星载SAR图像的稻田耕地系数实验研究

农田线性地物在SAR图像上的夸大表现,对基于SAR图像进行的农作物面积精确量算会产生一定的影响。本研究利用SAR图像提取了稻田沟渠、道路及田埂等线性地物,在实地和图像上分别进行了大量的测算,分析了图像上的夸大与相对方向角之间的关系,计算了线性地物半波亮度宽度的概率分布,以及稻田线性地物的耕地系数,为精确量算稻田面积提供了科学依据,并对进一步研究提出了建议。

EXPERIMENTAL RESEARCHS ON THE CULTIVATION LAND COEFFICIENT FOR RICE FIELD MAPPING WITH SAR IMAGES

Researches have demonstrated that the linear features of the cultivation land usually have exaggerative appearance on SARimages, which will affect the accuracy of crop mapping on SARimages. In this study, the authors measured lots of widths at the half brightness of linear features such as channels, dykes, roads and ridges in rice fields on SARimages, and then made comparisons with results of field investigation. On such a basis, the probability distribution of widths at half brightness of linear features and the cultivation land coefficients for rice field mapping were calculated, which could give necessary correction and hence improve accuracy in rice area mapping. Some suggestions for further researches are also put forward.