Flood detection method based on SAR (Synthetic Aperture Radar) image

Abstract

When natural disasters such as flood occur, a monitoring area is often influenced by factors such as clouds and rainfall along with severe weather, and optical remote sensing is difficult to play a role. As an active microwave imaging sensor, the SAR becomes one of main means for current earth observation due to the unique technical advantages of all-day, all-weather, long operating distance and the like, first-hand remote sensing image information of a monitored area can be rapidly obtained under the severe meteorological condition, and an important basis is provided for disaster reduction and relief decision making. However, in the aspect of SAR flood disaster area water body information extraction, a common method is carried out based on fully-polarized SAR data, but the acquisition amount of the fully-polarized SAR data is limited, and the rapid response requirement of disaster emergency cannot be met often. Moreover, many difficult problems exist in SAR image water body extraction, for example, a shadow formed by a mountain body and the like has similar gray level characteristics with a water body on the image, and serious false alarms can be brought to accurate extraction of the SAR image water body area. The defects in the prior art are overcome, the flood detection method based on the SAR image is provided, the flood submerging area and distribution of the lake area can be rapidly and accurately obtained, and the false alarm phenomenon caused by weak scatterers such as mountain shadows to water extraction can be reduced.

Description

technical field [0001] The invention belongs to the field of microwave imaging, and in particular relates to a flood detection method based on SAR images. Background technique [0002] When natural disasters such as floods occur, it is often accompanied by severe weather, and the monitoring area will be affected by factors such as clouds and precipitation, making it difficult for optical remote sensing to play a role. As an active microwave imaging sensor, SAR has become one of the main means of earth observation due to its unique technical advantages such as all-weather, all-weather, and long range. It can also quickly obtain monitoring areas under severe weather conditions. First-hand remote sensing image information provides an important basis for disaster reduction and relief decisions. my country is a country prone to flood disasters, and flood disasters often occur in July and August every year. Therefore, realizing rapid detection of water bodies in flood-affected a...

AI Technical Summary

Problems solved by technology

However, in the aspect of water body information extraction in SAR flood disaster areas, the commonly used method is based on full-polarization SAR data, but the acquisition of full-polarization SAR data is limited, and often cannot meet the rapid response requirements of disaster emergency

Moreover, there are many difficulties in water body extraction in SAR images. For example, the shadows formed by mountains and other water bodies have similar grayscale characteristics on the image, which will bring serious false alarms to the accurate extraction of water body areas in SAR images.

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