In particular, to identify different materials, we exploit
the WiFi signals transmitting through or bypassing the object,
which result in different characteristics (i.e., absorption,
refraction and reflection) in the CSI complex values from
antennas and their differences. Additionally, we extract the
signal reflected by the object from CSI to estimate its shape
(e.g., width and height) or volume based on the finding that
the strength of the reflected signal is proportional to the
reflection area of the object.Wow, can I do this at home?