Fast interpolation method for coordinate conversion of weather radar data

Abstract

The invention provides a fast interpolation method for coordinate conversion of weather radar data, which comprises the following steps: calculating an sinc interpolation kernel table in advance according to preset interpolation kernel number and quantized displacement; calculating the coordinates under a polar coordinate system which takes the current radar as a center and corresponds to grid point coordinate values of each grid point in a uniform three-dimensional grid of a geographic coordinate system to be converted, and calculating positions of the coordinates in a uniform polar coordinate discrete grid; extracting a three-dimensional matrix data block from the given discrete stored weather radar volume scan data according to the integer part of the position value; querying three rowsof elements in the table from the sinc interpolation kernel table according to the fractional part of the position value to form column vectors shown in the description, respectively, using a three-dimensional matrix data block and the column vector shown in the description obtains a two-dimensional matrix data block; obtaining a one-dimensional column vector by using a two-dimensional matrix data block and the column vector shown in the description; the interpolation result of the current grid value is obtained by using one-dimensional column vector and the column vector shown in the description. The fast interpolation method for coordinate conversion of weather radar data improves the interpolation speed.

Description

technical field [0001] The invention relates to the field of weather radar signal and data processing, in particular to a fast interpolation method for coordinate conversion of weather radar data. Background technique [0002] The data products obtained by weather radar are usually in polar coordinates centered on the radar itself, including the distance, azimuth and elevation coordinates of meteorological targets. For the application of multiple weather radar network observations, it is necessary to build a unified coordinate system, such as a geographic coordinate system composed of longitude, latitude and altitude as a reference, and the data products obtained by each radar are transformed from their own polar coordinate system to Under the new coordinate system, it is convenient for the network puzzle of weather radar data. Since most meteorological objects, such as clouds, are spatially continuous and have many fine-scale structures, it is hoped that the interpolated s...

AI Technical Summary

Problems solved by technology

Among them, although the nearest neighbor method is fast, its accuracy is too low, and it is easy to cause the interpolated radar scatter rate to be spatially discontinuous; the linear interpolation method introduces a large smoothness to the original data before interpolation, so it is easy to lose the original scatter rate fine-scale structural features

The sinc kernel interpolation method is an interpolation method based on the Nyquist sampling theorem, which has the highest accuracy, but usually has a high computational complexity

Images