34 results about "Geopotential model" patented technology

The invention discloses a GNSS-CCD-integrated zenith telescope high-precision vertical deflection fast measurement method. At a measurement station, the optical axis of a zenith telescope faces to the zenith and takes a picture of a zenith zone so that a CCD fixed star image is obtained, fixed star image coordinates are calculated, exposure epoch is controlled by geodetic coordinates and a GNSS time signal measured by GNSS, fixed star information in the zenith zone is acquired in an appropriate star catalogue according to the measurement station vertical deflection calculated by an EGM2008 geopotential model, coupling identification of fixed stars in a zenith tangent plane zone of a celestial sphere in the star catalogue and in the CCD fixed star image is realized, zenith astronomical coordinates are calculated by least spuare iterative computation, and vertical deflection of the observed point is calculated according to geodetic coordinates. Compared with the prior art, the method provided by the invention has the characteristics of simple operation, time and labor saving and high measurement precision and is suitable for high-precision vertical deflection fast measurement.

The invention discloses a method for improving ocean gravity field interpolation precision based on a submarine topography three-dimensional optimization principle. The method comprises steps of submarine topography data and a global gravity field model being acquired; constructing a three-dimensional ocean gravity anomaly model according to the acquired submarine topographic data and the global gravity field model; performing interpolation calculation on the three-dimensional ocean gravity anomaly model to obtain a geoid three-dimensional correction model; and according to the geoid three-dimensional correction model, determining a gravity anomaly value at an unknown point in the prediction area to obtain a high-precision and high-spatial-resolution marine gravity anomaly map. According to the method, the submarine topography is introduced into a common two-dimensional Kriging formula, a novel submarine topography three-dimensional optimization method is constructed, the precision loss is minimized while the spatial resolution of the global marine gravity anomaly map is improved, the interpolation precision is high, the calculation speed is high, and an effective basis is providedfor improving the submarine gravity matching navigation precision.

The invention provides a sea area gravity anomaly inversion method and a system based on satellite height measurement data, and the method comprises the steps: calculating the sea surface height gradient of a sub-satellite point according to the sea surface height data collected by a satellite altimeter at the sub-satellite point in a preset sea area, and calculating the model vertical line deviation gradient of the sub-satellite point according to the position of the sub-satellite point, subtracting the sea surface height gradient of the sub-satellite point from the model vertical line deviation gradient to obtain the residual gradient of the sub-satellite point; converting the residual gradient of the sub-satellite point into a vertical line deviation grid based on a weighted least square method, and obtaining the residual vertical line deviation of the grid; and calculating the residual gravity anomaly of the grid according to the residual vertical line deviation of the grid, calculating the model gravity anomaly of the grid based on the gravity field model, and adding the model gravity anomaly of the grid and the residual gravity anomaly to obtain the sea area gravity anomaly value of the grid. According to the method, the accurate sea area gravity abnormal value is obtained after strict theoretical derivation.

The invention relates to a radial basis function grid method for constructing a sea area plumb line deviation model based on frequency domain characteristics, which is technically characterized by comprising the following steps of: removing plumb line deviation in a sea plumb line deviation observation value by utilizing medium-long wave frequency spectrum information provided by a global gravityfield model to obtain residual plumb line deviation at an observation point; based on the residual vertical line deviation at the observation point, applying a radial basis function interpolation algorithm to obtain the residual vertical line deviation at the point to be estimated; recovering the model values of the meridian component and the mortise unitary component residual error of the vertical line deviation of the to-be-estimated point to obtain the calculation values of the meridian component and the mortise unitary component residual error of the vertical line deviation of the to-be-estimated point at the to-be-estimated point. The method is reasonable in design, the ocean plumb line deviation observed value serves as basic data, the global gravity field spherical harmonic model iscombined, a radial basis function interpolation method based on frequency domain characteristics is adopted, and the high-precision and high-resolution sea area plumb line deviation model can be constructed.

The invention discloses an earth gravity field model modeling method based on an orbit mask differential operator, which relates to the technical field of satellite gravity detection. The method comprises the steps of: carrying out the data preprocessing of orbit state information, a satellite-borne accelerometer and satellite attitude data, calculating the movement speed of the satellite by usingan orbit mask differential operator so as to obtain the kinetic energy and the rotation position of the satellite, establishing an observation equation meeting the law of conservation of energy through satellite kinetic energy, a rotation position, a conservative force position and a non-conservative force position, estimating a position coefficient correction value under the least square criterion, and determining a final earth gravity field model by adding a reference gravity field model position coefficient. Compared with a traditional method for determining the earth gravity field model by utilizing the orbit Newton polynomial differential speed, the method provided by the invention effectively suppresses high-frequency error amplification to realize noise reduction, is high in flexibility and calculation efficiency, obtains a high-precision satellite speed observation value, and further improves the precision level of the earth gravity field model.

The invention discloses a satellite gravitational gradient data precision verification method based on a tensor invariant theory. The method comprises the following steps: verifying the overall precision of a satellite gravitational gradient tensor and verifying the component independent precision of the satellite gravitational gradient tensor, wherein the component independent precision verification of the satellite gravitational gradient tensor comprises independent precision verification of each component of the satellite gravitational gradient tensor before and after calibration. Accordingto the satellite gravitational gradient data precision verification method based on a tensor invariant theory provided by the invention, on the basis of the tensor invariant theory, the tensor invariant characteristic of a satellite gravitational gradient observation value is applied to precision verification before and after calibration of a gravitational gradient measurement satellite gravimeter, and overall precision verification of the six components of the gravitational gradient tensor is achieved. By introducing a priori gravitational field model for calibration, precision independent verification of the six components of the main diagonal line and an off-diagonal line of the gravitational gradient tensor can be realized.

The invention discloses an inertial navigation precision compensation method based on an airspace Kriging grid method, and the method comprises the steps: removing a low-frequency information model value, calculated based on a global gravity field model, of a disturbance gravity component of an observation point from an observation value of the disturbance gravity component, and obtaining a residual value of the disturbance gravity component of the observation point; on the basis of the residual value of the disturbance gravity component of the observation point, calculating the residual value of the disturbance gravity component of the to-be-estimated point by applying an airspace Kriging grid algorithm; and combining the residual value of the disturbance gravity component of the to-be-estimated point with the low-frequency information model value of the disturbance gravity component of the to-be-estimated point calculated based on the global gravity field model to obtain a disturbance gravity component calculated value of the to-be-estimated point. According to the method, the low-frequency information of the disturbance gravity component is strictly correct in principle, the spectral characteristics of the disturbance gravity component are considered to suppress the grid error influence in a medium-long wave band, and the spatial Kriging technology is utilized to improve the model resolution.

The invention discloses an inertial instrument error correction method based on an airspace bilinear grid function, and the method comprises the steps: removing a low-frequency information model value, calculated based on a global gravity field model, of a disturbance gravity component of an observation point from an observation value of the disturbance gravity component, and obtaining a residual value of the disturbance gravity component of the observation point; on the basis of the residual value of the disturbance gravity component of the observation point, calculating the residual value of the disturbance gravity component of the to-be-estimated point by applying an airspace bilinear grid algorithm; and combining the residual value of the disturbance gravity component of the to-be-estimated point with the low-frequency information model value of the disturbance gravity component of the to-be-estimated point calculated based on the global gravity field model to obtain a disturbance gravity component calculated value of the to-be-estimated point. According to the method, the low-frequency information of the disturbance gravity component is strictly correct in principle, the spectral characteristics of the disturbance gravity component are considered to suppress the grid error influence in a medium-long wave band, and the spatial bilinear technology is utilized to improve the model resolution.

The invention discloses an inertial navigation precision compensation method of a local polynomial model considering frequency domain characteristics; the method comprises the following steps: removing a low-frequency information model value of a disturbance gravity component of an observation point calculated on the basis of a global gravity field model from an observation value of the disturbance gravity component to obtain a residual value of the disturbance gravity component of the observation point; applying a spatial domain local polynomial grid algorithm based on the residual value of the disturbance gravity component of the observation point, and calculating the residual value of the disturbance gravity component of the to-be-estimated point; and combining the residual value of the disturbance gravity component of the to-be-estimated point with the low-frequency information model value of the disturbance gravity component of the to-be-estimated point calculated based on the global gravity field model to obtain a disturbance gravity component calculated value of the to-be-estimated point. According to the method, the low-frequency information of the disturbance gravity component is strictly correct in principle, the spectral characteristics of the disturbance gravity component are considered to suppress the grid error influence in a medium-long wave band, and the spatial domain local polynomial technology is utilized to improve the model resolution.

The invention provides a local gravity field modeling method and system based on ground gravity measurement data, and the method comprises the steps: collecting ground gravity observation data in a research region, carrying out the preprocessing, determining the spatial resolution of a gravity field model and the maximum expansion order of the gravity field model, carrying out the low-pass filtering of the preprocessed data, filtering out a part higher than a maximum expansion order in the ground gravity observation data to obtain filtered gravity observation data in a research area, then determining a closed boundary of the research area, obtaining an orthogonal primary function group and an optimal primary function number through calculation, obtaining an expansion coefficient of a Slepian method through calculation, consequently, obtaining a mathematical model describing the gravitational field in the research area, and finally, according to the mathematical model of the gravitational field, calculating to obtain a gravitational field signal of any point in the research area. According to the method, the problem that a classic spherical harmonic method cannot be applied in a spherical local range is solved by constructing the orthogonal basis function in the research area.

The invention relates to a method for determining the 1985 elevation reference gravitational potential of China, which comprises the following steps of constructing a combined gravitational field model, adopting the corresponding order of a GRACE/COCE gravitational field model for the first k orders, and adopting the corresponding order of an EGM2008 gravitational field model for the k-2190 orders of the combined gravitational field model, for different k values, calculating the precision of the corresponding combined gravitational field model, selecting the gravitational field model with the highest precision as an optimal combination order gravitational field model, obtaining the longitude and latitude of the target area, and calculating the elevation reference gravitational potential of the target area through the optimal combination order gravitational field model. According to the method, the combined gravitational field model is jointly constructed based on the GRACE or COCE gravitational field model and the EGM2008 gravitational field model, the short wave precision of the gravitational field model can be better improved, and the model precision is further improved. The optimal combined order gravitational field model is adopted to calculate the elevation reference gravitational potential of the target area, the elevation reference gravitational potential of China can be determined with higher precision, and effective unification of the 1985 elevation reference and the global elevation reference in China is achieved.

The invention relates to a gravity modeling method and device based on an inverse distance weighting method and a quadric surface method, computer equipment and a storage medium. The method comprises the following steps: acquiring gravity modeling data from a to-be-modeled area; carrying out gravity field modeling on the gravity field modeling data by adopting an inverse distance weighting method to obtain a preliminary gravity field model and an error sequence of the preliminary gravity field model; fitting modeling is conducted on the error sequence according to a quadric surface method, and an error model of the to-be-modeled area is obtained; and compensating the error of the preliminary gravity field model according to the error model of the to-be-modeled area to obtain an error-compensated gravity field model. The method can improve the precision of the gravity field model.