A Wearable Wrap-Around Sensor for Monitoring Deep Tissue Electric Properties

A wearable wrap-around sensor is proposed for continuous measurement of the permittivity of biological tissues deep into the torso (specifically, lung, and heart). The sensor is composed of multiple electrodes (antennas), excited at a single low frequency. A postprocessing technique is applied to the scattering data received by the electrodes to extract the permittivity of the tissues. The extraction process, which suppresses interferences from skin, fat, muscle, and bone layers is important especially with the fact that electrical properties may deviate from one person to another. In addition, the physical layout of the sensor provides the means to excite specific segments in a manner that localizes the extracted dielectric constant. This capability can allow for rudimentary localized imaging of the torso´s cross section and different regions of the body using a low-cost portable sensor.