I am pleased that a paper titled “Advances in Microwave Near-Field Imaging” has been published in IEEE Microwave Magazine, in 2020, that I am a co-author on. This paper is a review paper of known near-field microwave imaging systems until late 2018. One of the systems reviewed is the one I worked on with the Celadon Research Division of Ellumen Inc. that was described in the paper titled “A Time-Domain Measurement System for UWB Microwave Imaging” which published in IEEE Transactions on Microwave Theory and Techniques, in 2018. The paper appearing in IEEE Microwave Magazine is particularly focused on recent active mode systems for early stage breast-cancer and brain-injury detection. Active mode is where microwave radiation is directed towards tissue, and the scattered electromagnetic fields are detected and processed. The paper also explores nondestructive testing using microwave-imaging techniques including through-the-wall imaging and security screening applications.
Based on a thorough review of the systems, the paper also offers an outlook of using microwave imaging in the future. Microwave imaging for medical applications has attracted significant interest which is expected to continue due to technical developments and improvements in hardware manufacturing and software. Vector network analyzers and oscilloscopes that have longed been used in experimental systems are starting to become replaced by more compact and cost effective instruments which will help with future commercial products. Decreases in system cost and size is to be expected moving forward. It is believed that microwave imaging techniques will be expanded to additional clinical applications and clinical trials will help lead the way towards use in patient care utilizing this technology.
I have included an excerpt from the accepted version of the paper below. DOI: https://doi.org/10.1109/MMM.2020.2971375 © 2020 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.
Table 2 in the paper offers a comparison of three microwave brain-imaging detection systems. It is noteworthy that the frequency used by the three groups is typically lower than that found for comparable breast-imaging systems. This is because brain tissue is more lossy to microwaves than breast tissue and thus a lower frequency allows for more energy to enter the brain. One of the microwave brain-imaging detection systems is developed by EMTensor and detects strokes. This system was previously exhibited on the floor of the Radiological Society of North America’s (RSNA) 104th Scientific Assembly and Annual Meeting at McCormick Place in Chicago, IL, in 2018.