الفهرس 
Optical Fiber Sensor- A Historical ReviewOnly 14 pages are availabe for public view
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Abstract
This thesis concerns with modeling Fiber Bragg Grating (FBG) for temperature measurement for the safe operation of Material Testing Reactors (MTR). Fiber optic technology covers many applications in nuclear reactors such as data communication and sensing of different safety parameters. FBG is an attractive type of sensing systems for its advantages. The simulation of Bragg grating occurs by OptiSystem7 simulator, through the design of a communication system model for the maximum reflectivity. Also, characterization of fiber Bragg grating as a temperature sensor for nuclear applications using Opti-grating software7 is presented. Apodization techniques for signal processing are used to provide accurate measurements which required in nuclear applications.
The effect of grating length for different Apodization functions on the overall performance of an optical communication system has been studied. The system layout was performed by utilizing Optisystem software7, where 5 Gb/s non return to zero signal was attacked into single mode fiber and fiber Bragg grating. The values of system performance parameters like maximum quality factor and minimum bit error rate have been analyzed and calculated by using eye diagram. A specific study to characterize the fiber Bragg grating (FBG) to arrive at the optimal grating length dimensions for maximum Q-Factor and minimum BER for wide applications in nuclear reactors. Also, Bragg wavelength shift is examined under different gamma irradiation doses for both silica and sapphire FBG. Also, this work included the important feature for temperature dependent Vertical Cavity Surface Emitting Laser (VCSEL) characteristics in the FBG simulation.
The technologies of Wavelength Division Multiplexing (WDM) have been theoretically studied and analyzed for multiplexing fiber Bragg gratings (FBGs) in a single optical fiber. This method allows a single fiber to carry many of identical FBGs, making this sensor more appropriate in the nuclear reactors. The analysis demonstrates that the multiplexing capacity can be incredibly enhance small data rates and high channel spacing. The interference effect among FBGs multi-reflections channels must be taken into account. Simulation of WDM based FBG for a channel spacing of 0.1, 0.3, 0.5, 0.8, 1 nm Gaussian apodized FBGs at data rates of 2.5, 10, 40,100,160, 250 Gb/s respectively for nuclear applications. All simulations were performed in Optisystem software7 by Optiwave.