Wildfires are a recurring phenomenon in many countries around the world, either due to natural causes or negligent human behavior. Emergency communication services used by firefighters at the theater of operations must be highly reliable, in order to ensure the safety and coordination of the teams that are fighting the wildfire, contributing to extinguishing it as quickly as possible with minimum use of resources. Emergency communication networks strongly rely on wireless links that may be impaired by the flames. In this work, we present an experimental setup for characterization of fire at microwave frequencies. Preliminary results show that we are able to extract very low dielectric constant (<1.1) using ultrawideband signals. Moreover, we characterize the attenuation introduced by fire in small-scale scenario. Future
work will include the characterization of fire in larger-scale scenarios.