Dual-antenna GNSS-R ground height change monitoring method and device

Abstract

The present application relates to a dual-antenna GNSS-R ground height change monitoring method and device, wherein the method includes: obtaining the position and area information of the target area to be monitored, so as to adjust the downward-looking antenna tilt angle and bracket height of the target ground-based dual-antenna GNSS-R, and control the target area to be monitored to be within the Fresnel reflection area of ​​the target ground-based dual-antenna GNSS-R; recording the parameter information of the target ground-based dual-antenna GNSS-R, and collecting and screening the GNSS observation data to obtain the satellite pair information corresponding to the GNSS observation data; determining the OPT file corresponding to the parameter information and the GNSS observation data, and obtaining the GNSS carrier phase observation value, and constructing a three-difference observation equation through the OPT file, the GNSS carrier phase observation value and the satellite pair information, so as to calculate the ground height change in the target area to be monitored based on the three-difference observation equation. Thus, the existing deformation monitoring method solves the problems of high monitoring cost, inability to provide continuous deformation information in a short time, and difficulty in realizing large-area observation.

Description

Technical Field

[0001] The present application relates to the field of GNSS remote sensing technology, and in particular to a dual-antenna GNSS-R ground height change monitoring method and device. Background Art

[0002] GNSS-R (Global Navigation Satellite System-Reflectometry) is a remote sensing technology that uses GNSS satellite reflection signals to monitor the physical parameters of the earth's surface. GNSS-R relies on different receiving platforms (ground-based, space-based and satellite) to receive GNSS reflection signals and combines electromagnetic wave scattering theory to extract surface information.

[0003] Although GNSS-R has shown great potential in land and ocean remote sensing (soil moisture, flood monitoring, sea surface wind and sea surface height), it is not widely used in deformation monitoring.

[0004] The traditional deformation monitoring method is to install multiple GNSS antennas on the deformable body and realize deformation monitoring by high-precision positioning of the antennas. However, this technology is only applicable to the estimation of deformation parameters of points and cannot achieve large-area observation. At the same time, this method requires the GNSS antenna to be directly fixed on the deformable body, which belongs to contact observation and cannot be deployed at certain deformation risk points. In addition, the non-contact three-dimensional laser scanning method can obtain three-dimensional deformation data, but it is expensive, easily affected by weather, and requires multiple measurements. The ground-based interferometric synthetic aperture radar (GB-InSAR) has high resolution, but its cost is relatively high. The spaceborne SAR can work for a long time, has a large monitoring range and high spatial resolution, but the SAR satellite has a long re-entry period and cannot provide continuous deformation information in a short time.

[0005] In summary, the existing deformation monitoring methods have high monitoring costs, cannot provide continuous deformation information in a short period of time, and are difficult to achieve large-area observation, which needs to be solved urgently. Summary of the invention

[0006] The present application provides a dual-antenna GNSS-R ground height change monitoring method and device to solve the problems of existing deformation monitoring methods, such as high monitoring cost, inability to provide continuous deformation information in a short period of time, and difficulty in achieving large-area observation.

[0007] A first aspect embodiment of the present application provides a dual-antenna GNSS-R ground height change monitoring method, comprising the following steps: obtaining position information and area information of a target area to be monitored, and adjusting the downward-looking antenna tilt angle and the bracket height of the target ground-based dual-antenna GNSS-R according to the position information and the area information to control the target area to be monitored to be within the Fresnel reflection area of ​​the target ground-based dual-antenna GNSS-R; collecting parameter information of the target ground-based dual-antenna GNSS-R when the target area to be monitored is in the Fresnel reflection area of ​​the target ground-based dual-antenna GNSS-R, and collecting GNSS observation data of the target ground-based dual-antenna GNSS-R, and performing quality screening processing on the GNSS observation data to obtain satellite pair information corresponding to the GNSS observation data; determining an OPT file corresponding to the parameter information and the GNSS observation data, and obtaining the GNSS carrier phase observation value of the target ground-based dual-antenna GNSS-R, and constructing a three-difference observation equation through the OPT file, the GNSS carrier phase observation value and the satellite pair information to calculate the ground height change in the target area to be monitored based on the three-difference observation equation.

[0008] Optionally, in one embodiment of the present application, the downward-looking antenna tilt angle and the bracket height of the target ground-based dual-antenna GNSS-R are adjusted according to the position information and the area information to control the target area to be monitored to be within the Fresnel reflection zone of the target ground-based dual-antenna GNSS-R, including: constructing an angle-adjustable connecting part and an adjustable height bracket between the direct antenna and the reflecting antenna in the target ground-based dual-antenna GNSS-R; adjusting the angle-adjustable connecting part and the adjustable height bracket according to the position information and the area information to continuously adjust the downward-looking antenna tilt angle and the bracket height of the target ground-based dual-antenna GNSS-R until the target area to be monitored is within the Fresnel reflection zone of the target ground-based dual-antenna GNSS-R.

[0009] Optionally, in one embodiment of the present application, the collecting of GNSS observation data of the target ground-based dual-antenna GNSS-R and the quality screening of the GNSS observation data to obtain satellite pair information corresponding to the GNSS observation data include: converting the GNSS observation data of the target ground-based dual-antenna GNSS-R into RINEX format to generate target observation data, wherein the target observation data includes direct antenna observation data and reflection antenna observation data; respectively determining the satellite zenith map, signal-to-noise ratio map, and cycle slip occurrence information corresponding to the direct antenna observation data and the reflection antenna observation data, and quality screening the target observation data according to the satellite zenith map, the signal-to-noise ratio map, and the cycle slip occurrence information to generate at least one target satellite information; and generating the satellite pair information based on the at least one target satellite information and the satellite zenith map.

[0010] Optionally, in one embodiment of the present application, the three-difference observation equation is constructed through the OPT file, the GNSS carrier phase observation value and the satellite pair information to calculate the ground height change in the target monitored area based on the three-difference observation equation, including: relative positioning of the ground symmetrical points of the direct antenna and the reflective antenna to obtain the distance between the direct antenna and the reflective antenna in the north direction at the ground symmetrical points; based on the OPT file, the GNSS carrier phase observation value and the satellite pair information, the altitude angle of the target ground-based dual-antenna GNSS-R, the antenna phase center spacing between the direct antenna and the reflective antenna, the horizontal projection length of the antenna phase center spacing, and the vertical distance from the ground to the antenna phase center of the reflective receiver of the target ground-based dual-antenna GNSS-R are obtained; according to the altitude angle, the horizontal projection length, the antenna phase center spacing, the vertical distance, the direct antenna A geometric model of the signal propagation path of the target ground-based dual-antenna GNSS-R is constructed based on the distance in the north direction of the reflection antenna at the symmetrical point on the ground and the preset cGNSS-R altimetry geometric relationship; based on the satellite pair information, the frequency band wavelength of the target satellite at the target time, the phase observation of the reflection receiver and the direct receiver of the target satellite, the clock difference between the reflection receiver and the direct receiver of the target satellite, and the ambiguity between the reflection receiver and the direct receiver of the target satellite and the phase observation are obtained; the single difference observation equation of the signal propagation path of the target satellite is determined according to the frequency band wavelength, the phase observation, the clock difference and the ambiguity, and the geometric model and the single difference observation equation are integrated to establish a GNSS-R altimetry model; based on the GNSS-R altimetry model, the triple difference observation equation is established, and the difference operation of adjacent epochs is performed through the triple difference observation equation to obtain the ground height change corresponding to each epoch.

[0011] Optionally, in one embodiment of the present application, after calculating the ground height change in the target area to be monitored, it also includes: drawing a corresponding scatter plot according to the ground height change corresponding to each epoch; calculating the standard deviation and root mean square error of the scatter plot, so as to evaluate the monitoring performance of the target area to be monitored through the standard deviation and the root mean square error.

[0012] Optionally, in one embodiment of the present application, the mathematical expression of the geometric model is:

[0013]

[0014] Among them, ρ r represents the reflection signal path length of the reflection antenna; ρ d represents the direct signal path length of the direct antenna; h represents the vertical distance from the ground to the antenna phase center of the reflection receiver of the target ground-based dual-antenna GNSS-R; d represents the antenna phase center spacing between the direct antenna and the reflection antenna; θ represents the altitude angle of the target ground-based dual-antenna GNSS-R; n represents the distance between the direct antenna and the reflection antenna in the north direction at the symmetrical point on the ground; d1 represents the horizontal projection length of the antenna phase center spacing

[0015] The second aspect of the present application provides a dual-antenna GNSS-R ground height change monitoring device, including: an adjustment module, used to obtain position information and area information of a target area to be monitored, and adjust the downward-looking antenna inclination angle and the bracket height of the target ground-based dual-antenna GNSS-R according to the position information and the area information, so as to control the target area to be monitored to be within the Fresnel reflection area of ​​the target ground-based dual-antenna GNSS-R; a screening module, used to collect parameter information of the target ground-based dual-antenna GNSS-R when the target area to be monitored is in the Fresnel reflection area of ​​the target ground-based dual-antenna GNSS-R, The GNSS observation data of the target ground-based dual-antenna GNSS-R is collected, and the quality screening process is performed on the GNSS observation data to obtain the satellite pair information corresponding to the GNSS observation data; the monitoring module is used to determine the parameter information and the OPT file corresponding to the GNSS observation data, and obtain the GNSS carrier phase observation value of the target ground-based dual-antenna GNSS-R, and construct a three-difference observation equation through the OPT file, the GNSS carrier phase observation value and the satellite pair information, so as to calculate the ground height change in the target monitored area based on the three-difference observation equation.

[0016] Optionally, in one embodiment of the present application, the adjustment module includes: a construction unit, used to construct an angle-adjustable connecting part and an adjustable height bracket between the direct antenna and the reflective antenna in the target ground-based dual-antenna GNSS-R; an adjustment unit, used to adjust the angle-adjustable connecting part and the adjustable height bracket according to the position information and the area information, so as to continuously adjust the downward-looking antenna inclination angle and the bracket height of the target ground-based dual-antenna GNSS-R until the target area to be monitored is within the Fresnel reflection area of ​​the target ground-based dual-antenna GNSS-R.

[0017] Optionally, in one embodiment of the present application, the screening module includes: a conversion unit, used to convert the GNSS observation data of the target ground-based dual-antenna GNSS-R into RINEX format to generate target observation data, wherein the target observation data includes direct antenna observation data and reflection antenna observation data; a first determination unit, used to respectively determine the satellite zenith map, signal-to-noise ratio map and cycle slip occurrence information corresponding to the direct antenna observation data and the reflection antenna observation data, and perform quality screening processing on the target observation data according to the satellite zenith map, the signal-to-noise ratio map and the cycle slip occurrence information to generate at least one target satellite information; a generation unit, used to generate the satellite pair information based on the at least one target satellite information and the satellite zenith map.

[0018] Optionally, in one embodiment of the present application, the monitoring module includes: a relative positioning unit, used to relatively position the ground symmetrical points of the direct antenna and the reflective antenna to obtain the distance between the direct antenna and the reflective antenna in the north direction at the ground symmetrical point; a first acquisition unit, used to acquire the altitude angle of the target ground-based dual-antenna GNSS-R, the antenna phase center spacing between the direct antenna and the reflective antenna, the horizontal projection length of the antenna phase center spacing, and the vertical distance from the ground to the antenna phase center of the reflective receiver of the target ground-based dual-antenna GNSS-R based on the OPT file, the GNSS carrier phase observation value and the satellite pair information; a second determination unit, used to determine the altitude angle, the horizontal projection length, the antenna phase center spacing, the vertical distance, the distance between the direct antenna and the reflective antenna in the north direction at the ground symmetrical point and a preset cGNS The S-R altimetry geometric relationship constructs a geometric model of the signal propagation path of the target ground-based dual-antenna GNSS-R; a second acquisition unit is used to acquire the frequency band wavelength of the target satellite at the target time, the phase observation of the reflection receiver and the direct receiver of the target satellite, the clock difference between the reflection receiver and the direct receiver of the target satellite, and the ambiguity between the reflection receiver and the direct receiver of the target satellite and the phase observation based on the satellite pair information; a fusion unit is used to determine the single difference observation equation of the signal propagation path of the target satellite according to the frequency band wavelength, the phase observation, the clock difference and the ambiguity, and fuse the geometric model and the single difference observation equation to establish a GNSS-R altimetry model; an execution unit is used to establish the three-difference observation equation based on the GNSS-R altimetry model, and perform the difference operation of adjacent epochs through the three-difference observation equation to obtain the ground height change corresponding to each epoch.

[0019] Optionally, in one embodiment of the present application, it also includes: a drawing module, which is used to draw a corresponding scatter plot according to the ground height change corresponding to each epoch after calculating the ground height change in the target monitored area; an evaluation module, which is used to calculate the standard deviation and root mean square error of the scatter plot, so as to evaluate the monitoring performance of the target monitored area through the standard deviation and the root mean square error.

[0020] Optionally, in one embodiment of the present application, the mathematical expression of the geometric model is:

[0021]

[0022] Among them, ρ r represents the reflection signal path length of the reflection antenna; ρ drepresents the direct signal path length of the direct antenna; h represents the vertical distance from the ground to the antenna phase center of the reflection receiver of the target ground-based dual-antenna GNSS-R; d represents the antenna phase center spacing between the direct antenna and the reflection antenna; θ represents the altitude angle of the target ground-based dual-antenna GNSS-R; n represents the distance between the direct antenna and the reflection antenna in the north direction at the symmetrical point on the ground; d1 represents the horizontal projection length of the antenna phase center spacing.

[0023] The third aspect of the present application provides an electronic device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the dual-antenna GNSS-R ground height change monitoring method as described in the above embodiment.

[0024] The fourth aspect embodiment of the present application provides a computer-readable storage medium, which stores a computer program, and when the program is executed by a processor, it implements the above dual-antenna GNSS-R ground height change monitoring method.

[0025] The fifth aspect embodiment of the present application provides a computer program product, including a computer program, which is executed to implement the above-mentioned dual-antenna GNSS-R ground height change monitoring method.

[0026] Therefore, the embodiments of the present application have the following beneficial effects:

[0027] The embodiment of the present application can obtain the position information and area information of the target area to be monitored, and adjust the downward antenna tilt angle and bracket height of the target ground-based dual-antenna GNSS-R according to the position information and area information to control the target area to be monitored to be in the Fresnel reflection area of ​​the target ground-based dual-antenna GNSS-R; collect the parameter information of the target ground-based dual-antenna GNSS-R when the target area to be monitored is in the Fresnel reflection area of ​​the target ground-based dual-antenna GNSS-R, and collect the GNSS observation data of the target ground-based dual-antenna GNSS-R, and perform quality screening on the GNSS observation data to obtain the satellite pair information corresponding to the GNSS observation data; determine the OPT file corresponding to the parameter information and the GNSS observation data, and obtain the GNSS carrier phase observation value of the target ground-based dual-antenna GNSS-R, and construct a three-difference observation equation through the OPT file, the GNSS carrier phase observation value and the satellite pair information, so as to calculate the ground height change in the target area to be monitored based on the three-difference observation equation. The present application can continuously monitor the specified ground position and area by designing the angle between the parts and the vertical direction and the height of the bracket, which is conducive to coping with more monitoring environments. This solves the problems of existing deformation monitoring methods, such as high monitoring costs, inability to provide continuous deformation information in a short period of time, and difficulty in achieving large-area observation.

[0028] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0030] Figure 1 A flowchart of a dual-antenna GNSS-R ground height change monitoring method provided according to an embodiment of the present application;

[0031] Figure 2 A schematic diagram of an antenna connection part with an adjustable reflective antenna tilt angle provided in accordance with an embodiment of the present application;

[0032] Figure 3 A schematic diagram of a liftable bracket provided for an embodiment of the present application;

[0033] Figure 4 A satellite zenith map during an observation period provided for one embodiment of the present application;

[0034] Figure 5 A schematic diagram of a GNSS signal propagation path provided for an embodiment of the present application;

[0035] Figure 6A scatter plot of ground height changes monitored by a combination of an E14 satellite of a Galileo satellite navigation system and a C03 satellite of a BeiDou satellite navigation system provided in one embodiment of the present application;

[0036] Figure 7 A scatter plot of ground height changes monitored by a combination of an E14 satellite of a Galileo satellite navigation system and a C07 satellite of a BeiDou satellite navigation system provided in one embodiment of the present application;

[0037] Figure 8 A schematic diagram of execution logic of a dual-antenna GNSS-R ground height change monitoring method provided for one embodiment of the present application;

[0038] Fig. 9 This is an example diagram of a dual-antenna GNSS-R ground height change monitoring device according to an embodiment of the present application;

[0039] Fig.10 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application.

[0040] Among them, 10-dual-antenna GNSS-R ground height change monitoring device; 100-adjustment module, 200-screening module, 300-monitoring module; 1001-memory, 1002-processor, 1003-communication interface. DETAILED DESCRIPTION

[0041] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0042] The following describes the dual-antenna GNSS-R ground height change monitoring method and device according to an embodiment of the present application with reference to the accompanying drawings. In response to the problems mentioned in the above background technology, the present application provides a dual-antenna GNSS-R ground height change monitoring method, in which the location information and area information of the target area to be monitored are obtained, and the downward-looking antenna tilt angle and the bracket height of the target ground-based dual-antenna GNSS-R are adjusted according to the location information and area information to control the target area to be monitored to be within the Fresnel reflection area of ​​the target ground-based dual-antenna GNSS-R; the parameter information of the target ground-based dual-antenna GNSS-R is collected when the target area to be monitored is in the Fresnel reflection area of ​​the target ground-based dual-antenna GNSS-R, and the GNSS observation data of the target ground-based dual-antenna GNSS-R is collected, and the GNSS observation data is quality screened to obtain the satellite pair information corresponding to the GNSS observation data; the OPT file corresponding to the parameter information and the GNSS observation data is determined, and the GNSS carrier phase observation value of the target ground-based dual-antenna GNSS-R is obtained, and a three-difference observation equation is constructed through the OPT file, the GNSS carrier phase observation value and the satellite pair information, so as to calculate the ground height change in the target area to be monitored based on the three-difference observation equation. This application can continuously monitor the specified ground position and area by designing the angle between the parts and the vertical direction and the height of the bracket, which is conducive to coping with more monitoring environments. This solves the problems of the existing deformation monitoring methods, such as high monitoring cost, inability to provide continuous deformation information in a short period of time, and difficulty in achieving large-area observation.

[0043] Specifically, Figure 1 A flowchart of a dual-antenna GNSS-R ground height change monitoring method provided in an embodiment of the present application.

[0044] like Figure 1 As shown, the dual-antenna GNSS-R ground height change monitoring method includes the following steps:

[0045] In step S101, the location information and area information of the target area to be monitored are obtained, and the downward-looking antenna tilt angle and the bracket height of the target ground-based dual-antenna GNSS-R are adjusted according to the location information and the area information to control the target area to be monitored to be within the Fresnel reflection area of ​​the target ground-based dual-antenna GNSS-R.

[0046] The embodiments of the present application can first design and manufacture antenna connecting parts with adjustable inclination angle of the reflecting antenna and a bracket with adjustable height, and adjust the inclination angle of the downward-looking antenna and the height of the bracket according to the location and area size of the area to be monitored to ensure that the monitoring position is within the Fresnel reflection area.

[0047] It should be noted that in terms of hardware design, traditional dual antennas are installed opposite to each other in the vertical direction, and the installation height of the antenna is fixed, and the flexibility of the installation method is poor. Compared with the traditional installation method, the embodiment of the present application designs a hardware facility with more flexible installation. The direct antenna is designed to be vertically upward, and the installation angle of the reflecting antenna can be adjusted. The position and area of ​​the Fresnel reflection zone can be changed by adjusting the installation angle of the reflecting antenna.

[0048] Therefore, the mounting bracket of the embodiment of the present application can adjust the installation position of the antenna to change the position and area of ​​the Fresnel reflection zone, thereby being able to cope with more monitoring environments.

[0049] Optionally, in one embodiment of the present application, the downward-looking antenna tilt angle and the bracket height of the target ground-based dual-antenna GNSS-R are adjusted according to the position information and the area information to control the target monitored area to be within the Fresnel reflection zone of the target ground-based dual-antenna GNSS-R, including: constructing an angle-adjustable connecting part and an adjustable height bracket between the direct antenna and the reflecting antenna in the target ground-based dual-antenna GNSS-R; adjusting the angle-adjustable connecting part and the adjustable height bracket according to the position information and the area information to continuously adjust the downward-looking antenna tilt angle and the bracket height of the target ground-based dual-antenna GNSS-R until the target monitored area is within the Fresnel reflection zone of the target ground-based dual-antenna GNSS-R.

[0050] In the specific implementation process, the embodiment of the present application designs a part that can adjust the angle between the two antennas (that is, an angle-adjustable connecting part), such as Figure 2 As shown, the main body of the antenna connection part can be circular, the nut connecting the direct antenna is fixed, and the nut connecting the reflective antenna is adjustable; during installation, the direct antenna is fixed vertically upward, and the reflective antenna is adjusted within 180 degrees below the direct antenna, and the angle between the two antennas can be adjusted to 180°, 165°, 150°, 135°, 120°, 105°; at the same time, in order to cope with more monitoring environments, the embodiments of the present application can also be designed with a liftable bracket, such as Figure 3 as shown (i.e. adjustable height bracket).

[0051] The hardware of the embodiment of the present application is composed of an antenna connector (i.e., an angle-adjustable connector) and a liftable bracket. By changing the angle between the two antennas and the bracket height, the area to be monitored can be located within the Fresnel reflection zone. The larger the angle between the two antennas, the larger the Fresnel reflection zone and the farther away from the device; the smaller the angle between the two antennas, the smaller the Fresnel reflection zone and the closer to the device. The higher the bracket height, the farther the Fresnel reflection zone is from the device; the lower the bracket height, the closer the Fresnel reflection zone is to the device.

[0052] Therefore, the embodiment of the present application determines the installation position of the instrument according to the area to be detected and the surrounding environment, adjusts the angle between the reflective antenna and the direct antenna, and effectively ensures that the area to be monitored is located in the Fresnel reflection zone.

[0053] In step S102, parameter information of the target ground-based dual-antenna GNSS-R is collected when the target area to be monitored is in the Fresnel reflection area of ​​the target ground-based dual-antenna GNSS-R, and GNSS observation data of the target ground-based dual-antenna GNSS-R is collected, and the GNSS observation data is quality screened to obtain satellite pair information corresponding to the GNSS observation data.

[0054] Furthermore, the embodiments of the present application can record parameter information of the target ground-based dual-antenna GNSS-R, such as the angle between the two antennas, the horizontal azimuth, and the antenna height, and continuously collect ground-based dual-antenna GNSS-R observation data, and convert the GNSS-R observation data into a format. At the same time, the quality of the two sets of data collected by the upward-looking antenna and the downward-looking antenna can be screened according to selection indicators such as the frequency of cycle slips, the altitude angle, and the signal-to-noise ratio, so that the selected data can be combined into a satellite pair.

[0055] Optionally, in one embodiment of the present application, GNSS observation data of a target ground-based dual-antenna GNSS-R is collected, and the GNSS observation data is quality screened to obtain satellite pair information corresponding to the GNSS observation data, including: converting the GNSS observation data of the target ground-based dual-antenna GNSS-R into RINEX format to generate target observation data, wherein the target observation data includes direct antenna observation data and reflection antenna observation data; respectively determining the satellite zenith map, signal-to-noise ratio map, and cycle slip occurrence information corresponding to the direct antenna observation data and the reflection antenna observation data, and quality screening the target observation data according to the satellite zenith map, the signal-to-noise ratio map, and the cycle slip occurrence information to generate at least one target satellite information; and generating satellite pair information based on at least one target satellite information and the satellite zenith map.

[0056] Specifically, the embodiments of the present application can first continuously collect ground-based dual-antenna GNSS-R observation data, check the data integrity and calibrate the starting epoch, and convert the GNSS observation data into RINEX format.

[0057] In the actual implementation process, the embodiment of the present application can select a closed grassland as the experimental site. There are no pedestrians or other buildings around the experimental site, but there are some trees. The experimental duration can be set to 2 hours and 15 minutes.

[0058] Secondly, when screening data quality, the embodiment of the present application can draw satellite zenith maps of the direct antenna and the reflective antenna respectively (such as Figure 4The GNSS observation data with high satellite elevation angle and less cycle slip during the observation period are selected by using the signal-to-noise ratio diagram and the cycle slip occurrence, etc. Since the reflection antenna receives the GNSS signal with multipath effect, the signal used is received by the reflection antenna after being reflected by the ground. Some signals are not received by the reflection antenna after being reflected by other objects such as trees, stones, and pedestrians. Some signals received by the reflection antenna will have cycle slips. In the process of screening data, the satellite data with less cycle slips will be screened out, that is, the reflection antenna receives the signal after being reflected by the ground.

[0059] Afterwards, the embodiments of the present application can select the E14 satellite of the Galileo satellite system and the C03 and C07 satellites of the Beidou satellite system through information such as the satellite zenith map and the signal-to-noise ratio; finally, the embodiments of the present application can form a satellite pair based on the satellite zenith map with good GNSS data quality selected and combined with the satellite zenith map of the direct antenna and the reflection antenna to collect data, thereby providing reliable data guidance and basis for the construction of the subsequent three-difference observation equation.

[0060] In step S103, the OPT file corresponding to the parameter information and GNSS observation data is determined, and the GNSS carrier phase observation value of the target ground-based dual-antenna GNSS-R is obtained. The three-difference observation equation is constructed through the OPT file, GNSS carrier phase observation value and satellite pair information to calculate the ground height change in the target monitored area based on the three-difference observation equation.

[0061] Those skilled in the art should understand that a set of GNSS observation data in the RINEX format may have several files. Due to the characteristics of dual antennas, there are multiple observation files, and it is troublesome to read them one by one.

[0062] Therefore, the embodiments of the present application can configure the OPT file input by the program based on the algorithm design framework and the relevant parameter information recorded during the experiment. The OPT file includes the RINEX files of the direct antenna and the reflective antenna, the angle between the two antennas is 135°, the horizontal azimuth angle is [60°, 215°], L1=0.19m, L2=0.18m, the satellite minimum altitude angle is greater than 10°, etc.

[0063] Afterwards, the embodiments of the present application can analyze the geometric relationship of the signal propagation path, and combine it with the single-difference observation equation to obtain the GNSS-R altimetry model; further, the embodiments of the present application can construct a triple-difference observation equation to eliminate multiple errors, and output the ground height change per epoch, thereby drawing a scatter plot of the ground height change.

[0064] Optionally, in one embodiment of the present application, a three-difference observation equation is constructed through the OPT file, GNSS carrier phase observation values ​​and satellite pair information to calculate the ground height change in the target monitored area based on the three-difference observation equation, including: relative positioning of the ground symmetrical points of the direct antenna and the reflecting antenna to obtain the distance in the north direction between the direct antenna and the reflecting antenna at the ground symmetrical points; based on the OPT file, GNSS carrier phase observation values ​​and satellite pair information, the altitude angle of the target ground-based dual-antenna GNSS-R, the antenna phase center spacing between the direct antenna and the reflecting antenna, the horizontal projection length of the antenna phase center spacing and the vertical distance from the ground to the antenna phase center of the reflection receiver of the target ground-based dual-antenna GNSS-R are obtained; according to the altitude angle, horizontal projection length, antenna phase center spacing, vertical distance, the distance between the direct antenna and the reflecting antenna The geometric model of the signal propagation path of the target ground-based dual-antenna GNSS-R is constructed based on the distance of the ground symmetrical points in the north direction and the preset cGNSS-R altimetry geometric relationship; based on the satellite pair information, the frequency band wavelength of the target satellite at the target time, the phase observations of the reflection receiver and the direct receiver of the target satellite, the clock difference between the reflection receiver and the direct receiver of the target satellite, and the ambiguity between the reflection receiver and the direct receiver of the target satellite and the phase observation are obtained; the single-difference observation equation of the signal propagation path of the target satellite is determined according to the frequency band wavelength, phase observations, clock difference and ambiguity, and the geometric model and the single-difference observation equation are integrated to establish the GNSS-R altimetry model; based on the GNSS-R altimetry model, the triple-difference observation equation is established, and the difference operation of adjacent epochs is performed through the triple-difference observation equation to obtain the ground height change corresponding to each epoch.

[0065] In the specific implementation process, the embodiment of the present application can use the basic information such as the satellite elevation angle obtained by processing the GNSS information obtained by the direct antenna and the reflective antenna during data processing, and perform relative positioning of the ground symmetrical points of the direct antenna and the reflective antenna to obtain the ENU information between the two, and combine the OPT file, GNSS carrier phase observation value, satellite pair information and cGNSS-R height measurement geometry relationship to obtain the following formula:

[0066] ρ r -ρ d =(2h+d)*sinθ

[0067] Among them, ρ r represents the length of the reflected signal path; ρ d is the length of the direct signal path; h is the vertical distance from the ground to the phase center of the reflection receiver; d is the vertical distance between the direct antenna and the reflection antenna phase (this parameter can be obtained by actual measurement); θ is the altitude angle of the GNSS satellite.

[0068] Optionally, in one embodiment of the present application, the mathematical expression of the geometric model is:

[0069]

[0070] Among them, ρ r represents the reflected signal path length of the reflecting antenna; ρ d represents the direct signal path length of the direct antenna; h represents the vertical distance from the ground to the antenna phase center of the reflector receiver of the target ground-based dual-antenna GNSS-R; d represents the antenna phase center spacing between the direct antenna and the reflector antenna; θ represents the altitude angle of the target ground-based dual-antenna GNSS-R; n represents the distance in the north direction between the direct antenna and the reflector antenna at the symmetrical point on the ground; d1 represents the horizontal projection length of the antenna phase center spacing.

[0071] It should be noted that, since the antenna installation method of the embodiment of the present application is different from the traditional method, the geometric relationship (ie, the geometric model) of the signal propagation path will also change, so the above formula can be changed to:

[0072]

[0073] Wherein, d is the vertical distance between the direct antenna and the reflector antenna phase; n is the distance in the north direction between the symmetric points of the direct antenna and the reflector antenna in the horizontal plane obtained by relative positioning; d1 is the horizontal projection length between the phase centers of the direct antenna and the reflector antenna.

[0074] Furthermore, the embodiment of the present application can establish a single difference observation equation according to the frequency band wavelength of the target satellite at the target time, the phase observation of the reflection receiver and the direct receiver of the target satellite, the clock difference between the reflection receiver and the direct receiver of the target satellite, and the ambiguity between the reflection receiver and the direct receiver of the target satellite and the phase observation, as shown in the following formula:

[0075]

[0076] The GNSS-R height measurement model can be obtained by fusing the geometric relationship of the above signal propagation path (i.e., geometric model) with the single-difference observation equation, as shown in the following formula:

[0077]

[0078] Afterwards, the embodiment of the present application can obtain the three-difference observation equation according to the GNSS-R altimetry model, eliminate multiple errors through the three-difference observation equation, and perform the difference between adjacent epochs to obtain the ground height change Δh, as described in the following formula:

[0079]

[0080] in, and Respectively expressed in t i The path lengths of the signal from satellite 1 (i.e., the target satellite) to the reflector antenna and the direct antenna at time (i.e., the target time) are as follows: Figure 5 As shown; λ1 represents the wavelength of a certain frequency band of GNSS; and The L1 phase observations from satellite 1 are obtained by the reflection receiver and the direct receiver respectively; c is the speed of light; δt rd (t i ) is the difference between the direct receiver and the reflected receiver clock errors; and are the ambiguities of the phase observations between the reflection receiver and the direct receiver and satellite 1 respectively; N 1 represent N 2 represent θ 1 and θ 2 are the altitude angles of satellite 1 and satellite 2 respectively.

[0081] Optionally, in one embodiment of the present application, after calculating the ground height change in the target area to be monitored, it also includes: drawing a corresponding scatter plot according to the ground height change corresponding to each epoch; calculating the standard deviation and root mean square error of the scatter plot, so as to evaluate the monitoring performance of the target area to be monitored through the standard deviation and root mean square error.

[0082] Afterwards, the embodiments of the present application can continuously output the ground height change Δh per epoch, draw a scatter plot of the ground height change, and calculate evaluation indicators such as STD and RMSE of the output results to evaluate the monitoring performance of the target monitored area through standard deviation and root mean square error.

[0083] Therefore, the embodiments of the present application can establish a triple-difference observation equation without ambiguity fixation, thereby reducing the error caused by the inability to fix the ambiguity or fixation errors due to frequent cycle slips, so as to effectively monitor the changes in ground height.

[0084] Figure 6 The scatter plot of the ground height change monitored by the E14 satellite of the Galileo satellite navigation system and the C03 satellite of the Beidou satellite navigation system is shown in Figure 2. Figure 6 As shown, its STD = 0.001931975m, RMSE = 0.00193324m; Figure 7 The scatter plot of the ground height change monitored by the E14 satellite of the Galileo satellite navigation system and the C07 satellite of the Beidou satellite navigation system is shown in Figure 2. Figure 7 As shown, its STD = 0.001976237m and RMSE = 0.00197652m.

[0085] It is understandable that the traditional method requires the deployment of multiple antenna networks to monitor the deformation of a planar area. A single antenna can only monitor the deformation of that point. Figure 6 and Figure 7 It can be seen that the embodiment of the present application can continuously monitor the change in ground height with an accuracy of up to centimeter level; in addition, the embodiment of the present application can directly monitor the deformation of a planar area without the need to deploy other antennas.

[0086] The following describes the execution logic of the dual-antenna GNSS-R ground height change monitoring method of the present application in conjunction with the accompanying drawings.

[0087] Figure 8 FIG. 1 is a schematic diagram of the execution logic of the dual-antenna GNSS-R ground height change monitoring method of the present application. Figure 8 As shown, the execution process of the dual-antenna GNSS-R ground height change monitoring method of the present application is as follows:

[0088] S801: Design and manufacture antenna connection parts with adjustable reflector antenna inclination and height-adjustable bracket;

[0089] S801: Determine the inclination angle of the reflective antenna and the height of the bracket according to the position and area of ​​the area to be detected;

[0090] S801: The direct antenna receives the direct signal from the GNSS satellite, and the reflective antenna receives the GNSS signal reflected by the ground;

[0091] S801: GNSS signal preprocessing and format conversion, filter out data with good observation quality, and configure OPT file;

[0092] S801: Analyze the geometric relationship of the signal propagation path and combine it with the single-difference observation equation to obtain the GNSS-R height measurement model;

[0093] S801: Construct triple-difference observation equations to eliminate multiple errors and output the ground height change at each epoch.

[0094] According to the dual-antenna GNSS-R ground height change monitoring method proposed in the embodiment of the present application, the position information and area information of the target area to be monitored are obtained, and the downward-looking antenna tilt angle and the bracket height of the target ground-based dual-antenna GNSS-R are adjusted according to the position information and area information to control the target area to be monitored to be within the Fresnel reflection area of ​​the target ground-based dual-antenna GNSS-R; the parameter information of the target ground-based dual-antenna GNSS-R is collected when the target area to be monitored is in the Fresnel reflection area of ​​the target ground-based dual-antenna GNSS-R, and the GNSS observation data of the target ground-based dual-antenna GNSS-R is collected, and the GNSS observation data is quality screened to obtain the satellite pair information corresponding to the GNSS observation data; the OPT file corresponding to the parameter information and the GNSS observation data is determined, and the GNSS carrier phase observation value of the target ground-based dual-antenna GNSS-R is obtained, and a three-difference observation equation is constructed through the OPT file, the GNSS carrier phase observation value and the satellite pair information, so as to calculate the ground height change in the target area to be monitored based on the three-difference observation equation. The present application can continuously monitor a specified ground position and area by designing the angle between the parts and the vertical direction and the height of the bracket, which is conducive to coping with more monitoring environments.

[0095] Secondly, a dual-antenna GNSS-R ground height change monitoring device proposed in an embodiment of the present application is described with reference to the accompanying drawings.

[0096] Fig. 9 It is a block diagram of a dual-antenna GNSS-R ground height change monitoring device according to an embodiment of the present application.

[0097] like Fig. 9 As shown, the dual-antenna GNSS-R ground height change monitoring device 10 includes: an adjustment module 100 , a screening module 200 and a monitoring module 300 .

[0098] Among them, the adjustment module 100 is used to obtain the location information and area information of the target area to be monitored, and adjust the downward antenna tilt angle and the bracket height of the target ground-based dual-antenna GNSS-R according to the location information and area information, so as to control the target area to be monitored to be within the Fresnel reflection area of ​​the target ground-based dual-antenna GNSS-R.

[0099] The screening module 200 is used to collect parameter information of the target ground-based dual-antenna GNSS-R when the target area to be monitored is in the Fresnel reflection area of ​​the target ground-based dual-antenna GNSS-R, collect GNSS observation data of the target ground-based dual-antenna GNSS-R, and perform quality screening on the GNSS observation data to obtain satellite pair information corresponding to the GNSS observation data.

[0100] The monitoring module 300 is used to determine the OPT file corresponding to the parameter information and GNSS observation data, and obtain the GNSS carrier phase observation value of the target ground-based dual-antenna GNSS-R, and construct a three-difference observation equation through the OPT file, GNSS carrier phase observation value and satellite pair information to calculate the ground height change in the target monitoring area based on the three-difference observation equation.

[0101] Optionally, in one embodiment of the present application, the regulating module 100 includes: a building unit and an adjusting unit.

[0102] Among them, the construction unit is used to construct the angle-adjustable connecting parts and the adjustable height bracket between the direct antenna and the reflective antenna in the target ground-based dual-antenna GNSS-R.

[0103] The adjustment unit is used to adjust the angle-adjustable connecting parts and the adjustable height bracket according to the position information and the area information, so as to continuously adjust the downward-looking antenna inclination angle and the bracket height of the target ground-based dual-antenna GNSS-R until the target area to be monitored is within the Fresnel reflection area of ​​the target ground-based dual-antenna GNSS-R.

[0104] Optionally, in one embodiment of the present application, the screening module 200 includes: a conversion unit, a first determination unit and a generation unit.

[0105] The conversion unit is used to convert the GNSS observation data of the target ground-based dual-antenna GNSS-R into a RINEX format to generate target observation data, wherein the target observation data includes direct antenna observation data and reflection antenna observation data.

[0106] The first determination unit is used to respectively determine the satellite zenith map, signal-to-noise ratio map and cycle slip occurrence information corresponding to the direct antenna observation data and the reflection antenna observation data, and perform quality screening processing on the target observation data according to the satellite zenith map, signal-to-noise ratio map and cycle slip occurrence information to generate at least one target satellite information.

[0107] A generating unit is used to generate satellite pair information based on at least one target satellite information and a satellite zenith map.

[0108] Optionally, in one embodiment of the present application, the monitoring module 300 includes: a relative positioning unit, a first acquisition unit, a second determination unit, a second acquisition unit, a fusion unit, an execution unit and an evaluation unit.

[0109] The relative positioning unit is used to relatively position the ground symmetrical points of the direct antenna and the reflective antenna to obtain the distance between the direct antenna and the reflective antenna at the ground symmetrical points in the north direction.

[0110] The first acquisition unit is used to acquire the altitude angle of the target ground-based dual-antenna GNSS-R, the antenna phase center spacing between the direct antenna and the reflection antenna, the horizontal projection length of the antenna phase center spacing, and the vertical distance from the ground to the antenna phase center of the reflection receiver of the target ground-based dual-antenna GNSS-R based on the OPT file, the GNSS carrier phase observation value and the satellite pair information.

[0111] The second determination unit is used to construct a geometric model of the signal propagation path of the target ground-based dual-antenna GNSS-R according to the altitude angle, horizontal projection length, antenna phase center spacing, vertical distance, the distance in the north direction between the direct antenna and the reflecting antenna at the symmetrical point on the ground and the preset cGNSS-R height measurement geometry.

[0112] The second acquisition unit is used to acquire the frequency band wavelength of the target satellite at the target time, the phase observation of the reflection receiver and the direct receiver of the target satellite, the clock difference between the reflection receiver and the direct receiver of the target satellite, and the ambiguity between the reflection receiver and the direct receiver of the target satellite and the phase observation based on the satellite pair information.

[0113] The fusion unit is used to determine the single-difference observation equation of the signal propagation path of the target satellite according to the frequency band wavelength, phase observation, clock difference and ambiguity, and to fuse the geometric model and the single-difference observation equation to establish the GNSS-R altimetry model.

[0114] The execution unit is used to establish three-difference observation equations based on the GNSS-R altimetry model, and perform difference operations between adjacent epochs through the three-difference observation equations to obtain the ground height change corresponding to each epoch.

[0115] Optionally, in one embodiment of the present application, the dual-antenna GNSS-R ground height change monitoring device 10 of the embodiment of the present application further includes: a drawing module and an evaluation module.

[0116] Among them, the drawing module is used to draw a corresponding scatter plot according to the ground height change amount corresponding to each epoch after calculating the ground height change amount in the target monitoring area.

[0117] The evaluation module is used to calculate the standard deviation and root mean square error of the scatter plot, so as to evaluate the monitoring performance of the target monitored area through the standard deviation and root mean square error products.

[0118] Optionally, in one embodiment of the present application, the mathematical expression of the geometric model is:

[0119]

[0120] Among them, ρ r represents the reflected signal path length of the reflecting antenna; ρ drepresents the direct signal path length of the direct antenna; h represents the vertical distance from the ground to the antenna phase center of the reflector receiver of the target ground-based dual-antenna GNSS-R; d represents the antenna phase center spacing between the direct antenna and the reflector antenna; θ represents the altitude angle of the target ground-based dual-antenna GNSS-R; n represents the distance in the north direction between the direct antenna and the reflector antenna at the symmetrical point on the ground; d1 represents the horizontal projection length of the antenna phase center spacing.

[0121] It should be noted that the aforementioned explanation of the dual-antenna GNSS-R ground height change monitoring method embodiment is also applicable to the dual-antenna GNSS-R ground height change monitoring device of this embodiment, and will not be repeated here.

[0122] According to the dual-antenna GNSS-R ground height change monitoring device proposed in the embodiment of the present application, it includes an adjustment module, which is used to obtain position information and area information of the target area to be monitored, and adjust the downward antenna tilt angle and the bracket height of the target ground-based dual-antenna GNSS-R according to the position information and area information to control the target area to be monitored to be within the Fresnel reflection area of ​​the target ground-based dual-antenna GNSS-R; a screening module, which is used to collect parameter information of the target ground-based dual-antenna GNSS-R when the target area to be monitored is in the Fresnel reflection area of ​​the target ground-based dual-antenna GNSS-R, and collect GNSS observation data of the target ground-based dual-antenna GNSS-R, and perform quality screening processing on the GNSS observation data to obtain satellite pair information corresponding to the GNSS observation data; a monitoring module, which is used to determine the OPT file corresponding to the parameter information and the GNSS observation data, and obtain the GNSS carrier phase observation value of the target ground-based dual-antenna GNSS-R, and construct a three-difference observation equation through the OPT file, the GNSS carrier phase observation value and the satellite pair information, so as to calculate the ground height change in the target area to be monitored based on the three-difference observation equation. The present application can continuously monitor a specified ground position and area by designing the angle between the parts and the vertical direction and the height of the bracket, which is conducive to coping with more monitoring environments.

[0123] Fig.10 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. The electronic device may include:

[0124] A memory 1001 , a processor 1002 , and a computer program stored in the memory 1001 and executable on the processor 1002 .

[0125] When the processor 1002 executes the program, the dual-antenna GNSS-R ground height change monitoring method provided in the above embodiment is implemented.

[0126] Furthermore, the electronic device further comprises:

[0127] The communication interface 1003 is used for communication between the memory 1001 and the processor 1002 .

[0128] The memory 1001 is used to store computer programs that can be executed on the processor 1002 .

[0129] The memory 1001 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0130] If the memory 1001, the processor 1002 and the communication interface 1003 are implemented independently, the communication interface 1003, the memory 1001 and the processor 1002 can be connected to each other through a bus and communicate with each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component (PCI) bus or an Extended Industry Standard Architecture (EISA) bus. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Fig.10 Only one thick line is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0131] Optionally, in a specific implementation, if the memory 1001, the processor 1002 and the communication interface 1003 are integrated on a chip, the memory 1001, the processor 1002 and the communication interface 1003 can communicate with each other through an internal interface.

[0132] The processor 1002 may be a central processing unit (CPU), or an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application.

[0133] An embodiment of the present application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the above dual-antenna GNSS-R ground height change monitoring method.

[0134] An embodiment of the present application also provides a computer program product, including a computer program, which, when executed, is used to implement the above-mentioned dual-antenna GNSS-R ground height change monitoring method.

[0135] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or N embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0136] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, "N" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0137] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or N executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

[0138] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purpose of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or N wirings (electronic devices), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), a fiber optic device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways as necessary and then storing it in a computer memory.

[0139] It should be understood that the various parts of the present application can be implemented by hardware, software, firmware or a combination thereof. In the above embodiment, the N steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. If implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0140] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

[0141] In addition, each functional unit in each embodiment of the present application may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0142] The storage medium mentioned above may be a read-only memory, a magnetic disk or an optical disk, etc. Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the present application. A person of ordinary skill in the art may change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A dual-antenna GNSS-R ground height change monitoring method, characterized in that: The following steps are involved: Acquire the location information and area information of the target area to be monitored, and adjust the downward-looking antenna tilt angle and the bracket height of the target ground-based dual-antenna GNSS-R according to the location information and the area information, so as to control the target area to be monitored to be within the Fresnel reflection area of ​​the target ground-based dual-antenna GNSS-R; Collecting parameter information of the target ground-based dual-antenna GNSS-R when the target area to be monitored is in the Fresnel reflection area of ​​the target ground-based dual-antenna GNSS-R, collecting GNSS observation data of the target ground-based dual-antenna GNSS-R, and performing quality screening on the GNSS observation data to obtain satellite pair information corresponding to the GNSS observation data; Determine the OPT file corresponding to the parameter information and the GNSS observation data, and obtain the GNSS carrier phase observation value of the target ground-based dual-antenna GNSS-R, and construct a three-difference observation equation through the OPT file, the GNSS carrier phase observation value and the satellite pair information to calculate the ground height change in the target monitored area based on the three-difference observation equation.

2. The method according to claim 1, characterized in that The step of adjusting the downward-looking antenna tilt angle and the bracket height of the target ground-based dual-antenna GNSS-R according to the position information and the area information to control the target area to be monitored to be within the Fresnel reflection area of ​​the target ground-based dual-antenna GNSS-R includes: Constructing an angle-adjustable connecting part and an adjustable height bracket between the direct antenna and the reflector antenna in the target ground-based dual-antenna GNSS-R; The angle-adjustable connecting part and the adjustable height bracket are adjusted according to the position information and the area information to continuously adjust the downward-looking antenna inclination angle and the bracket height of the target ground-based dual-antenna GNSS-R until the target area to be monitored is within the Fresnel reflection area of ​​the target ground-based dual-antenna GNSS-R.

3. The method according to claim 2, characterized in that The collecting of the GNSS observation data of the target ground-based dual-antenna GNSS-R and performing quality screening on the GNSS observation data to obtain satellite pair information corresponding to the GNSS observation data includes: Performing RINEX format conversion on the GNSS observation data of the target ground-based dual-antenna GNSS-R to generate target observation data, wherein the target observation data includes direct antenna observation data and reflection antenna observation data; Respectively determining a satellite zenith map, a signal-to-noise ratio map, and cycle slip occurrence information corresponding to the direct antenna observation data and the reflection antenna observation data, and performing quality screening processing on the target observation data according to the satellite zenith map, the signal-to-noise ratio map, and the cycle slip occurrence information to generate at least one target satellite information; The satellite pair information is generated based on the at least one target satellite information and the satellite zenith map.

4. The method according to claim 3, characterized in that The constructing of a three-difference observation equation through the OPT file, the GNSS carrier phase observation value and the satellite pair information to calculate the ground height change in the target monitoring area based on the three-difference observation equation includes: Relative positioning of the ground symmetrical points of the direct antenna and the reflective antenna to obtain the distance between the direct antenna and the reflective antenna at the ground symmetrical points in the north direction; Based on the OPT file, the GNSS carrier phase observation value and the satellite pair information, obtain the altitude angle of the target ground-based dual-antenna GNSS-R, the antenna phase center spacing between the direct antenna and the reflector antenna, the horizontal projection length of the antenna phase center spacing, and the vertical distance from the ground to the antenna phase center of the reflector receiver of the target ground-based dual-antenna GNSS-R; Constructing a geometric model of the signal propagation path of the target ground-based dual-antenna GNSS-R according to the altitude angle, the horizontal projection length, the antenna phase center spacing, the vertical distance, the distance between the direct antenna and the reflector antenna at the symmetrical point on the ground in the north direction, and a preset cGNSS-R altimetry geometric relationship; Based on the satellite pair information, the frequency band wavelength of the target satellite at the target time, the phase observation of the reflection receiver and the direct receiver of the target satellite, the clock difference between the reflection receiver and the direct receiver of the target satellite, and the ambiguity between the reflection receiver and the direct receiver of the target satellite and the phase observation are obtained; Determine a single-difference observation equation of a signal propagation path of the target satellite according to the frequency band wavelength, the phase observation amount, the clock difference value and the ambiguity, and fuse the geometric model and the single-difference observation equation to establish a GNSS-R altimetry model; Based on the GNSS-R altimetry model, the three-difference observation equation is established, and the difference operation of adjacent epochs is performed through the three-difference observation equation to obtain the ground height change corresponding to each epoch.

5. The method according to claim 4, characterized in that After calculating the ground height change in the target area to be monitored, the method further includes: Draw a corresponding scatter plot according to the ground height change corresponding to each epoch; The standard deviation and the root mean square error of the scatter plot are calculated to evaluate the monitoring performance of the target monitored area through the standard deviation and the root mean square error.

6. The method according to claim 4, characterized in that The mathematical expression of the geometric model is: Among them, ρ r represents the reflection signal path length of the reflection antenna; ρ d represents the direct signal path length of the direct antenna; h represents the vertical distance from the ground to the antenna phase center of the reflection receiver of the target ground-based dual-antenna GNSS-R; d represents the antenna phase center spacing between the direct antenna and the reflection antenna; θ represents the altitude angle of the target ground-based dual-antenna GNSS-R; n represents the distance between the direct antenna and the reflection antenna in the north direction at the symmetrical point on the ground; d1 represents the horizontal projection length of the antenna phase center spacing.

7. A dual-antenna GNSS-R ground height change monitoring device, characterized in that: include: An adjustment module is used to obtain the position information and area information of the target area to be monitored, and adjust the downward-looking antenna tilt angle and the bracket height of the target ground-based dual-antenna GNSS-R according to the position information and the area information, so as to control the target area to be monitored to be within the Fresnel reflection area of ​​the target ground-based dual-antenna GNSS-R; a screening module, for collecting parameter information of the target ground-based dual-antenna GNSS-R when the target area to be monitored is in the Fresnel reflection area of ​​the target ground-based dual-antenna GNSS-R, collecting GNSS observation data of the target ground-based dual-antenna GNSS-R, and performing quality screening processing on the GNSS observation data to obtain satellite pair information corresponding to the GNSS observation data; A monitoring module is used to determine the OPT file corresponding to the parameter information and the GNSS observation data, and obtain the GNSS carrier phase observation value of the target ground-based dual-antenna GNSS-R, and construct a three-difference observation equation through the OPT file, the GNSS carrier phase observation value and the satellite pair information, so as to calculate the ground height change in the target monitoring area based on the three-difference observation equation.

8. An electronic device, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the dual-antenna GNSS-R ground height change monitoring method as described in any one of claims 1 to 6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: The program is executed by a processor to implement the dual-antenna GNSS-R ground height change monitoring method as described in any one of claims 1 to 6.

10. A computer program product, comprising a computer program, characterized in that The computer program is executed to implement the dual-antenna GNSS-R ground height change monitoring method as described in any one of claims 1-6.

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