Microwave imaging and sensing for biomedical applications

人们对个人健康监测的兴趣与日俱增，加速了生物医学传感技术的发展和完善。微波成像和传感利用低功率信号来评估与水分有关的组织的特性，并已被提议用于检测乳腺肿瘤等应用。要将这些技术从研究实验室转化为工业合作伙伴和患者，还需要进一步的开发和测试。从研究的角度来看，关键的技术挑战与硬件和成像算法有关。为了应对这些挑战，我的研究计划的长期目标是开发、实施和测试用于生物医学应用的快速、准确的微波成像和传感技术。拟议的计划有三个主题：超宽带(UWB)天线和阵列设计，改进的成像算法，以及新应用的可行性评估。*需要定制传感器来实现便携和廉价的系统。基于雷达的微波成像方法通常使用UWB信号。相应的天线是高性能和坚固的，但往往很笨重。其目标是设计低调的UWB天线和阵列，放置在与组织接触的位置以成像局部区域(例如手臂的一部分)。*生物医学微波图像旨在显示组织在毫米到厘米尺度上的分布和相应的微波频率特性。目前，基于雷达的图像以亚厘米的精度显示属性变化的位置，而微波断层成像则使用计算密集型技术创建属性地图，显示厘米级的变化。我的团队已经开发出快速方法来估计厘米级的平均房产数量。通过改进这些属性估计，我们的目标是在厘米尺度上提供组织属性和分布的信息，而不需要详细的断层扫描的计算开销。融合属性估计和雷达图像将显示异常的组织分布、属性和位置。工程分析将用于评估微波成像和传感用于几个生物医学和兽医问题的可行性。我们已经开发了一个框架来研究新的应用，包括真实模型的模拟和测试幻影的测量。这一分析支持制定有效的成像策略，例如选择频率范围。新的应用包括监测组织中的水分滞留(淋巴水肿)和评估大型动物的四肢。*影响：便携式微波成像系统、改进的算法和证明的新应用的可行性支持将微波成像从实验室转换到行业和最终用户。这项研究旨在为生物医学和兽医问题开发新的工具，并可能增强现有的工业传感技术。

Growing interest in personal health monitoring has accelerated development and refinement of biomedical sensing technologies. Microwave imaging and sensing utilize low-power signals to assess properties of tissues related to water content, and have been proposed for applications such as detecting breast tumours. Further development and testing are required to translate these technologies from research labs to industrial partners and patients. From a research perspective, key technical challenges relate to hardware and imaging algorithms. To tackle these challenges, the long term objective of my research program is the development, implementation and testing of fast and accurate microwave imaging and sensing technologies for biomedical applications. The proposed program has 3 themes: ultra-wideband (UWB) antenna and array design, improved imaging algorithms, and feasibility assessment of new applications.******Custom sensors are required to enable portable and inexpensive systems. Radar-based approaches to microwave imaging typically use UWB signals. The corresponding antennas are high performance and robust, however tend to be bulky. The goal is to design low profile UWB antennas and arrays that are placed in contact with tissues to image a localized region (e.g. part of an arm). ******Biomedical microwave images aim to indicate the distribution of tissues and corresponding microwave frequency properties on mm-to-cm scale. Currently, radar-based images indicate locations of changes in properties with sub-cm accuracy, while microwave tomography creates maps of properties showing cm-scale variations with computationally intensive techniques. My team has developed fast approaches to estimating average properties over cm-scale volumes. By improving these property estimates, we aim to provide information on tissue properties and distributions on cm-scale without the computational overhead of detailed tomography. Fusing property estimates and radar images will indicate tissue distributions, properties and locations of anomalies.*******Engineering analysis will be used to evaluate the feasibility of microwave imaging and sensing for several biomedical and veterinary problems. We have developed a framework to investigate new applications that involves simulations of realistic models and measurements of test phantoms. This analysis supports development of effective strategies for imaging, such as selection of frequency ranges. New applications include monitoring water retention in tissues (lymphedema) and assessing limbs of large animals. ******Impact: Portable microwave imaging systems, improved algorithms and demonstrated feasibility for new applications support translation of microwave imaging from the lab to industry and end users. This research aims to develop new tools for biomedical and veterinary problems, and may enhance existing industrial sensing technologies.