Predictions of microwave attenuation through vegetation: a comparison with measurements

Attenuation over forested areas can be predicted by the physical scatter models employed in remote sensing. This paper deals with the validation of two such scatter models. The attenuation data were collected through a small scale radar experimental campaign at 2.2 and 5.8 GHz, performed June 1996 and March 1997, in the ERABLE project where the objective was, apart from validating predictions against measurements, to assess whether scatter models are useful to predict radio link performance in a forest environment. Our models of choice were the Michigan Microwave Canopy Scattering model MIMICS and one developed by Karam et al., and the forest site was a 20-year old oak stand and a 6-year old pine stand in the Fontainebleau forest, 60 km SE of Paris. Besides radar measurements of the stands, environmental parameters were collected through ground measurements, including geometrical and electromagnetic ones. These parameters were used as the input to numerical codes to simulate summer (leafy) and winter (not leafy) conditions. The agreement between the measured and the predicted data is discussed.