Transmission impairments degrade the quality of optical signals, ultimately limiting the achievable transmission distance. Optical 3R regenerators provide an effective means of coping with transmission impairments by restoring the quality of optical signals through reamplification, reshaping, and retiming (3Rs), thereby enabling reliable transmission over long distances. Beyond the 3Rs, however, regenerators must also be able to operate within the practical constraints of the network. The specific network of interest in this thesis is referred to as an agile all-photonic network (AAPN). In AAPNs, traffic consists of optical packets that are routed through the core of the network without undergoing optical-to-electrical conversion for signal processing (e.g., 3R regeneration). As a result, 3R regeneration must be performed all-optically, otherwise known as all-optical 3R regeneration (AO-3R). Although a variety of AO-3R techniques have been demonstrated, none have been specifically designed to operate within the practical constraints of AAPNs. In this thesis, a 10 Gb/s all-optical 3R regeneration (AO-3R) technique is proposed, specifically designed to operate within the practical constraints of AAPNs. The technique performs AO-3R in a novel 2-stage design. In the first stage, all-optical retiming is achieved using a self-pulsating distributed feedback laser (SP-DFBL) for all-optical clock recovery and cross-phase modulation (XPM) in highly nonlinear fiber (HNLF) with offset spectral slicing for the retiming. In the second stage, all-optical reshaping (and reamplification) is achieved using self-phase modulation (SPM) in HNLF with offset spectral slicing. Experimental assessment of the AO-3R system performance yields excellent results. In particular, AO-3R is shown to improve the performance of input signals degraded by transmission impairments, such as amplified spontaneous emission (ASE) noise, while providing low sensitivity to input signal properties, such as the state-of-polarization. Furthermore, AO-3R is shown to successfully achieve its ultimate goal for AAPNs – the regeneration of optical packets. / Thesis (Ph.D, Electrical & Computer Engineering) -- Queen's University, 2007-08-09 16:31:25.462

Cavity ring-down spectroscopy (CRDS) is an absorption spectroscopic technique. In CRDS the concentration of an analyte is determined by measuring the reduction in finesse of an optical cavity made from two highly reflective (R>99.9%) mirrors once a sample is introduced. Optical loss is traditionally determined from the exponential intensity decay of a short laser pulse that was injected into the cavity. This decay is the longest for an empty, high finesse cavity and is reduced when the sample absorbs or scatters light. In this project, the optical cavity is made from fiber optic waveguides and the light source is a continuous wave (cw) diode laser. It is used to detect analytes such as acetylene, ammonia and other amines through their overtone absorption in the telecom region at 1500 nm. The experiment is done by increasing the ratio of desired loss (extinction caused by the sample), to undesirable loss (from the waveguide or solvents) through amplification of the ringdown signal using an erbium doped fiber amplifier (EDFA). The EDFA is inserted into a fiber-optic loop and its gain is increased above the lasing threshold. The gain of the, now lasing, fiber loop is "clamped" to a high and constant value, thereby removing unwanted gain fluctuations, and all losses in the loop are compensated for. If one now inserts a laser light pulse at the lasing wavelength of the loop it would circulate through the loop indefinitely, whereas a light pulse at a wavelength that is being absorbed by an analyte would experience a decrease with time at a rate that depends only on the magnitude of the sample absorption. By enclosing the sample gap with a gas cell both acetylene and ammonia have been detected down to ~25 ppm and ~5.9 Torr respectively. Subsequently, a 1% solution of aminotoluene was detected in an interrogation volume of 5.65 pL by having inserted a fiber with a hole drilled in it as the sample gap. At present, the drilled fiber has been replaced with photonic crystal fiber such that small volumes of gases may be detected with a longer effective path length. / Thesis (Master, Chemistry) -- Queen's University, 2011-09-23 18:27:47.65

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No description available.

Thesis (MAppSc)--University of South Australia, 1994

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1990. / Vita. Abstract. Includes bibliographical references (leaves 72-75). Also available via the Internet.

Thesis (Ph. D.)--School of Physics, Faculty of Science, University of Sydney, 2004. (In conjunction with: Université de Droit, d'Économie et des Sciences d'Aix-Marseille (Aix Marseille III)). / Bibliography: leaves 196-204.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1991. / Vita. Abstract. Includes bibliographical references (leaves 103-105). Also available via the Internet.

Thesis (Ph. D.)--University of Sydney, 2004. / Title from title screen (viewed 14 May 2008). Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the School of Physics, Faculty of Science in conjunction with: Université de Droit, d'Économie et des Sciences d'Aix-Marseille (Aix Marseille III). Includes bibliographical references. Also available in print form.

Thesis (M.S.)--Rochester Institute of Technology, 1992. / Typescript. Includes bibliographical references.