Method for conducting X wave band navigation radar wave parameter inversion through band-pass filter based on novel wave dispersion relation

Abstract

The invention belongs to the field of wave remote sensing technology, and particularly relates to a method for conducting X wave band navigation radar wave parameter inversion through a band-pass filter based on a novel wave dispersion relation, wherein sea clutter images are obtained through navigation radar so that wave parameter inversion can be conducted. The method comprises the steps that radar image data are collected; radar images are preprocessed; Fourier transform is conducted on an image sequence under a Cartesian coordinate system, so that a three-dimensional wave number frequency image spectrum of the radar images is obtained; wave spectrum information is extracted; wave information inversion is achieved. Influence on the dispersion relation by the ship speed is kept by the filter, the problem that the band pass of a traditional broadband-pass filter is increased along with increase of the movement speed is effectively solved, and therefore filtering can be conducted under the condition that a radar platform is moved along with movement of a ship. In band pass boundary derivation of the novel filter, an approximate value of any quantity is avoided, calculation errors are reduced, influence on the band pass boundary is avoided, band width calculation is more accurate, and wave inversion accuracy is improved.

Description

technical field [0001] The invention belongs to the technical field of ocean wave remote sensing, and in particular relates to an X-band navigation radar inversion method for ocean wave parameters based on a novel ocean wave dispersion relation band-pass filter, which utilizes sea clutter images acquired by navigation radars to invert ocean wave parameters. Background technique [0002] The parameters of the sea waves can be obtained by analyzing the echo images of the X-band radar. However, the echo image contains a lot of noise besides the ocean wave signal, such as frequency interference, background noise, rain and snow interference, and target echo. These noises will seriously affect the parameter inversion of ocean waves and distort the results. Therefore, it is necessary to remove these noise signals from the radar echo image and extract useful sea wave signals. Since the signal conforms to the dispersion relation of gravitational waves, the dispersion relation can b...

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Problems solved by technology

However, it can be seen from the above analysis that the approximate values ​​brought into these two filters will lead to two defects in the filter: one is only applicable to the case where the water depth is greater than or equal to one-half wavelength; The filtering effect of this filter is more accurate

In addition, the U in this filter max It will also lead to an increase in the bandwidth in the motion state, which cannot play a filtering effect

[0042] It can be seen that although the broadband filter does not need to estimate the current, the maximum expected flow rate U max It solves the problem caused by inaccurate current estimation under narrow band pass, but the band pass of the filter will be infinitely amplified under dynamic conditions, and the filtering effect cannot be achieved

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