An imaging method for Chang'e-5 Lunar Regolith Penetrating Radar

The Lunar Regolith Penetrating Radar (LRPR) is an instrument that will be carried by the Chang'e-S (CE-5) lander to investigate lunar regolith. In this paper, a specific imaging method is developed to process LRPR data obtained in ground tests. We measure and subtract the 'background' from test data to reduce signal clutter, and apply the envelope velocity spectrum to estimate the propagation velocity of electromagnetic waves in regolith simulant. Then a modified pre-stack migration using Hilbert transformed signals is proposed for subsurface imaging. In this method, media absorption, spherical spread loss, and Snell's law are also taken into consideration. The modified migration clearly images the granite slates buried within 2.5m and produces cleaner results than the conventional method. The introduced algorithms prove to be robust and applicable to LRPR data.