FDA0002827380350000014
constructing a non-ionosphere combination equation to generate a non-ionosphere combination carrierPhase observation value
Figure FDA0002827380350000015
Step 5, combining the observed values of the carrier phases by using the ionosphere-free layer
Figure FDA0002827380350000016
Combining pseudorange observations P for ionosphere-free layersIFPerforming phase smoothing to generate smoothed ionospheric-free pseudo-range observed value
Figure FDA0002827380350000017
Step 6, smoothing the non-ionospheric pseudo-range observed value
Figure FDA0002827380350000018
Incorporating geometric distance of satellite to reference station
Figure FDA0002827380350000019
Generating ionosphere-free pseudorange differential correction Δ PIF
Step 7, correcting value delta P of non-ionized layer pseudo rangeIFAnd broadcasting to provide medium and long distance low noise pseudo range differential service for users.
2. The method for supporting medium-and-long range pseudorange differential positioning according to claim 1, wherein in step 3, ionosphere-free combined pseudorange observations PIFThe calculation formula is as follows:
Figure FDA00028273803500000110
in the formula (f)1And f2The signal frequencies are the double-frequency observed values of the GNSS satellite; p1For a signal frequency f1Pseudo-range observation of (1), P2For a signal frequency f2Of the pseudo-range observations.
3. The method of claim 1, wherein in step 4, ionosphere-free combined carrier-phase observations are made
Figure FDA0002827380350000021
The calculation formula is as follows:
Figure FDA0002827380350000022
wherein c is the speed of light,
Figure FDA0002827380350000023
for a signal frequency f1Is detected by the carrier-phase observation of (c),
Figure FDA0002827380350000024
for a signal frequency f2Of the carrier phase observation, PIFAnd
Figure FDA0002827380350000025
ionosphere error terms have been eliminated, but ionosphere-free combining also increases the observation noise.
4. The method of claim 1, wherein in step 5, the smoothed ionospheric-free pseudorange observations are smoothed
Figure FDA0002827380350000026
The calculation formula is as follows:
Figure FDA0002827380350000027
in the formula (I), the compound is shown in the specification,
Figure FDA0002827380350000028
and
Figure FDA0002827380350000029
are respectively shown at tiAnd ti-1Non-ionospheric pseudo-range observed value P after time smoothingIF(ti) Is shown at tiAn ionospheric-free pseudo-range observed value at a moment, i representing a smoothing number; delta phiIF(ti-1,ti) Representing the change value of the observed value of the carrier without an ionized layer between epochs; ionosphere-free pseudo-range observed value PIF(ti) After carrier phase smoothing, the observation noise is reduced.
5. The method of claim 1, wherein in step 6, ionospheric-free pseudorange differential corrections are Δ PIFThe calculation formula is as follows:
Figure FDA00028273803500000210
in the formula,. DELTA.PIF(ti) Is tiAn ionospheric-free pseudorange correction value for a time; at' is the receiver clock difference.
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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101295014A (en) * 2008-05-19 2008-10-29 中国测绘科学研究院 GNSS-based long-distance high-precision real-time/fast positioning method and system
CN104459737A (en) * 2014-12-02 2015-03-25 东南大学 Satellite positioning method based on real-time beacon differential
CN105044741A (en) * 2015-06-29 2015-11-11 中国科学院上海天文台 Solution method of pseudo range phase comprehensive wide-area differential correction value

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101295014A (en) * 2008-05-19 2008-10-29 中国测绘科学研究院 GNSS-based long-distance high-precision real-time/fast positioning method and system
CN104459737A (en) * 2014-12-02 2015-03-25 东南大学 Satellite positioning method based on real-time beacon differential
CN105044741A (en) * 2015-06-29 2015-11-11 中国科学院上海天文台 Solution method of pseudo range phase comprehensive wide-area differential correction value

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
YANRONG XUE 等: "Study of a New Pseudo-range Differential Method for the Correction of Ephemeris Error and Ionospheric Error", 《ADVANCED MEASUREMENT AND TEST III》 *
凌青 等: "相位平滑伪距差分技术在北斗定位中的应用探讨", 《交通科技与经济》 *
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