Models of plant motion based on observations
(1) Cranfield University, School of Engineering, Building 52, MK43 0AL, Bedford, United Kingdom
A limiting factor in many applications of SAR interferometry is the loss of coherence due to vegetation. Over short timescales this is mostly due to motion of vegetation in natural wind.
We present data of observed plant (wheat) motion in wind from a growing season in England. Models have been fitted to these data to parameterize the plant motion for single-scattering in a general bi-static radar configuration. The model allows plant motion to be estimated much more realistically than existing assumptions of either no motion or total loss of coherence. When coupled with wind statistics and a suitable scattering model realistic estimates of loss of coherence are obtained for any radar wavelength. The models can be generalized to crops other than wheat.
Result suggest that assumptions of either no motion or of total loss of coherence from vegetation are not realistic and that significant partial coherence is often likely.
Keywords: ESA European
Space Agency - Agence spatiale europeenne,
observation de la terre, earth observation,
satellite remote sensing,
teledetection, geophysique, altimetrie, radar,
chimique atmospherique, geophysics, altimetry, radar,