Abstract: Based on radiative transfer equation and geometric spatial model, the mechanism of the microwave radiation transfer in the inhomogeneous lunar regolith is simulated. The results indicate that low frequencies are good for the simulation on passive microwave radiative transfer in the lunar regolith. The differences of the microwave radiation brightness temperature of lunar regolith in low frequency is much bigger, and the corresponding detectable thickness is much deeper than those in high frequency for exanvples in 3 GHz, the maximum detectable thickness is up to 12.4 m. The maximum detectable thickness of lunar regolith declines drastically with the increasing of the frequency. And the detectable lunar regolith thickness in high frequency is falling into the detectable range of that in low frequency. Based on the results, a look-up table between lunar regolith thickness and brightness temperature is established. The lunar regolith thickness can be obtained from the observed single-channel brightness temperature using the look-up table.

Key words: lunar regolith thickness, brightress temperature, passive microwave remote sensing, simulation on radiative transfer, look-up table