Design of a 3D ray-tracing model based on digital elevation model for comprehension of large- and small-scale propagation phenomena over the Martian surface

The aim of the scientific community, towards the investigation of solutions able to favor a futuristic human settlement on Mars, also concerns ad hoc communication systems and wireless networks to be deployed over the "Red planet." However, the state-of-the-art appears to be missing of realistic and replicable models for understanding the radio propagation over precise Martian locations. This means that performing solid simulations, rather than roughly approximated ones, is really a tough task. Thus, this paper describes the design of a 3D ray-tracing simulator based on high-resolution digital elevation models (DEMs) for the evaluation of Martian large-scale and small-scale phenomena in the S and EHF bands. First, by taking advantage of the Cole-Cole equations, we computed the complex permittivity of the JSC Mars-1 Martian regolith simulant. Then, we developed a 3D tile-based structure of the Gale crater, thanks to its DEM, and finally, we implemented a ray-tracing algorithm for outdoor environments able to trace the line of sight (LOS), the first and second reflections of a radio frequency (RF) signal between a transmitter (TX) and a receiver (RX) over the 3D structure. The results focus on estimating path losses, shadowing values, outage probability, and on the parametrization of multipath channels for selected areas and subareas, presenting heavily different morphological features, of the Gale crater. Moreover, some brief considerations about dust storms and atmosphere harmful effects on propagation will be drawn.