"Design, Calibration, and Inversion Algorithms for Novel Microwave Tomography Systems"

该研究计划的主要研究目标是提高微波断层扫描（MWT）系统的性能，用于生物医学成像应用。MWT使用微波测量来创建感兴趣对象（OI）的体电材料特性的定量图像;通常是OI的复介电常数。在生物医学应用中，OI通常是人体的原位区域，目标是使用构建的复介电常数图来识别该区域中的异常或患病组织，例如，癌组织的成像和检测。 MWT用于生物医学诊断成像的独特优势在于，重建的介电常数图不直接以任何其他方式成像，因此包含作为诊断基础的独特和互补信息。 对于生物医学应用，当前最先进的MWT系统的最大性能问题是与其他成像模式（如CT和MRI）相比有限的空间分辨率。为了成为一种可行的方式，MWT的可实现的分辨率必须增加，同时保持重建的复介电常数图的准确性。为了实现这一目标，拟议的研究将调查MWT的三个主要方面：a）用于从适当校准的散射场数据创建图像的反演算法，B）从MWT系统获取原始测量并产生用于反演算法的适当数据的校准技术，以及c）影响必须使用的电磁（EM）模型以及校准程序的MWT系统设置本身。这三个方面的MWT是相互关联的，有时微妙的方式，这是一个基本的论文，本研究提出的一个实质性的提高目前MWT成像性能只能通过这三个方面的联合研究来完成。

The main research goal of this proposed research program is to improve the performance of Microwave Tomography (MWT) systems for biomedical imaging applications. MWT uses microwave measurements to create a quantitative image of the bulk-electrical material properties of an object-of-interest (OI); typically the complex permittivity of the OI. In biomedical applications the OIs are typically in situ regions of the human body and the goal is to use the constructed complex permittivity maps to identify abnormal or diseased tissue in that region, e.g., the imaging and detection of cancerous tissue. The unique advantage of MWT for biomedical diagnostic imaging is that the reconstructed permittivity map is not directly imaged in any other modality and therefore contains unique and complementary information upon which to base a diagnosis. For biomedical applications, the greatest performance issue with current state-of-the-art MWT systems is the limited spatial resolution compared to other imaging modalities such as CT and MRI. In order to be a viable modality the achievable resolution of MWT must be increased while retaining the accuracy of the reconstructed complex permittivity maps. To achieve this goal the proposed research will investigation the three main aspects of MWT: a) the inversion algorithms used to create the images from appropriately calibrated scattered field data, b) the calibration techniques which take raw measurements from the MWT systems and produce appropriate data for the inversion algorithms, and c) the MWT system set-ups themselves which affect the electromagnetic (EM) model which must be used as well as the calibration procedure. These three aspects of MWT are interrelated, in sometimes subtle ways, and it is a fundamental thesis of this proposed research that a substantial enhancement of current MWT imaging performance can only be accomplished via the joint study of these three aspects.