On the Use of an Electromechanical and a Solid-State Switching Matrix for a Portable Microwave-Based Brain Stroke Scanner

In this letter, we examine the effects of the switching matrix on a multiview and low-complexity portable microwave imaging system for brain stroke monitoring. It considers two switching solutions: an ad-hoc one relying on RF electromechanical switches and a compact off-the-shelf one using solid-state switches. The performed analysis deems path attenuation and interchannel isolation. It studies the impact of the different components of the scanning time, such as switching, communication, acquisition times, and the system dynamics on imaging performance and monitoring capabilities, optimizing the system setting while identifying system bottlenecks. The system uses an upgraded antenna-matching module and is experimentally validated using a mimicked hemorrhagic stroke-evolving scenario, demonstrating the effectiveness of both switching solutions in tracking and localizing the stroke progression. Tests of repeatability and sensitivity to false positive cases are also reported.