540 
4 - SUMMARY AND FINAL REMARKS 
Microwave emission characteristics of wheat and alfalfa crops have been investigated with field 
measurements at 37 GHz aiming at detecting and quantifying the contribution of single plant 
constituents and eventual anisotropic effects. 
The results have shown that microwave emission from wheat in the flowering stage is significantly 
affected by ears. All the single plant elements have an intrinsic anisotropic emission behavior 
which is smoothed by the geometrical distribution of the plants in the field and by multiple 
scattering. On the contrary, in the case of alfalfa, emission from plants, which are characterized 
by small quasi circular leaves and ramified structure, and from single plant elements was found 
almost isotropic. 
AKNOWLEDGMENTS 
This work has been partly supported by the Italian Space Agency (ASI) 
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