RIA: Buried Object Detection with Synthetic Aperture Radars

9409890韩本课题的目标是为合成孔径成像技术开发一种改进的数据解释算法。在地物成像相干聚焦算法中，提出了一种检索介质属性的复合方案。最终目标是建立一个通用而可靠的微波成像系统，可用于检测嵌入在分层随机介质中的目标。介绍了该方法在土木工程结构的钻地作业和无损评价中的应用。在该系统中，承载主机介质属性信息的数据和承载嵌入式目标属性信息的数据同时采集，但分别进行处理。为了达到这个目的，设计了一个两阶段的数据处理方案。首先，局部目标和分层结构产生的信号的空间光谱之间的区别将被用作将信号与宿主介质隔离的机制。然后，提取的主体材料信息将用于成像算法，为来自目标的信号提供正确的相位补偿。研究内容包括：(1)地表回波隔离，(2)地下剖面反演，(3)模型在信噪预测中的应用，(4)成像算法的发展，(5)目标检测方案的构建，(6)实验。＊＊＊

9409890 Han The objective of this program is to develop an improved data interpretation algorithm for the synthetic aperture imaging technique. A composite scheme for retrieving the host medium property is integrated into the coherent focusing algorithm for buried object imaging. The final goal is to establish a general yet reliable microwave imaging system that can be used for inspecting targets embedded in stratified random media. Applications to ground-penetrating operations and nondestructive evaluation of civil engineering structures are addressed. Under this system, data carrying information on the property of the host medium and that of embedded targets will be acquired concurrently but processed separately. A two-stage date processing scheme is designed to achieve this purpose. First, the distinction between the spatial spectra of signals produced by localized targets and that by stratified structures will be used as the mechanism for isolating the signal from the host medium. Then, the extracted information on the host material will be used in the imaging algorithm to provide the correct phase compensation for signals from the targets. The following studies are included: (i) surface echo isolation, (ii) subsurface profile inversion, (iii) model application to signal and noise prediction, (iv) development of imaging algorithm, (v) construction of target detection scheme, and (vi) experiments. ***