Abstract: Interest in through-wall imaging has been surging for about a decade. Earlier work in this domain focused on simulations and modeling. This paper explores the potential of using Wi-Fi signals and recent advances in MIMO communications to build a device that can capture the motion of humans behind a wall and in closed rooms. The objective of this paper is to enable a see-through-wall technology that is low-bandwidth, low-power, compact, and accessible to non-military entities. To this end, the paper introduces Wi-Vi, a see-through-wall device that employs Wi-Fi signals in the 2.4 GHz ISM band. Wi-Vi limits itself to a 20 MHz-wide Wi-Fi channel, and avoids ultra-wideband solutions used today to address the flash effect. It also disposes of the large antenna array, typical in past systems, and uses instead a smaller 3-antenna MIMO radio. More than a decade of research in the field of thermal, motion, vibration and electromagnetic radiation energy harvesting has yielded increasing power output and smaller embodiments. In this paper we have introduced Vibration Energy Harvesting (VEH).ie. The energy produced due to vibrations are converted into electricity.

Keywords: Seeing Through Walls, Wireless, MIMO, Gesture Based User Interface, Electrostatic converters, VEH, Electrets.