Capacitive Sensor for Tagless Remote Human Identification Using Body Frequency Absorption Signatures

Although useful for many applications, the practical use of tagless remote human identification is often hampered by privacy, usability, reliability, or cost concerns. In this paper, we explore the use of capacitive sensors, which appear to address most of these concerns, to identify different persons based on the unique electric and dielectric properties of their bodies given by their specific tissue composition. We present experimental results obtained by measuring the capacitance of a $16~\text {cm}\times 16~\text {cm}$ transducer plate 70 cm in front of different human bodies at different frequencies in the 5–160-kHz range. The measurements show clearly distinct signatures of capacitance variation with frequency for each person in the experiment, even after accounting for capacitance variations due to different body masses or physical dimensions. This paper focuses on the contactless identification of human body using capacitive sensors in smart home environments.