Monday | September 2, 2024

Near-Real-Time Inverse Scattering for Intraoperative Microwave Monitoring of Thermal Therapies

The use of microwaves for biomedical diagnostics and treatment has been a growing area of research within both the electromagnetics and healthcare communities. For example, microwave medical imaging, which in essence is a multistatic radar system, has been investigated for noninvasive and non-ionizing diagnostics. Radio frequency (RF) ablation has been used for treatment of malignant lesions. Microwave hyperthermia has been used for enhancing drug absorption and promoting healing processes.  For delivering thermal therapies, a persistent challenge is monitoring the temporal and spatial progression of heat deposition to prevent under- or over-treatment. Given the strong dependence of the permittivity of both healthy and malignant biological tissue on temperature, in the past several years our team has been investigating the efficacy of microwave imaging for monitoring of thermal treatments, especially in near-real-time for intra-operative purposes. As such, by using progressively accelerated inverse scattering methods for estimating tissue dielectric constant, we are able to map the temperature of the 3D treatment domain in near-real time. This talk will provide an overview of our recent work on microwave inverse scattering systems for the purpose of providing rapid thermal monitoring. We will describe a number of developments that have resulted in more accurate, higher-resolution, and rapid image generation, including the simultaneous use of multiple frequencies, optimization of transmit-receive measurement pairs, and the use of a convolutional neural network trained with MRI images. A sampling of results will be presented to show successful retrieval of dielectric constant and temperature fields with a precision of 1° C and spatial resolution of sub-cm at a refresh rate of about 1 frame per second, which has the promise of making this technology realistically useful in a clinical setting. 

Mahta Moghaddam is Distinguished Professor and Ming Hsieh Endowed Chair in Electrical and Computer Engineering at the Viterbi School of Engineering, University of Southern California (USC), Los Angeles, CA, USA. She currently serves as the Viterbi School Vice Dean for Research and Co-Chair of the USC President’s Working Group on Sustainability. She is also the Co-Director of the USC Center for Sustainability Solutions. Prior to USC she was at the University of Michigan (2003-2011) and NASA Jet Propulsion Laboratory (JPL, 1991-2003). She received the B.S. degree in 1986 from the University of Kansas, Lawrence, Kansas with highest distinction, and the M.S. and Ph.D. degrees in 1989 and 1991, respectively, from the University of Illinois at Urbana-Champaign, all in Electrical and Computer Engineering. Mahta’s expertise is in microwave sensing for environmental and biomedical applications. She was Systems Engineer for the Cassini Radar and served as Science Chair of the JPL Team X (Advanced Mission Studies Team). Her most recent research interests include the development of multistatic radar instrument and measurement technologies, including software-defined radar, for subsurface and subcanopy characterization, development of forward and inverse scattering techniques for layered random media especially for root-zone soil moisture, ground water, and permafrost applications, geophysical retrievals using signal-of-opportunity reflectometry, and transforming concepts of radar remote sensing to medical imaging and therapy systems. Mahta is a member of the Science Team of the Cyclones Global Navigation Satellite System (CYGNSS) mission, and the Arctic Boreal Vulnerability Experiment (ABoVE). She was the principal investigator of the AirMOSS NASA Earth Ventures 1 mission. She is a Fellow of IEEE and a member of the National Academy of Engineering.

Mahta Moghaddam, PhD

Distinguished Professor and Ming Hsieh Endowed Chair in Electrical and Computer Engineering

Viterbi School of Engineering, University of Southern California (USC), Los Angeles, CA, USA

Monday | September 2, 2024

Antenna+AI: Generative Antenna Design Reshapes Metantenna Technology

Antenna technology has a rich history dating back to the 19th century, with continuous advancements aimed at meeting the escalating demands of wireless systems development. Over the past two decades, metamaterial-based antenna technologies have emerged as a significant avenue for enhancing various antenna parameters such as bandwidth, size reduction, gain enhancement, and mutual coupling suppression. Concurrently, the rapid evolution of artificial intelligence (AI), particularly generative neural network methodologies, presents a promising frontier in antenna design innovation.

This keynote speech explores the transformative potential of deep learning (DL), a subset of machine learning (ML) within AI, in revolutionizing antenna design. The presentation begins by outlining the prospective impact of DL on antenna innovation, followed by the introduction of two design exemplars employing generative adversarial networks (GANs). These examples illustrate novel approaches to metacell design within metasurfaces, achieved through pixelization techniques and DL-driven algorithms. Notably, the incorporation of prior knowledge (PK) in DL-enabled synthesis is elucidated, showcasing its efficacy in synthesizing metacells for metalens applications.


Furthermore, the presentation showcases how metalenses synthesized using PK-DL techniques exhibit breakthrough performance and offer additional functionalities in metalens antenna design. The discourse concludes by contemplating the future trajectory of Antenna+AI integration, highlighting its potential to redefine the boundaries of antenna engineering.

Zhi Ning Chen received his two PhD degrees in 1993 and 2003, respectively. Dr. Chen has worked in academic, research organizations, and industry since 1988. He is currently a Provost Chair Professor and the Director of the Advanced Research and Technology Innovation Center at the National University of Singapore. Dr. Chen is the founding General Chair of several international workshops and symposiums, including the International Workshop on Antenna Technology (iWAT in 2005), International Symposium on InfoComm & Mechatronics Technology in Bio-Medical & Healthcare Application (IS 3Tin3A in 2010), International Microwave Forum (IMWF in 2010), Asia-Pacific Conference on Antennas and Propagation (APCAP in 2012), and Marina Forum (Mar-For in 2021). He has also been involved in many international events as a general chair, chair, and member of technical program committees and international advisory committees. He has been invited to deliver over 110 keynote, plenary, and invited speeches at international academic and industry events. Dr. Chen has published over 700 academic papers and seven books, as well as held over 36 granted/filed patents and completed over 42 technology licensing deals with industry. He is a pioneer in developing small and ultra-wideband antennas, wearable/implanted medical antennas, package antennas, near-field antennas/coils, three-dimensional integrated LTCC arrays, microwave metamaterial-metasurface antennas. Currently, Dr. Chen is focusing on the translational research of metasurfaces into antenna engineering as well as the development of algorithms, particularly machine-learning-enabled synthesis methods for metantennas. Dr. Chen is the recipient of the IEEE John Kraus Antenna Award (2021) and many other academic and engineering awards. He was elevated to the Fellow of the Academy of Engineering, Singapore in 2019, Fellow of the Asia-Pacific Artificial Intelligence Association (AAIA), and is serving as Vice President of AAIA. He was also elevated to Fellow of the IEEE for his contribution to small and broadband antennas for wireless applications in 2007. He is serving as a Member of the AdCom of the IEEE Antennas and Propagation Society (since 2023). He served on the IEEE Council on RFID as a Vice President and a Distinguished Lecturer (2015-2021), as well as on the IEEE Transactions on Antennas and Propagation as an Associate Editor (2012-2018, 2023-), and the IEEE Antennas and Propagation Society as a Distinguished Lecturer (2009-2012).

Prof. Zhi Ning Chen 

Provost Chair and Professor of ECE – National University of Singapore