Wave parameter acquisition method based on SAR image refocusing of sea surface undulation moving target

Abstract

The invention provides a wave parameter acquisition method based on sea surface fluctuating target SAR image refocusing. The SAR image of a target area is acquired, and a refocusing algorithm based on inverse transformation and ISAR motion compensation is applied to the data of the SAR image including a motion target sub-image so that the focused SAR image and a phase error compensation curve corresponding to the image are obtained; and the phase error compensation fitting curve of the form of the sine function is combined with the phase error expression in a wave fluctuation motion model to perform corresponding analysis so that the motion amplitude and the period of the fluctuating motion target can be obtained, and the wave height and the period and other parameters can be inferred according to the motion amplitude and the period of the fluctuating motion target. The processing procedure is simple and rapid, the cost is low and the result is accurate, the method has the advantage of data analysis and processing, and only a light and small buoy requires to be placed in a measurement area so that the monitoring mode is simple and easy to implement, coastal information can be accurately measured and area occupation is small without limitation of the sea area.

Description

technical field [0001] The invention belongs to the field of ocean remote sensing information extraction and synthetic aperture radar signal processing, in particular to the field of ocean remote sensing ocean wave information extraction and synthetic aperture radar data fine processing, and relates to a method for acquiring ocean wave parameters based on refocusing of SAR images of undulating sea surface moving targets. Background technique [0002] In the study of marine dynamic environment, ocean waves are an important element and an important parameter in oceanographic research. Therefore, predicting and obtaining information on ocean waves has a very close relationship with marine military technology and maritime safety navigation, and is of great scientific importance. significance and practical value. [0003] The existing ocean monitoring methods mainly include traditional methods such as buoys and submarine buoys, and emerging radio telemetry methods such as satelli...

AI Technical Summary

Problems solved by technology

Satellite telemetry has the advantages of global coverage, but the detection period is long and the resolution is low; microwave shore-based radar has high resolution and can provide relatively comprehensive wave and current information with high accuracy. A large number of important waterways and other places have been deployed, but due to the large propagation attenuation, its detection distance is limited, generally only within a few kilometers, which is difficult to meet the monitoring of medium and long-range marine environments; the passive radiation radar based on GNSS developed in recent years can detect Sea surface wind field and wave field, but the detection distance and area are limited, so it has certain limitations; shore-based high-frequency ground wave radar can overcome the above difficulties, and can not only provide large-area data, but also provide continuous time series Wave, current and sea surface wind speed data, but its cost is high, the antenna covers a large area, and more importantly, there is a large blind area for the near-shore area, and it is difficult to obtain important information about the waves within a few kilometers of the near-shore

[0004] Therefore, in general, the following technical problems still exist in the field of ocean remote sensing wave information extraction: cumbersome processing methods, inability to accurately obtain near-shore information, high cost, large antenna footprint, and limited detection distance, etc.

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