Retrieving rainfall fields through tomographic processing applied to radio base network signals

As shown in the past years by researchers at the University of Florence, rainfall rate can be estimated in real time by means of tomographic processing applied to power attenuation measurements made simultaneously along microwave links. In this paper, we focus on the possibility to exploit the 'opportunity signals' provided by radio-base station networks for mobile communication systems. We describe a new tomographic algorithm that has been specifically developed for such kind of networks in urban areas, where a high number of microwave connections is typically possible. We describe the performance of the algorithm after having tested it on a 2 hours simulated rainfall event based on a sequence of real weather radar observations and on three kind of link networks, symmetric with lower link density and asymmetric with lower and higher density. We considered 12 GHz for the test carrier frequency of the radio-base network.