Humans have a multitude of electrical properties that can be
measured, such as vital signs (e.g., EKG). In this paper, we
estimate impedance profiles of users at different frequencies,
by using recently proposed SFCS techniques [26]. The
advantage of SFCS is that it is trivial to instrument devices,
as only a single electrode and wire are needed. Furthermore,
it is inexpensive, and it does not require user to wear
or hold any additional devices. We are not aware of previous
attempts to explore SFCS for user identification.