Comparing Aerial-RIS- and Aerial-Base-Station-Aided Post-Disaster
Cellular Networks
Abstract
Reconfigurable intelligent surface (RIS) technology and its integration
into existing wireless networks have recently attracted much interest.
While an important use case of said technology consists in mounting RISs
onto unmanned aerial vehicles (UAVs) to support the terrestrial
infrastructure in post-disaster scenarios, the current literature lacks
an analytical framework that captures the networks’ topological aspects.
Therefore, our study borrows stochastic geometry tools to estimate both
the average and local coverage probability of a wireless network aided
by an aerial RIS (ARIS); in particular, the surviving terrestrial base
stations (TBSs) are modeled by means of an inhomogeneous Poisson point
process, while the UAV is assumed to hover above the disaster epicenter.
Our framework captures important aspects such as the TBSs’ altitude, the
fact that they may be in either line-of-sight or non-line-of-sight
condition with a given node, and the Nakagami-m fading conditions of
wireless links. By leveraging said aspects we accurately evaluate three
possible scenarios, where TBSs are either: (i) not aided, (ii) aided by
an ARIS, or (iii) aided by an aerial base station (ABS). Our selected
numerical results reflect various situations, depending on parameters
such as the environment’s urbanization level, disaster radius, and the
UAV’s altitude.