Marine geodetic reference network construction method based on joint networking of buoys and sea-land base stations

Abstract

The invention discloses an ocean geodetic reference network construction method for joint networking of buoys and sea-land base stations, which belongs to the technical field of ocean geodetic surveying, is used for constructing an ocean geodetic reference network, and comprises the following steps: solving to obtain underwater acoustic beacon coordinates of seabed base stations and a baseline length between receivers of the buoys and the underwater acoustic beacons of the seabed base stations; calculating to obtain the coordinates of the receivers of the land base stations, the instantaneous coordinates of the receivers of the buoys, the baseline length between the receivers of the land base stations and the receivers of the buoys, and the baseline length between the receivers of the land base stations; solving the baseline length between the receiver of the land base station and the underwater acoustic beacon of the seabed base station; and solving the coordinates of the land base station and the coordinates of the seabed base station. According to the method, the base line lengths among the land base station, the buoys and the seabed base station are obtained by using the relation equation among the land base station, the buoys and the seabed base station and adopting the least square method, so that the construction of the sea-land integrated geodetic survey reference network is realized.

Description

Technical Field

[0001] The invention discloses a method for constructing an ocean geodetic reference network by jointly networking buoys and sea and land base stations, and belongs to the technical field of ocean geodetic measurement. Background Art

[0002] Marine positioning generally utilizes a combination of GNSS and acoustic positioning, achieving seamless navigation between land and sea geodetic benchmarks and ocean navigation through the integration of sea surface and seabed control networks. Developing theories and methods for establishing land and sea geodetic benchmarks requires overcoming the technical bottlenecks in constructing consistent, continuous, and dynamic land and sea geodetic benchmarks, and developing theories, models, and methods for high-precision submarine positioning. While a relatively comprehensive geodetic benchmark has been established on land, existing spatial and gravity benchmarks lack effective coverage of the ocean, making the construction of a land and sea geodetic benchmark network difficult. Summary of the Invention

[0003] The purpose of the present invention is to provide a method for constructing a marine geodetic reference network by jointly networking buoys with sea and land base stations, so as to solve the problem in the prior art that the existing spatial reference and gravity reference fail to effectively cover the ocean and the marine and land geodetic reference network is difficult to construct.

[0004] The method for constructing a marine geodetic reference network by combining buoys with sea and land base stations includes: Step 1: The buoy is equipped with a GNSS receiver, an attitude sensor, and an acoustic transducer. Satellite positioning is used to obtain the instantaneous coordinates of the buoy's GNSS receiver, the attitude sensor obtains the instantaneous attitude of the buoy, and the acoustic transducer performs response ranging with the acoustic beacon of the seabed base station to obtain the coordinates of the acoustic beacon of the seabed base station and the baseline length between the buoy's GNSS receiver and the acoustic beacon of the seabed base station. Step 2: Synchronize the observations of the GNSS receiver of the land base station and the GNSS receiver of the buoy to construct a double-difference carrier phase baseline observation equation, and solve the coordinates of the GNSS receiver of the land base station, the instantaneous coordinates of the GNSS receiver of the buoy, the baseline length between the GNSS receiver of the land base station and the GNSS receiver of the buoy, and the baseline length between different GNSS receivers of the land base station; Step 3: Using the coordinates of the GNSS receiver of the land base station, the instantaneous coordinates of the GNSS receiver of the buoy, the baseline length between the GNSS receiver of the land base station and the GNSS receiver of the buoy, and the spatial positional relationship between the GNSS receiver of the land base station, the GNSS receiver of the buoy, and the hydroacoustic beacon of the seabed base station, the baseline length between the GNSS receiver of the land base station and the hydroacoustic beacon of the seabed base station is calculated; Step 4: Using the baseline length between the GNSS receivers of the land base stations and the baseline length between the GNSS receivers of the land base stations and the hydroacoustic beacon of the seabed base station, the coordinates of the land base stations and the seabed base stations are solved in three dimensions.

[0005] Step 1 includes: Step 1.1, using the offset parameters of the underwater acoustic transducer relative to the GNSS receiver in the horizontal, longitudinal and vertical directions , calculate the instantaneous coordinates of the buoy hydroacoustic transducer : ; Where, is the rotation matrix, Get the instantaneous attitude of the buoy for the attitude sensor, is the observation epoch, , is the total number of epochs, Obtain the instantaneous coordinates of the buoy GNSS receiver for satellite positioning.

[0006] Step 1 includes: Step 1.2, the underwater acoustic transducer and the underwater acoustic beacon of the seabed base station respond to measure the distance to obtain the instantaneous distance observation value , the relationship between the instantaneous coordinates of the underwater acoustic transducer and the instantaneous coordinates of the underwater acoustic beacon is: ; Where, is the straight-line distance between the underwater acoustic transducer and the underwater acoustic beacon, is the instantaneous coordinate of the hydroacoustic beacon; Use the least squares method to solve the coordinates of the underwater acoustic beacon: ; ; ; Where, is the parameter vector to be estimated, is the coordinate correction number, is the coefficient matrix, is the observation vector, Observation epoch The initial value of the baseline length between the underwater acoustic transducer and the underwater acoustic beacon is, Observation epoch The initial value of the instantaneous coordinate of the hydroacoustic beacon; The coordinates of the hydroacoustic beacon are , we get by calculation: ; ; ; Then the baseline length between the buoy GNSS receiver and the seabed base station hydroacoustic beacon is obtained : .

[0007] Step 2 includes: Step 2.1, the GNSS receiver of the land base station is the reference station, and the coordinates are known values The buoy's GNSS receiver is a mobile station, and the synchronized double-difference carrier phase baselines of the land base station's GNSS receiver and the buoy's GNSS receiver are in the same epoch. The observation equation at the moment is: ; ; ; Where, is the carrier wavelength, is the carrier phase double difference observation value, for The geometric distance between the buoy GNSS receiver and the satellite at the moment, for The geometric distance between the GNSS receiver of the land base station and the satellite at any moment, As the reference star, the satellite is received at the station Signal, is the unknown value of the whole cycle of the phase, For satellite Time buoy GNSS receiver coordinates, The reference star is Time buoy GNSS receiver coordinates, are the coordinates of the buoy GNSS receiver; The buoy GNSS receiver Instantaneous coordinates of the moment We can get: ; ; Where, for Time buoy GNSS receiver to satellite The instantaneous geometric distance, for Time buoy GNSS receiver to satellite The instantaneous geometric distance.

[0008] Step 2 includes, Step 2.2, at the same epoch, observing satellites, namely , can be composed of The observation equation is solved by the least square method to obtain the baseline length between the land base station GNSS receiver and the buoy GNSS receiver. : ; ; ; Where, , is the parameter vector to be estimated, is the baseline correction number, is the coefficient matrix, is the observation vector, For satellite coordinates; The baseline length between the GNSS receiver at the land base station and the GNSS receiver at the buoy for: .

[0009] Step 2 includes obtaining the baseline length between different land base station GNSS receivers .

[0010] Step 3 includes: Step 3.1, the coordinates of the GNSS receiver of the land base station, the instantaneous coordinates of the GNSS receiver of the buoy, the baseline length between the buoy GNSS receiver and the submerged buoy hydroacoustic beacon, and the baseline length between the GNSS receiver of the land base station and the hydroacoustic beacon of the seabed base station. The relationship equation is: .

[0011] Step 3 includes: Step 3.2, using the least squares method to solve the baseline length between the GNSS receiver of the land base station and the acoustic beacon of the seabed base station : ; ; ; Where, , is the parameter vector to be estimated, are the coordinate correction and baseline correction, is the coefficient matrix, is the observation vector, is the initial coordinate value of the seabed base station hydroacoustic beacon, is the initial value of the baseline length between the buoy GNSS receiver and the submerged acoustic beacon, is the initial value of the baseline length between the GNSS receiver of the land base station and the hydroacoustic beacon of the seabed base station; The baseline length between the GNSS receiver at the land base station and the hydroacoustic beacon at the seabed base station : .

[0012] Step 4 includes: Step 4.1, the GNSS receiver coordinates of a land base station in the geodetic reference network As a known starting point, the coordinates of another land base station GNSS receiver in the geodetic reference network are and the coordinates of the seabed base station hydroacoustic beacon As unknown parameters, the baseline length between the GNSS receivers of the land base stations is , the baseline length between the GNSS receivers of the two land base stations and the acoustic beacon of the seabed base station and The relationship equation is: ; ; .

[0013] Step 4 includes, step 4.2, using the least squares method to solve the coordinates of the unknown land base station GNSS receiver and the seabed base station hydroacoustic beacon: ; ; ; ; ; Where, , is the parameter vector to be estimated, is the coordinate correction number, is the coefficient matrix, is the observation vector, 、 and are the baseline instantaneous distance observation values between the GNSS receivers of the land base stations, and the baseline instantaneous distance observation values between the GNSS receivers of the two land base stations and the hydroacoustic beacon of the seabed base station, is the initial coordinate value of the land base station GNSS receiver, is the initial coordinate value of the seabed base station hydroacoustic beacon, is the initial value of the baseline length between the GNSS receivers of the land base station, and are the initial values of the baseline lengths between the GNSS receivers of the two land base stations and the acoustic beacon of the seabed base station, respectively. M and N are the two parts of the matrix; The coordinates of the land base station GNSS receiver are obtained as: ; ; ; The coordinates of the seabed base station hydroacoustic beacon are obtained as: ; ; .

[0014] Compared with the existing technology, the present invention has the following beneficial effects: the present invention can utilize the relationship equations among land base stations, buoys and seabed base stations, and adopt the least squares method to obtain the baseline lengths between land base stations, buoys and seabed base stations, thereby realizing the construction of a sea-land integrated geodetic reference network. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 Schematic diagram of the method for constructing a marine geodetic reference network by combining buoys with sea and land base stations according to the present invention; Figure 2 Flow chart of the method for constructing a marine geodetic reference network by jointly networking buoys and sea and land base stations according to the present invention; Figure 3 The calculation results of the land base station coordinates after the construction of the marine geodetic reference network provided by the embodiment of the present invention; Figure 4 The solution results of the seabed base station coordinates after the construction of the marine geodetic reference network provided by the embodiment of the present invention. DETAILED DESCRIPTION

[0016] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention are described clearly and completely below. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0017] The method for constructing a marine geodetic reference network by combining buoys with sea and land base stations includes: Step 1: The buoy is equipped with a GNSS receiver, an attitude sensor, and an acoustic transducer. Satellite positioning is used to obtain the instantaneous coordinates of the buoy's GNSS receiver, the attitude sensor obtains the instantaneous attitude of the buoy, and the acoustic transducer performs response ranging with the acoustic beacon of the seabed base station to obtain the coordinates of the acoustic beacon of the seabed base station and the baseline length between the buoy's GNSS receiver and the acoustic beacon of the seabed base station. Step 2: Synchronize the observations of the GNSS receiver of the land base station and the GNSS receiver of the buoy to construct a double-difference carrier phase baseline observation equation, and solve the coordinates of the GNSS receiver of the land base station, the instantaneous coordinates of the GNSS receiver of the buoy, the baseline length between the GNSS receiver of the land base station and the GNSS receiver of the buoy, and the baseline length between different GNSS receivers of the land base station; Step 3: Using the coordinates of the GNSS receiver of the land base station, the instantaneous coordinates of the GNSS receiver of the buoy, the baseline length between the GNSS receiver of the land base station and the GNSS receiver of the buoy, and the spatial positional relationship between the GNSS receiver of the land base station, the GNSS receiver of the buoy, and the hydroacoustic beacon of the seabed base station, the baseline length between the GNSS receiver of the land base station and the hydroacoustic beacon of the seabed base station is calculated; Step 4: Using the baseline length between the GNSS receivers of the land base stations and the baseline length between the GNSS receivers of the land base stations and the hydroacoustic beacon of the seabed base station, the coordinates of the land base stations and the seabed base stations are solved in three dimensions.

[0018] Step 1 includes: Step 1.1, using the offset parameters of the underwater acoustic transducer relative to the GNSS receiver in the horizontal, longitudinal and vertical directions , calculate the instantaneous coordinates of the buoy hydroacoustic transducer : ; Where, is the rotation matrix, Get the instantaneous attitude of the buoy for the attitude sensor, is the observation epoch, , is the total number of epochs, Obtain the instantaneous coordinates of the buoy GNSS receiver for satellite positioning.

[0019] Step 1 includes: Step 1.2, the underwater acoustic transducer and the underwater acoustic beacon of the seabed base station respond to measure the distance to obtain the instantaneous distance observation value , the relationship between the instantaneous coordinates of the underwater acoustic transducer and the instantaneous coordinates of the underwater acoustic beacon is: ; Where, is the straight-line distance between the underwater acoustic transducer and the underwater acoustic beacon, is the instantaneous coordinate of the hydroacoustic beacon; Use the least squares method to solve the coordinates of the underwater acoustic beacon: ; ; ; Where, is the parameter vector to be estimated, is the coordinate correction number, is the coefficient matrix, is the observation vector, Observation epoch The initial value of the baseline length between the underwater acoustic transducer and the underwater acoustic beacon is, Observation epoch The initial value of the instantaneous coordinate of the hydroacoustic beacon; The coordinates of the hydroacoustic beacon are , we get by calculation: ; ; ; Then the baseline length between the buoy GNSS receiver and the seabed base station hydroacoustic beacon is obtained : .

[0020] Step 2 includes: Step 2.1, the GNSS receiver of the land base station is the reference station, and the coordinates are known values The buoy's GNSS receiver is a mobile station, and the synchronized double-difference carrier phase baselines of the land base station's GNSS receiver and the buoy's GNSS receiver are in the same epoch. The observation equation at the moment is: ; ; ; Where, is the carrier wavelength, is the carrier phase double difference observation value, for The geometric distance between the buoy GNSS receiver and the satellite at the moment, for The geometric distance between the GNSS receiver of the land base station and the satellite at any moment, As the reference star, the satellite is received at the station Signal, is the unknown value of the whole cycle of the phase, For satellite Time buoy GNSS receiver coordinates, The reference star is Time buoy GNSS receiver coordinates, are the coordinates of the buoy GNSS receiver; The buoy GNSS receiver Instantaneous coordinates of the moment We can get: ; ; Where, for Time buoy GNSS receiver to satellite The instantaneous geometric distance, for Time buoy GNSS receiver to satellite The instantaneous geometric distance.

[0021] Step 2 includes, Step 2.2, at the same epoch, observing satellites, namely , can be composed of The observation equation is solved by the least square method to obtain the baseline length between the land base station GNSS receiver and the buoy GNSS receiver. : ; ; ; Where, , is the parameter vector to be estimated, is the baseline correction number, is the coefficient matrix, is the observation vector, For satellite coordinates; The baseline length between the GNSS receiver at the land base station and the GNSS receiver at the buoy for: .

[0022] Step 2 includes obtaining the baseline length between different land base station GNSS receivers .

[0023] Step 3 includes: Step 3.1, the coordinates of the GNSS receiver of the land base station, the instantaneous coordinates of the GNSS receiver of the buoy, the baseline length between the buoy GNSS receiver and the submerged buoy hydroacoustic beacon, and the baseline length between the GNSS receiver of the land base station and the hydroacoustic beacon of the seabed base station. The relationship equation is: .

[0024] Step 3 includes: Step 3.2, using the least squares method to solve the baseline length between the GNSS receiver of the land base station and the acoustic beacon of the seabed base station : ; ; ; Where, , is the parameter vector to be estimated, are the coordinate correction and baseline correction, is the coefficient matrix, is the observation vector, is the initial coordinate value of the seabed base station hydroacoustic beacon, is the initial value of the baseline length between the buoy GNSS receiver and the submerged acoustic beacon, is the initial value of the baseline length between the GNSS receiver of the land base station and the hydroacoustic beacon of the seabed base station; The baseline length between the GNSS receiver at the land base station and the hydroacoustic beacon at the seabed base station : .

[0025] Step 4 includes: Step 4.1, the GNSS receiver coordinates of a land base station in the geodetic reference network As a known starting point, the coordinates of another land base station GNSS receiver in the geodetic reference network are and the coordinates of the seabed base station hydroacoustic beacon As unknown parameters, the baseline length between the GNSS receivers of the land base stations is , the baseline length between the GNSS receivers of the two land base stations and the acoustic beacon of the seabed base station and The relationship equation is: ; ; .

[0026] Step 4 includes, step 4.2, using the least squares method to solve the coordinates of the unknown land base station GNSS receiver and the seabed base station hydroacoustic beacon: ; ; ; ; ; Where, , is the parameter vector to be estimated, is the coordinate correction number, is the coefficient matrix, is the observation vector, 、 and are the baseline instantaneous distance observation values between the GNSS receivers of the land base stations, and the baseline instantaneous distance observation values between the GNSS receivers of the two land base stations and the hydroacoustic beacon of the seabed base station, is the initial coordinate value of the land base station GNSS receiver, is the initial coordinate value of the seabed base station hydroacoustic beacon, is the initial value of the baseline length between the GNSS receivers of the land base station, and are the initial values of the baseline lengths between the GNSS receivers of the two land base stations and the acoustic beacon of the seabed base station, respectively. M and N are the two parts of the matrix; The coordinates of the land base station GNSS receiver are obtained as: ; ; ; The coordinates of the seabed base station hydroacoustic beacon are obtained as: ; ; .

[0027] like Figure 1 and Figure 2 A method for constructing a marine geodetic reference network by jointly networking buoys with sea and land base stations is shown. First, the buoy is equipped with a GNSS receiver, an attitude sensor, and an acoustic transducer. The acoustic transducer of the buoy responds and measures distance with the acoustic beacon of the seabed base station to obtain the baseline length between the buoy's GNSS receiver and the acoustic beacon of the seabed base station. Secondly, the GNSS receiver of the land base station and the buoy's GNSS receiver perform synchronous observations to construct a double-difference carrier phase baseline observation equation and solve the baseline length between the GNSS receiver of the land base station and the buoy's GNSS receiver. Thirdly, the spatial position relationship between the GNSS receiver of the land base station, the buoy's GNSS receiver, and the acoustic beacon of the seabed base station is used to calculate the baseline length between the GNSS receiver of the land base station and the acoustic beacon of the seabed base station. Finally, the baseline lengths between the GNSS receivers of the land base station and the baseline lengths between the GNSS receiver of the land base station and the acoustic beacon of the seabed base station are used to perform a three-dimensional solution for the coordinates of the land base station and the seabed base station to construct a land and sea integrated geodetic reference network.

[0028] Figure 3 and Figure 4The invention provides coordinate solution results of land base stations and seabed base stations after the construction of an ocean geodetic reference network comprising a joint network of buoys and land and sea base stations constructed based on an embodiment of the present invention. By constructing a relationship equation between the buoy hydroacoustic transducer and the seabed base station hydroacoustic beacon, the coordinates of the seabed base station hydroacoustic beacon are solved, and then the baseline length between the buoy GNSS receiver and the seabed base station hydroacoustic beacon is solved; a synchronous double-difference carrier phase baseline observation equation is constructed to solve the baseline length between the GNSS receiver of the land base station and the GNSS receiver of the buoy, as well as the baseline length between the GNSS receivers of the land base station; a relationship equation is constructed between the buoy GNSS receiver, the seabed base station hydroacoustic beacon and the land base station GNSS receiver, the baseline length between the GNSS receiver of the land base station and the seabed base station hydroacoustic beacon is solved, the coordinates of the land base station and the seabed base station are solved in three dimensions, and a land and sea integrated geodetic reference network is constructed, so that the accuracy of the constructed land and sea integrated geodetic reference network reaches the centimeter level.

[0029] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents, and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for constructing a marine geodetic reference network by combining buoys with sea and land base stations, characterized in that: include: Step 1: The buoy is equipped with a GNSS receiver, an attitude sensor, and an acoustic transducer. Satellite positioning is used to obtain the instantaneous coordinates of the buoy's GNSS receiver, the attitude sensor obtains the instantaneous attitude of the buoy, and the acoustic transducer performs response ranging with the acoustic beacon of the seabed base station to obtain the coordinates of the acoustic beacon of the seabed base station and the baseline length between the buoy's GNSS receiver and the acoustic beacon of the seabed base station. Step 2: Synchronize the observations of the GNSS receiver of the land base station and the GNSS receiver of the buoy to construct a double-difference carrier phase baseline observation equation, and solve the coordinates of the GNSS receiver of the land base station, the instantaneous coordinates of the GNSS receiver of the buoy, the baseline length between the GNSS receiver of the land base station and the GNSS receiver of the buoy, and the baseline length between different GNSS receivers of the land base station; Step 3: Using the coordinates of the GNSS receiver of the land base station, the instantaneous coordinates of the GNSS receiver of the buoy, the baseline length between the GNSS receiver of the land base station and the GNSS receiver of the buoy, and the spatial positional relationship between the GNSS receiver of the land base station, the GNSS receiver of the buoy, and the hydroacoustic beacon of the seabed base station, the baseline length between the GNSS receiver of the land base station and the hydroacoustic beacon of the seabed base station is calculated; Step 4: Using the baseline length between the GNSS receivers of the land base stations and the baseline length between the GNSS receivers of the land base stations and the hydroacoustic beacon of the seabed base station, the coordinates of the land base stations and the seabed base stations are solved in three dimensions.

2. The method for constructing a marine geodetic reference network by combining buoys with sea and land base stations according to claim 1, characterized in that: Step 1 includes: Step 1.1, using the offset parameters of the underwater acoustic transducer relative to the GNSS receiver in the horizontal, longitudinal and vertical directions , calculate the instantaneous coordinates of the buoy hydroacoustic transducer : ； Where, is the rotation matrix, Get the instantaneous attitude of the buoy for the attitude sensor, is the observation epoch, , is the total number of epochs, Obtain the instantaneous coordinates of the buoy GNSS receiver for satellite positioning.

3. The method for constructing a marine geodetic reference network by combining buoys with sea and land base stations according to claim 2, characterized in that: Step 1 includes: Step 1.2, the underwater acoustic transducer and the underwater acoustic beacon of the seabed base station respond to measure the distance to obtain the instantaneous distance observation value , the relationship between the instantaneous coordinates of the underwater acoustic transducer and the instantaneous coordinates of the underwater acoustic beacon is: ； Where, is the straight-line distance between the underwater acoustic transducer and the underwater acoustic beacon, is the instantaneous coordinate of the underwater acoustic beacon; Use the least squares method to solve the coordinates of the underwater acoustic beacon: ； ； ； Where, is the parameter vector to be estimated, is the coordinate correction number, is the coefficient matrix, is the observation vector, Observation epoch The initial value of the baseline length between the underwater acoustic transducer and the underwater acoustic beacon is, Observation epoch The initial value of the instantaneous coordinate of the hydroacoustic beacon; The coordinates of the hydroacoustic beacon are , we get by calculation: ； ； ； Then the baseline length between the buoy GNSS receiver and the seabed base station hydroacoustic beacon is obtained : 。 4. The method for constructing a marine geodetic reference network by combining buoys with sea and land base stations according to claim 3, characterized in that: Step 2 includes: Step 2.1, the GNSS receiver of the land base station is the reference station, and the coordinates are known values The buoy's GNSS receiver is a mobile station, and the synchronized double-difference carrier phase baselines of the land base station's GNSS receiver and the buoy's GNSS receiver are in the same epoch. The observation equation at the moment is: ； ； ； Where, is the carrier wavelength, is the carrier phase double difference observation value, for The geometric distance between the buoy GNSS receiver and the satellite at the moment, for The geometric distance between the GNSS receiver of the land base station and the satellite at any moment, As the reference star, the satellite is received at the station Signal, is the unknown value of the whole cycle of the phase, For satellite Time buoy GNSS receiver coordinates, The reference star is Time buoy GNSS receiver coordinates, are the coordinates of the buoy GNSS receiver; The buoy GNSS receiver Instantaneous coordinates of the moment We can get: ； ； Where, for Time buoy GNSS receiver to satellite The instantaneous geometric distance, for Time buoy GNSS receiver to satellite The instantaneous geometric distance.

5. The method for constructing a marine geodetic reference network by combining buoys with sea and land base stations according to claim 4, characterized in that: Step 2 includes, Step 2.2, at the same epoch, observing satellites, namely , can be composed of The observation equation is solved by the least square method to obtain the baseline length between the land base station GNSS receiver and the buoy GNSS receiver. : ； ； ； Where, , is the parameter vector to be estimated, is the baseline correction number, is the coefficient matrix, is the observation vector, For satellite coordinates; The baseline length between the GNSS receiver at the land base station and the GNSS receiver at the buoy for: 。 6. The method for constructing a marine geodetic reference network by combining buoys with sea and land base stations according to claim 5, characterized in that: Step 2 includes obtaining the baseline length between different land base station GNSS receivers .

7. The method for constructing a marine geodetic reference network by combining buoys with sea and land base stations according to claim 6, characterized in that: Step 3 includes: Step 3.1, the coordinates of the GNSS receiver of the land base station, the instantaneous coordinates of the GNSS receiver of the buoy, the baseline length between the buoy GNSS receiver and the submerged buoy hydroacoustic beacon, and the baseline length between the GNSS receiver of the land base station and the hydroacoustic beacon of the seabed base station. The relationship equation is: 。 8. The method for constructing a marine geodetic reference network by combining buoys with sea and land base stations according to claim 7, characterized in that: Step 3 includes: Step 3.2, using the least squares method to solve the baseline length between the GNSS receiver of the land base station and the acoustic beacon of the seabed base station : ； ； ； Where, , is the parameter vector to be estimated, are the coordinate correction and baseline correction, is the coefficient matrix, is the observation vector, is the initial coordinate value of the seabed base station hydroacoustic beacon, is the initial value of the baseline length between the buoy GNSS receiver and the submerged acoustic beacon, is the initial value of the baseline length between the GNSS receiver of the land base station and the hydroacoustic beacon of the seabed base station; The baseline length between the GNSS receiver at the land base station and the hydroacoustic beacon at the seabed base station : 。 9. The method for constructing a marine geodetic reference network by combining buoys with sea and land base stations according to claim 8, characterized in that: Step 4 includes: Step 4.1, the GNSS receiver coordinates of a land base station in the geodetic reference network As a known starting point, the coordinates of another land base station GNSS receiver in the geodetic reference network are and the coordinates of the seabed base station hydroacoustic beacon As unknown parameters, the baseline length between the GNSS receivers of the land base stations is , the baseline length between the GNSS receivers of the two land base stations and the acoustic beacon of the seabed base station and The relationship equation is: ； ； 。 10. The method for constructing a marine geodetic reference network by combining buoys with sea and land base stations according to claim 9, characterized in that: Step 4 includes, step 4.2, using the least squares method to solve the coordinates of the unknown land base station GNSS receiver and the seabed base station hydroacoustic beacon: ； ； ； ； ； Where, , is the parameter vector to be estimated, is the coordinate correction number, is the coefficient matrix, is the observation vector, 、 and are the baseline instantaneous distance observation values between the GNSS receivers of the land base stations, and the baseline instantaneous distance observation values between the GNSS receivers of the two land base stations and the hydroacoustic beacon of the seabed base station, is the initial coordinate value of the land base station GNSS receiver, is the initial coordinate value of the seabed base station hydroacoustic beacon, is the initial value of the baseline length between the GNSS receivers of the land base station, and are the initial values of the baseline lengths between the GNSS receivers of the two land base stations and the acoustic beacon of the seabed base station, respectively. M and N are the two parts of the matrix; The coordinates of the land base station GNSS receiver are obtained as: ； ； ； The coordinates of the seabed base station hydroacoustic beacon are obtained as: ； ； 。

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