Laser altimeter atmospheric delay range finding error correction method for land object

Abstract

The invention belongs to the technical field of laser remote sensing and particularly relates to a laser altimeter atmospheric delay range finding error correction method for a land object. The invention first deduces the theoretical relationship between the atmospheric delay error and the surface atmospheric pressure, and thus simplifies the high pressure equation. According to the altitude and atmospheric pressure of the weather station measured by the ground meteorological station, the atmospheric pressure attenuation factor of each weather station is calculated, and the attenuation model of the atmospheric pressure with the height change is established. According to the latitude and longitude of the laser foot, nearest k weather stations are The results of cross validation show that the accuracy of the atmospheric pressure space-time interpolation of the method is higher than that of the NECP-based reanalysis data calculation method, and the method provided by the invention is of great value in the measurement accuracy improvement of the laser altimeter satellite.

Description

technical field [0001] The invention relates to the technical field of laser remote sensing, in particular to a method for correcting atmospheric delay ranging errors when satellite laser altimeters observe land targets on the earth's surface. Background technique [0002] The space-borne laser altimeter is a new type of satellite payload placed on a low-orbit satellite platform to obtain surface elevation information. The spaceborne laser altimeter calculates the distance between the satellite platform and the ground laser footpoint by recording the transit time of the laser pulse from emission to reflection and reception; through the attitude and position of the satellite platform, the plane of the measured ground object is calculated and elevation three-dimensional coordinates. Atmospheric delay ranging error refers to the laser pulse transmission delay caused by the uneven refractive index of the atmosphere when the laser pulse passes through the earth's atmosphere, whi...

AI Technical Summary

Problems solved by technology

This method is accurate enough for the GLAS system to observe the core elements of the relatively flat Arctic and Antarctic ice sheets (the slope of 90% of the Antarctic ice sheet is less than 3:200, and the time-space linear / bilinear interpolation error of global meteorological data based on the standard pressure layer using NCEP The standard deviation of GLAS is 5hPa (corresponding to dry term delay 12mm)), but the accuracy for land targets with complex surface undulations is low (about 5cm, which has seriously exceeded the standard for the overall design accuracy of GLAS system of 15cm)

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