Portable Microwave (pMWI) System for Brain Stroke Imaging Using Off-the-Shelf Components

This paper presents an upgraded version of a low-complexity microwave imaging (MWI) system for brain stroke monitoring using an off-the-shelf solid-state switching matrix, named correlator, and new optimized antenna-matching cells (Ant-MM). The new system architecture comprises a four-port transceiver made of two compact Vector Network Analyzers (VNA) in parallel, two 4-by-16 correlators, and twenty-two Ant-MMs placed on a head phantom as a helmet. The imaging consists of a qualitative linear inversion algorithm with low computing demand, running on a conventional laptop and retrieving 3-D dielectric contrast maps in real-time. As validation, the system is experimentally tested in a simplified but realistic mimicked hemorrhagic scenario using anthropomorphic phantoms, demonstrating its capability to image the stroke affection. Overall, the upgraded scanner keeps its imaging performance while reducing size at a portable or bedside patient level and data acquisition time.