دراسة تاثير الترابط والقدرة الضائعة في الموجهات المترابطة على كفاءة المجمع - الموزع البصري باستعمال طريقة الفروقات المحددة == Study The Effect of Coupling and Crosstalk in Directional Couplers on The Performance of Multi / Demultiplexers Using Finite Differences Method
Author name:
منصور حنظل منصور زغير
Supervisor name:
صباح مهدي محمد امين
General topic:
Physics
Specific topic:
Physics
Degree:
Master
University:
University Of Basrah - College Of Science
Language:
Arabic
University location:
Basrah
First pages:
26T1692 - p.pdf
Abstract:
Directional couplers can be used to make important planar optical integrated circuits for optical communications, such as Mach - zehnder interferometers and wavelength division multiplexers. Wavelength division multi/demultiplexing of optical signals is an efficient means to increase the information density per fiber.Both the coupled mode theory and the FD numerical method are used in this study to analyze multiwaveguide DCs.In this thesis, we present an analytical expression for crosstalk of MWGDC based on relationship between the normal modes and local modes, where these modes are obtained numerically using FD mothed.Also, the mode field profile and their evolution along the structure are presented through the analytical expression and calculated numerically using FD method. With the help of this analytical expression, the input power can be controlled to be enter from a chosen hannel. This enable us to calculate the crosstalk that corresponds to a certain input channel.The transmission characteristics of a four channel multiplexer based on three MZI can be described in terms of the propagation matrices. In this study, the coupling coefficient of DC and the phase shift of MZI are treated to be wavelength dependent parameters. Crosstalk introduced by such process are also calculated.The transmission characteristics of three arm MZI as a DWDM is investigated theoretically by deriving the propagation matrix of 3WGDC using coupled mode theory. Thus, two parameters are introduced, and , as a designing controlling parameters for DWDM devices. By adjusting these parameters a DW DM devices can be presented.
