Abstract：The effect of microwave radiation on vegetation is important for identification of land parameters. Because of complexity of vegetation, it is a difficult topic for research. This paper reviews the simulation of the vegetation canopy in passive microwaves. Various vegetation canopy models are discussed and compared. They can be grouped into 3 types. In the first type, the vegetation is considered as a uniform layer with constant opacity or albedo and simple formulas or empirical relationships can be used for computation. The other two models differ in the way the canopy is defined. In one of them, the medium is still considered as continuous but with correlation lengths. The other model uses a discrete characterization of the medium (lengths and orientations of the elements such as stalks and leaves).
2009, Vol. 27 
