Focused synthetic aperture radar processing of echogram data with delay and sum antenna array processing, Greenland, July 15 - July 23, 2008

To better understand processes affecting the ice sheets and to supply boundary condition information into ice sheet models and ice thickness for other ice sheet analysis, the Center for Remote Sensing of Ice Sheets (CReSIS) has designed, developed, and deployed several multichannel radar depth sounders in Greenland. This dataset contains data collected mostly around outlet glaciers in Greenland, including a large grid at Jakobshavn, with the specific purpose of improving understanding in this dynamic and fast changing part of the ice sheet. This product uses focused synthetic aperture array (SAR) processing to improve resolution in along-track. The array processing technique used to combine the multiple channels is based on the periodogram method also known as delay and sum beamforming. The data product format is a Mathworks MATLAB file. Files are named according to the format: Data{$image_id}_{$frame_id}.mat. The {$image_id} is a string which may be empty when it is a composite image or is of the form “img_II” where II is the 2-digit zero-padded image number always starting with 1 and incrementing from there. The frame ID is a concatenation of the segment ID and a frame number and follows the format YYYYMMDD_SS_FFF where FFF is the frame number from 000 to 999. For example, “Data_img_01_20080630_02_001.mat” contains data for image 01 from segment 02, frame 001, taken on 2008-06-30. More information can be found in “Readme.pdf”.为更好地理解影响冰盖的各类过程，为冰盖模型提供边界条件信息，并为其他冰盖相关分析提供冰厚数据，冰盖遥感中心（Center for Remote Sensing of Ice Sheets，CReSIS）已在格陵兰岛设计、开发并部署了多套多通道雷达测深系统。本数据集的采集区域主要集中于格陵兰岛的出口冰川周边，涵盖雅各布港（Jakobshavn）的大型测区网格，其设计初衷是深化对这片冰盖动态且快速变化区域的科学认知。该数据产品采用聚焦合成孔径阵列（SAR）处理技术，以提升沿航迹方向的空间分辨率。用于合并多通道数据的阵列处理算法基于周期图法，该方法也被称为延迟求和波束成形（delay and sum beamforming）。本数据集采用Mathworks MATLAB文件格式进行存储。文件命名遵循如下规则：Data{$image_id}_{$frame_id}.mat。其中，{$image_id}为字符串类型，若为复合图像则可留空，否则采用"img_II"格式，其中II为两位零填充的图像编号，起始编号为1并按序递增。帧ID由段标识符与帧编号拼接而成，格式为YYYYMMDD_SS_FFF，其中FFF为取值范围000至999的帧编号。例如，"Data_img_01_20080630_02_001.mat"包含了2008年6月30日采集的段02、帧001对应的图像01的数据。更多详细信息可参阅"Readme.pdf"。