Impact of Plant Row Orientation on Sentinel-1 Backscatter Time-Series of Agricultural Fields

Abstract

In this work, an attempt was made to determine trends in backscatter variation due to row orientation for four crop types: winter wheat, spring barley, rapeseed, and corn. An averaged backscatter from the fields of three study areas with different geographic locations was considered over 5 years (2017-2021) by considering ascending/descending orbits and different phenological groups. The results of this study indicate that VV polarization is higher when the SAR signal is directed perpendicular or parallel to the rows of winter wheat, barley, and canola (at a 0°, 90° aspect angle) and lower at 45° (90° scale). For a 10° difference in aspect angle, variation in VV was observed at one standardized unit for spring barley and winter wheat. The trend has been observed for all considered study areas, thus validating our observations.