Unfocused synthetic aperture radar processing of echogram data with delay and sum antenna array processing, Greenland, 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 unfocused 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_20080627_05_001.mat” contains data for a composite image from segment 05, frame 001, taken on 2008-06-27. More information can be found in “Readme.pdf”.

为更好地解析影响冰盖的各类过程，为冰盖模型提供边界条件数据，并为其他冰盖相关分析提供冰厚参数，冰盖遥感中心（Center for Remote Sensing of Ice Sheets, CReSIS）已在格陵兰岛设计、研发并部署了多台多通道雷达测深仪。本数据集的采集区域主要覆盖格陵兰岛的出口冰川周边，其中包含雅各布港（Jakobshavn）区域的大型测网，其核心目标是深化对这片冰盖动态且快速变化区域的科学认知。本产品采用非聚焦合成孔径阵列（Synthetic Aperture Array, SAR）处理技术，以提升沿轨方向的空间分辨率。用于多通道合并的阵列处理技术基于周期图法，也称作延迟求和波束成形（delay and sum beamforming）。本数据产品的存储格式为Mathworks MATLAB文件，文件命名遵循如下格式：Data{$image_id}_{$frame_id}.mat。其中{$image_id}为字符串：若对应合成图像则可留空，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并依次递增。帧ID由段ID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_20080627_05_001.mat"包含了2008年6月27日采集的段05、帧001对应的合成图像数据。更多详细信息可参阅"Readme.pdf"文档。