Backscatter coefficient

The backscatter coefficient, often denoted as σ⁰ (sigma naught), is a normalized measure of the radar return from a distributed target. It represents the portion of the radar signal that is scattered back toward the radar sensor per unit area. This coefficient is typically expressed in decibels (dB) and is fundamental in interpreting radar imagery, especially in synthetic aperture radar (SAR) applications (American Meteorological Society, 2024).