Privacy-preserving wireless-based human imaging
technologies attract much attention in academia and industry.
They can serve in surveillance, security inspection, and health
monitoring, while preventing the privacy leakage from current
camera-based surveillance system. However, previous solutions
either requires dedicated hardware or costly infrastructure deployment, which hurts their practicality. In this paper, we propose
WiImage, a low-cost, instantly-deployed sensing system that can
capture a fine-grained human image and infer his contour using
ubiquitous WiFi. WiImage is free of pre-training or placing any
marker on a user’s body. WiImage consists of two technical
components. First, a lightweight multipath resolution algorithm
exploit the spatial and temporal correlation of WiFi packets
to address the multipath and extract reflected signals from a
human body. Second, an imaging algorithm infers the contour of
a human from WiFi reflections. We prototype WiImage using offthe-shelf WiFi chips and conduct experiments in several typical
indoor settings. The results show that WiImage can recover
a representative human figure and use it to identify the user
precisely.