Space - temporal and frequency - polarization variations in the electromagnetic wave interacting with the forest canopy

An object of the studies in this paper is the electromagnetic field scattered by forest canopy. The purpose of this work are experimental studies of space-time and frequency correlations of the field amplitude arising due to wave interaction with the forest canopy. As a result, in a fairly broad frequency range from 0.1 to 1.0 GHz, there were obtained field autocorrelation functions in both the frequency and time domains, as well as field cross correlation functions, with the receivers being separated along the wave propagation direction and across that both in the horizontal and vertical directions. On the basis of measured data, the major mechanisms of wave scattering by forest canopy were analyzed in both the time and frequency domains. Three main partial waves, namely, direct, lateral, and reflected from the ground ones were identified through the interference picture registered. The results obtained are of great importance for developing data processing algorithms in remote sensing regarding the forest canopies.