Rapid calibration method, device and electronic equipment for GNSS-R sea surface measurement height

Abstract

The embodiment of the present application provides a method, device and electronic device for rapid calibration of GNSS-R sea surface measurement height, which relates to the field of satellites. The method includes: obtaining height measurement data, which all come from the same satellite receiving platform; determining at least one calibration comparison point based on altimeter measurement data and GNSS-R measurement data, and the calibration comparison point meets the preset time and space requirements; performing error correction on the measurement data of the calibration comparison point to obtain the corrected measurement data of the calibration comparison point; calculating based on the corrected measurement height of the GNSS-R mirror reflection point and the corrected measurement height of the altimeter observation point to obtain measurement deviation data; performing linear interpolation on the measurement deviation data according to different angles of the GNSS-R mirror reflection point in the calibration comparison point to obtain the calibration result. Through the above method, rapid on-orbit calibration of GNSS-R sea surface height is achieved, and at the same time, the comparison point error during calibration is effectively reduced, and accurate on-orbit calibration of different GNSS-R sea surface height calibration accuracies is further achieved.

Description

Technical Field

[0001] The present application relates to the field of satellites, and in particular to a method, device and electronic equipment for rapid calibration of GNSS-R sea surface height measurement. Background Art

[0002] GNSS Reflectometry (GNSS-R) altimetry technology is a new altimetry technology developed since the 1990s. This technology simultaneously receives GNSS direct signals and sea surface reflected signals, accurately measures the spatial propagation delay difference between GNSS direct signals and sea surface reflected signals, and inverts the sea surface height at the mirror reflection point of the mirror GNSS-R.

[0003] The GNSS-R altimeter receiver in orbit has a systematic deviation between the altimeter result and the true altitude due to a variety of complex reasons such as instrument hardware delay and inaccurate antenna phase center correction. This system deviation may drift due to instrument aging as the working time increases. Therefore, in order to timely discover and correct the above system observation errors and ensure that the onboard GNSS-R sea surface altimeter meets the design index requirements and the consistency and reliability of the long-term observation data accuracy, it is necessary to calibrate the measurement data. The traditional calibration method is generally to calibrate the GNSS-R sea surface altitude through the ocean calibration field.

[0004] However, the accuracy of the traditional ocean calibration field is too low due to its large spatial range, long delay, and overly complex data within the calibration field, such as observation point angle information, which in turn leads to inaccurate results in sea surface height measurement. Summary of the invention

[0005] The embodiments of the present application provide a method, device and electronic device for rapid calibration of GNSS-R sea surface height measurement, which can realize precise on-orbit calibration of GNSS-R sea surface height measurement, thereby improving the accuracy of sea surface height measurement.

[0006] In a first aspect, an embodiment of the present application provides a method for rapid calibration of GNSS-R sea surface measurement height, the method comprising:

[0007] Acquire height measurement data of the target sea surface, wherein the height measurement data includes altimeter measurement data and GNSS-R measurement data, and the altimeter measurement data and GNSS-R measurement data are both derived from the same satellite receiving platform;

[0008] Determine at least one calibration comparison point according to the altimeter measurement data and the GNSS-R measurement data, wherein an altimeter observation point and a GNSS-R mirror reflection point together constitute a calibration comparison point, and the calibration comparison point meets the preset time and space requirements;

[0009] Performing error correction on the measurement data of the calibration comparison point to obtain corrected measurement data of the calibration comparison point, wherein the corrected measurement data includes a corrected measurement height of a GNSS-R mirror reflection point and a corrected measurement height of an altimeter observation point;

[0010] Calculating based on the GNSS-R mirror reflection point corrected measurement height and the altimeter observation point corrected measurement height, obtaining the measurement deviation data of the calibration comparison point;

[0011] The measurement deviation data is linearly interpolated according to different angles of the GNSS-R mirror reflection point in the calibration comparison point to obtain a calibration result.

[0012] Optionally, determining at least one calibration comparison point according to the altimeter measurement data and the GNSS-R measurement data comprises:

[0013] Screening measurement data that meets preset quality requirements from the altimeter measurement data and the GNSS-R measurement data to obtain candidate altimeter measurement data and candidate GNSS-R measurement data;

[0014] According to preset time and space requirements, altimeter observation points and GNSS-R mirror reflection points for calibration comparison are selected from the altimeter measurement data and the GNSS-R measurement data to obtain at least one calibration comparison point.

[0015] Optionally, the time and space requirements include at least one of the following:

[0016] At a calibration comparison point, the difference between the acquisition time of the measurement data of the GNSS-R specular reflection point and the acquisition time of the measurement data of the altimeter observation point is less than a first preset time length;

[0017] At a calibration comparison point, the distance between the GNSS-R mirror reflection point and the altimeter observation point is less than half of the cross-track spatial resolution of the track where the GNSS-R mirror reflection point is located;

[0018] In one calibration point, the GNSS-R mirror reflection point and the altimeter observation point belong to the same ascending orbit or the GNSS-R mirror reflection point and the altimeter observation point belong to the same descending orbit.

[0019] Optionally, after screening the GNSS-R mirror reflection points and the altimeter observation points for calibration comparison in the altimeter measurement data and the GNSS-R measurement data according to preset time and space requirements, for the same calibration comparison point, determining at least one calibration comparison point according to the altimeter measurement data and the GNSS-R measurement data further includes:

[0020] Taking the GNSS-R mirror reflection point in the calibration comparison point as the center point, based on the along-track spatial resolution of the track where the GNSS-R mirror reflection point in the calibration comparison point is located and the cross-track spatial resolution of the track where the GNSS-R mirror reflection point is located, construct a first equivalent observation area of ​​the calibration comparison point;

[0021] Taking the GNSS-R mirror reflection point in the calibration comparison point as the center point, based on the along-track spatial resolution of the track where the GNSS-R mirror reflection point in the calibration comparison point is located and the cross-track spatial resolution of the track where the altimeter observation point is located, construct a second equivalent observation area of ​​the calibration comparison point;

[0022] Taking the altimeter observation point in the calibration comparison point as the center point, based on the along-track spatial resolution of the track where the GNSS-R mirror reflection point in the calibration comparison point is located and the cross-track spatial resolution of the track where the GNSS-R mirror reflection point is located, construct a third equivalent observation area of ​​the calibration comparison point;

[0023] Taking the altimeter observation point in the calibration comparison point as the center point, based on the along-track spatial resolution of the track where the GNSS-R mirror reflection point in the calibration comparison point is located and the cross-track spatial resolution of the track where the altimeter observation point is located, construct a fourth equivalent observation area of ​​the calibration comparison point;

[0024] Calculating the average geoid heights in the first equivalent observation area and the second equivalent observation area respectively, and calculating the difference, to obtain the difference between the first geoid heights of the first equivalent observation area and the second equivalent observation area;

[0025] Calculating the average geoid heights in the third equivalent observation area and the fourth equivalent observation area respectively, and calculating the difference, to obtain the difference in the second geoid height between the third equivalent observation area and the fourth equivalent observation area;

[0026] If the difference between the first geoid height and the difference between the second geoid height are both less than a preset accuracy, the calibration comparison point is retained.

[0027] Optionally, the corrected measurement data includes a GNSS-R mirror reflection point corrected measurement height and an altimeter observation point corrected measurement height, and the error correction of the measurement data of the calibration comparison point to obtain the corrected measurement data of the calibration comparison point includes:

[0028] Performing error correction on the measurement data of the GNSS-R mirror reflection point in the calibration comparison point to obtain the corrected measurement height of the GNSS-R mirror reflection point;

[0029] The measurement data of the altimeter observation point is combined with the measurement data of other altimeter observation points on the orbit where the altimeter observation point is located, and error correction is performed on the measurement data of the altimeter observation point to obtain the corrected measurement height of the altimeter observation point.

[0030] Optionally, the error correction of the measurement data of the GNSS-R mirror reflection point in the calibration comparison point includes at least one of the following:

[0031] Performing tropospheric delay correction on the measurement data of the GNSS-R mirror reflection point in the calibration comparison point;

[0032] Performing sea surface electromagnetic deviation correction on the measurement data of the GNSS-R mirror reflection point in the calibration comparison point;

[0033] Performing ionospheric delay correction on the measurement data of the GNSS-R mirror reflection point in the calibration comparison point;

[0034] Performing solid tide correction on the measurement data of the GNSS-R mirror reflection point in the calibration comparison point;

[0035] Performing polar tide correction on the measurement data of the GNSS-R mirror reflection point in the calibration comparison point;

[0036] The measurement data of the GNSS-R mirror reflection point in the calibration comparison point is corrected for ocean tides.

[0037] Optionally, the combining measurement data of other altimeter observation points on the orbit where the altimeter observation point is located to perform error correction on the measurement data of the altimeter observation point includes:

[0038] Performing a first error correction on the measurement data of the altimeter observation point and the measurement data of the other altimeter observation points to obtain a first corrected height of the altimeter observation point and a second corrected height of the other altimeter observation points, wherein the first error correction includes at least one of a tropospheric delay correction, a sea surface electromagnetic deviation correction, an ionospheric delay correction, a solid tide correction, a polar tide correction, and an ocean tide correction;

[0039] Performing absolute calibration processing on the first calibrated height and the second calibrated height to obtain a third calibrated height of the altimeter observation point and a fourth calibrated height of the other altimeter observation points, respectively;

[0040] The third corrected height and the fourth corrected height are smoothed according to the along-track spatial resolution of the GNSS-R mirror reflection point to obtain the corrected measurement height of the altimeter observation point.

[0041] Optionally, the accuracy of the smoothing process is the same as the along-track spatial resolution of the GNSS-R mirror reflection point corresponding to the altimeter observation point, and the average position of the other altimeter observation points is the same as the position of the altimeter observation point.

[0042] Optionally, after smoothing the first corrected height and the second corrected height according to the along-track spatial resolution of the GNSS-R mirror reflection point, performing error correction on the measurement data of the altimeter observation point further comprises:

[0043] Performing geoid correction on the corrected measured height of the altimeter observation point to obtain a final corrected height of the altimeter observation point;

[0044] The calculating based on the GNSS-R mirror reflection point corrected measurement height and the altimeter observation point corrected measurement height to obtain the measurement deviation data of the calibration comparison point includes:

[0045] The measurement deviation data of the calibration comparison point is obtained by performing calculation based on the final corrected height of the altimeter observation point and the corrected measured height of the GNSS-R mirror reflection point.

[0046] Optionally, the correction amount of the geoid correction is the difference in geoid height between the GNSS-R mirror reflection point and the altimeter observation point in the calibration comparison point.

[0047] Optionally, performing linear interpolation on the measurement deviation data according to different angles of the GNSS-R mirror reflection points in the calibration comparison points to obtain a calibration result of the target sea surface includes:

[0048] Classifying the measurement deviation data according to different satellite systems to obtain measurement deviation data of different satellite systems;

[0049] Two-dimensional linear interpolation is performed on the measurement deviation data of the different satellite systems according to the elevation angle and azimuth angle of the GNSS-R mirror reflection point in the calibration comparison point to obtain calibration results of the different satellite systems.

[0050] Optionally, after obtaining the calibration result, the method further includes:

[0051] Acquire first sea surface height measurement data, where the first sea surface height measurement data is measured based on a sea surface inversion signal from a satellite, and the first sea surface height measurement data includes an elevation angle and an azimuth angle of a measurement point;

[0052] The first sea level height measurement data is corrected by querying a corresponding correction deviation in the calibration result based on the elevation angle and the azimuth angle of the measurement point.

[0053] In a second aspect, an embodiment of the present application provides a GNSS-R sea surface measurement height rapid calibration device, the device comprising:

[0054] A data acquisition module is used to acquire height measurement data of a target sea surface, wherein the height measurement data includes altimeter measurement data and GNSS-R measurement data, and both the altimeter measurement data and the GNSS-R measurement data are derived from the same satellite receiving platform;

[0055] A calibration comparison point determination module, used to determine at least one calibration comparison point according to the altimeter measurement data and the GNSS-R measurement data, wherein an altimeter observation point and a GNSS-R mirror reflection point together constitute a calibration comparison point, and the calibration comparison point meets the preset time and space requirements;

[0056] An error correction module is used to perform error correction on the measurement data of the calibration comparison point to obtain corrected measurement data of the calibration comparison point, wherein the corrected measurement data includes a corrected measurement height of a GNSS-R mirror reflection point and a corrected measurement height of an altimeter observation point;

[0057] A measurement deviation calculation module, used to calculate based on the GNSS-R mirror reflection point correction measurement height and the altimeter observation point correction measurement height to obtain the measurement deviation data of the calibration comparison point;

[0058] The interpolation module is used to perform linear interpolation on the measurement deviation data according to different angles of the GNSS-R mirror reflection points in the calibration comparison points to obtain a calibration result.

[0059] In a third aspect, an embodiment of the present application provides an electronic device, comprising: a processor and a memory, wherein the processor executes a computer program stored in the memory to implement the rapid calibration method of the GNSS-R sea surface measurement height as described in the first aspect.

[0060] In a fourth aspect, an embodiment of the present application provides a readable storage medium, wherein the readable storage medium stores computer instructions, and when the computer instructions are executed by a processor, the method for rapid calibration of GNSS-R sea surface measurement height as described in the first aspect is implemented.

[0061] The embodiments of the present application include the following advantages:

[0062] In summary, the embodiment of the present application provides a fast calibration method for GNSS-R sea surface measurement height. After obtaining the height measurement data of the target sea surface, at least one calibration comparison point is determined according to the altimeter measurement data and the GNSS-R measurement data, and the measurement data of the calibration comparison point is error corrected to obtain the GNSS-R mirror reflection point corrected measurement height and the altimeter observation point corrected measurement height of the calibration comparison point, and then based on the GNSS-R mirror reflection point corrected measurement height and the altimeter observation point corrected measurement height, calculation is performed to obtain the measurement deviation data of the calibration comparison point, and finally the measurement deviation data is linearly interpolated according to the different angles of the GNSS-R mirror reflection point in the calibration comparison point to obtain the calibration result. The calibration method based on the same platform realizes the rapid on-orbit calibration of GNSS-R sea surface height. At the same time, by adjusting the time matching and space matching thresholds between GNSS-R sea surface height and altimeter sea surface height observations, the comparison point error during the calibration of GNSS-R satellite inverted sea surface height is effectively reduced, and accurate on-orbit calibration of different GNSS-R sea surface height calibration accuracies is realized, thereby improving the accuracy of sponge height measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the description of the embodiments of the present application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0064] Figure 1 A flowchart showing an embodiment of a method for rapid calibration of GNSS-R sea surface height measurement of the present application is shown;

[0065] Figure 2 A distribution diagram of GNSS-R mirror reflection points and altimeter observation points under the same satellite platform in an embodiment of the present application is shown;

[0066] Figure 3 A distribution diagram of calibration comparison points according to an embodiment of the present application is shown;

[0067] Figure 4 A distribution diagram of a first equivalent observation area and a second equivalent observation area according to an embodiment of the present application is shown;

[0068] Figure 5 A distribution diagram of a third equivalent observation area and a fourth equivalent observation area according to an embodiment of the present application is shown;

[0069] Figure 6 A calibration point distribution diagram that meets the pairing requirements of an embodiment of the present application is shown;

[0070] Figure 7 A graph showing the variation of the average deviation of the sea surface height inverted by a GNSS-R system according to an embodiment of the present application with the number of calibration points;

[0071] Figure 8 A structural block diagram of an embodiment of a GNSS-R sea surface height measurement rapid calibration device of the present application is shown;

[0072] Fig. 9 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0073] The following will clearly and completely describe the technical solutions in the embodiments of the present application in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application. In addition, it should be noted that the various data-related processes in the embodiments of the present application are all carried out in compliance with the corresponding data protection laws and policies of the country of location, and with the authorization given by the owner of the corresponding device.

[0074] Reference Figure 1 , shows an embodiment of a rapid calibration method for GNSS-R sea surface measurement height of the present application, the method comprising:

[0075] Step 101: Acquire height measurement data of a target sea surface, wherein the height measurement data includes altimeter measurement data and GNSS-R measurement data, and both the altimeter measurement data and the GNSS-R measurement data are derived from the same satellite receiving platform.

[0076] The target sea surface refers to the sea surface where the sea surface height measurement is required.

[0077] In the measurement of sea surface height, whether it is the technology based on GNSS-R reflected signal inversion of sea surface height or the single-satellite sea surface height measurement technology measured by altimeter, there are errors, so the measured data needs to be calibrated. In addition, because the two sea surface height measurement technologies have their own limitations, specifically, the sea surface height inversion of GNSS-R reflected signal may not be affected by the satellite orbit position. By selecting different signal receiving low-orbit satellites, the sea surface height is measured at multiple different observation points on the sea surface at the same time. The speed of sea surface height measurement is faster, but relatively speaking, the accuracy is not as good as the altimeter measurement technology. However, the altimeter measurement technology is affected by the satellite orbit position and can only measure the sea surface height of the sub-satellite point. The measurement speed is too slow to ensure the reliability of the sea surface height measurement data. Based on the above problems, in the embodiments of the present application, the respective advantages of the GNSS-R reflected signal inversion sea surface height technology and the altimeter measurement technology are combined, and it is proposed to use the following method: Figure 1 The method shown is to compare and process altimeter measurement data and GNSS-R measurement data under the same GNSS-R satellite platform to obtain sea surface height calibration results.

[0078] Reference Figure 2 A distribution diagram of the GNSS-R mirror reflection points and altimeter observation point trajectories under the same satellite platform of an embodiment of the present application is shown, and the same satellite platform means that both the altimeter measurement data and the GNSS-R measurement data are derived from the same satellite signal receiving platform. Based on the above two sea surface height measurement technologies, in an embodiment of the present application, the observation points are correspondingly divided into GNSS-R mirror reflection points and altimeter observation points. The altimeter observation point is also called a sub-satellite point, in which the line connecting the satellite that transmits the direct signal and the altimeter observation point is perpendicular to the sea level where the altimeter observation point is located. And because the satellite is in a continuous motion process, the GNSS-R mirror reflection points and altimeter observation points obtained by the same GNSS-R satellite platform will also form their own altimeter observation point trajectories and mirror GNSS-R mirror reflection point trajectories accordingly.

[0079] Therefore, the historical altimeter data includes the altimeter measurement data and GNSS-R measurement data measured under the same GNSS-R satellite signal receiving platform, which may include but are not limited to the sea surface measurement height of the altimeter observation point and the GNSS-R mirror reflection point, location information such as longitude and latitude, quality code of the altimeter data, GNSS-R mirror reflection point angle information, etc., so as to be used for subsequent screening of observation points and data processing.

[0080] The historical altimetry data can be obtained through public measurement data or sea surface altimetry product measurement, and this application does not limit this. Among them, the quality code of the altimetry data refers to the preliminary evaluation of the quality of the altimetry result by the sea surface altimetry product when the sea surface altimetry product is used to measure the height data of the observation point in the target sea surface. For example, a good quality code indicates that the altimetry result is relatively accurate. This example is only used to explain the quality code and is not a limitation on the quality code.

[0081] Step 102: Determine at least one calibration comparison point according to the altimeter measurement data and the GNSS-R measurement data.

[0082] Among them, an altimeter observation point and a GNSS-R mirror reflection point together constitute a calibration comparison point. In the embodiment of the present application, the calibration comparison point is used to determine the error between the altimeter height measurement and the height measurement data obtained by GNSS-R inversion, and obtain the calibration results between different sea surface height measurement methods.

[0083] The historical height measurement data of the target sea surface include multiple altimeter measurement data and GNSS-R measurement data. However, taking into account the sea surface height strategies implemented by multiple altimeter observation points and GNSS-R mirror reflection points at different times and under different circumstances, it is necessary to determine at least one calibration comparison point among multiple GNSS-R mirror reflection points and altimeter observation points according to preset time and space requirements to calculate the calibration result. For example, in one calibration comparison point, the difference between the acquisition time of the measurement data of the GNSS-R mirror reflection point and the acquisition time of the measurement data of the altimeter observation point is less than a first preset time length; in one calibration comparison point, the distance between the GNSS-R mirror reflection point and the altimeter observation point is less than half of the cross-track spatial resolution of the track where the GNSS-R mirror reflection point is located. The preset time and space requirements can be adjusted according to actual conditions, and this application does not limit this.

[0084] In an optional embodiment of the present application, determining at least one calibration comparison point according to the altimeter measurement data and the GNSS-R measurement data in step 102 may include at least one of the following:

[0085] Step S100, screening measurement data that meets preset quality requirements from the altimeter measurement data and the GNSS-R measurement data to obtain candidate altimeter measurement data and candidate GNSS-R measurement data;

[0086] Step S101: selecting altimeter observation points and GNSS-R mirror reflection points for calibration comparison in the altimeter measurement data and the GNSS-R measurement data according to preset time and space requirements to obtain at least one calibration comparison point.

[0087] The preset quality requirement refers to the measurement results with relatively high quality in the historical measurement data or with relatively small errors given by the sea surface height measurement product. For example, for step S100, altimeter observation points and GNSS-R mirror reflection points with good quality codes can be screened out from the measurement data obtained from the sea surface height product as candidate altimeter measurement data and candidate GNSS-R measurement data.

[0088] Of course, for a GNSS-R mirror reflection point and altimeter observation point in a calibration comparison point, the measurement time and the position relationship of the point must also meet certain conditions, namely the preset time and space requirements. In this case, the distance between the two points can be ignored relative to the satellite altitude and sea level, and the change in sea level within a certain period of time is very small, which can also be ignored relative to the sea level. Therefore, the GNSS-R mirror reflection point and comparison point that meet the preset time and space requirements can be regarded as one point, namely the calibration comparison point.

[0089] Optionally, the time and space requirements include any one of the following:

[0090] At a calibration comparison point, the difference between the acquisition time of the measurement data of the GNSS-R specular reflection point and the acquisition time of the measurement data of the altimeter observation point is less than a first preset time length;

[0091] At a calibration comparison point, the distance between the GNSS-R mirror reflection point and the altimeter observation point is less than half of the cross-track spatial resolution of the track where the GNSS-R mirror reflection point is located;

[0092] In one calibration point, the GNSS-R mirror reflection point and the altimeter observation point belong to the same ascending orbit or the GNSS-R mirror reflection point and the altimeter observation point belong to the same descending orbit.

[0093] Among them, the orbit of the GNSS-R mirror reflection point refers to the trajectory formed by the GNSS-R mirror reflection point on the sea surface when sea surface measurement is carried out under the same GNSS satellite platform, and the cross-track spatial resolution refers to the spatial resolution in a direction perpendicular to the orbit of a certain observation point and perpendicular to the sea level where the observation point is located. As an example, therefore, the cross-track spatial resolution of the orbit of the GNSS-R mirror reflection point refers to the spatial resolution in a direction perpendicular to the orbit of the GNSS-R mirror reflection point and perpendicular to the sea level where the GNSS-R mirror reflection point is located. In simple terms, the cross-track direction is the direction perpendicular to the GNSS-R mirror reflection point. In the actual sea surface height calibration process, this application does not make strict limitations on this, and the actual calibration effect is used as the adjustment standard.

[0094] Corresponding to the satellite's orbit, the ascending orbit means that the extension direction of the orbit where the observation point is located is from south to north, and the descending orbit means that the extension direction of the orbit where the observation point is located is from north to south. The GNSS-R mirror reflection point and the altimeter observation point have the same orbit direction to avoid the influence of different changing trends of sea surface height in different latitude directions on the confirmation process of calibration comparison points.

[0095] Specifically, the sea surface height observation time at the GNSS-R mirror reflection point A can be used as the time reference for time matching, and the first preset time length can be determined to be 2 days, and the altimeter observation points within the time range of 2 days before and after the time reference can be deleted; the position of the GNSS-R mirror reflection point A can be used as the spatial reference for spatial matching, and the altimeter observation points whose distance to the reference point is less than 1 / 2 of the cross-track spatial resolution of the track where the GNSS-R mirror reflection point is located can be deleted; the altimeter observation point should be in the same track direction as the GNSS-R mirror reflection point, that is, be in the same ascending or descending orbit, and only the altimeter observation points whose time and distance are closest to the GNSS-R mirror reflection point are selected as comparison points.

[0096] As an example, refer to Figure 3 The distribution diagram of a calibration comparison point of an embodiment of the present application shown in the figure takes the sea level observation time at the GNSS-R mirror reflection point O1 as the time reference, performs time matching, and selects the altimeter observation points within a time range of 2 days before and after the time reference; takes the position of the GNSS-R mirror reflection point O1 as the spatial reference, performs spatial matching, and selects the altimeter observation points whose distance to the reference point is less than 1 / 2 of the GNSS-R cross-track spatial resolution; the altimeter observation point should be in the same track direction as the GNSS-R mirror reflection point, that is, in the same ascending or descending track, and only selects the altimeter observation points whose time and distance are closest to the GNSS-R mirror reflection point as comparison points, such as Figure 3 As shown in O2.

[0097] In this case, the influence of time on the sea surface height measurement results of the same point and the influence of the distance between the altimeter observation point and the GNSS-R mirror reflection point on the measurement results can be ignored, thereby reducing the complexity of the calibration operation while ensuring the accuracy of the calibration results.

[0098] In an optional embodiment of the present application, after selecting altimeter observation points and GNSS-R mirror reflection points for calibration comparison in the altimeter measurement data and the GNSS-R measurement data according to preset time and space requirements in step S101 to obtain at least one calibration comparison point, determining at least one calibration comparison point according to the altimeter measurement data and the GNSS-R measurement data in step 102 may also include:

[0099] Step S200, taking the GNSS-R mirror reflection point in the calibration comparison point as the center point, based on the along-track spatial resolution of the track where the GNSS-R mirror reflection point in the calibration comparison point is located and the cross-track spatial resolution of the track where the GNSS-R mirror reflection point is located, constructing a first equivalent observation area of ​​the calibration comparison point;

[0100] Step S201, taking the GNSS-R mirror reflection point in the calibration comparison point as the center point, based on the along-track spatial resolution of the track where the GNSS-R mirror reflection point in the calibration comparison point is located and the cross-track spatial resolution of the track where the altimeter observation point is located, constructing a second equivalent observation area of ​​the calibration comparison point;

[0101] Step S202: Taking the altimeter observation point in the calibration comparison point as the center point, based on the along-track spatial resolution of the track where the GNSS-R mirror reflection point in the calibration comparison point is located and the cross-track spatial resolution of the track where the GNSS-R mirror reflection point is located, construct a third equivalent observation area of ​​the calibration comparison point;

[0102] Step S203, taking the altimeter observation point in the calibration comparison point as the center point, based on the along-track spatial resolution of the track where the GNSS-R mirror reflection point in the calibration comparison point is located and the cross-track spatial resolution of the track where the altimeter observation point is located, constructing a fourth equivalent observation area of ​​the calibration comparison point;

[0103] Step S204, respectively calculating the average geoid heights in the first equivalent observation area and the second equivalent observation area, and calculating the difference to obtain the difference in the first geoid heights between the first equivalent observation area and the second equivalent observation area;

[0104] Step S205, respectively calculating the average geoid heights in the third equivalent observation area and the fourth equivalent observation area, and calculating the difference to obtain the difference in the second geoid height between the third equivalent observation area and the fourth equivalent observation area;

[0105] Step S206: If the difference between the first geoid height and the difference between the second geoid height are both less than a preset accuracy, retaining the calibration comparison point.

[0106] Among them, the geoid refers to the level surface that coincides with the mean sea level and extends to the interior of the continent. It is the reference surface for orthometric height. In the measurement work, the geoid is used as the basis. Corresponding to the cross-track spatial resolution mentioned above, the along-track spatial resolution refers to the spatial resolution of a certain observation point along the orbit where the observation point is located; the orbit where the altimeter observation point is located refers to the track formed by the altimeter observation point on the sea surface when the sea surface is measured under the same GNSS satellite platform. Therefore, the specific definitions of the cross-track and along-track directions in steps S200-S206 can be as follows:

[0107] The cross-track spatial resolution of the track where the GNSS-R mirror reflection point is located refers to the spatial resolution in the direction perpendicular to the track where the GNSS-R mirror reflection point is located and perpendicular to the sea level where the GNSS-R mirror reflection point is located;

[0108] The cross-track spatial resolution of the orbit where the altimeter observation point is located refers to the spatial resolution in the direction perpendicular to the orbit where the altimeter observation point is located and perpendicular to the sea level where the altimeter observation point is located;

[0109] The along-track spatial resolution of the track where the GNSS-R mirror reflection point is located refers to the spatial resolution of a GNSS-R mirror reflection point along the track where the GNSS-R mirror reflection point is located.

[0110] It is understandable that, referring to Figure 4 A distribution diagram of a first equivalent observation area and a second equivalent observation area of ​​an embodiment of the present application is shown. The first equivalent observation area refers to a GNSS-R equivalent observation area established with the GNSS-R mirror reflection point O1 in the same calibration comparison point as the center and with the GNSS-R sea surface height along-track and cross-track spatial resolutions as side lengths. The second equivalent observation area refers to an altimeter equivalent observation area established with the GNSS-R mirror reflection point as the center and with the altimeter cross-track spatial resolution and the GNSS-R along-track spatial resolution as side lengths.

[0111] Reference Figure 5 A distribution diagram of a third equivalent observation area and a fourth equivalent observation area of ​​an embodiment of the present application is shown. The third equivalent observation area refers to a GNSS-R equivalent observation area established with the altimeter observation point in the same calibration comparison point as the center and with the GNSS-R sea surface height along-track and cross-track spatial resolutions as side lengths. The fourth equivalent observation area refers to the altimeter equivalent observation area established with the altimeter observation point as the center and with the altimeter cross-track spatial resolution and the GNSS-R along-track spatial resolution as side lengths.

[0112] Among them, in one area, the geoids at different locations are not the same. Therefore, in order to measure the geoid level of the equivalent observation area, it is necessary to calculate the average geoid of the equivalent observation area. The specific calculation method is not limited in this application.

[0113] By calculating the difference in geoid heights between two equivalent observation areas centered on the GNSS-R mirror reflection point in the same calibration comparison point, namely, the difference in the first geoid height, and the difference in geoid heights between two equivalent observation areas centered on the altimeter observation point, namely, the difference in the second geoid height, only the calibration comparison points whose difference in the first geoid height and the difference in the second geoid height are both less than the preset calibration accuracy are retained. The calibration comparison points with large geoid changes can be deleted to avoid the influence of the geoid error on the accuracy of the calibration result. The influence of the change amplitude of the geoid on the calibration comparison points determined under the preset calibration accuracy is greatly reduced, which helps to improve the accuracy of the calibration result.

[0114] Reference Figure 6 A calibration point distribution diagram that meets the pairing requirements of an embodiment of the present application is shown. In the embodiment of the present application, any of the calibration comparison point determination methods described above and any combination of calibration comparison point determination methods are beneficial to reducing the error in the process of selecting calibration comparison points. On this basis, by adjusting the time matching and space matching thresholds between the GNSS-R sea surface height and the altimeter sea surface height observation value, and / or using other methods described above, effective control of the calibration comparison point error can be achieved, and further accurate on-orbit calibration of different GNSS-R sea surface height calibration accuracies can be achieved. At the same time, the calibration method based on the same satellite receiving platform is conducive to the real-time acquisition of measurement data, and rapid calibration is achieved on the basis of ensuring a small error.

[0115] Further, refer to Figure 7 The graph shown in the embodiment of the present application shows a change in the average deviation of the sea surface height inverted by a GNSS-R system as a function of the number of calibration points. The more calibration pairs there are, the higher the calibration accuracy is. When the number of calibration pairs is greater than 4000, the average value of the GNSS-R sea surface height system deviation tends to be stable and close to the true value of 0 cm.

[0116] Step 103: performing error correction on the measurement data of the calibration comparison point to obtain corrected measurement data of the calibration comparison point, wherein the corrected measurement data includes the corrected measurement height of the GNSS-R mirror reflection point and the corrected measurement height of the altimeter observation point.

[0117] After the calibration comparison point is determined in step 102, since tides, electromagnetic waves, the atmosphere, etc. may affect the height measurement results during the sea level measurement, resulting in certain errors in the height measurement results, it is necessary to perform error correction on the measurement data of the calibration comparison point.

[0118] In an optional embodiment of the present application, the corrected measurement data includes the corrected measurement height of the GNSS-R mirror reflection point and the corrected measurement height of the altimeter observation point. Step 103 of performing error correction on the measurement data of the calibration comparison point to obtain the corrected measurement data of the calibration comparison point may include:

[0119] Step S300, performing error correction on the measurement data of the GNSS-R mirror reflection point in the calibration comparison point to obtain the corrected measurement height of the GNSS-R mirror reflection point;

[0120] Step S301: performing error correction on the measurement data of the altimeter observation point in combination with the measurement data of other altimeter observation points on the track where the altimeter observation point is located, to obtain a corrected measurement height of the altimeter observation point.

[0121] Optionally, step S300 performs error correction on the measurement data of the GNSS-R specular reflection point in the calibration comparison point, which may include at least one of the following:

[0122] Step S400, performing tropospheric delay correction on the measurement data of the GNSS-R mirror reflection point in the calibration comparison point;

[0123] Step S401, performing sea surface electromagnetic deviation correction on the measurement data of the GNSS-R mirror reflection point in the calibration comparison point;

[0124] Step S402, performing ionospheric delay correction on the measurement data of the GNSS-R mirror reflection point in the calibration comparison point;

[0125] Step S403, performing solid tide correction on the measurement data of the GNSS-R mirror reflection point in the calibration comparison point;

[0126] Step S404, performing polar tide correction on the measurement data of the GNSS-R specular reflection point in the calibration comparison point;

[0127] Step S405: performing ocean tide correction on the measurement data of the GNSS-R specular reflection point in the calibration comparison point.

[0128] In view of the influence of the atmosphere on the delay of the sea level detection signal, in order to avoid the sea level detection error caused by signal delay, it is necessary to correct the sea surface electromagnetic deviation to perform tropospheric delay correction and / or ionospheric delay correction on the detection data of the GNSS-R mirror reflection point. Specifically, the tropospheric model and / or ionospheric model can be constructed by collecting meteorological parameters, or error correction can be performed through synchronous observation, which is not limited in the present application.

[0129] Sea surface electromagnetic deviation is usually caused by the irregular distribution of sea surface waves. In the embodiment of the present application, the sea surface electromagnetic deviation can be corrected by utilizing the sea surface empirical relationship constructed with wind speed parameters or by deleting calibration comparison points that are greatly affected by the sea surface electromagnetic deviation, or other methods, which are not limited in the present application.

[0130] Solid tide correction, polar tide correction and ocean tide correction all belong to tidal correction. Therefore, the measurement data of the GNSS-R mirror reflection point can be corrected by constructing a corresponding tidal model and correcting the variables in the model according to the data obtained from the sea surface observation station, or by deleting the calibration comparison points that are greatly affected by at least one of the solid tide, polar tide and ocean tide, or other methods, which are not limited in this application.

[0131] By using at least one of the methods described in step S400 to step S405 , the influence of natural factors on the measurement data of the GNSS-R specular reflection point can be greatly reduced.

[0132] In an optional embodiment of the present application, the step S301 of combining the measurement data of other altimeter observation points on the track where the altimeter observation point is located to perform error correction on the measurement data of the altimeter observation point includes:

[0133] Step S500, performing a first error correction on the measurement data of the altimeter observation point and the measurement data of the other altimeter observation points to obtain a first corrected height of the altimeter observation point and a second corrected height of the other altimeter observation points, wherein the first error correction includes at least one of a tropospheric delay correction, a sea surface electromagnetic deviation correction, an ionospheric delay correction, a solid tide correction, a polar tide correction, and an ocean tide correction;

[0134] Step S501, performing absolute calibration processing on the first calibration height and the second calibration height to obtain a third calibration height of the altimeter observation point and a fourth calibration height of the other altimeter observation points respectively;

[0135] Step S502: Smoothing the third calibrated altitude and the fourth calibrated altitude according to the along-track spatial resolution of the GNSS-R mirror reflection point to obtain the calibrated measurement altitude of the altimeter observation point.

[0136] Among them, other altimeter observation points refer to altimeter observation points that are on the same track and close to the altimeter observation point in the calibration comparison point, such as altimeter observation point A in the calibration comparison point. Other altimeter observation points can be two altimeter observation points located on the front and rear sides of the track where the altimeter observation point is located. The selection of other altimeter observation points can be based on the actual situation during the calibration process.

[0137] Optionally, the average position of the other altimeter observation points may be the same as the position of the altimeter observation point, and the average position refers to the center position of points at multiple different positions. As an example, the other altimeter observation points may be selected as two altimeter observation points on the same track as the altimeter observation point in the calibration comparison point, and the two altimeter observation points are symmetrical about the altimeter observation point in the calibration comparison point.

[0138] Taking into account the influence of tides, atmosphere, and electromagnetic waves, similar to the error correction of GNSS-R measurement data, the measurement data of the altimeter observation point and other altimeter observation points also need to perform at least one of tropospheric delay correction, sea surface electromagnetic deviation correction, ionospheric delay correction, solid tide correction, polar tide correction and ocean tide correction, that is, a first error correction is performed on the measurement data of the altimeter observation point and the measurement data of the other altimeter observation points to obtain a first corrected height of the altimeter observation point and a second corrected height of the other altimeter observation points.

[0139] Absolute calibration refers to correcting the first correction height and the second correction height according to the measurement results of the altimeter observation point by any of the methods such as tide gauge station calibration, offshore platform calibration and GPS buoy calibration, to obtain the third correction height and the fourth correction height to ensure the accuracy of the measured height of the altimeter observation point.

[0140] At the same time, in order to ensure the smoothness of the data, as described in step S502, it is also necessary to determine the smoothing accuracy based on the along-track spatial resolution of the GNSS-R mirror reflection point, and then smooth the third corrected height and the fourth corrected height to obtain the continuous measured heights of the smoothed altimeter observation point and other altimeter observation points, thereby obtaining the corrected measured height of the altimeter observation point.

[0141] Optionally, at the same calibration comparison point, the accuracy of the smoothing processing can be made the same as the along-track spatial resolution of the GNSS-R mirror reflection point corresponding to the altimeter observation point, thereby ensuring the consistency between the correction accuracy of the altimeter observation point and the along-track spatial resolution of the GNSS-R mirror reflection point, and avoiding the impact of inconsistent accuracy on the deviation between the GNSS-R mirror reflection point and the altimeter observation point.

[0142] In an optional embodiment of the present application, after smoothing the first corrected height and the second corrected height according to the along-track spatial resolution of the GNSS-R specular reflection point in step S502, the error correction of the measurement data of the altimeter observation point in step S301 may also include:

[0143] Step S600, performing geoid correction on the calibrated measured height of the altimeter observation point to obtain a final calibrated height of the altimeter observation point;

[0144] Correspondingly, the step 104 of calculating based on the GNSS-R mirror reflection point corrected measurement height and the altimeter observation point corrected measurement height to obtain the measurement deviation data of the calibration comparison point includes:

[0145] Step S601: Calculate based on the final corrected height of the altimeter observation point and the corrected measured height of the GNSS-R mirror reflection point to obtain the measurement deviation data of the calibration comparison point.

[0146] In order to further ensure the accuracy of the measured height of the altimeter observation point, the geoid correction can be performed on the corrected height of the altimeter observation point after step S502. Optionally, the correction amount of the geoid correction can be the difference in geoid height between the GNSS-R mirror reflection point and the altimeter observation point in the calibration comparison point. Specifically, the correction amount can be determined as the difference in the second geoid height calculated in step S205. In this way, some calibration comparison points with relatively large geoid changes are deleted, and the adaptability of the correction amount within a certain range is guaranteed, thereby improving the correction efficiency.

[0147] Step 104 , performing calculation based on the GNSS-R mirror reflection point corrected measurement height and the altimeter observation point corrected measurement height to obtain measurement deviation data of the calibration comparison point.

[0148] The GNSS-R mirror reflection point calibrated measurement height and the altimeter observation point calibrated measurement height in the same calibration comparison point are subtracted to obtain measurement deviation data of at least one calibration comparison point.

[0149] Step 105 : performing linear interpolation on the measurement deviation data according to different angles of the GNSS-R mirror reflection points in the calibration comparison points to obtain a calibration result.

[0150] Taking into account the differences in GNSS-R mirror reflection points in different calibration comparison points, the angles of the GNSS-R mirror reflection points themselves, such as azimuth, elevation, etc., may be different. Therefore, by interpolating the measurement deviation data corresponding to the reflection angles at different angles, the measurement results of the GNSS-R satellite inversion of the sea surface height based on different reflection angles can be obtained. Of course, the observation status of different GNSS-R mirror reflection points is not limited to the angle information of the reflection angle itself. In the embodiment of the present application, the measurement deviation data of the calibration comparison points can also be multi-dimensionally interpolated according to other observation status information of the GNSS-R mirror reflection points, such as the observation platform, the observation satellite, etc., so as to obtain the measurement deviation data of the calibration comparison points corresponding to multiple complex variables, thereby improving the accuracy of the calibration results.

[0151] In an optional embodiment of the present application, the step 105 of performing linear interpolation on the measurement deviation data according to different angles of the GNSS-R mirror reflection point in the calibration comparison point to obtain the calibration result may include:

[0152] Step S700, classifying the measurement deviation data according to different satellite systems to obtain measurement deviation data of different satellite systems;

[0153] Step S701: Perform two-dimensional linear interpolation on the measurement deviation data of the different satellite systems according to the elevation angle and azimuth angle of the GNSS-R mirror reflection point in the calibration comparison point to obtain calibration results of the different satellite systems.

[0154] In GNSS, the elevation angle is used to describe the height of the observed object relative to the observer; the azimuth angle refers to the compass direction, which is the angular offset of the observed object relative to the observer on the horizontal plane.

[0155] The GNSS-R mirror reflection points and altimeter observation points in the calibration comparison points all belong to the same satellite platform, but the measurement data of different calibration comparison points may come from different satellite systems. Considering the differences in the measurement data of different satellite systems, the measurement deviation data of the calibration comparison points can be divided first according to the different satellite systems from which the calibration comparison points data come.

[0156] Furthermore, on the basis of dividing the measurement deviation data of calibration comparison points of different satellite systems, the azimuth and elevation angles of the GNSS-R mirror reflection points in the calibration comparison points are used as variables to perform two-dimensional linear interpolation on the measurement deviation data of the calibration comparison points under the same satellite system, thereby obtaining the calibration results of GNSS-R mirror reflection points with different angle information during GNSS-R sea surface height measurement.

[0157] In an optional embodiment of the present application, after obtaining the calibration result in step 105, the method further includes:

[0158] Step S800, obtaining first sea surface height measurement data, wherein the first sea surface height measurement data is obtained by measuring a sea surface inversion signal from a satellite, and the first sea surface height measurement data includes an elevation angle and an azimuth angle of a measurement point;

[0159] Step S801: Correct the first sea level height measurement data by querying a corresponding correction deviation in the calibration result based on the elevation angle and the azimuth angle of the measurement point.

[0160] Taking into account the high accuracy of the altimeter sea surface height measurement technology and the high efficiency of the GNSS-R inversion sea surface height technology, after obtaining the measurement data of the GNSS-R inversion sea surface height, that is, the first sea surface height measurement data, the corresponding correction deviation can be queried in the calibration result according to the elevation angle and azimuth angle of the observation point in the first sea surface height measurement data. Specifically, the corresponding correction deviation can be queried according to the elevation angle and azimuth angle in the form of a two-dimensional lookup table, so as to correct the first sea surface height measurement data, which not only improves the measurement speed of the sea surface height measurement, but also ensures the accuracy.

[0161] In summary, the embodiment of the present application provides a fast calibration method for GNSS-R sea surface measurement height. After obtaining the height measurement data of the target sea surface, at least one calibration comparison point is determined according to the altimeter measurement data and the GNSS-R measurement data, and the measurement data of the calibration comparison point is error corrected to obtain the GNSS-R mirror reflection point corrected measurement height and the altimeter observation point corrected measurement height of the calibration comparison point, and then based on the GNSS-R mirror reflection point corrected measurement height and the altimeter observation point corrected measurement height, calculation is performed to obtain the measurement deviation data of the calibration comparison point, and finally the measurement deviation data is linearly interpolated according to the different angles of the GNSS-R mirror reflection point in the calibration comparison point to obtain the calibration result. The calibration method based on the same platform realizes the rapid on-orbit calibration of GNSS-R sea surface height. At the same time, by adjusting the time matching and space matching thresholds between GNSS-R sea surface height and altimeter sea surface height observations, the comparison point error during the calibration of GNSS-R satellite inverted sea surface height is effectively reduced, further realizing the precise on-orbit calibration of different GNSS-R sea surface height calibration accuracies.

[0162] Reference Figure 8 , shows a structural block diagram of an embodiment of a GNSS-R sea surface height rapid calibration device of the present application, the device 200 comprises:

[0163] A data acquisition module 201 is used to acquire height measurement data of a target sea surface, wherein the height measurement data includes altimeter measurement data and GNSS-R measurement data, and both the altimeter measurement data and the GNSS-R measurement data are derived from the same satellite receiving platform;

[0164] A calibration comparison point determination module 202 is used to determine at least one calibration comparison point according to the altimeter measurement data and the GNSS-R measurement data, wherein an altimeter observation point and a GNSS-R mirror reflection point together constitute a calibration comparison point, and the calibration comparison point meets the preset time and space requirements;

[0165] An error correction module 203 is used to perform error correction on the measurement data of the calibration comparison point to obtain corrected measurement data of the calibration comparison point, wherein the corrected measurement data includes a corrected measurement height of a GNSS-R mirror reflection point and a corrected measurement height of an altimeter observation point;

[0166] A measurement deviation calculation module 204 is used to calculate based on the GNSS-R mirror reflection point correction measurement height and the altimeter observation point correction measurement height to obtain the measurement deviation data of the calibration comparison point;

[0167] The interpolation module 205 is used to perform linear interpolation on the measurement deviation data according to different angles of the GNSS-R mirror reflection points in the calibration comparison points to obtain a calibration result.

[0168] Optionally, the calibration comparison point determination module may include:

[0169] A quality screening submodule, used for screening the measurement data that meets the preset quality requirements from the altimeter measurement data and the GNSS-R measurement data to obtain candidate altimeter measurement data and candidate GNSS-R measurement data;

[0170] The time and space requirement screening submodule is used to screen the altimeter observation points and GNSS-R mirror reflection points used for calibration comparison in the altimeter measurement data and the GNSS-R measurement data according to the preset time and space requirements, and obtain at least one calibration comparison point.

[0171] Optionally, the time and space requirements include at least one of the following:

[0172] At a calibration comparison point, the difference between the acquisition time of the measurement data of the GNSS-R specular reflection point and the acquisition time of the measurement data of the altimeter observation point is less than a first preset time length;

[0173] At a calibration comparison point, the distance between the GNSS-R mirror reflection point and the altimeter observation point is less than half of the cross-track spatial resolution of the track where the GNSS-R mirror reflection point is located;

[0174] In one calibration point, the GNSS-R mirror reflection point and the altimeter observation point belong to the same ascending orbit or the GNSS-R mirror reflection point and the altimeter observation point belong to the same descending orbit.

[0175] Optionally, the calibration comparison point determination module may further include:

[0176] A first equivalent observation area construction submodule is used for, after selecting the GNSS-R mirror reflection points and the altimeter observation points for calibration comparison in the altimeter measurement data and the GNSS-R measurement data according to preset time and space requirements, for the same calibration comparison point, taking the GNSS-R mirror reflection point in the calibration comparison point as the center point, and based on the along-track spatial resolution of the track where the GNSS-R mirror reflection point in the calibration comparison point is located and the cross-track spatial resolution of the track where the GNSS-R mirror reflection point is located, to construct a first equivalent observation area of ​​the calibration comparison point;

[0177] A second equivalent observation area construction submodule is used for, after selecting the GNSS-R mirror reflection points and the altimeter observation points for calibration comparison in the altimeter measurement data and the GNSS-R measurement data according to preset time and space requirements, for the same calibration comparison point, taking the GNSS-R mirror reflection point in the calibration comparison point as the center point, and based on the along-track spatial resolution of the track where the GNSS-R mirror reflection point in the calibration comparison point is located and the cross-track spatial resolution of the track where the altimeter observation point is located, to construct a second equivalent observation area of ​​the calibration comparison point;

[0178] A third equivalent observation area construction submodule is used for, after selecting the GNSS-R mirror reflection points and the altimeter observation points for calibration comparison in the altimeter measurement data and the GNSS-R measurement data according to preset time and space requirements, for the same calibration comparison point, taking the altimeter observation point in the calibration comparison point as the center point, based on the along-track spatial resolution of the track where the GNSS-R mirror reflection point in the calibration comparison point is located and the cross-track spatial resolution of the track where the GNSS-R mirror reflection point is located, to construct a third equivalent observation area of ​​the calibration comparison point;

[0179] a fourth equivalent observation area construction submodule, for, after screening the GNSS-R mirror reflection points and the altimeter observation points for calibration comparison in the altimeter measurement data and the GNSS-R measurement data according to preset time and space requirements, taking the altimeter observation point in the calibration comparison point as the center point, and constructing a fourth equivalent observation area of ​​the calibration comparison point based on the along-track spatial resolution of the track where the GNSS-R mirror reflection point in the calibration comparison point is located and the cross-track spatial resolution of the track where the altimeter observation point is located;

[0180] A first geoid height difference calculation submodule, used to calculate the average geoid heights in the first equivalent observation area and the second equivalent observation area respectively, and calculate the difference to obtain the difference in the first geoid heights between the first equivalent observation area and the second equivalent observation area;

[0181] A second geoid height difference calculation submodule is used to calculate the average geoid heights in the third equivalent observation area and the fourth equivalent observation area respectively, and calculate the difference to obtain the difference in the second geoid heights between the third equivalent observation area and the fourth equivalent observation area;

[0182] The screening submodule is used to retain the calibration comparison point if the difference between the first geoid height and the difference between the second geoid height are both less than a preset accuracy.

[0183] Optionally, the corrected measurement data includes a GNSS-R mirror reflection point corrected measurement height and an altimeter observation point corrected measurement height;

[0184] The error correction module may include:

[0185] A GNSS-R measurement data correction submodule, used to perform error correction on the measurement data of the GNSS-R mirror reflection point in the calibration comparison point to obtain the corrected measurement height of the GNSS-R mirror reflection point;

[0186] The altimeter measurement data correction submodule is used to perform error correction on the measurement data of the altimeter observation point in combination with the measurement data of other altimeter observation points on the track where the altimeter observation point is located, so as to obtain the corrected measurement height of the altimeter observation point.

[0187] Optionally, the GNSS-R measurement data correction submodule may include at least one of the following modules:

[0188] A tropospheric delay correction submodule, used for performing tropospheric delay correction on the measurement data of the GNSS-R mirror reflection point in the calibration comparison point;

[0189] A sea surface electromagnetic deviation correction submodule, used to correct the sea surface electromagnetic deviation of the measurement data of the GNSS-R mirror reflection point in the calibration comparison point;

[0190] An ionospheric delay correction submodule, used to perform ionospheric delay correction on the measurement data of the GNSS-R mirror reflection point in the calibration comparison point;

[0191] A solid tide correction submodule, used for performing solid tide correction on the measurement data of the GNSS-R mirror reflection point in the calibration comparison point;

[0192] A polar tide correction submodule, used for performing polar tide correction on the measurement data of the GNSS-R mirror reflection point in the calibration comparison point;

[0193] The ocean tide correction submodule is used to perform ocean tide correction on the measurement data of the GNSS-R mirror reflection point in the calibration comparison point.

[0194] Optionally, the altimeter measurement data correction submodule may include:

[0195] a first error correction submodule, configured to perform a first error correction on the measurement data of the altimeter observation point and the measurement data of the other altimeter observation points to obtain a first corrected height of the altimeter observation point and a second corrected height of the other altimeter observation points, wherein the first error correction includes at least one of a tropospheric delay correction, a sea surface electromagnetic deviation correction, an ionospheric delay correction, a solid tide correction, a polar tide correction, and an ocean tide correction;

[0196] an absolute calibration submodule, configured to perform absolute calibration processing on the first calibration height and the second calibration height to obtain a third calibration height of the altimeter observation point and a fourth calibration height of the other altimeter observation points, respectively;

[0197] The smoothing submodule is used to smooth the third corrected height and the fourth corrected height according to the along-track spatial resolution of the GNSS-R mirror reflection point to obtain the corrected measurement height of the altimeter observation point.

[0198] Optionally, the accuracy of the smoothing process is the same as the along-track spatial resolution of the GNSS-R mirror reflection point corresponding to the altimeter observation point, and the average position of the other altimeter observation points is the same as the position of the altimeter observation point.

[0199] Optionally, the altimeter measurement data correction submodule may further include:

[0200] a geoid correction submodule, configured to perform geoid correction on the corrected measured height of the altimeter observation point after smoothing the first corrected height and the second corrected height according to the along-track spatial resolution of the GNSS-R mirror reflection point, so as to obtain a final corrected height of the altimeter observation point;

[0201] Correspondingly, the interpolation module may include:

[0202] The first interpolation submodule is used to calculate based on the final corrected height of the altimeter observation point and the corrected measured height of the GNSS-R mirror reflection point to obtain the measurement deviation data of the calibration comparison point.

[0203] Optionally, the correction amount of the geoid correction is the difference in geoid height between the GNSS-R mirror reflection point and the altimeter observation point in the calibration comparison point.

[0204] Optionally, the interpolation module may include:

[0205] A classification submodule, used to classify the measurement deviation data according to different satellite systems to obtain the measurement deviation data of different satellite systems;

[0206] The two-dimensional linear interpolation submodule is used to perform two-dimensional linear interpolation on the measurement deviation data of the different satellite systems according to the elevation angle and azimuth angle of the GNSS-R mirror reflection point in the calibration comparison point to obtain calibration results of the different satellite systems.

[0207] Optionally, the device may further include:

[0208] A first sea surface height measurement data acquisition module, configured to acquire first sea surface height measurement data after obtaining the calibration result, wherein the first sea surface height measurement data is obtained by measuring the sea surface inversion signal of the satellite, and the first sea surface height measurement data includes the elevation angle and azimuth angle of the measurement point;

[0209] A correction module is used to correct the first sea level height measurement data by querying a corresponding correction deviation in the calibration result based on the elevation angle and the azimuth angle of the measurement point.

[0210] Fig. 9 1 is a block diagram of an electronic device 600 for rapid calibration of GNSS-R sea surface height measurement according to an embodiment of the present application. For example, the electronic device 600 may be a mobile phone, a computer, a digital broadcast terminal, a messaging device, a game console, a tablet device, a medical device, a fitness device, a personal digital assistant, etc.

[0211] Reference Fig. 9 , the electronic device 600 may include one or more of the following components: a processing component 602 , a memory 604 , a power component 606 , a multimedia component 608 , an audio component 610 , an input / output (I / O) interface 612 , a sensor component 614 , and a communication component 616 .

[0212] The processing component 602 generally controls the overall operation of the electronic device 600, such as operations associated with display, phone calls, data communications, camera operations, and recording operations. The processing component 602 may include one or more processors 620 to execute instructions to complete all or part of the steps of the above-mentioned GNSS-R sea surface measurement height rapid calibration method. In addition, the processing component 602 may include one or more modules to facilitate the interaction between the processing component 602 and other components. For example, the processing component 602 may include a multimedia module to facilitate the interaction between the multimedia component 608 and the processing component 602.

[0213] The memory 604 is configured to store various types of data to support operations on the electronic device 600. Examples of such data include instructions for any application or method operating on the electronic device 600, contact data, phone book data, messages, pictures, videos, etc. The memory 604 can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic disk or optical disk.

[0214] The power supply component 606 provides power to the various components of the electronic device 600. The power supply component 606 may include a power management system, one or more power supplies, and other components associated with generating, managing, and distributing power to the electronic device 600.

[0215] The multimedia component 608 includes a screen that provides an output interface between the electronic device 600 and the user. In some embodiments, the screen may include a liquid crystal display (LCD) and a touch panel (TP). If the screen includes a touch panel, the screen may be implemented as a touch screen to receive input signals from the user. The touch panel includes one or more touch sensors to sense touch, slide, and gestures on the touch panel. The touch sensor may not only sense the boundaries of the touch or slide action, but also detect the duration and pressure associated with the touch or slide operation. In some embodiments, the multimedia component 608 includes a front camera and / or a rear camera. When the electronic device 600 is in an operating mode, such as a shooting mode or a video mode, the front camera and / or the rear camera may receive external multimedia data. Each front camera and the rear camera may be a fixed optical lens system or have a focal length and optical zoom capability.

[0216] The audio component 610 is configured to output and / or input audio signals. For example, the audio component 610 includes a microphone (MIC), and when the electronic device 600 is in an operating mode, such as a call mode, a recording mode, and a voice information processing mode, the microphone is configured to receive an external audio signal. The received audio signal can be further stored in the memory 604 or sent via the communication component 616. In some embodiments, the audio component 610 also includes a speaker for outputting audio signals.

[0217] I / O interface 612 provides an interface between processing component 602 and peripheral interface modules, such as keyboards, click wheels, buttons, etc. These buttons may include but are not limited to: a home button, a volume button, a start button, and a lock button.

[0218] The sensor assembly 614 includes one or more sensors for providing various aspects of status assessment for the electronic device 600. For example, the sensor assembly 614 can detect the open / closed state of the electronic device 600, the relative positioning of components, such as the display and keypad of the electronic device 600, and the sensor assembly 614 can also detect the position change of the electronic device 600 or a component of the electronic device 600, the presence or absence of user contact with the electronic device 600, the orientation or acceleration / deceleration of the electronic device 600, and the temperature change of the electronic device 600. The sensor assembly 814 may include a proximity sensor configured to detect the presence of nearby objects without any physical contact. The sensor assembly 614 may also include an optical sensor, such as a CMOS or CCD image sensor, for use in imaging applications. In some embodiments, the sensor assembly 614 may also include an acceleration sensor, a gyroscope sensor, a magnetic sensor, a pressure sensor, or a temperature sensor.

[0219] The communication component 616 is configured to facilitate wired or wireless communication between the electronic device 600 and other devices. The electronic device 600 can access a wireless network based on a communication standard, such as WiFi, 2G or 3G, or a combination thereof. In an exemplary embodiment, the communication component 616 receives a broadcast signal or broadcast-related information from an external broadcast management system via a broadcast channel. In an exemplary embodiment, the communication component 616 also includes a near field communication (NFC) module to facilitate short-range communication. For example, the NFC module can be implemented based on radio frequency information processing (RFID) technology, infrared data association (IrDA) technology, ultra-wideband (UWB) technology, Bluetooth (BT) technology and other technologies.

[0220] In an exemplary embodiment, the electronic device 600 may be implemented by one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), controllers, microcontrollers, microprocessors or other electronic components to perform the above-mentioned GNSS-R sea surface measurement height rapid calibration method.

[0221] In an exemplary embodiment, a non-transitory computer-readable storage medium including instructions is also provided, such as a memory 604 including instructions, and the instructions can be executed by a processor 620 of an electronic device 600 to perform the above method. For example, the non-transitory computer-readable storage medium can be a ROM, a random access memory (RAM), a CD-ROM, a magnetic tape, a floppy disk, an optical data storage device, etc.

[0222] A non-transitory computer-readable storage medium, when the instructions in the storage medium are executed by a processor of an electronic device (server or terminal), enables the processor to execute Figure 1 or Figure 2 The fast calibration method for GNSS-R sea surface measurement height is shown.

[0223] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0224] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0225] The above is a detailed introduction to a GNSS-R sea surface measurement height rapid calibration method, device, electronic device and storage medium provided by the present application. This article uses specific examples to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea; at the same time, for general technical personnel in this field, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A rapid calibration method for GNSS-R sea surface measurement height, characterized in that: The method comprises: Acquire height measurement data of the target sea surface, wherein the height measurement data includes altimeter measurement data and GNSS-R measurement data, and the altimeter measurement data and GNSS-R measurement data are both derived from the same satellite receiving platform; Determine at least one calibration comparison point according to the altimeter measurement data and the GNSS-R measurement data, wherein an altimeter observation point and a GNSS-R mirror reflection point together constitute a calibration comparison point, and the calibration comparison point meets the preset time and space requirements; Performing error correction on the measurement data of the calibration comparison point to obtain corrected measurement data of the calibration comparison point, wherein the corrected measurement data includes a corrected measurement height of a GNSS-R mirror reflection point and a corrected measurement height of an altimeter observation point; Calculating based on the GNSS-R mirror reflection point corrected measurement height and the altimeter observation point corrected measurement height, obtaining the measurement deviation data of the calibration comparison point; Performing linear interpolation on the measurement deviation data according to different angles of the GNSS-R mirror reflection point in the calibration comparison point to obtain a calibration result; The linear interpolation of the measurement deviation data according to different angles of the GNSS-R mirror reflection point in the calibration comparison point to obtain the calibration result includes: Classifying the measurement deviation data according to different satellite systems to obtain measurement deviation data of different satellite systems; Two-dimensional linear interpolation is performed on the measurement deviation data of the different satellite systems according to the elevation angle and azimuth angle of the GNSS-R mirror reflection point in the calibration comparison point to obtain calibration results of the different satellite systems.

2. The method according to claim 1, characterized in that The determining at least one calibration comparison point according to the altimeter measurement data and the GNSS-R measurement data comprises: Screening measurement data that meets preset quality requirements from the altimeter measurement data and the GNSS-R measurement data to obtain candidate altimeter measurement data and candidate GNSS-R measurement data; According to preset time and space requirements, altimeter observation points and GNSS-R mirror reflection points for calibration comparison are selected from the altimeter measurement data and the GNSS-R measurement data to obtain at least one calibration comparison point.

3. The method according to claim 2, characterized in that The time and space requirements include at least one of the following: At a calibration comparison point, the difference between the acquisition time of the measurement data of the GNSS-R specular reflection point and the acquisition time of the measurement data of the altimeter observation point is less than a first preset time length; At a calibration comparison point, the distance between the GNSS-R mirror reflection point and the altimeter observation point is less than half of the cross-track spatial resolution of the track where the GNSS-R mirror reflection point is located; In one calibration point, the GNSS-R mirror reflection point and the altimeter observation point belong to the same ascending orbit or the GNSS-R mirror reflection point and the altimeter observation point belong to the same descending orbit.

4. The method according to claim 2, characterized in that: After selecting the GNSS-R mirror reflection points and the altimeter observation points for calibration comparison in the altimeter measurement data and the GNSS-R measurement data according to the preset time and space requirements, for the same calibration comparison point, determining at least one calibration comparison point according to the altimeter measurement data and the GNSS-R measurement data further includes: Taking the GNSS-R mirror reflection point in the calibration comparison point as the center point, based on the along-track spatial resolution of the track where the GNSS-R mirror reflection point in the calibration comparison point is located and the cross-track spatial resolution of the track where the GNSS-R mirror reflection point is located, construct a first equivalent observation area of ​​the calibration comparison point; Taking the GNSS-R mirror reflection point in the calibration comparison point as the center point, based on the along-track spatial resolution of the track where the GNSS-R mirror reflection point in the calibration comparison point is located and the cross-track spatial resolution of the track where the altimeter observation point is located, construct a second equivalent observation area of ​​the calibration comparison point; Taking the altimeter observation point in the calibration comparison point as the center point, based on the along-track spatial resolution of the track where the GNSS-R mirror reflection point in the calibration comparison point is located and the cross-track spatial resolution of the track where the GNSS-R mirror reflection point is located, construct a third equivalent observation area of ​​the calibration comparison point; Taking the altimeter observation point in the calibration comparison point as the center point, based on the along-track spatial resolution of the track where the GNSS-R mirror reflection point in the calibration comparison point is located and the cross-track spatial resolution of the track where the altimeter observation point is located, construct a fourth equivalent observation area of ​​the calibration comparison point; Calculating the average geoid heights in the first equivalent observation area and the second equivalent observation area respectively, and calculating the difference, to obtain the difference between the first geoid heights of the first equivalent observation area and the second equivalent observation area; Calculating the average geoid heights in the third equivalent observation area and the fourth equivalent observation area respectively, and calculating the difference, to obtain the difference in the second geoid height between the third equivalent observation area and the fourth equivalent observation area; If the difference between the first geoid height and the difference between the second geoid height are both less than a preset accuracy, the calibration comparison point is retained.

5. The method according to claim 1, characterized in that The corrected measurement data includes the corrected measurement height of the GNSS-R mirror reflection point and the corrected measurement height of the altimeter observation point, and the error correction of the measurement data of the calibration comparison point to obtain the corrected measurement data of the calibration comparison point includes: Performing error correction on the measurement data of the GNSS-R mirror reflection point in the calibration comparison point to obtain the corrected measurement height of the GNSS-R mirror reflection point; The measurement data of the altimeter observation point is combined with the measurement data of other altimeter observation points on the orbit where the altimeter observation point is located, and error correction is performed on the measurement data of the altimeter observation point to obtain the corrected measurement height of the altimeter observation point.

6. The method according to claim 5, characterized in that The error correction of the measurement data of the GNSS-R mirror reflection point in the calibration comparison point includes at least one of the following: Performing tropospheric delay correction on the measurement data of the GNSS-R mirror reflection point in the calibration comparison point; Performing sea surface electromagnetic deviation correction on the measurement data of the GNSS-R mirror reflection point in the calibration comparison point; Performing ionospheric delay correction on the measurement data of the GNSS-R mirror reflection point in the calibration comparison point; Performing solid tide correction on the measurement data of the GNSS-R mirror reflection point in the calibration comparison point; Performing polar tide correction on the measurement data of the GNSS-R mirror reflection point in the calibration comparison point; The measurement data of the GNSS-R mirror reflection point in the calibration comparison point is corrected for ocean tides.

7. The method according to claim 5, characterized in that The step of combining the measurement data of other altimeter observation points on the track where the altimeter observation point is located to perform error correction on the measurement data of the altimeter observation point comprises: Performing a first error correction on the measurement data of the altimeter observation point and the measurement data of the other altimeter observation points to obtain a first corrected height of the altimeter observation point and a second corrected height of the other altimeter observation points, wherein the first error correction includes at least one of a tropospheric delay correction, a sea surface electromagnetic deviation correction, an ionospheric delay correction, a solid tide correction, a polar tide correction, and an ocean tide correction; Performing absolute calibration processing on the first calibrated height and the second calibrated height to obtain a third calibrated height of the altimeter observation point and a fourth calibrated height of the other altimeter observation points, respectively; The third corrected height and the fourth corrected height are smoothed according to the along-track spatial resolution of the GNSS-R mirror reflection point to obtain the corrected measurement height of the altimeter observation point.

8. The method according to claim 7, characterized in that The accuracy of the smoothing process is the same as the along-track spatial resolution of the GNSS-R mirror reflection point corresponding to the altimeter observation point, and the average position of the other altimeter observation points is the same as the position of the altimeter observation point.

9. The method according to claim 7, characterized in that: After the third corrected height and the fourth corrected height are smoothed according to the along-track spatial resolution of the GNSS-R specular reflection point, the error correction of the measurement data of the altimeter observation point further includes: Performing geoid correction on the corrected measured height of the altimeter observation point to obtain a final corrected height of the altimeter observation point; The calculating based on the GNSS-R mirror reflection point corrected measurement height and the altimeter observation point corrected measurement height to obtain the measurement deviation data of the calibration comparison point includes: The measurement deviation data of the calibration comparison point is obtained by performing calculation based on the final corrected height of the altimeter observation point and the corrected measured height of the GNSS-R mirror reflection point.

10. The method according to claim 9, characterized in that The correction amount of the geoid correction is the difference in geoid height between the GNSS-R mirror reflection point and the altimeter observation point in the calibration comparison point.

11. The method according to claim 1, characterized in that: After obtaining the calibration result, the method further includes: Acquire first sea surface height measurement data, where the first sea surface height measurement data is measured based on a sea surface inversion signal from a satellite, and the first sea surface height measurement data includes an elevation angle and an azimuth angle of a measurement point; The first sea level height measurement data is corrected by querying a corresponding correction deviation in the calibration result based on the elevation angle and the azimuth angle of the measurement point.

12. A GNSS-R sea surface measurement height rapid calibration device, characterized in that: The device comprises: A data acquisition module is used to acquire height measurement data of a target sea surface, wherein the height measurement data includes altimeter measurement data and GNSS-R measurement data, and both the altimeter measurement data and the GNSS-R measurement data are derived from the same satellite receiving platform; A calibration comparison point determination module, used to determine at least one calibration comparison point according to the altimeter measurement data and the GNSS-R measurement data, wherein an altimeter observation point and a GNSS-R mirror reflection point together constitute a calibration comparison point, and the calibration comparison point meets the preset time and space requirements; An error correction module is used to perform error correction on the measurement data of the calibration comparison point to obtain corrected measurement data of the calibration comparison point, wherein the corrected measurement data includes a corrected measurement height of a GNSS-R mirror reflection point and a corrected measurement height of an altimeter observation point; A measurement deviation calculation module, used to calculate based on the GNSS-R mirror reflection point correction measurement height and the altimeter observation point correction measurement height to obtain the measurement deviation data of the calibration comparison point; An interpolation module, used for performing linear interpolation on the measurement deviation data according to different angles of the GNSS-R mirror reflection point in the calibration comparison point to obtain a calibration result; The interpolation module comprises: A classification submodule, used to classify the measurement deviation data according to different satellite systems to obtain the measurement deviation data of different satellite systems; The two-dimensional linear interpolation submodule is used to perform two-dimensional linear interpolation on the measurement deviation data of the different satellite systems according to the elevation angle and azimuth angle of the GNSS-R mirror reflection point in the calibration comparison point to obtain calibration results of the different satellite systems.

13. The device according to claim 12, characterized in that The calibration comparison point determination module comprises: A quality screening submodule, used for screening the measurement data that meets the preset quality requirements from the altimeter measurement data and the GNSS-R measurement data to obtain candidate altimeter measurement data and candidate GNSS-R measurement data; The time and space requirement screening submodule is used to screen the altimeter observation points and GNSS-R mirror reflection points used for calibration comparison in the altimeter measurement data and the GNSS-R measurement data according to the preset time and space requirements, and obtain at least one calibration comparison point.

14. The device according to claim 13, characterized in that The calibration comparison point determination module further includes: A first equivalent observation area construction submodule is used for, after selecting the GNSS-R mirror reflection points and the altimeter observation points for calibration comparison in the altimeter measurement data and the GNSS-R measurement data according to preset time and space requirements, for the same calibration comparison point, taking the GNSS-R mirror reflection point in the calibration comparison point as the center point, and based on the along-track spatial resolution of the track where the GNSS-R mirror reflection point in the calibration comparison point is located and the cross-track spatial resolution of the track where the GNSS-R mirror reflection point is located, to construct a first equivalent observation area of ​​the calibration comparison point; A second equivalent observation area construction submodule is used for, after selecting the GNSS-R mirror reflection points and the altimeter observation points for calibration comparison in the altimeter measurement data and the GNSS-R measurement data according to preset time and space requirements, for the same calibration comparison point, taking the GNSS-R mirror reflection point in the calibration comparison point as the center point, and based on the along-track spatial resolution of the track where the GNSS-R mirror reflection point in the calibration comparison point is located and the cross-track spatial resolution of the track where the altimeter observation point is located, to construct a second equivalent observation area of ​​the calibration comparison point; A third equivalent observation area construction submodule is used for, after selecting the GNSS-R mirror reflection points and the altimeter observation points for calibration comparison in the altimeter measurement data and the GNSS-R measurement data according to preset time and space requirements, for the same calibration comparison point, taking the altimeter observation point in the calibration comparison point as the center point, based on the along-track spatial resolution of the track where the GNSS-R mirror reflection point in the calibration comparison point is located and the cross-track spatial resolution of the track where the GNSS-R mirror reflection point is located, to construct a third equivalent observation area of ​​the calibration comparison point; a fourth equivalent observation area construction submodule, for, after screening the GNSS-R mirror reflection points and the altimeter observation points for calibration comparison in the altimeter measurement data and the GNSS-R measurement data according to preset time and space requirements, taking the altimeter observation point in the calibration comparison point as the center point, and constructing a fourth equivalent observation area of ​​the calibration comparison point based on the along-track spatial resolution of the track where the GNSS-R mirror reflection point in the calibration comparison point is located and the cross-track spatial resolution of the track where the altimeter observation point is located; A first geoid height difference calculation submodule, used to calculate the average geoid heights in the first equivalent observation area and the second equivalent observation area respectively, and calculate the difference to obtain the difference in the first geoid heights between the first equivalent observation area and the second equivalent observation area; A second geoid height difference calculation submodule is used to calculate the average geoid heights in the third equivalent observation area and the fourth equivalent observation area respectively, and calculate the difference to obtain the difference in the second geoid heights between the third equivalent observation area and the fourth equivalent observation area; The screening submodule is used to retain the calibration comparison point if the difference between the first geoid height and the difference between the second geoid height are both less than a preset accuracy.

15. The device according to claim 12, characterized in that The corrected measurement data includes the corrected measurement height of the GNSS-R mirror reflection point and the corrected measurement height of the altimeter observation point; The error correction module comprises: A GNSS-R measurement data correction submodule, used to perform error correction on the measurement data of the GNSS-R mirror reflection point in the calibration comparison point to obtain the corrected measurement height of the GNSS-R mirror reflection point; The altimeter measurement data correction submodule is used to perform error correction on the measurement data of the altimeter observation point in combination with the measurement data of other altimeter observation points on the track where the altimeter observation point is located, so as to obtain the corrected measurement height of the altimeter observation point.

16. The device according to claim 15, characterized in that The GNSS-R measurement data correction submodule includes at least one of the following modules: A tropospheric delay correction submodule, used for performing tropospheric delay correction on the measurement data of the GNSS-R mirror reflection point in the calibration comparison point; A sea surface electromagnetic deviation correction submodule, used to correct the sea surface electromagnetic deviation of the measurement data of the GNSS-R mirror reflection point in the calibration comparison point; An ionospheric delay correction submodule, used to perform ionospheric delay correction on the measurement data of the GNSS-R mirror reflection point in the calibration comparison point; A solid tide correction submodule, used for performing solid tide correction on the measurement data of the GNSS-R mirror reflection point in the calibration comparison point; A polar tide correction submodule, used for performing polar tide correction on the measurement data of the GNSS-R mirror reflection point in the calibration comparison point; The ocean tide correction submodule is used to perform ocean tide correction on the measurement data of the GNSS-R mirror reflection point in the calibration comparison point.

17. The device according to claim 15, characterized in that The altimeter measurement data correction submodule comprises: a first error correction submodule, configured to perform a first error correction on the measurement data of the altimeter observation point and the measurement data of the other altimeter observation points to obtain a first corrected height of the altimeter observation point and a second corrected height of the other altimeter observation points, wherein the first error correction includes at least one of a tropospheric delay correction, a sea surface electromagnetic deviation correction, an ionospheric delay correction, a solid tide correction, a polar tide correction, and an ocean tide correction; an absolute calibration submodule, configured to perform absolute calibration processing on the first calibration height and the second calibration height to obtain a third calibration height of the altimeter observation point and a fourth calibration height of the other altimeter observation points, respectively; The smoothing submodule is used to smooth the third corrected height and the fourth corrected height according to the along-track spatial resolution of the GNSS-R mirror reflection point to obtain the corrected measurement height of the altimeter observation point.

18. The device according to claim 17, characterized in that The altimeter measurement data correction submodule further includes: a geoid correction submodule, configured to perform geoid correction on the corrected measured height of the altimeter observation point after smoothing the first corrected height and the second corrected height according to the along-track spatial resolution of the GNSS-R mirror reflection point, so as to obtain a final corrected height of the altimeter observation point; The interpolation module comprises: The first interpolation submodule is used to calculate based on the final corrected height of the altimeter observation point and the corrected measured height of the GNSS-R mirror reflection point to obtain the measurement deviation data of the calibration comparison point.

19. The device according to claim 12, characterized in that The device also includes: A first sea surface height measurement data acquisition module, configured to acquire first sea surface height measurement data after obtaining the calibration result, wherein the first sea surface height measurement data is obtained by measuring the sea surface inversion signal of the satellite, and the first sea surface height measurement data includes the elevation angle and azimuth angle of the measurement point; A correction module is used to correct the first sea level height measurement data by querying a corresponding correction deviation in the calibration result based on the elevation angle and the azimuth angle of the measurement point.

20. An electronic device, characterized in that: include: A processor and a memory, wherein the processor executes a computer program stored in the memory to implement the GNSS-R sea surface measurement height rapid calibration method according to any one of claims 1 to 11.

21. A readable storage medium, characterized in that: When the instructions in the storage medium are executed by a processor of a device, the device is enabled to execute the rapid calibration method for GNSS-R sea surface measurement height as described in any one of method claims 1 to 11.

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