Exploring the Relationship Between Building Height and Sentinel-1 SAR GRD Backscatter at Pixel and Building Footprint Levels

The relationship between building height and SAR backscatter intensity has garnered increasing attention in remote sensing and urban monitoring. Sentinel-1 SAR provides high-resolution imagery capable of capturing structural details of urban landscapes. Building height is a crucial urban metric, influencing radar returns due to phenomena such as double bounce, corner reflection, shadowing, and layover effects. This study examined the relationship between building height and SAR backscatter at the pixel level using single-polarized Sentinel-1 GRD data. This study revealed an inverse relationship, with higher-height pixels showing lower backscatter values. The findings highlighted that high backscatter primarily occurs at building edges rather than rooftops, indicating the limitations of a pixel-based approach. The study suggests adopting convolution-based methods that account for spatial context for more accurate urban structure analysis.