Attenuation of Spruce, Pine, and Deciduous Woodland at C-Band

The presence of vegetation in the radio path significantly attenuates centimeter and millimeter radio waves. The attenuation depends on the type of vegetation, its density, the season, and the frequency. Attenuation models exist for the horizontal path through vegetation and the slant foliage path through roadside trees. In this study, slant foliage paths through roadside woodland are investigated. This letter presents results for the slant path attenuation loss at 5.2-GHz C-band frequency at three elevation angles (20
$^{\circ}$
, 40
$^{\circ}$
, and 60
$^{\circ}$
) and three types of vegetation (spruce, pine, and deciduous woodland). Differences between horizontal and slant path results are discussed, and cumulative distribution statistics of the attenuation in the various vegetation types are given.