A study on the electromagnetic propagation in various\ud models of the Martian subsurface is performed with a relevance\ud to ground penetrating radar (GPR) operating onboard\ud rover missions. Measurements of the electromagnetic properties of\ud Mars soil simulants are obtained; on this basis, the attenuation\ud features of the GPR signals are estimated, including both electric\ud and magnetic losses. The effect on propagation of inhomogeneities\ud inside the soil is also taken into account by means of a specific\ud model with randomly distributed scatterers. The GPR performance\ud in terms of resolution and maximum penetration depth\ud is evaluated in the considered scenarios for different operating\ud frequencies, thus providing a basic information for the design of\ud systems for future subsurface sounding investigations on Mars

[1] In this paper a set of frequency domain (500 Hz to 1 MHz) experimental data on electrical and magnetic parameters of magnetite/silica mixtures as Martian soil simulants is presented. Complex permittivity was obtained by measuring the magnitude and phase of the electrical impedance of a capacitive cell filled with the tested material. Complex magnetic permeability was obtained by measuring the impedance of a toroid fully embedded in the mixtures. Both the permittivity and magnetic permeability exhibited an appreciable increase with the magnetite volume fraction and a complex behavior with grain size and origin. Furthermore, to assess the possibility of extending the data acquired at 1 MHz to higher frequencies (tens to hundreds of MHz), some comparisons were made between these data and Time Domain Reflectometry measurements. Finally, the attenuation versus magnetite volume fraction and frequency (in a band consistent with the MARSIS and SHARAD sounders) was computed for various types of magnetite/silica mixtures. The results indicate that in a dry soil which contains a significant fraction of magnetic material both the wave velocity and the attenuation are a combination of different factors, including the dimension, shape, and origin of the magnetic material.

No abstract

In this work, the effects of magnetic inclusions in a Mars-like soil are considered with reference to the electromagnetic propagation features of ground-penetrating radars (GPRs). Low-frequency and time-domain techniques, using L-C-R meters and TDR instruments, respectively, are implemented in laboratory experimental set-ups in order to evaluate complex permittivity and permeability and wave velocity for different scenarios of a dielectric background medium (silica) with magnetic inclusions (magnetite). Attenuation and maximum detection ranges have also been evaluated by taking into account a realistic GPR environment, which includes the transmitting/receiving antenna performance and the complex structure of the subsurface. The analysis and the interpretation of these results shed new light on the significant influence of magnetic inclusions on the performance of Martian orbiting and rover-driven GPRs.

No abstract