Etude Des Signaux Recueillis Par Un Radar Embarque Sur Un Vehicule En Deplacement. Application a L'Interpretation Des Signaux Recoltes Par Le Radar Wisdom De la Mission Spatiale Exomars

TL;DR

This paper analyzes signals received by the WISDOM radar instrument on the ExoMars Rover, focusing on how rover movement and antenna orientation affect measurements, to improve subsurface exploration accuracy on Mars.

Contribution

It introduces a simulation method to model rover displacement and antenna orientation effects on radar signals for planetary subsurface studies.

Findings

Displacement of the rover influences signal measurements.

Antenna orientation affects the received signal quality.

Simulation results help correct measurement disturbances.

Abstract

The ExoMars mission of the program Aurora (ESA) aims to send a vehicle (Rover) on Mars in 2013. Beyond the technological aspects of the mission, the Rover will also carry scientific instruments for the analysis of Mars subsurface to search traces of past or present life in the Martian soil. The Rover will embark a drilling machine which will give access to samples of sub-surface of Mars to 2 meters depth. This constitutes the great originality of ExoMars, because the Mars sub-surface remains still unknown and seems to be the best place to shelter good conditions to create life. This drilling machine will be guided by a radar system sounder UHF, the WISDOM instrument, which will also make possible to probe the Mars sub-surface to a few meters of depth to detect water and to study the geological structures. We have analytical and numerical electromagnetic models to simulate the behavior of an electromagnetic wave in the Mars sub-surface, but also to simulate the interactions between the wave and the structure of the Rover. The objective of the work which we present consists in the study of the factors able to create disturbances of measurements in order to correct the effects on the measured signal. Initially we present the solution which we retained in order to be able during the same calculation to simulate the displacement of the Rover on several tens of meters. We also present the results relating to the effect of the orientation of the antenna during displacement due to topography of the observation site.