Virtual See-Through Sensor using UWB

Detecting human presence behind rubbles can play a major role in rescue operation. However, seeing through opaque material is very challenging. In this paper, we have demonstrated such a see-through sensor using Ultra-Wideband (UWB) radio signals using the `ranging' technique. The theory behind this work is based on finding the complex permittivity of the obstructing material at least two different frequencies using UWB radio waves. Once the permittivity values of the material are found, slope of the permittivity curve can be estimated and a sensor can be deigned to `ignore/see through' the obstruction by estimating the speed of the UWB signal through it. We have experimentally verified this using an UWB transceiver equipped rescue robot that was able to detect human presence behind wood and dry-wall.