阅读说明：本技术 利用gnss浮标的验潮站垂直基准检测方法 (Vertical reference detection method for tide station by utilizing GNSS buoy ) 是由 杨磊 于 2020-12-21 设计创作，主要内容包括：本发明涉及一种利用GNSS浮标的验潮站垂直基准检测方法,属于验潮站垂直基准检测技术领域。本发明包括如下步骤：S1：GNSS精密水准的测量、S2：GNSS浮标的现场布放、S3：GNSS静态参考站的架设、S4：GNSS观测时间的设定、S5：GNSS浮标SSH的计算、S6：潮汐信号SSH的数据滤波、S7：SSH大地水准面差异的消除、S8：GNSS和验潮站垂直基准的统一。本发明利用高精度GNSS测高浮标通过观测WGS-84参考椭球基准下的海面高度信息,避免上述三个问题,方便、经济的布设在海洋站附近海域,避免验潮站基准位移误差和水准测量误差积累,在任意海域(包括)远海岛礁区域进行验潮站基准统一。(The invention relates to a vertical reference detection method for a tide station by utilizing a GNSS buoy, belonging to the technical field of vertical reference detection of tide stations. The invention comprises the following steps: s1: GNSS precision leveling, S2: on-site deployment of GNSS buoys, S3: installation of GNSS stationary reference station, S4: setting of GNSS observation time, S5: calculation of GNSS buoy SSH, S6: data filtering of the tidal signal SSH, S7: elimination of SSH ground level difference, S8: and the GNSS and the tide station are unified in vertical reference. The invention utilizes the high-precision GNSS height measurement buoy to observe the sea surface height information under the WGS-84 reference ellipsoid standard, avoids the three problems, is conveniently and economically arranged in the sea area near the ocean station, avoids the accumulation of the standard displacement error and the leveling error of the tide station, and unifies the standard of the tide station in the island and reef area of the open sea (including) in any sea area.)

1. A vertical reference detection method for a tide station by utilizing a GNSS buoy is characterized by comprising the following steps:

s1: measurement of GNSS precision levels: the height measurement of the GNSS buoy antenna is determined through precision measurement in a laboratory, and the height h1 from the phase center of the GNSS buoy antenna to the stationary water surface is determined;

s2: and (3) field deployment of GNSS buoys: the method comprises the following steps:

s21: the GNSS buoy is arranged in an open sea area near the ocean station;

s22: the GNSS buoy is connected through a floating ball fixed nearby, so that the horizontal position of the GNSS buoy is not greatly changed;

s23: the sampling frequency of the GNSS buoy is set to be 1 Hz;

s3: and (3) erecting a GNSS static reference station: erecting a GNSS static reference station in a land area of an ocean station for differential post-processing of GNSS buoy data;

s4: setting of GNSS observation time: in order to ensure that a complete tide is observed, the observation time of the GNSS buoy is not less than a certain number of days;

s5: calculation of the GNSS buoy SSH: after the measurement is finished, calculating the instantaneous sea level height SSH0 of 1Hz of the GNSS buoy antenna phase center by utilizing a PPK differential post-processing technology, and subtracting the antenna height h1 to obtain the actual instantaneous sea level height SSH 1:

in the formula:starting phase ambiguity for the GNSS buoy;the phase integer number from the starting epoch to the observation epoch of the GNSS buoy;the decimal part of the phase observation of the GNSS buoy; d rho is each residual error of the same observation epoch;

s6: data filtering of the tidal signal SSH: because the high-frequency SSH1 with the frequency of 1Hz contains wave fluctuation signals, the low-pass filtering in the frequency domain is adopted to eliminate the fluctuation signals of the GNSS buoy, the filtering window is set to be 60s, and the filtered residual SSH2 is ocean tide signals;

s7: elimination of SSH geodesic differences: because the space positions of the GNSS buoy and the tide station are different and the ocean geodetic planes of the GNSS buoy and the tide station are different, the geodetic level model is utilized for carrying out the correction, the height of the geodetic level model relative to a reference ellipsoid is interpolated according to the position of the GNSS buoy and the position of the tide station, the geodetic level height difference dh of the GNSS buoy and the tide station is obtained, and hd is subtracted from residual SSH2, so that a GNSS buoy tide signal SSH3 with the geodetic plane difference eliminated is obtained;

s8: unification of GNSS and tide station vertical reference: the method comprises the following steps:

s81: the GNSS buoy SSH and the tide station SSH are subjected to subtraction to obtain an interpolation time sequence of the GNSS buoy SSH and the tide station SSH;

s82: eliminating gross errors according to a triple error principle to obtain reliable difference information of the gross errors and the gross errors, counting the mean value and the standard deviation of the difference, and finally obtaining system parameters converted from the survey reference of the tide station to a WGS-84 ellipsoid and a precision evaluation result;

s83: and obtaining a linear coefficient of sea surface height difference of the GNSS and the tide station through regression analysis.

2. The method as claimed in claim 1, wherein in the step of deploying the GNSS buoy in S2 on site, no leveling point associated with the national elevation system exists in an area far from the continent, and the deployment point is configured to avoid occlusion by mountain signals, so as to prevent loss of GNSS signals.

3. The method as claimed in claim 1 or 2, wherein in S2, the GNSS buoy comprises a floating ball, and a GNSS positioning module, a communication module and a solar cell set disposed inside the floating ball, and the horizontal position of the GNSS buoy is not greatly changed by being connected to the floating ball fixed around.

4. The method as claimed in claim 1, wherein in the system parameters of WGS-84 ellipsoid in S82, WGS-84 is a new reference system obtained by correcting the change of origin and scale of NSWC9Z-2 reference system and rotating the reference meridian plane to coincide with the zero-degree meridian plane defined by BIH, the origin of WGS-84 coordinate system is at the earth centroid, the Z-axis is pointing to the polar direction of the agreement earth defined by BIH1984.0, the X-axis is pointing to the intersection point of the zero-degree meridian plane of BIH1984.0 and the CTP equator, and the Y-axis and the Z, X-axis form a right-hand coordinate system.

5. The method as claimed in claim 4, wherein in step S83, the tide station adds a set of GNSS antenna prior geodetic height data independent of GNSS antenna geodetic height data obtained by GNSS detection to a conventional GNSS positioning solution process in combination with a distance h1 between a phase center of a GNSS antenna and an instantaneous sea surface for a geodetic level height dh of a reference ellipsoid.

6. The method for detecting the vertical reference of the tidal station using GNSS buoy of claim 1 or 5, wherein in S83, the elevation reference of the tidal station and the elevation reference of the WGS-84 reference ellipsoid are different, and the slope obtained by regression analysis is equal to 1.0.

Technical Field

The invention relates to a vertical reference detection method for a tide station by utilizing a GNSS buoy, belonging to the technical field of vertical reference detection of tide stations.

Background

At present, the survey of the tidal observation station measuring datum mainly depends on GNSS leveling continuous survey, namely, an elevation relation is established between a GNSS base station and a tidal observation station datum point through GNSS precision leveling, so that a system height difference between a datum point elevation system of the tidal observation station and a WGS-84 reference ellipsoid of the GNSS is obtained, a mathematical reference ellipsoid under the geometric meaning obtained by the calculation of all tidal observation station benchmarks in China coastal is enabled, further, absolute sea level change and ocean geodetic vertical datum are enabled to be developed under a unified and strict reference surface, and a gap caused by the difference of elevation systems in different sea areas is avoided.

However, the method has the following disadvantages: the workload and the economic cost of leveling are high, the leveling difficulty of a complicated terrain area is high, and the error accumulation is large; II, secondly: the displacement error of the datum point of the tide gauge station can not be considered; and thirdly, a precise national 85 elevation system is lacked in an island tide-testing station far away from continental land, and the leveling continuous measurement result cannot be unified with the continental land.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides a vertical reference detection method for a tide station by utilizing a GNSS buoy.

The invention relates to a vertical reference detection method for a tide station by utilizing a GNSS buoy, which comprises the following steps:

s1: measurement of GNSS precision levels: the height measurement of the GNSS buoy antenna is determined through precision measurement in a laboratory, and the height h1 from the phase center of the GNSS buoy antenna to the stationary water surface is determined;

s2: and (3) field deployment of GNSS buoys: the method comprises the following steps:

s21: the GNSS buoy is arranged in an open sea area near the ocean station;

s22: the GNSS buoy is connected through a floating ball fixed nearby, so that the horizontal position of the GNSS buoy is not greatly changed;

s23: the sampling frequency of the GNSS buoy is set to be 1 Hz;

s3: and (3) erecting a GNSS static reference station: erecting a GNSS static reference station in a land area of an ocean station for differential post-processing of GNSS buoy data;

s4: setting of GNSS observation time: in order to ensure that a complete tide is observed, the observation time of the GNSS buoy is not less than a certain number of days;

s5: calculation of the GNSS buoy SSH: after the measurement is finished, calculating the instantaneous sea level height SSH0 of 1Hz of the GNSS buoy antenna phase center by utilizing a PPK differential post-processing technology, and subtracting the antenna height h1 to obtain the actual instantaneous sea level height SSH 1:

in the formula:starting phase ambiguity for the GNSS buoy;the phase integer number from the starting epoch to the observation epoch of the GNSS buoy;the decimal part of the phase observation of the GNSS buoy; d rho is each residual error of the same observation epoch;

s6: data filtering of the tidal signal SSH: because the high-frequency SSH1 with the frequency of 1Hz contains wave fluctuation signals, the low-pass filtering in the frequency domain is adopted to eliminate the fluctuation signals of the GNSS buoy, the filtering window is set to be 60s, and the filtered residual SSH2 is ocean tide signals;

s7: elimination of SSH geodesic differences: because the space positions of the GNSS buoy and the tide station are different and the ocean geodetic planes of the GNSS buoy and the tide station are different, the geodetic level model is utilized for carrying out the correction, the height of the geodetic level model relative to a reference ellipsoid is interpolated according to the position of the GNSS buoy and the position of the tide station, the geodetic level height difference dh of the GNSS buoy and the tide station is obtained, and hd is subtracted from residual SSH2, so that a GNSS buoy tide signal SSH3 with the geodetic plane difference eliminated is obtained;

s8: unification of GNSS and tide station vertical reference: the method comprises the following steps:

s81: the GNSS buoy SSH and the tide station SSH are subjected to subtraction to obtain an interpolation time sequence of the GNSS buoy SSH and the tide station SSH;

s82: eliminating gross errors according to a triple error principle to obtain reliable difference information of the gross errors and the gross errors, counting the mean value and the standard deviation of the difference, and finally obtaining system parameters converted from the survey reference of the tide station to a WGS-84 ellipsoid and a precision evaluation result;

s83: and obtaining a linear coefficient of sea surface height difference of the GNSS and the tide station through regression analysis.

Preferably, in the field deployment of the GNSS buoy in S2, the deployment point selects an area far from the continent where no leveling point associated with the national elevation system exists, and the deployment point should avoid mountain signal occlusion, so as to prevent GNSS signal loss.

Preferably, in S2, the GNSS buoy includes a floating ball, and a GNSS positioning module, a communication module, and a solar cell set disposed inside the floating ball, and is connected to the floating ball fixed around so that the horizontal position of the GNSS buoy does not change greatly.

Preferably, in the system parameters of the WGS-84 ellipsoid in the S82, the WGS-84 is a new reference system obtained by correcting the change of the origin and the scale of the NSWC9Z-2 reference system and rotating the reference meridian plane to be consistent with the zero-degree meridian plane defined by the BIH, the origin of the WGS-84 coordinate system is at the earth centroid, the Z axis points to the polar direction of the agreement on the earth defined by the BIH1984.0, the X axis points to the intersection point of the zero-degree meridian plane of the BIH1984.0 and the CTP equator, and the Y axis and the Z, X axis form a right-hand coordinate system.

Preferably, in S83, the tide station adds a set of GNSS antenna prior geodetic height data, which is independent of GNSS antenna geodetic height data obtained by GNSS detection, to the conventional GNSS positioning solution process with reference to the geodetic height difference dh of the reference ellipsoid and in combination with the distance h1 between the phase center of the GNSS antenna and the instantaneous sea surface.

Preferably, in the step S83, the slope obtained by regression analysis of the difference between the elevation standard of the tidal observation station and the elevation standard of the WGS-84 reference ellipsoid is equal to 1.0.

The invention has the beneficial effects that: according to the vertical reference detection method for the tide gauging station by utilizing the GNSS buoy, disclosed by the invention, the high-precision GNSS height measurement buoy is utilized to observe the sea surface height information under the reference of the WGS-84 reference ellipsoid, so that the three problems can be avoided, the vertical reference detection method can be conveniently and economically arranged in the sea area near the ocean station, the accumulation of the reference displacement error and the leveling error of the tide gauging station can be avoided, and the standard unification of the tide gauging station can be carried out in the island and reef area of the open sea (including) in any sea area.

Drawings

FIG. 1 is a flow diagram of the present invention.

FIG. 2 is a diagram of results of a standard unified tidal station and GNSS sea level height test.

FIG. 3 is a plot of a baseline unified tidal station and GNSS sea level height regression analysis.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1:

as shown in fig. 1 to 3, the method for detecting a vertical reference of a tide station using a GNSS buoy according to the present invention includes the following steps:

s1: measurement of GNSS precision levels: the height measurement of the GNSS buoy antenna is determined through precision measurement in a laboratory, and the height h1 from the phase center of the GNSS buoy antenna to the stationary water surface is determined;

s2: and (3) field deployment of GNSS buoys: the method comprises the following steps:

s21: the GNSS buoy is arranged in an open sea area near the ocean station;

s22: the GNSS buoy is connected through a floating ball fixed nearby, so that the horizontal position of the GNSS buoy is not greatly changed;

s23: the sampling frequency of the GNSS buoy is set to be 1 Hz;

s3: and (3) erecting a GNSS static reference station: erecting a GNSS static reference station in a land area of an ocean station for differential post-processing of GNSS buoy data;

s4: setting of GNSS observation time: in order to ensure that a complete tide is observed, the observation time of the GNSS buoy is not less than a certain number of days;

s5: calculation of the GNSS buoy SSH: after the measurement is finished, calculating the instantaneous sea level height SSH0 of 1Hz of the GNSS buoy antenna phase center by utilizing a PPK differential post-processing technology, and subtracting the antenna height h1 to obtain the actual instantaneous sea level height SSH 1:

in the formula:starting phase ambiguity for the GNSS buoy;the phase integer number from the starting epoch to the observation epoch of the GNSS buoy;the decimal part of the phase observation of the GNSS buoy; d rho is each residual error of the same observation epoch;

s6: data filtering of the tidal signal SSH: because the high-frequency SSH1 with the frequency of 1Hz contains wave fluctuation signals, the low-pass filtering in the frequency domain is adopted to eliminate the fluctuation signals of the GNSS buoy, the filtering window is set to be 60s, and the filtered residual SSH2 is ocean tide signals;

s7: elimination of SSH geodesic differences: because the space positions of the GNSS buoy and the tide station are different and the ocean geodetic planes of the GNSS buoy and the tide station are different, the geodetic level model is utilized for carrying out the correction, the height of the geodetic level model relative to a reference ellipsoid is interpolated according to the position of the GNSS buoy and the position of the tide station, the geodetic level height difference dh of the GNSS buoy and the tide station is obtained, and hd is subtracted from residual SSH2, so that a GNSS buoy tide signal SSH3 with the geodetic plane difference eliminated is obtained;

s8: unification of GNSS and tide station vertical reference: the method comprises the following steps:

s81: the GNSS buoy SSH and the tide station SSH are subjected to subtraction to obtain an interpolation time sequence of the GNSS buoy SSH and the tide station SSH;

s82: eliminating gross errors according to a triple error principle to obtain reliable difference information of the gross errors and the gross errors, counting the mean value and the standard deviation of the difference, and finally obtaining system parameters converted from the survey reference of the tide station to a WGS-84 ellipsoid and a precision evaluation result;

s83: and obtaining a linear coefficient of sea surface height difference of the GNSS and the tide station through regression analysis.

Specifically, in the field deployment of the GNSS buoy in S2, a leveling point associated with the national elevation system does not exist in an area far from the continent at the deployment point, and the deployment point should avoid mountain signal occlusion, so as to prevent GNSS signal loss.

Specifically, in S2, the GNSS buoy includes a floating ball, and a GNSS positioning module, a communication module, and a solar cell set disposed inside the floating ball, and is connected to the floating ball fixed around so that the horizontal position of the GNSS buoy does not change greatly.

Specifically, in the system parameters of the WGS-84 ellipsoid in the S82, the WGS-84 is a new reference system obtained by correcting the change of the origin and the scale of the NSWC9Z-2 reference system and rotating the reference meridian plane to coincide with the zero-degree meridian plane defined by the BIH, the origin of the WGS-84 coordinate system is at the earth centroid, the Z-axis points to the polar direction of the agreement earth defined by the BIH1984.0, the X-axis points to the intersection point of the zero-degree meridian plane of the BIH1984.0 and the CTP equator, and the Y-axis and the Z, X-axis constitute a right-hand coordinate system.

Specifically, in S83, for the geodetic level height difference dh of the reference ellipsoid, the tide station combines the distance h1 between the phase center of the GNSS antenna and the instantaneous sea surface, and adds a set of GNSS antenna prior geodetic height data, which is independent of GNSS antenna geodetic height data obtained by GNSS detection, to the conventional GNSS positioning calculation process.

Specifically, in S83, the slope obtained by regression analysis of the difference between the elevation standard of the tidal observation station and the elevation standard of the WGS-84 reference ellipsoid is equal to 1.0.

Example 2:

take an example of a marine test with a uniform measurement reference developed at a certain sea station in the Shandong coast.

Assuming that a GNSS height measurement buoy is distributed in an open sea area outside an ocean station to observe data for more than 1 day, and SSH of the GNSS buoy is obtained through a PPK method, so that the difference of the ground level is corrected, data filtering is carried out, the filtered GNSS sea level height data is differed with the tide station data, the difference between the elevation datum of the tide station and the elevation datum of a WGS-84 reference ellipsoid is 54cm, and the gradient obtained through regression analysis is equal to 1.0, wherein FIG. 2 shows the sea level height of the tide station and the GNSS after being unified, and FIG. 3 shows the sea level height regression analysis result of the GNSS and the tide station after being unified.

It should be noted that: the reference unification of the ocean station tide gauge system is important basic work for maintaining the national ocean vertical reference, developing the research on the absolute change of the ocean level and the like. At present, more than one hundred tidal observation stations are distributed along the sea in China, the measurement datum of each tidal observation station is 1985 national elevation datum, and the measurement datum is tidal observation data of the Qingdao tidal observation stations from 1952 to 1979, so that the extension of the elevation datum to the sea area has a plurality of technical problems, for example, gaps exist in the measurement datum of different sea areas, and the like. The problem can be solved by unifying the tide gauge datum to a geometric-significance reference ellipsoid (which is a globally unified high-precision continuous vertical reference surface). The current method may result in ignoring deformation errors of the tide station reference point in the vertical direction, thereby unifying the references with errors. In addition, the workload of land leveling is large, which is not beneficial to the large-scale tide gauge standard unification in the national range. Meanwhile, in some areas, national elevations of China are not transmitted (such as sea islands in the open sea), so that the leveling in the situation loses the meaning of unified reference. The GNSS height-measuring buoy is used for reference unification of the tide gauging stations, so that the introduction of reference point errors can be avoided, and the GNSS height-measuring buoy can be implemented in any tide gauging stations.

The invention has the beneficial effects that: according to the vertical reference detection method for the tide gauging station by utilizing the GNSS buoy, disclosed by the invention, the high-precision GNSS height measurement buoy is utilized to observe the sea surface height information under the reference of the WGS-84 reference ellipsoid, so that the three problems can be avoided, the vertical reference detection method can be conveniently and economically arranged in the sea area near the ocean station, the accumulation of the reference displacement error and the leveling error of the tide gauging station can be avoided, and the standard unification of the tide gauging station can be carried out in the island and reef area of the open sea (including) in any sea area.

The invention can be widely applied to the vertical reference detection occasions of the tide gauge station.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.