Modeling the process of receiving own radiothermal radiation of the earth's surface

The receiving model of the own soil radiothermal radiation by a bipolarized microwave radiometer when remote sensing the soil moisture from an unmanned aerial vehicle on low altitude is considered. The simulation is carried out taking into account the receiving antenna pattern with side lobes. The height, speed of the carrier and the main lobe axis angle are taken into account. The main parameters of the microwave radiometer for remote determination of portraits of moistened soils are given. The Earth's surface is modeled by a two-dimensional distribution function of the soil permittivity on the thickness of the near-surface layer and a deeper layer with a different permittivity value. The two-dimensional permittivity distribution function represents as "checkerboard" with a periodic change in the permittivity of the soil by "cells". Both the proper radiothermal radiation of the soil and the relict sky radiation of the celestial sphere, re-reflected by the earth's surface, are taken into account. The perspective of using the simulation results to optimize the parameters of the radiometer and remote sensing system according to the criterion of maximum sensitivity of the system to variations in soil moisture content is analyzed.