Ground object target detection method of low signal-to-clutter ratio synthetic aperture radar image

Abstract

The invention relates to a low signal-to-clutter ratio two-dimensional radar image target detection method. The method is characterized by through profile transformation, selecting a decomposition coefficient characteristic, restraining an influence of an inherent speckle noise of a SAR image and increasing a signal to noise ratio of the SAR image; extracting characteristic information of different directions and acquiring a target edge details and geometrical information; extracting the different decomposition coefficient characteristics so as to carry out fusion processing, improving a gap between a target characteristic value and a background characteristic value and increasing a target detection capability and a false alarm resistance capability. The invention discloses the target detection method which can be used to effectively process a low signal-to-clutter ratio SAR image; a direction decomposition number of each decomposition scale can be designed arbitrarily; detail information of a low-frequency characteristic sub-graph and a plurality of high-frequency characteristic sub-graphs can be acquired so that a small target, a hidden target and a weak scattering target which can not be detected by using a general method can be easily detected; a high false alarm resistance capability is possessed so that an inspection effect of the target is effectively increased.

Description

technical field [0001] The invention belongs to the technical field of signal and information processing, and relates to a low-signal-to-clutter ratio two-dimensional radar image target detection method which combines contourlet (Contourlet) transformation technology in multi-scale geometric analysis and synthetic aperture radar imaging technology. Background technique [0002] Synthetic Aperture Radar (hereinafter referred to as SAR) has been widely used in civilian and military fields since its birth in the early 1950s. Since SAR is an active microwave coherent imaging radar, its typical feature is the ability to acquire data all-weather and all-weather. Therefore, together with hyperspectral remote sensing, it is called the two frontier fields of contemporary remote sensing. It is an indispensable and important detection technology for space-based reconnaissance and surveillance systems. The application of SAR in the military field has very good prospects. It is not only...

AI Technical Summary

Problems solved by technology

Therefore, in remote sensing images, these targets often appear as weak scattering or weak reflectors, which are often interfered and covered by background clutter signals, making it difficult to be detected or detected

The root cause of this phenomenon is that the reflection or scattering intensity between the target and the background is very close, that is, their gray values ​​are very close, resulting in a very low signal-to-noise ratio of the entire image

This is very unfavorable for target detection and recognition

However, the existing target detection methods are difficult to obtain ideal results. Therefore, in order to effectively detect these concealed targets, weakly reflective targets and smaller targets, the present invention starts from the SAR imaging mechanism and utilizes the multi-scale geometric analysis theory. Based on the wave transform principle, a new low signal clutter ratio (LowSignalClutterRatio, LSCR) target detection method is proposed.

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