Thesis (M.S.)--University of Nevada, Reno, 2008. / "May, 2008." Includes bibliographical references (leaves 50-55). Online version available on the World Wide Web.

Thesis (M.S. in Computer Science)--Naval Postgraduate School, December 2002. / Thesis advisor(s): Bert Lundy, Mike Tatom. Includes bibliographical references (p. 123-125). Also available online.

Thesis (Ph.D.) - University of Queensland, 2004. / Includes bibliography.

archives@tulane.edu / Quantum nonlinear optics has opened up avenues to defy the measurement, sensing, and amplification limits inherent in classical physics. Separately, the use of multimode or spatially structured states in light-based communications allows for remarkable increases in the amount of information that may be transferred by an individual communication or light pulse. In this dissertation, we apply these two boundary-pushing concepts to several experimental projects, with a primary goal to hasten and facilitate the implementation of quantum and classical free-space optical communications schemes into real-life scenarios. We start by applying neural networks to the optimization of spatially-structured and pulsed light communications in Chapter 2, wherein our networks successfully learn to predict distorted optical pulses and classify noisy light patterns carrying non-zero orbital angular momentum. Chapter 3 focuses on four-wave mixing, a nonlinear light-matter interaction in atomic vapor that we use to construct quantum-correlated light beams with nontrivial structures as well as a novel phase-sensitive amplifier. Finally, we continue to take advantage of the complex nonlinear response of atomic vapor in Chapter 4, this time to create "self-regenerating" light beams whose cross-sections resemble Bessel-Gauss functions. / 1 / Erin Knutson

No description available.

In this thesis, the optical communication systems for millimeter-scale sensing and communication devises known as "Smart Dust" are described and analyzed. A smart dust element is a self-contained sensing and communication system that can be combined into roughly a cubic-millimeter mote to perform integrated, massively distributed sensor networks. The suitable passive optical and fiber-optic communication systems will be selected for the further performance design and analysis based on the requirements for implementing these systems. Based on the communication link designs of the free-space passive optical and fiber-optic communication systems, the simulations for link performance will be performed. / Master of Science

Free-Space Optical (FSO) communication through the terrestrial atmospheric channel offers many benefits in the wireless communications arena, like power efficiency; suitability for secure communications; absence of electromagnetic interference; and potentially very high bandwidth. An optical beam propagating through the atmosphere is subject to optical turbulence. Optical turbulence is a random process that distorts the intensity and phase structure of a propagating optical beam and induces a varying signal at the receiver of an FSO communication link. This phenomenon (usually referred to as scintillation) degrades the performance of the FSO link by increasing the probability of error. In this dissertation we seek to characterize the effects of the scintillation-induced power fluctuations by determining the channel capacity of the optical link using numerical methods. We find that capacity decreases monotonically with increasing turbulence strength in weak turbulence conditions, but it is non-monotonic in strong turbulence conditions. We show that low-density parity-check (LDPC) codes provide strong error control capabilities in this channel if a perfect interleaver is used. Multiple transmit optical beams can be used to reduce scintillation. We characterize the spatial correlation of the atmospheric optical channel and determine a scintillation model for the multiple-beam scheme. With this model we can predict the effective reduction in scintillation as a function of the system design parameters. A Multi-channel FSO communications system based on orbital angular momentum (OAM)-carrying beams is studied. We analyze the effects of turbulence on the system and find that turbulence induces attenuation and crosstalk among OAM channels. Based on a model in which the constituent channels are binary symmetric and crosstalk is a Gaussian noise source, we find optimal sets of OAM states at each turbulence condition studied, and determine the aggregate capacity of the multi-channel system at those conditions. At very high data rates the FSO channel shows inter-symbol interference (ISI). We address the problem of joint sequence detection in ISI channels and decoding of LDPC codes. We derive the belief propagation equations that allow the simultaneous detection and decoding of a LDPC codeword in a ISI channel.

Thesis (M.S.E.C.E.)--University of Delaware, 2007. / Principal faculty advisor: Michael W. Haney, Dept. of Electrical and Computer Engineering. Includes bibliographical references.

Because of the need to move large amounts of data effienciently, optical based communications are a critical component of modern telecommunications. And as a key enabler of optical communications, electrical components play a critical role in optical data links. Optoelectronic integrated circuits provide the bridge between the optical and electrical realms. Electronic integrated circuits are also integral parts of the optical link, interfacing with post processing circuitry and compensating for any limitations along the link. In this investigation, three circuits for optical data link applications are studied. Two optoelectronic integrated circuit front-ends for freespace and long haul applications, respectively and an active filter for near end cross talk cancellation associated with high data rate transmission. The first circuit is an 8x8 monolithic receiver array for a Spatial Division Multiplexing optical link. A compact and low power 8x8 array was designed and demonstrated a channel that received data at rates of 1Gb/s. It is the first completely monolithic demonstration of a 2D receiver array within a conventional ion implanted GaAs MESFET process. The second circuit demonstrated a long wavelength (1.55 m) optoelectronic receiver for long haul applications. The circuit utilized a TWA topology, which maximizes the available bandwidth from the GaAs MESFET process. It incorporated a thin-film inverted MSM photodetector to achieve nearly monolithic integration. The final circuit is a tunable high pass active filter in 0.18 m CMOS technology. As part of a NEXT noise canceller architecture, it will provide the means to extend data transmission in FR-4 legacy backplanes into the tens of Gb/s datarate.

Thesis (M.S.)--Naval Postgraduate School, 2004. / Title from title screen (viewed Aug. 13, 2004). "March 2004." Includes bibliographical references (p. 71-73). Also issued in paper format.