文献类型：期刊文献

英文题名：Forest height retrieval using P-band airborne multi-baseline SAR data: A novel phase compensation method

作者：Lu, Hongliang[1,2] Zhang, Heng[1] Fan, Huaitao[1] Liu, Dacheng[1] Wang, Jili[1] Wan, Xiangxing[3] Zhao, Lei[3] Deng, Yunkai[1] Zhao, Fengjun[1] Wang, Robert[1,2]

第一作者：Lu, Hongliang

通信作者：Fan, HT[1];Liu, DC[1]

机构：[1]Chinese Acad Sci, Aerosp Informat Res Inst, Space Microwave Remote Sensing Syst Dept, Beijing 100190, Peoples R China;[2]Univ Chinese Acad Sci, Sch Elect Elect & Commun Engn, Beijing 100049, Peoples R China;[3]Chinese Acad Forestry, Res Inst Forest Resources Informat Tech, Beijing 100091, Peoples R China

年份：2021

卷号：175

起止页码：99-118

外文期刊名：ISPRS JOURNAL OF PHOTOGRAMMETRY AND REMOTE SENSING

收录：;EI(收录号：20211110081971);Scopus(收录号：2-s2.0-85102379841);WOS:【SCI-EXPANDED(收录号:WOS:000644695700008)】；

基金：This work was financially supported by the National Key Research and Development Program of China (grant no. 2017YFB0502700) and the National Natural Science Fund of China (grant no. 61901442, 61901443, 61901445). We would like to thank the Research Institute of Forest Resources Information Technique, Chinese Academy of Forestry, for providing the LiDAR canopy height model over Saihanba Forest Farm, and the ESA Earth Observation Campaigns Data Project, for providing Multi-baseline airborne SAR data.

语种：英文

外文关键词：Forest 3-D structure; Phase errors compensation; Network construction; Phase gradient autofocus; SAR tomography

摘要：Synthetic aperture radar (SAR) tomography (TomoSAR) has been well-established for three-dimensional (3-D) information extraction of forests using the multi-baseline SAR data stacks. The multi-baseline SAR data stacks can be acquired by spaceborne and airborne SAR systems, but for forest scenarios, the data stacks acquired by the airborne SAR system are mostly used. Such a data stack has the advantages of short revisiting time and weak temporal decorrelation. However, due to the baseline errors (caused by the residual platform motion and the measurement errors of the navigation instruments), phase errors (PEs) will occur. PEs are independent of one track to the other, resulting in spreading and defocusing in tomographic imaging. In this paper, we proposed a novel phase compensation method named NC-PGA, which combines the methods of network construction (NC) and phase gradient autofocus (PGA) to estimate and compensate the PEs. The NC method uses the Delaunay triangulation network and beamforming to obtain an accurate elevation estimate of the selected permanent scatterers, which can be used as the prior information for subsequent processing to overcome the shortcomings of the PGA method in PEs estimation. The PGA method uses the spatial invariance of PEs in a limited area to compensate for the PE of each track. The applicability of the NC-PGA method is demonstrated using simulated data and real data. The real data contains two data stacks. The one is acquired by a full-polarization P-band airborne SAR system (developed independently by our project research team) over the study area in Saihanba Forest Farm in Hebei, China. The other one is acquired by ONERA SETHI airborne system over Paracou, French Guiana, in the frame of the European Space Agency's campaign TropiSAR. We select a test area in the study area and successfully retrieve the height of the forest, and use LiDAR data for results validation and evaluation.