الفهرس 
Thesis OrganizationOnly 14 pages are availabe for public view
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Abstract
The objective of this work aims to improve the performance of chromatic dispersion compensation in single-mode optical fibers (SMF). To achieve this, proposed two main models. The first model is a designed fiber-based model and the other is a standard single mode fiber (SSMF)-based model. Designed fiber-based model includes two models, soliton model and maximum time division multiplexing (MTDM) model. It consists of a 4 Levels of Cascaded Identical Apodized Uniform Fiber Bragg Gratings (AUFBGs) and soliton/MTDM modulator. Matlab is used in simulation of the designed fiber-based model. The model is evaluated in terms of the transmission bit rate (Br). It starts with determining the best operating parameters of a single mode silica doped optical fiber for dispersion compensation. Then, the cascaded AUFBG stages reshape the input optical signal. By using the most useful apodization functions, we generated six schemes of this model. For each scheme, Calculate the transmission bit rate of the output signal. Then, compared between calculated transmission bit rates of each scheme to find the best scheme of the proposed model. The two models have the same response to the dependent and independent operating parameters. The soliton model simulation results show that, the raised cosine apodized identical 4-stages cascaded UFBGs is the best scheme. It has a maximum Br of 1.9932 Gbps. The MTDM model showed better performance than soliton model. The best MTDM scheme is the raised cosine apodized identical 4-stages cascaded UFBGs with MTDM at a maximum Br of 7.6973 Gbps.
The two SSMF-based models are proposed to optimize the chromatic dispersion compensation in SSMF. The first model is based on applying a duobinary (DB) modulation format to four identical AUFBG stages that are cascaded. Test different apodization functions to determine which one gives the best performance. Also,
Another SSMF-based model consists of four stages of identical linear chirped fiber Bragg gratings (CFBG) cascaded in a compensated interconnection scheme. It is based on the DPSK (Differential Phase Shift Keying) modulation format. To evaluate the performance of the proposed model, a comparative study is conducted using offset quadrature phase shift keying (OQPSK) modulation technique. This comparative study includes four cases with and without CFBG. To evaluate system performance, a 10 Gbps wavelength division multiplexed (WDM) link is simulated over a distance of 70 km under typical operating parameters. The proposed model shows the best performance when using CFBG compared to other cases. The results obtained are a Q-factor of 7.22 and a BER of 2.59 x 10 -13.
Best proposed model of the two main models is the SSMF-based model under DPSK modulation using a 4-satges identical cascaded tanh-apodized chirped FBG (CFBGs) in post-compensation scheme. This model achieves a percentage of enhancement, in terms of BER, in the system performance over the related work at least 97%.