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OTDM to WDM conversion
Kupčiha, Lukáš ; Křepelka, Václav (referee) ; Filka, Miloslav (advisor)
The aim of this thesis was introducing the options of conversion between OTDM and WDM technologies. Since this issue is rather extensive, first of all the principle of optical transmission system is described. One chapter presents the effects influencing the optical transmissions. Material absorption, linear and nonlinear scattering and bending losses are mentioned in terms of fiber losses, followed by description of waveguide, chromatic and polarization-mode dispersion of optical fibers. Last part of the chapter presents nonlinear effects, including self-phase modulation, cross-phase modulation and four-wave mixing. The practical part of the thesis deals with multichannel systems. The principles of frequency, space a hybrid multiplexing are explained. Multichannel systems with optical time domain multiplexing and waveguide multiplexing are described in detail and compared. The elements of the transmission chain of multiplex, such as different types of lasers, detectors, modulators, optical amplifiers, splitters, couplers, MUX and DEMUX are discussed. The next part of the thesis was aimed at suggesting the model of mutual conversion between OTDM and WDM systems. First of all, the previously performed experiments concerning the conversion between OTDM and WTM were evaluated. Then the model of OTDM/WDM/OTDM conversion was designed, with explanation of its parts and their function. The general recommendations for practical implementation were are also included. Due to the limited amount of time reserved for access to the simulation program Optsim, the simulations were performed only for certain parts of the proposed conversion model. At the end of the thesis, the proposed model is evaluated.
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Nonlinear phenomena in optical fibers
Burian, Radek ; Horváth, Tomáš (referee) ; Münster, Petr (advisor)
The subject of this thesis is to describe nonlinear phenomena in the optic fiber. The theoretical part describes a principle of transmission in optical fibers. Optics modules, fibers and their parameters are described marginally. Except nonlinear phenomena, there is also described linear phenomena such as attenuation, dispersion, scattering. In terms of nonlinear phenomena there is described second order phenomena such as Second harmonic generation (SHG), Sum and difference harmonic generation (SFG and DFG) and third order phenomena, such as Kerr effect, Third harmonic generation (THG), Four-wave mixing (FWM) and Cross phase modulation (XPM). There are also described nonlinear scattering, such as Raman´s and Brillouin´s scattering. The Four-wave mixing is simulated in the first half of the practical part. Four-wave mixing occurs in DWMD systems, where can invoke cross-talks between channels. In the second half of the practical part is measured this nonlinear phenomenon. The aim of the measurement is to understand the behaviour of the FWM and find the way how to eliminate its power. The Four-wave mixing measurement is based on the simulation. Second measurement is designed for Brillouin scattering. The conclusion from simulated and laboratory part from both measurements are compared with theoretical knowledge.
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Linear and nonlinear phenomena in optical access networks
Valášek, Martin ; Münster, Petr (referee) ; Šifta, Radim (advisor)
The aim of this thesis is an explanation of the problem linear and nonlinear phenomena in optical access networks. In the first chapter refers to a description of the optical fiber, description of the optical environment and the main part is theoretical and mathematical description of phenomena that operate in optical fibers. It is therefore a specific attenuation, dispersion, phenomena of second and third-order, nonlinear light scattering and solitons. Then there is the dismantling brief overview of the distribution of access networks and their description. The second part deals with specific simulation of these phenomena in the simulation program OptSim 5.2. All connections will be implemented in the block diagram Sample-Mode, in which using appropriate units and setting the right parameters, we will try to confirm the theoretical assumptions of the first part.
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The mutual conversion of the OTDM and WDM systems
Végh, Zoltán ; Šifta, Radim (referee) ; Münster, Petr (advisor)
The aim of the diploma thesis is to analyze the WDM and OTDM optical telecommunication networks and the possibility of conversion between these two multiplexing methods. In the first chapter were mentioned the basics of optical communication. The next chapter describes the optical fiber. Specifically, their types, linear and nonlinear optical characteristics whitch are limiting transmission e.g. attenuation, dispersion, refraction, FWM, SPM and XPM. Followed by a general description of the multiplexing systems used in optics and individual elements used in various multiplexing systems. The last chapter was devoted to the design of the OTDM - WDM conversion model.
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Non-linear character of optical environment
Žáček, Martin ; Míča, Ivan (referee) ; Přinosil, Jiří (advisor)
This paper describes theoretical and application options of nonlinear effects in optical medium. Optical medium means fiber optics, because the fiber is the most employed optical medium at these days. Basic statements of this work are theoretical information with mathematical and physical expressions. These expressions defines nonlinear medium and effects which are founded here. These effects are split to second and third orders. Nonlinear effects of second orders are Second-harmonic Generation, Three-wave Mixing process. Nonlinear effects third orders are Third-harmonic Generation, Self-phase Modulation, Cross-phase Modulation, Four-wave Mixing and Degenerative Four-wave Mixing process. These effects are extended by scattering effects – Brillouin’s and Raman‘s Scattering. The next point discuss about optical communication system DWDM. DWDM uses dense wavelength multiplexing. Nonlinear effects have a few negative influences on these systems. There are requests for high bandwidth and communication speed. FWM and XPM limit these requests. They can invoke cross-talks. We support theoretical information with application examples and simulations at the end of this work. We use OptSim v.4.0 program. We are simulate FWM and XPM effect in depend on chromatical dispersion and power.
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Nonlinear phenomena in optical fibers
Burian, Radek ; Horváth, Tomáš (referee) ; Münster, Petr (advisor)
The subject of this thesis is to describe nonlinear phenomena in the optic fiber. The theoretical part describes a principle of transmission in optical fibers. Optics modules, fibers and their parameters are described marginally. Except nonlinear phenomena, there is also described linear phenomena such as attenuation, dispersion, scattering. In terms of nonlinear phenomena there is described second order phenomena such as Second harmonic generation (SHG), Sum and difference harmonic generation (SFG and DFG) and third order phenomena, such as Kerr effect, Third harmonic generation (THG), Four-wave mixing (FWM) and Cross phase modulation (XPM). There are also described nonlinear scattering, such as Raman´s and Brillouin´s scattering. The Four-wave mixing is simulated in the first half of the practical part. Four-wave mixing occurs in DWMD systems, where can invoke cross-talks between channels. In the second half of the practical part is measured this nonlinear phenomenon. The aim of the measurement is to understand the behaviour of the FWM and find the way how to eliminate its power. The Four-wave mixing measurement is based on the simulation. Second measurement is designed for Brillouin scattering. The conclusion from simulated and laboratory part from both measurements are compared with theoretical knowledge.
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Linear and nonlinear phenomena in optical access networks
Valášek, Martin ; Münster, Petr (referee) ; Šifta, Radim (advisor)
The aim of this thesis is an explanation of the problem linear and nonlinear phenomena in optical access networks. In the first chapter refers to a description of the optical fiber, description of the optical environment and the main part is theoretical and mathematical description of phenomena that operate in optical fibers. It is therefore a specific attenuation, dispersion, phenomena of second and third-order, nonlinear light scattering and solitons. Then there is the dismantling brief overview of the distribution of access networks and their description. The second part deals with specific simulation of these phenomena in the simulation program OptSim 5.2. All connections will be implemented in the block diagram Sample-Mode, in which using appropriate units and setting the right parameters, we will try to confirm the theoretical assumptions of the first part.
|
|
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The mutual conversion of the OTDM and WDM systems
Végh, Zoltán ; Šifta, Radim (referee) ; Münster, Petr (advisor)
The aim of the diploma thesis is to analyze the WDM and OTDM optical telecommunication networks and the possibility of conversion between these two multiplexing methods. In the first chapter were mentioned the basics of optical communication. The next chapter describes the optical fiber. Specifically, their types, linear and nonlinear optical characteristics whitch are limiting transmission e.g. attenuation, dispersion, refraction, FWM, SPM and XPM. Followed by a general description of the multiplexing systems used in optics and individual elements used in various multiplexing systems. The last chapter was devoted to the design of the OTDM - WDM conversion model.
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|
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OTDM to WDM conversion
Kupčiha, Lukáš ; Křepelka, Václav (referee) ; Filka, Miloslav (advisor)
The aim of this thesis was introducing the options of conversion between OTDM and WDM technologies. Since this issue is rather extensive, first of all the principle of optical transmission system is described. One chapter presents the effects influencing the optical transmissions. Material absorption, linear and nonlinear scattering and bending losses are mentioned in terms of fiber losses, followed by description of waveguide, chromatic and polarization-mode dispersion of optical fibers. Last part of the chapter presents nonlinear effects, including self-phase modulation, cross-phase modulation and four-wave mixing. The practical part of the thesis deals with multichannel systems. The principles of frequency, space a hybrid multiplexing are explained. Multichannel systems with optical time domain multiplexing and waveguide multiplexing are described in detail and compared. The elements of the transmission chain of multiplex, such as different types of lasers, detectors, modulators, optical amplifiers, splitters, couplers, MUX and DEMUX are discussed. The next part of the thesis was aimed at suggesting the model of mutual conversion between OTDM and WDM systems. First of all, the previously performed experiments concerning the conversion between OTDM and WTM were evaluated. Then the model of OTDM/WDM/OTDM conversion was designed, with explanation of its parts and their function. The general recommendations for practical implementation were are also included. Due to the limited amount of time reserved for access to the simulation program Optsim, the simulations were performed only for certain parts of the proposed conversion model. At the end of the thesis, the proposed model is evaluated.
|
|
|
Non-linear character of optical environment
Žáček, Martin ; Míča, Ivan (referee) ; Přinosil, Jiří (advisor)
This paper describes theoretical and application options of nonlinear effects in optical medium. Optical medium means fiber optics, because the fiber is the most employed optical medium at these days. Basic statements of this work are theoretical information with mathematical and physical expressions. These expressions defines nonlinear medium and effects which are founded here. These effects are split to second and third orders. Nonlinear effects of second orders are Second-harmonic Generation, Three-wave Mixing process. Nonlinear effects third orders are Third-harmonic Generation, Self-phase Modulation, Cross-phase Modulation, Four-wave Mixing and Degenerative Four-wave Mixing process. These effects are extended by scattering effects – Brillouin’s and Raman‘s Scattering. The next point discuss about optical communication system DWDM. DWDM uses dense wavelength multiplexing. Nonlinear effects have a few negative influences on these systems. There are requests for high bandwidth and communication speed. FWM and XPM limit these requests. They can invoke cross-talks. We support theoretical information with application examples and simulations at the end of this work. We use OptSim v.4.0 program. We are simulate FWM and XPM effect in depend on chromatical dispersion and power.
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