FoPen Man-Made Objects Detection with P-band SAR Sub-Aperture Analysis

FoPen (Foliage Penetration) SAR systems, especially those operating at low frequencies, are effective for detecting man-made objects in dense forests. This study leverages a single SAR image to distinguish between the strong volume scattering from foliage and the signals of concealed man-made objects, which are typically non-isotropic along the view angle, unlike the azimuthally invariant forest or vegetation. We propose a two-step strategy: firstly, a sliding sublook analysis maintains the azimuthal bandwidth maximally wide for each sublook, producing SAR images with reduced azimuthal resolution but varied central along-track components of the wave-vector, associated with the target’s ’aspect angle’. Secondly, a homogeneity test—specifically, the coefficient of variation—analyzes the aspect angle dimension of the SAR stack. Preliminary results using P-band datasets from the TropiSAR campaign in Paracou demonstrate the effectiveness of our approach in detecting concealed vehicles and infrastructures.