Electronic and Communication - Engineering

Abstract: Smart antennas systems (SAS’s) have gained a lot of interest due to the explosive growth in demand for mobile communications in the last few years to overcome practical challenges in providing the service. The main benefit of the SAS technology lies in its ability to exploit the spatial domain, on top of the temporal and frequency domains, to improve the transceiver performance. Uniform Circular Arrays (UCA’s) are of interest because of their natural ability to provide a full azimuth (i.e.

Abstract: Optical code division multiple access (OCDMA) is used recently as access method in optical fiber networks without the need for traffic management or system synchronization. It takes advantage of the sporadic use of channels by allowing many users to be simultaneously connected to the network. Among OCDMA systems, frequency-encoded optical code division multiple access (FE-OCDMA) deserves close attention because it solves many obstacles which appear in conventional OCDMA systems such as multiple access interference (MAI). In this work, an incoherent FE-OCDMA systems are modeled.

Abstract: In this thesis, the various aspects related to controlling induction motors are investigated. Different control strategies are explored. The direct torque control (DTC) strategy is studied in details and its relation to space vector modulation (SVM) is emphasized. A SVM-based DTC strategy is suggested and a controller design which is based on the strategy is presented. A Simulink model representing the controller is developed and verified through this of MATLAB work.