Measurements over Forested Areas : a Microwave Attenuation and Backscatter Experiment at 2.2 and 5.8 GHz

Interaction phenomena in the 1-10 GHz band between an electromagnetic signal and vegetation represent an interesting physical topic for all applications related to forward propagation and backscatter problems. As a matter of fact, remote sensing application aims to retrieve forest geophysical parameters by means of radar data and telecommunication services providers are very interested in attenuation prediction methods. Nowadays, satellite observations may add large scale measurements and images, nevertheless the description of absorption and diffusion mechanism takes full advantage of small scale experiment, which imply measurements over well controlled areas. ERABLE project takes place in this context. Two forest sites, respectively a pine stand and an oak one in the Fontainebleau area, have been chosen with the double objective of measuring forest backscatter coefficient and vegetation induced attenuation. Two measurement campaigns, performed at two frequencies (2.2 and 5.8 GHz) and two polarizations (HH and VV) over those areas have given a database useful to compare results given by two prediction models with experimental data. Winter and summer campaign has been set up in order to observe, if any, seasonal effects and to quantify leaves attenuation contribution on deciduous trees.