  In communication-denied or contested environments, Line-of-Sight (LoS)
communication (e.g free space optical communication using infrared or visible
light) becomes one of the most reliable and efficient ways to send information
between geographically scattered mobile units. In this paper, we consider the
problem of planning optimal locations and trajectories for a group of
autonomous vehicles to see a set of units that are dispersed in an environment
with obstacles. The contributions of the paper are the following: 1) We propose
centralized and distributed algorithms to verify that the vehicles and units
form a connected network through LoS; 2) We present an algorithm that can
maintain visibility-based connectivity, if possible, by relocating a single
vehicle; and 3) We study the computational
