19 research outputs found
Statistical Modeling of FSO Fronthaul Channel for Drone-based Networks
We consider a drone-based communication network, where several drones hover
above an area and serve as mobile remote radio heads for a large number of
mobile users. We assume that the drones employ free space optical (FSO) links
for fronthauling of the users' data to a central unit. The main focus of this
paper is to quantify the geometric loss of the FSO channel arising from random
fluctuation of the position and orientation of the drones. In particular, we
derive upper and lower bounds, corresponding approximate expressions, and a
closed-form statistical model for the geometric loss. Simulation results
validate our derivations and quantify the FSO channel quality as a function of
the drone's instability, i.e., the variation of its position and orientation.Comment: This paper has been submitted to ICC 201
Optimal Photodetector Size for High-Speed Free-Space Optics Receivers
The selection of an optimal photodetector area is closely linked to the
attainment of higher data rates in optical wireless communication receivers. If
the photodetector area is too large, the channel capacity degrades due to lower
modulation bandwidth of the detector. A smaller photodetector maximizes the
bandwidth, but minimizes the captured signal power and the subsequent
signal-to-noise ratio. Therein lies an opportunity in this trade-off to
maximize the channel rate by choosing the optimal photodetector area. In this
study, we have optimized the photodetector area in order to maximize the
channel capacity of a free-space optical link for a diverse set of
communication scenarios. We believe that the study in this paper in general --
and the closed-form solutions derived in this study in particular -- will be
helpful to maximize achievable data rates of a wide gamut of optical wireless
communication systems: from long range deep space optical links to short range
indoor visible light communication systems