Title of dissertation: Pointing, Acquisition, and Tracking Systems for Free-Space Optical Communication Links: Tzung-Hsien Ho Doctor of Philosophy, 2007 Dissertation directed by: Professor Christopher C. Davis Department of Electrical and Computer Engineering Pointing, acquisition, and tracking (PAT) systems have been widely applied in many applications, from short-range (e.g. human motion trac...

We analyze the outage probability of integrated ground-air-space free-space optical (FSO) communication links for different atmospheric turbulence channel models. The performance ground to high altitude platforms (HAPS), HAPS geostationay Earth orbit (GEO) satellite, and GEO satellite is investigated various link configurations (downlink, horizontal, uplink) parameters such as zenith angle, sta...

Relay-aided free-space optical (FSO) communication systems have the ability of mitigating adverse effects link disruption by dividing a long into several short links. In order to solve relay selection (RS) problem in decode and forward (DF) relay-aided FSO system, we model scheme as Markov decision process (MDP). Based on dueling deep Q-network (DQN), DQN-RS algorithm is proposed, which aims at...

Mode division multiplexing (MDM) is an emerging information transmission technique in which multiple data signals can be transmitted simultaneously on different modes of a single wavelength laser beam over free-space channel. MDM potential for the realization high-speed spectral efficient communication links future generations wireless networks. We present novel MDM-based optics (FSO) system. T...

In this paper, we investigate the transmission probabilities in three cases (depending only on legitimate receiver, depending eavesdropper, and both receiver eavesdropper) quantum key distribution (QKD) systems over free-space optical links. To be more realistic, consider a generalized pointing error scenario, where azimuth elevation angles caused by stochastic jitters vibrations platform are i...

A ground-to-air free-space optical link is studied for a hovering unmanned aerial vehicle (UAV) having multiple rotors. For this UAV, four-quadrant array of photodetectors used at the receiver to alleviate adverse effect fluctuations by enlarging field-of-view. Extensive mathematical analysis conducted evaluate beam tracking performance under random effects fluctuations. The accuracy derived an...

Free Space Optics (FSO) is a highly viable solution for high-speed wireless communication and widely preferred over radio frequency systems because of its faster data transmission, no regulatory requirements secure long-range operations. However, the capacity availability FSO optical bands are significant concern in varying atmospheric conditions. Our objective to enhance network flexibility ex...