Studying the heterogeneity of the lunar regolith at Chang’E-4 landing site. Both the radar observation and the simulation were normalized with their peak value for the surface reflection echo. (A) The relative error (%) between the radar simulation and observation is a function of the disturbance range (DR) for the radar trace of 8190. The minimum relative error is at the DR of ~0.21 m. (C) Comparison between the radar simulation and averaged observation. The modeling simulation with the disturbance range is ~0.21 m. (D) The statistical result of the disturbance range whose median value is ~0.19 m and with a 1σ standard deviation of ~0.07 m.