Model-derived synthetic aperture sonar (SAS) data in Generic Data Format (GDF)
收藏资源简介：
The simulated synthetic aperture sonar (SAS) data presented here was generated using PoSSM [Johnson and Brown 2018]. The data is suitable for bistatic, coherent signal processing and will form acoustic seafloor imagery. Included in this data package is simulated sonar data in Generic Data Format (GDF) files, a description of the GDF file contents, example SAS imagery, and supporting information about the simulated scenes. In total, there are eleven 60 m x 90 m scenes, labeled scene00 through scene10, with scene00 provided with the scatterers in isolation, i.e. no seafloor texture. This is provided for beamformer testing purposes and should result in an image similar to the one labeled "PoSSM-scene00-scene00-starboard-0.tif" in the Related Data Sets tab. The ten other scenes have varying degrees of model variation as described in "Description_of_Simulated_SAS_Data_Package.pdf". A description of the data and the model is found in the associated document called "Description_of_Simulated_SAS_Data_Package.pdf" and a description of the format in which the raw binary data is stored is found in the related document "PSU_GDF_Format_20240612.pdf". The format description also includes MATLAB code that will effectively parse the data to aid in signal processing and image reconstruction. It is left to the researcher to develop a beamforming algorithm suitable for coherent signal and image processing. Each 60 m x 90 m scene is represented by 4 raw (not beamformed) GDF files, labeled sceneXX-STARBOARD-000000 through 000003. It is possible to beamform smaller scenes from any one of these 4 files, i.e. the four files are combined sequentially to form a 60 m x 90 m image. Also included are comma separated value spreadsheets describing the locations of scatterers and objects of interest within each scene. In addition to the binary GDF data, a beamformed GeoTIFF image and a single-look complex (SLC, science file) data of each scene is provided. The SLC data (science) is stored in the Hierarchical Data Format 5 (https://www.hdfgroup.org/), and appended with ".hdf5" to indicate the HDF5 format. The data are stored as 32-bit real and 32-bit complex values. A viewer is available that provides basic graphing, image display, and directory navigation functions (https://www.hdfgroup.org/downloads/hdfview/). The HDF file contains all the information necessary to reconstruct a synthetic aperture sonar image. All major and contemporary programming languages have library support for encoding/decoding the HDF5 format. Supporting documentation that outlines positions of the seafloor scatterers is included in "Scatterer_Locations_Scene00.csv", while the locations of the objects of interest for scene01-scene10 are included in "Object_Locations_All_Scenes.csv". Portable Network Graphic (PNG) images that plot the location of objects of all the objects of interest in each scene in Along-Track and Cross-Track notation are provided.
本数据集提供的模拟合成孔径声呐（Synthetic Aperture Sonar, SAS）数据由PoSSM生成[Johnson与Brown, 2018]。该数据适用于双基地相干信号处理，可用于生成声学海底成像结果。本数据包包含以下内容：通用数据格式（Generic Data Format, GDF）文件存储的模拟声呐数据、GDF文件内容说明文档、示例SAS成像结果，以及模拟场景的辅助信息。 总计包含11个60 m × 90 m的场景，编号为scene00至scene10；其中scene00仅包含孤立散射体，即无海底纹理，该场景用于波束形成器测试，其成像结果应与「相关数据集」标签页中的"PoSSM-scene00-scene00-starboard-0.tif"文件一致。其余10个场景存在不同程度的模型差异，具体说明见《Description_of_Simulated_SAS_Data_Package.pdf》文档。 数据集与模型的详细说明见配套文档《Description_of_Simulated_SAS_Data_Package.pdf》，原始二进制数据的存储格式说明则见于《PSU_GDF_Format_20240612.pdf》。该格式说明文档还附带了可高效解析数据的MATLAB代码，用于辅助信号处理与图像重建。研究人员可自行开发适用于相干信号与图像处理的波束形成算法。 每个60 m × 90 m的场景对应4个未经过波束形成的原始GDF文件，编号为sceneXX-STARBOARD-000000至000003；仅使用其中单个文件即可生成较小场景的波束形成结果，将4个文件按顺序拼接则可得到完整的60 m × 90 m成像结果。 本数据包还包含逗号分隔值（CSV）格式的电子表格，用于记录各场景内散射体与目标对象的位置。除二进制GDF数据外，本数据集还提供每个场景的波束形成GeoTIFF图像与单视复数（Single-look Complex, SLC）科学数据。 单视复数科学数据以层次数据格式5（Hierarchical Data Format 5, HDF5）存储，文件后缀为".hdf5"，数据采用32位实数值与32位复数值格式存储。配套提供了具备基础绘图、图像显示与目录导航功能的HDF查看器（下载地址：https://www.hdfgroup.org/downloads/hdfview/）。HDF文件包含重建合成孔径声呐图像所需的全部信息，当前主流编程语言均提供HDF5格式编解码的库支持。 记录海底散射体位置的辅助说明文档见《Scatterer_Locations_Scene00.csv》，而scene01至scene10的目标对象位置则记录于《Object_Locations_All_Scenes.csv》中。此外还提供了以沿轨与交轨坐标系标注的各场景所有目标对象位置分布图，格式为便携式网络图形（Portable Network Graphic, PNG）。
