Gravitational field model-assisted inverse distance weighted geoid-like grid interpolation method

Abstract

The invention belongs to the field of surveying and mapping science and technology, and discloses a gravitational field model-assisted inverse distance weighted geoid-like grid interpolation method, which comprises the following steps of: searching four grid nodes closest to an interpolation point in a geoid-like grid numerical model; setting the geodetic coordinates of four grid nodes and geoid-like elevation anomaly according to the geoid-like grid numerical model; calculating model elevation anomalies of the grid nodes and the interpolation points according to the geodetic coordinates of the interpolation points and the searched grid nodes by using a reference gravity field model bit coefficient; substracting the model elevation anomaly from the geoid elevation anomaly of the grid points to obtain the residual elevation anomaly of the four grid nodes; according to the residual elevation anomaly of the grid node, calculating the residual elevation anomaly of the interpolation point by adopting an inverse distance weighting method; and adding the residual elevation anomaly of the interpolation point to the model elevation anomaly of the point to obtain a final elevation anomaly interpolation result of the interpolation point. The method can greatly improve the precision of the elevation anomaly interpolation result.

Description

technical field [0001] The invention belongs to the field of surveying and mapping science and technology, in particular to a gravity field model-assisted inverse distance weighted quasi-geoid grid interpolation method. Background technique [0002] At present, in engineering applications, my country uses the normal height as the legal elevation system, the quasi-geoid is the elevation datum in my country, and the normal height is the distance from the ground point to the quasi-geoid. The elevation information obtained by GNSS (Global Navigation Satellite System) technology is the geodetic height relative to the ellipsoid, and the geodetic height must be converted into normal height to be directly applied to engineering construction. The height anomaly is the distance from the quasi-geoid to the reference ellipsoid. The key problem of converting geodetic height to normal height is to obtain the height anomaly of the GNSS observation point. The geodetic height observed by GNS...

AI Technical Summary

Problems solved by technology

[0005] Through the above analysis, the existing problems and defects of the existing technology are: the existing technology is greatly affected by the trend of quasi-geoid, resulting in low accuracy of interpolation results

[0006] The difficulty in solving the above problems and defects is: due to the uneven distribution of the earth’s density and mass, the quasi-geoid is an irregular surface, which cannot be expressed by an accurate mathematical model, and any fitting and interpolation method has errors, resulting in interpolation results and There is a certain deviation from the real value

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