The steady advances in light-emitting diode (LED) technology have motivated the use of LEDs in optical wireless
communication (OWC) applications such as indoor local area networks (LANs) and communication between
mobile platforms (e.g., robots, vehicles). In contrast to traditional radio frequency (RF) wireless communication,
OWC utilizes electromagnetic spectrum that is largely unregulated and unrestricted. OWC communication may
be especially useful in RF-denied environments, in which RF communication may be prohibited or undesirable.
However, OWC does present some challenges, including the need to maintain alignment between potentially
moving nodes. We describe a novel system for link alignment that is composed of a hyperboloidal mirror,
camera, and gimbal. The experimental system is able to use the mirror and camera to detect an LED beacon of
a neighboring node and estimate its bearing (azimuth and elevation), point the gimbal towards the beacon, and
establish an optical link.
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