A Method of Retrieving Sea Wind Direction from Navigation Radar Image Based on Adaptive Reduction Operator

Abstract

The invention discloses a method for inversion of an ocean surface wind direction through navigation radar images on the basis of a self-adaptation diminishing operator. The method includes the following steps that N navigation radar images are collected to form a navigation radar image sequence; median filtering is carried out on the navigation radar images; azimuth normalization is carried out on the navigation radar images after median filtering, and the line number of the azimuth of each filtered navigation radar image is fixed; global low-pass filtering is carried out on the navigation radar images after azimuth normalization to obtain ocean surface static feature images containing wind streaks; according to the ocean surface static feature images, ocean surface wind direction inversion is carried out to obtain an ocean surface wind direction. A self-adaptation algorithm is designed, whether diminishing resolution and the size of the wind streaks are proper can be judged according to judgment parameters obtained through calculation of diminished images, and inversion precision of the ocean surface wind direction is improved.

Description

technical field [0001] The invention belongs to the technical field of sea surface wind direction remote sensing, in particular to a navigation radar image inversion method based on an adaptive reduction operator. Background technique [0002] Sea surface wind field information is an important parameter of ocean dynamics, mainly including wind direction and wind speed information. Therefore, understanding and mastering sea surface wind direction information has far-reaching significance. There are two types of existing methods for measuring sea surface wind direction information: site-based on-site measurement and remote sensing measurement. Navigation radar is a kind of remote sensing measurement method. Because of its advantages of not being affected by light and weather, real-time continuous feedback, high resolution and convenient use, it has become an important means of obtaining sea surface wind direction information at this stage. [0003] At present, there are two m...

AI Technical Summary

Problems solved by technology

However, the scale of the wind stripes is between 200 and 500m, and the fixed number of reductions leads to the reduction resolution not necessarily in the appropriate range of the wind stripes, resulting in a large amount of experimental data that cannot be applied

The ratio of the resolution to the wind stripes is within a range, and the scale of the wind stripes will change according to different sea conditions. It is difficult to find a suitable ratio resolution to the scale of the wind stripes, which will also lead to the accuracy of the sea surface wind direction obtained by inversion. reduce

Therefore, the traditional local gradient method is difficult to meet the requirements of the project, and it is necessary to design a method that can adjust the reduction times and resolution according to different wind stripe scales

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