UWB measurements and propagation models for snowy environments

In this paper, we present the results of the first ultra wideband (UWB) measurement campaign performed in the time domain in a snowy environment. For the purpose of addressing radiolocation and communication issues, measurements were realized with aerial RX and buried TX antennas. At first, the complete measurement set-up and the explored environments are described. Then, crude but realistic propagation models, relying on geometrical optics and further narrow-band approximations, are extended to the UWB context. This work principally concerns modelling the biases affecting the time-of-flight (TOF), and the attenuation suffered by UWB signals while propagating through the snow layer. The model parameters that were extracted from measurements prove to be in accordance with expected physical trends. These preliminary results could be advantageously taken into account in the design of future UWB systems capable of fusing communication and localization functionalities. The main application we identify is the rescue and monitoring of snow avalanche victims, based on low-cost, low data rate (LDR) UWB localizers operating below 1 GHz.