CN106959456B - A kind of GNSS SURVEYING CONTROL NETWORK Accuracy Estimation - Google Patents

A kind of GNSS SURVEYING CONTROL NETWORK Accuracy Estimation Download PDF

Info

Publication number
CN106959456B
CN106959456B CN201710187042.4A CN201710187042A CN106959456B CN 106959456 B CN106959456 B CN 106959456B CN 201710187042 A CN201710187042 A CN 201710187042A CN 106959456 B CN106959456 B CN 106959456B
Authority
CN
China
Prior art keywords
satellite
observation
precision
angle
accuracy
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201710187042.4A
Other languages
Chinese (zh)
Other versions
CN106959456A (en
Inventor
李祖锋
万宗礼
薛绍军
吕宝雄
缪志选
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
PowerChina Northwest Engineering Corp Ltd
Original Assignee
PowerChina Northwest Engineering Corp Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by PowerChina Northwest Engineering Corp Ltd filed Critical PowerChina Northwest Engineering Corp Ltd
Priority to CN201710187042.4A priority Critical patent/CN106959456B/en
Publication of CN106959456A publication Critical patent/CN106959456A/en
Application granted granted Critical
Publication of CN106959456B publication Critical patent/CN106959456B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • 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
    • G01S19/01—Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
    • G01S19/13—Receivers
    • G01S19/20—Integrity monitoring, fault detection or fault isolation of space segment
    • 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
    • G01S19/01—Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
    • G01S19/13—Receivers
    • G01S19/24—Acquisition or tracking or demodulation of signals transmitted by the system
    • G01S19/27—Acquisition or tracking or demodulation of signals transmitted by the system creating, predicting or correcting ephemeris or almanac data within the receiver

Landscapes

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

Abstract

The invention discloses a kind of GNSS SURVEYING CONTROL NETWORK Accuracy Estimations: 1, carrying out the analysis of baseline visible satellite based on satellite Ouluding boundary constraint condition, each survey station observation is simulated based on analysis result, it establishes double difference observation equation and solves, the baseline positioning precision factor is calculated according to the Q diagonal matrix in error equation；2, the simultaneous observation combined sorting of target observation point is carried out, count each baseline DOP value situation of different observation periods, and the estimation of ring accuracy of observation is synchronized according to the corresponding dilution of precision of network forming condition and observation period filtered out, the selection for simultaneous observation point and observation period；3, networking is carried out according to multiple synchronous rings, using the precision m of the variance matrix estimation algorithm estimation control net of basic lineal vectori.The present invention is suitable for carrying out GNSS observation in high-mountain gorge areas and the inferior observation area in hardship of city housing-group effect, and precision index is relatively reliable.

Description

GNSS measurement control network precision estimation method
Technical Field
The invention belongs to the technical field of GNSS measurement control network measurement, and particularly relates to a GNSS measurement control network precision estimation method.
Background
The most common method for estimating the accuracy of the current GNSS measurement control network is a simulation method, which needs to simulate observed quantity through the rough coordinates of control network points, simulate observed value covariance and select a suitable accuracy estimation model.
In addition, the accuracy that the GNSS measurement control network can achieve is influenced by the number of satellites that can be received in unit time, the distribution condition of the satellites, the duration of received satellite signals, and other factors, i.e., the accuracy of ephemeris forecast. Since the existing single-station accuracy factor calculation satellite visibility screening is generally set with a fixed altitude angle (e.g., 10 ° or 15 °), which is used as a judgment condition for satellite visibility, in practice, due to the fact that the satellite position is shielded from obstacles of a station, such as high mountain canyon areas and urban building group effect, there is a very large difference between actually-receivable satellite signals, and when the cutoff altitude angle E is 30 °, the time for seeing 4 or more GPS satellites accounts for 90% of the whole day, and when the cutoff altitude angle E is 40 °, the time for seeing 4 or more GPS satellites accounts for 47% of the whole day. In a high mountain canyon region, the shielding situation of a height angle larger than 30 degrees is often encountered, so that great errors exist in satellite visibility and accuracy factor prediction accuracy, the estimation of the measurement accuracy of the GNSS control network is influenced, and the auxiliary staff is not favorable for making a better observation scheduling plan.
Disclosure of Invention
The invention aims to provide a GNSS measurement control network accuracy estimation method, which solves the problem that the existing estimation method cannot take into account the actual satellite receiving condition of the control network and solves the problem that the existing estimation method does not take into account the shielding condition of a survey station, so that the accuracy estimation index is not in line with the actual condition.
The invention adopts a technical scheme that a GNSS measurement control network precision estimation method comprises the following steps:
step 1, estimating a baseline relative positioning precision factor RDOP value;
performing baseline shared satellite analysis based on satellite shielding boundary constraint conditions, simulating observation values of all stations based on analysis results, establishing a double-difference observation equation and an error equation, and solving; calculating a baseline relative positioning accuracy factor RDOP according to a Q diagonal matrix in an error equation, and decomposing a baseline vector accuracy factor into (DOP)ΔX,DOPΔY,DOPΔH) In the form of (a);
step 2, planning an observation scheme;
based on the calculated baseline relative positioning accuracy factor (DOP)ΔX,DOPΔY,DOPΔH) Synchronous observation combination screening of target observation points is carried out, DOP value conditions of all base lines in different observation periods are counted, and synchronous ring observation precision estimation is carried out according to screened networking conditions and precision factors corresponding to the observation periods and is used for selecting synchronous observation point positions and observation periods;
step 3, evaluating the accuracy of the control network according to a planning observation scheme;
and (3) networking according to the plurality of synchronous rings determined in the step (2), and performing precision estimation on the control network by adopting a variance matrix estimation algorithm of the baseline vector.
The invention is also characterized in that:
further, the establishing of the double-difference observation equation and the error equation and the solving in the step 1 are specifically implemented according to the following steps:
first, two endpoints of the baseline are defined as: starting point A (x)1,y1,z1)，B(x2,y2,z2) Knowing the coordinates (x) of point A1,y1,z1) And the observation equation is
Single station and single star
Then, double differential relative positioning is performed:
① single difference between stations
② differencing between satellites
Then, Q ═ A is obtainedTPA)-1I is the reference satellite and j is the other satellite;
further, in step 3, the accuracy m of the control network is estimated by using the variance matrix estimation method of the baseline vectoriThe method comprises a method for establishing a covariance matrix based on an estimated RDOP value and a precision estimation method based on the estimated covariance matrix, and specifically comprises the following steps: estimating the accuracy m of a control netiSubstituting the error delta into the unit weight0I.e. mi＝δR×δ0(ii) a Wherein delta0The calculation method comprises the following steps:
is singleCalculating the formula:
whereinFor actual resolution accuracy of baseline ij, RDOPijThe comprehensive relative precision factor corresponding to the baseline ij;
the control net delta0Comprises the following steps:
where n is the number of baselines used for statistics.
Further, in the step 1, the performing of the baseline common satellite analysis based on the satellite occlusion boundary constraint condition includes the following steps:
step 1, satellite visibility analysis;
(1) measuring the shielding height angle of the target point satellite;
under the coordinates of the center of the station, firstly determining the coordinates of a target point, then measuring cross section characteristic points from any direction by taking the target point as a center according to a certain angle to obtain a shielding height angle E corresponding to each direction of the target pointi；
(2) Resolving the satellite space position and converting coordinates;
a shielding height angle E according to step 1iAcquiring broadcast ephemeris information, then calculating the position of the satellite in a orbital plane coordinate system, and finally respectively acquiring the position of the satellite in an instantaneous spherical coordinate system and the position of the satellite in a protocol terrestrial spherical coordinate system through coordinate conversion;
(3) filtering obstacles to block the satellite;
converting the geocentric coordinates of the satellite calculated in the step (2) in a protocol terrestrial coordinate system into three-dimensional coordinates of a station center coordinate system with the ground survey station R as a coordinate origin, and further solving the altitude angle e and the azimuth angle A of the satellite; then, according to the altitude angle E and the azimuth angle A of the satellite at a certain azimuth at the designated time, and the shielding altitude angle E corresponding to each direction of the target point calculated in the step 1iObtaining the shielding height angle E of the position at the momenti(ii) a Then the satellite altitude e and the shielding altitude of the position at the moment are calculatedAngle EiMaking a comparison if E is less than or equal to EiIf the satellite is not visible, the satellite is rejected; if e>EiIf the satellite is visible, the satellite is reserved; according to the method, the satellites are filtered one by one to obtain accurate satellite visibility results;
step 2, calculating the DOP value of the geometric precision factor
And calculating the DOP value of the geometric accuracy factor based on the state matrix of the observation satellite group obtained by the method, thereby obtaining ephemeris forecast considering the satellite shielding condition.
Further, the shielding height angle E in the step (1)iThe calculation method comprises the following steps:
firstly, determining the coordinates of a target point, and then, clockwise measuring the cross section from any direction by taking the target point as a center according to a certain angle, wherein the measured cross section format is as follows: di,HiWherein D isiIs the plane distance from the feature point of the section to the target point, HiIs the elevation of the characteristic point of the section; secondly, calculating the elevation angle of the characteristic point according to the cross sectionSetting the target point to measure n altitude angles in total, and then setting the shielding altitude angle E corresponding to each direction of the target pointiComprises the following steps:
further, the elevation angle of the feature pointIs preferably calculated byIn the formula H0Is the target point elevation.
Further, the calculation method of the satellite altitude angle e and the satellite azimuth angle a in the step (3) comprises the following steps:
acquiring coordinates of a satellite in a station center coordinate system with a ground survey station R as a coordinate origin:
in the formula,
[XR YR ZR]Tthe WGS-84 coordinate vector of the ground station R is as follows:
where B and L are the geodetic latitude and the geodetic longitude, respectively, of the survey station R.
Then the satellite altitude e is:
the satellite azimuth A is:
wherein,
further, the occlusion of the specified time and orientation in step (3)Elevation angle EiThe calculation method comprises the following steps:
two adjacent occlusion height angles are known: (A)i-1，Ei-1)，(Ai+1，Ei+1) And solving the shielding height angle of the designated azimuth by linear interpolation: e ═ aA + b; will (A)i-1，Ei-1)，(Ai+1，Ei+1) Substituting the above formula to obtain parameters a and b; then the satellite azimuth A of the specified time is calculatediSubstituting the formula, solving the height shielding angle in the corresponding direction as: ei＝aAi+b。
Further, when the shielding condition is approximately linear change, the interpolation of the shielding altitude angle adopts i (the number of the shielding altitude angles is set to be n, i is less than or equal to n) point linear fitting to obtain the altitude angle of the undetermined point:
E＝a0+a1A+a2A2+...+anAn。
further, the calculation of the geometric precision factor DOP value in the step 2 adopts a direction cosine method; the geometric precision factor DOP value comprises a plane relative positioning precision factor HRDOP, an elevation precision factor VRDOP, a spatial position precision factor PRDOP, a comprehensive influence precision factor GDOP, a three-dimensional position precision factor PDOP, a horizontal component precision factor HDOP, a vertical component precision factor VDOP and a clock error precision factor TDOP value.
The invention has the beneficial effects that: (1) compared with the traditional method, the method has the advantages that the accuracy of the control network is estimated through the RDOP value, the shielding condition of each control point is considered in the accuracy estimation stage, and the relative positioning accuracy factor is determined through the simulation difference processing. (2) The method is suitable for GNSS observation in high mountain canyon regions, urban building group effect and other observation difficult regions, can estimate the precision index highly consistent with the actual satellite receiving condition, works out a more reliable observation scheme of the precision index according to the actual observation condition, assists in working out an observation scheduling plan with a more excellent precision index according to the equipment condition and the personnel condition, and evaluates the precision index of the control network according to the made observation plan. The method has unprecedented advantages for the establishment of the GNSS observation scheme under the environments of the high mountain canyons and the urban building areas.
Drawings
FIG. 1 is a flow chart illustrating a method for estimating the accuracy of a GNSS survey control network according to the present invention;
FIG. 2 is a schematic flow chart of satellite visibility analysis in ephemeris forecast with satellite occlusion conditions taken into account.
Detailed Description
The present invention will be described in further detail with reference to the drawings and the following detailed description, but the present invention is not limited to the following detailed description.
The method for estimating the accuracy of the GNSS measurement control network is implemented by referring to FIG. 1 according to the following steps:
step 1, satellite visibility analysis
A method for determining ephemeris forecast with consideration given to satellite occlusion conditions is shown in fig. 2.
(1) Measuring the shielding height angle of the target point satellite;
measurements of single-survey-station satellite elevation angles are made based on a topographical map, a Digital Elevation Model (DEM), or other digital geographic information products with elevation attributes.
Firstly, determining the coordinates of a target point, and then clockwise measuring the cross section (the cross section distance is determined according to the actual situation) from a north direction by taking the target point as a center according to a certain angle (5 degrees), wherein the measured cross section format is as follows:
Di,Hi
wherein DiIs the plane distance from the feature point of the section to the target point, HiFor the elevation of the characteristic point of the section, the eyes are setThe punctuation measures n elevation angles in total. Elevation angle of characteristic pointComprises the following steps:
H0for the elevation of the target point, the shielding elevation angle E corresponding to each direction of the target pointiComprises the following steps:
the GNSS elevation is generally expressed in the form of a standing center coordinate, and needs to be converted into the form of the standing center coordinate when the elevation measurement is performed by using a topographic map and DEM model data.
When the horizontal plane of the center-of-gravity coordinates is adopted to replace the level surface under the influence of the curvature of the earth, the calculation formula of the influence on the height difference is as follows:
when D is 2Km and 3Km, the effect on the height difference is 0.31m and 0.71 m. Therefore, the influence can be ignored in the general altitude measurement process, and the influence needs to be considered when higher requirements are met, and the altitude of the characteristic pointBecomes:
the altitude angle measured by a single measuring station is formatted as follows:
(2) resolving the satellite space position and converting coordinates;
and (2) downloading and analyzing the latest broadcast ephemeris information according to the target point shielding altitude measured in the step (1), wherein the broadcast ephemeris downloading and analysis are the basis of the GNSS ephemeris forecasting and precision evaluating module and are the precondition for satellite position calculation.
The position of the satellite in the orbital plane coordinate system is further calculated by calculating the average angular velocity of the satellite motion, the average point angle of the satellite at the observation moment, the deviation near point angle, the true near point angle, the lift angle distance and the perturbation correction item, and finally the position of the satellite in the instantaneous spherical coordinate system and the position of the satellite in the protocol spherical coordinate system are obtained by coordinate conversion.
(3) Filtering obstacles block satellites.
And analyzing and forecasting the satellite visibility number, the visibility and the DOP value of the single survey station according to the satellite almanac and the survey station satellite altitude angle file.
And (3) converting the geocentric coordinates of the satellite calculated in the step (2) in the protocol terrestrial coordinate system into three-dimensional coordinates of a station center coordinate system taking the ground survey station R as a coordinate origin, and further obtaining the altitude angle and the azimuth angle of the satellite, wherein the calculation methods of the altitude angle and the azimuth angle of the satellite of other systems are similar to the calculation methods. After the altitude angle and the azimuth angle of the satellite are obtained, the condition of the satellite visible at the target point position is obtained according to the shielding condition of the obstacle and the coordinate elevation information of the target point in the step 1, and the filtering of the satellite shielded by the obstacle can be realized by combining the shielding altitude angle information of the survey station measured in the step 1. The calculation process is as follows:
1) the calculation model of the satellite altitude and azimuth is as follows.
The coordinates of the satellite in the station center rectangular coordinate system are as follows:
in the formula,
[XR YR ZR]Tis the WGS-84 coordinate vector of the ground station R.
Where B and L are the geodetic latitude and the geodetic longitude, respectively, of the survey station R.
The satellite height angle is:
satellite azimuth:
2) screening of visible satellites
According to the altitude angle shielding information in the step 1, two adjacent shielding altitude angles are known as follows:
(Ai-1，Ei-1)，(Ai+1，Ei+1)
the occlusion height angle here is solved by linear interpolation:
E＝aA+b
will (A)i-1，Ei-1)，(Ai+1，Ei+1) The parameters a and b can be obtained by substituting the above equation. Satellite azimuth A of a given timeiSubstituting the formula, solving the height shielding angle in the corresponding direction as:
Ei＝aAi+b
comparing the altitude E and the shielding altitude E of the satelliteiJudging whether the satellite is visible or not, and judging the visible discriminant of the satellite:
e＞Ei
if E > EiIf the satellite is visible, the satellite is reserved; otherwise, the satellite is rejected.
For the shielding condition which is approximately linearly changed, the altitude angle interpolation can adopt i (the shielding altitude angle quantity is set to be n, i is less than or equal to n) point linear fitting to obtain the altitude angle of the undetermined point:
E＝a0+a1A+a2A2+...+anAn
therefore, satellite visibility is judged by filtering the conditions of the satellites blocked by the obstacles one by one.
And 2, calculating the DOP value of the geometric precision factor.
After a satellite visibility analysis result of an estimated satellite shielding condition is obtained, a direction cosine method is adopted to calculate a geometric precision factor DOP value by taking a state matrix of an observation satellite group obtained by the method as a basis, wherein the geometric precision factor DOP value comprises a plane relative positioning precision factor HRDOP, an elevation precision factor VRDOP, a spatial position precision factor PRDOP, a comprehensive influence precision factor GDOP, a three-dimensional position precision factor PDOP, a horizontal component precision factor HDOP, a vertical component precision factor VDOP and a clock error precision factor TDOP value. And then ephemeris forecast considering the satellite shielding condition is obtained. The control network precision estimation of the invention is carried out on the basis of the result, and the precision value estimated by the control network precision estimation is more in line with the actual situation.
In the above control network point location accuracy miFurther evaluating efficiency indexes such as theoretical design efficiency, actual design efficiency, total efficiency and the like of the control network on the basis of estimation; evaluating cost indexes by using the scale and the station repeated setting rate of the control network; evaluating redundant baselines by using the total number of the independent baselines and the necessary baselines of the control network, and calculating the reliability index of the whole network and the accuracy benefit index of the network type; and evaluating the precision condition of each point in the current technical design scheme and the precision information such as the side length precision, the azimuth angle precision, the redundant observation components and the like of each baseline, so that the information more conforming to the actual condition can be obtained.
The accuracy of the accuracy estimation of the control network can be improved through the steps, and the more accurate ephemeris forecast can be obtained only on the basis of satellite visibility analysis considering the satellite shielding condition, so that the more accurate control network accuracy value can be estimated.
Step 3, estimating a base line relative positioning precision factor RDOP value;
the estimation of the baseline relative positioning accuracy factor RDOP value can be regarded as the geometric distribution accuracy factor of the satellite, the baseline calculation is carried out, and the coordinate of another point is solved by utilizing a known coordinate to carry out relative positioning. Then in the error equation it is solved according to the relative positioning model. Its RDOP value is still the co-factor matrix of the error equation. And performing common satellite statistics of the base lines by calculating the difference of two end points of each base line formed by the control network.
Two endpoints of the baseline, starting point A (x)1,y1,z1)，B(x2,y2,z2)
①, knowing the coordinates (x) of point A1,y1,z1)
② equation of observation
Single station and single star
Double differential relative positioning
1) Single difference between measuring stations
2) Inter-satellite differencing
Simplifying:
Q＝(ATPA)-1(P may be an identity matrix).
i is the reference satellite and j is the other satellite.
It is known that point a may have a correlation coefficient of 0.
There are no observations, so the covariance matrix does not use L.
The relative positioning accuracy factor of base line RDOP can be determined according to the Q diagonal matrix, and the accuracy factor of base line vector is decomposed into (DOP)ΔX,DOPΔY,DOPΔH) In the form of (1).
And outputting the satellite visibility and RDOP values shared by the two base-line points according to the approximate coordinates of the arranged control network and the side length connection condition of the control network and the observation time interval plan.
Step 4, planning an observation scheme;
based on the calculated baseline relative positioning accuracy factor (DOP)ΔX,DOPΔY,DOPΔH) And carrying out synchronous observation combination screening on the target observation points, counting the DOP value conditions of each baseline in different observation periods, and carrying out synchronous ring observation precision estimation according to the screened network construction conditions and precision factors corresponding to the observation periods, wherein the synchronous observation combination screening is used for selecting synchronous observation point positions and observation periods.
The selection method of the synchronous observation point and the observation time interval comprises the following steps:
and supporting the overall accuracy statistics of the observation plan. After the observation plan is selected, statistical information such as visibility and DOP value of all baseline co-view satellites in a plurality of periods is given. And summarizing the precision information of different time periods and different baselines.
And setting and combining baselines according to the matching degree of the DOP values in the same time period, performing optimization evaluation on a plurality of schemes, giving an optimization scheme (comprising a synchronous observation sequence, time period starting and stopping time and baseline information), and appointing an observation plan according to the optimization scheme.
DOP (DOP) at target point of observation difficultydThe synchronous network construction recommendation establishes a virtual synchronous observation relation between the observation difficult point positions and n point positions capable of constructing the network, and forms DOP values of all base lines:
DOPd-1,DOPd-2,...,DOPd-i,...DOPd-n
and sequencing the DOP values in an ascending order, and sequentially intercepting R point positions as an optimal synchronous observation base line according to the number R of the instruments.
And determining the measurement control point of each synchronous observation time interval under manual intervention according to the precision analysis result and in combination with site terrain and traffic conditions.
Step 5, evaluating the accuracy of the control network according to a planning observation scheme;
and (3) networking according to the plurality of synchronous rings determined in the step (2) so as to carry out precision estimation of the control network. The precision evaluation method adopts a common variance array estimation algorithm of a baseline vector. Since the DOP value estimation provides a relative accuracy factor indicator, the point location accuracy indicator δ estimated based on thisRIs dimensionless relative accuracy, and in order to determine the accuracy of the control net, it is necessary to substitute an appropriate unit weight error delta in the covariance matrix0Wherein δ0The determination is generally performed according to the RDOP and the accuracy statistics under different observation environments. Is singleThe calculation formula is as follows:
whereinFor actual resolution accuracy of baseline ij, RDOPijIs the integrated relative precision factor corresponding to the baseline ij. The control net delta0Comprises the following steps:
in this formula n is the number of baselines used for statistics.
Therefore, the point position accuracy m of the control network can be determinediComprises the following steps:
mi＝δR×δ0
the steps comprise a method for establishing a variance (covariance) matrix based on the estimated RDOP value and a precision estimation method based on the estimated variance (covariance) matrix, and the precision of the control network can be estimated through the steps. The method is based on the estimated relative positioning accuracy factor, compared with the existing method, the method has the advantage that the accuracy estimation is closer to the real situation, and the method has obvious advantage in controlling the network distribution optimization in difficult areas.

Claims (9)

1. A GNSS measurement control network precision estimation method is characterized by comprising the following steps:
step 1, estimating a baseline relative positioning precision factor RDOP value;
performing baseline shared satellite analysis based on satellite shielding boundary constraint conditions, simulating observation values of all stations based on analysis results, establishing a double-difference observation equation and an error equation, and solving; calculating a baseline relative positioning accuracy factor RDOP according to a Q diagonal matrix in an error equation, and decomposing the baseline relative positioning accuracy factor into (DOP)ΔX,DOPΔY,DOPΔH) In the form of (a);
step 2, planning an observation scheme;
based on the calculated baseline relative positioning accuracy factor (DOP)ΔX,DOPΔY,DOPΔH) Synchronous observation combination screening of target observation points is carried out, DOP value conditions of all base lines in different observation periods are counted, and synchronous ring observation precision estimation is carried out according to screened networking conditions and precision factors corresponding to the observation periods and is used for selecting synchronous observation point positions and observation periods;
step 3, evaluating the accuracy of the control network according to a planning observation scheme;
networking according to the multiple synchronous rings determined in the step 2, and estimating the precision m of the control network by adopting a variance matrix estimation algorithm of a baseline vectori(ii) a The specific process is as follows:
estimating control network precision m by using variance matrix estimation method of baseline vectoriThe method comprises a method for establishing a covariance matrix based on an estimated RDOP value and a precision estimation method based on the estimated covariance matrix, and specifically comprises the following steps: estimating the accuracy m of a control netiSubstituting the error delta into the unit weight0I.e. mi＝RDOPij×δ0(ii) a Wherein delta0The calculation method comprises the following steps:
is singleCalculating the formula:
whereinFor actual resolution accuracy of baseline ij, RDOPijThe comprehensive relative precision factor corresponding to the baseline ij;
the control net delta0Comprises the following steps:
where n is the number of baselines used for statistics.
2. The method for estimating the accuracy of the GNSS measurement control network according to claim 1, wherein the step 1 of establishing the double-difference observation equation and the error equation and solving comprises the following steps:
first, two endpoints of the baseline are defined as: starting point A (x)1,y1,z1)，B(x2,y2,z2) Knowing the coordinates (x) of point A1,y1,z1) And the observation equation is single station and single star
Then, double differential relative positioning is performed:
① single difference between stations
② differencing between satellites
Then, Q ═ A is obtainedTPA)-1I is the reference satellite and j is the other satellite;
3. the method of claim 1, wherein the step 1 of performing baseline common satellite analysis based on the constraint condition of the satellite occlusion boundary further comprises the steps of:
step 1.1, satellite visibility analysis;
(1) measuring the shielding height angle of the target point satellite;
under the coordinates of the center of the station, firstly determining the coordinates of a target point, then measuring cross section characteristic points from any direction by taking the target point as a center according to a certain angle to obtain a shielding height angle E corresponding to each direction of the target pointi；
(2) Resolving the satellite space position and converting coordinates;
a shielding height angle E according to step (1)iAcquiring broadcast ephemeris information, then calculating the position of the satellite in a orbital plane coordinate system, and finally respectively acquiring the position of the satellite in an instantaneous spherical coordinate system and the position of the satellite in a protocol terrestrial spherical coordinate system through coordinate conversion;
(3) filtering obstacles to block the satellite;
converting the geocentric coordinates of the satellite calculated in the step (2) in a protocol terrestrial coordinate system into three-dimensional coordinates of a station center coordinate system with the ground survey station R as a coordinate origin, and further solving the altitude angle e and the azimuth angle A of the satellite; then, according to the altitude angle E and the azimuth angle A of the satellite at a certain azimuth at the designated time, and the shielding altitude angle E corresponding to each direction of the target point calculated in the step 1iObtaining the shielding height angle E of the position at the momenti(ii) a Then the satellite altitude E and the shielding altitude E of the azimuth at the moment are calculatediMaking a comparison if E is less than or equal to EiIf the satellite is not visible, the satellite is rejected; if E > EiIf the satellite is visible, the satellite is reserved; according to the method, the satellites are filtered one by one to obtain accurate satellite visibility results;
step 1.2, calculating the DOP value of the geometric precision factor
And calculating the DOP value of the geometric accuracy factor based on the state matrix of the observation satellite group obtained by the method, thereby obtaining ephemeris forecast considering the satellite shielding condition.
4. The GNSS measurement control network accuracy estimation method of claim 3, wherein the shielding height E in step (1) isiThe calculation method comprises the following steps:
first the coordinates of the target point are determined and then the target point is determinedThe cross section is measured clockwise from any direction by a certain angle by taking the punctuation as the center, and the measured cross section format is as follows: di,HiWherein D isiIs the plane distance from the feature point of the section to the target point, HiIs the elevation of the characteristic point of the section; secondly, calculating the elevation angle of the characteristic point according to the cross sectionSetting the target point to measure n altitude angles in total, and then setting the shielding altitude angle E corresponding to each direction of the target pointiComprises the following steps:
5. the GNSS measurement control network accuracy estimation method of claim 4, wherein the elevation angle of the feature point isIs calculated by the formulaIn the formula H0Is the target point elevation.
6. The accuracy estimation method of GNSS measurement control network according to claim 3, wherein the calculation method of the satellite elevation e and azimuth A in step (3) is:
acquiring coordinates of a satellite in a station center coordinate system with a ground survey station R as a coordinate origin:
in the formula,
[XR YR ZR]Tthe WGS-84 coordinate vector of the ground station R is as follows:
wherein B and L are respectively the geodetic latitude and the geodetic longitude of the survey station R;
then the satellite altitude e is:
the satellite azimuth A is:
wherein,
7. the GNSS measurement control network accuracy estimation method of claim 3, wherein the occlusion height E at the specified time and orientation in step (3) isiThe calculation method comprises the following steps:
two adjacent occlusion height angles are known: (A)i-1，Ei-1)，(Ai+1，Ei+1) And solving the shielding height angle of the designated azimuth by linear interpolation: e ═ aA + b; will be provided withSubstituting the above formula to obtain parameters a and b; then the satellite azimuth A of the specified time is calculatediSubstituting the formula, solving the height shielding angle in the corresponding direction as: ei＝aAi+b。
8. The accuracy estimation method for the GNSS measurement control network according to claim 7, wherein when the occlusion condition is approximately linear change, the occlusion altitude angle interpolation adopts i point linear fitting to obtain the altitude angle of the undetermined position:
E＝a0+a1A+a2A2+...+anAn
in the formula, n is the number of the shielding height angles, and i is less than or equal to n.
9. The GNSS measurement control network accuracy estimation method according to claim 3, characterized in that the calculation of the geometric dilution of precision DOP value in step 1.2 is by direction cosine method; the geometric precision factor DOP value comprises a plane relative positioning precision factor HRDOP, an elevation precision factor VRDOP, a spatial position precision factor PRDOP, a comprehensive influence precision factor GDOP, a three-dimensional position precision factor PDOP, a horizontal component precision factor HDOP, a vertical component precision factor VDOP and a clock error precision factor TDOP value.
CN201710187042.4A 2017-03-27 2017-03-27 A kind of GNSS SURVEYING CONTROL NETWORK Accuracy Estimation Active CN106959456B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201710187042.4A CN106959456B (en) 2017-03-27 2017-03-27 A kind of GNSS SURVEYING CONTROL NETWORK Accuracy Estimation

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201710187042.4A CN106959456B (en) 2017-03-27 2017-03-27 A kind of GNSS SURVEYING CONTROL NETWORK Accuracy Estimation

Publications (2)

Publication Number Publication Date
CN106959456A CN106959456A (en) 2017-07-18
CN106959456B true CN106959456B (en) 2019-04-26

Family

ID=59471505

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201710187042.4A Active CN106959456B (en) 2017-03-27 2017-03-27 A kind of GNSS SURVEYING CONTROL NETWORK Accuracy Estimation

Country Status (1)

Country Link
CN (1) CN106959456B (en)

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107505631B (en) * 2017-07-19 2021-03-02 广东省交通规划设计研究院股份有限公司 Double-reference-station type GNSS control network measurement method
CN111221005B (en) * 2018-11-27 2022-06-28 千寻位置网络有限公司 Positioning accuracy calculation method and device based on position information
CN109459765B (en) * 2018-12-12 2020-09-01 中铁二局集团有限公司 High-precision tunnel independent control network establishment method based on existing GNSS control network
CN111505687B (en) * 2020-04-17 2021-12-21 中国科学院国家授时中心 Original observation value gross error rejection method based on GPS satellite navigation system
CN112729175B (en) * 2020-12-04 2022-09-30 中国电建集团河北省电力勘测设计研究院有限公司 Small-area control measurement operation method for power plant and power station
CN113960646B (en) * 2021-11-02 2024-05-10 中国电子科技集团公司第二十八研究所 Double-station photoelectric multi-target elevation matching positioning method
CN115015969A (en) * 2022-06-02 2022-09-06 长安大学 GNSS satellite visibility forecasting method under mountain area sheltering environment
CN115267830B (en) * 2022-09-27 2022-12-30 中国电建集团西北勘测设计研究院有限公司 GNSS emergency monitoring error suppression method for complex environment of high mountain canyon
CN117055074B (en) * 2023-10-13 2024-01-23 中国电子科技集团公司第十五研究所 Relative precision comprehensive quantitative evaluation method, server and storage medium

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6646604B2 (en) * 1999-01-08 2003-11-11 Trueposition, Inc. Automatic synchronous tuning of narrowband receivers of a wireless location system for voice/traffic channel tracking
US6505122B1 (en) * 2001-06-25 2003-01-07 Qualcomm, Incorporated Method and apparatus for providing accurate position estimates in instances of severe dilution of precision
EP1500907B1 (en) * 2003-07-21 2014-11-12 LG Electronics, Inc. Apparatus and method for detecting vehicle location in navigation system
CN103399326B (en) * 2013-08-20 2015-04-15 武汉大学 GNSS (global navigation satellite system) dynamic measurement accuracy test system and method
CN104598746A (en) * 2015-01-27 2015-05-06 国家测绘地理信息局大地测量数据处理中心 Applicability discrimination method for coordinate transformation model
CN106526629B (en) * 2016-12-23 2019-01-22 广州海格通信集团股份有限公司 Satellite navigation and its orientation method and device
CN106683126B (en) * 2017-01-16 2019-12-03 重庆大学 A kind of method of target distributed mass in quantitative assessment point cloud registering

Also Published As

Publication number Publication date
CN106959456A (en) 2017-07-18

Similar Documents

Publication Publication Date Title
CN106959456B (en) A kind of GNSS SURVEYING CONTROL NETWORK Accuracy Estimation
CN106970398B (en) Satellite visibility analysis and ephemeris forecasting method considering satellite shielding condition
CN102506824B (en) Method for generating digital orthophoto map (DOM) by urban low altitude unmanned aerial vehicle
CN111123300B (en) Near-real-time large-range high-precision ionosphere electron density three-dimensional monitoring method and device
CN108332649A (en) A kind of landslide deformation comprehensive pre-warning method and system
CN102998690B (en) Attitude angle direct resolving method based on global position system (GPS) carrier wave double-difference equation
JP6328917B2 (en) Method and system for determining errors in estimating the time required to traverse the ionosphere
Xu Application of GPS-RTK technology in the land change survey
CN107976702A (en) A kind of position correcting method based on CORS, positioning terminal and alignment system
CN114019584A (en) VRS resolving method for high-precision CORS network in large-altitude-difference area
CN112859130B (en) High-precision electronic map position matching method for field navigation patrol
CN109917494A (en) Rainfall forecast method, apparatus, equipment and storage medium
CN110261876A (en) The unrelated GNSS of high precision position monitors virtual reference method
KR100510835B1 (en) Method for constituting geographic information system applied digital map using real time measuring systems
CN108253942A (en) A kind of method for improving oblique photograph and measuring empty three mass
CN107860357B (en) Normal altitude measurement method, system, server and cloud platform
CN111830536A (en) Satellite visibility judgment method combined with terrain influence
CN111722250A (en) Common-mode error extraction method for earth crust deformation image based on GNSS time sequence
KR100448054B1 (en) Method for Preparing Geographical Information System Employing the Amended Value as Road Data
Al-Hameedawi et al. Updating cadastral maps using GIS techniques
Taylor et al. Surface modelling for GPS satellite visibility
Noinak et al. Testing Horizontal Coordinate Correction Model Used for Transformation from PPP GNSS Technique to Thai GNSS CORS Network Based on ITRF2014
Alves et al. Introduction of a geometry-based network RTK quality indicator
Ferrara et al. Adaptation of the Global Geoid Model EGM2008 on Campania Region (Italy) based on geodetic network points
Alhamadani et al. GNSS positioning techniques for enhancing Google Earth data quality

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant