  Advancements in unmanned aerial vehicle (UAV) technology have led to their
increased utilization in various commercial and military applications. One such
application is signal source search and localization (SSSL) using UAVs, which
offers significant benefits over traditional ground-based methods due to
improved RF signal reception at higher altitudes and inherent autonomous 3D
navigation capabilities. Nevertheless, practical considerations such as
propagation models and antenna patterns are frequently neglected in
simulation-based studies in the literature. In this work, we address these
limitations by using a two-ray channel model and a dipole antenna pattern to
develop a simulator that more closely represents real-world radio signal
strength (RSS) observations at a UAV. We then examine and compare the
performance of previously proposed linear least square (LLS) based localization
techniques using UAVs for SSSL. Localization of radio frequency (RF) signal
sources is assessed based on two main criteria: 1) achieving the highest
possible accuracy and 2) localizing the target as quickly as possible with
reasonable accuracy. Various mission types, such as those requiring precise
localization like identifying hostile troops, and those demanding rapid
localization like search and rescue operations during disasters, have been
previously investigated. In this paper, the efficacy of the proposed
localization approaches is examined based on these two main localization
requirements through computer simulations.
