Fig. 2. Radar profiles representative of a low root biomass transect (control) and a high root biomass transect (irrigated). The midpoint of each image is the location of the row center, tapering at either end to the inter-row area. Effect of each digital signal processing procedure on the profile is presented: (A) horizontal distance normalization only, (B) horizontal distance normalization, and background removal, (C) horizontal distance normalization, background removal, and Kirchoff migration, (D) horizontal distance normalization, background removal, and Hilbert transformation.