Thesis

Simulation of different OFDM system synchronization using FPGA.

Abstract:This work focuses on the synchronization in orthogonal frequency division multiplexing (OFDM) systems, which arises to be one of the most critical operations. The OFDM system is explained in details and the synchronization problems occurring in this system are classified with the techniques used to overcome these problems. These techniques are 1-“maximum likelihood estimation” for timing and frequency offset, 2-the “Schmidl and Cox” timing and frequency offset estimation, and 3-synchronization of IEEE 802.11a standard signal or wireless LANs (WLAN).

إنجليزية

Analysis of adaptive downlink multiuser mimo wireless communication system.

Abstract:Multiple-input multiple-output (MIMO) wireless communication systems have received significant attention due to their enormous channel capacity potential in rich scattering environment. Such systems need to consider multiuser transmission / reception in their design. This thesis investigates theoretically the ergodic capacity of multiuser MIMO systems operating with adaptive techniques to enhance their performance.

إنجليزية

Design of switched-mode power supply for TEA CO2 laser.

Abstract:This work is to design and simulate a switched mode power supply (SMPS) with the required pulsating circuits, to be used in pumping a TEA CO2 laser. The main parts of the switched mode power supply included: input rectifier, input smoothing filter, push-pull converter (chopping circuit), high voltage power transformer, output rectifier, and output smoothing filter. The control circuit for controlling the chopper circuit was the PWM scheme control circuit and the main switching device in the power converter circuit was the bipolar power transistor with high voltage rating.

إنجليزية

Design and simulation of MIMO-OFDM receiver employing turbo equalization.

Abstract:Orthogonal frequency division multiplexing (OFDM) is a promising technique for high data rate wireless communications because it can combat intersymbol interference (ISI) caused by the dispersive fading channel. This is achieved by inserting a guard interval, whose length is at least equal to the maximum channel delay, which reduces the transmission efficiency. Applying multiple-input multiple-output (MIMO) scheme, by adopting multiple transmitting and receiving antennas, can enhance the transmission efficiency and link reliability.

إنجليزية

Simulation of GSM and GSM/EDGE mobile communications System.

Abstract:The introduction of global system for mobile communication (GSM) air interface has undoubtedly created a new area in telecommunications. In view of its extensive use in real world applications, it is highly desirable to further investigate the performance of the GSM system under different operating conditions and environments. Furthermore, there is increasing interest in using high-level modulation to provide enhanced data rate for GSM evolution (EDGE). This thesis investigates the performance of both GSM and GSM/EDGE systems operating in Raleigh fading channel.

إنجليزية

Analysis and modeling of thermal effects on the parabolic reflector antenna performance.

Abstract: Large antennas, such as required for radio astronomy or interplanetary probes, or ground stations of satellites, are engineering structures subject to gravity, wind, and thermal strains. The conditions especially the temperature gradient can cause undesired shape deformation, twists, and strain concentration in the structure, which can adversely affect the performance of antenna systems for both pointing and accuracy. In this thesis the thermal effects on the electrical characteristics of the reflector parabolic antenna are studied.

إنجليزية

Computer based configuration for cisco routers.

Abstract: Routers are intelligent devices that make connection between different networks possible. In addition, routers can perform several functions, including filtration and selection of the best path of packets movement. Routers must be configured efficiently in order to perform the above functions. In literature, two approaches have been distinguished for the configuration, namely; text mode and graphical mode approach. The present work is analyzing these two approaches and defines precisely their advantages and limitations.

إنجليزية

Simulation of coded multiuser OFDM downlink.

Abstract: The orthogonal frequency division multiple access (OFDMA) scheme adopts orthogonal frequency division multiplexing (OFDM) subcarriers, which are particularly suited for transmition over broadband frequency selection channels, to support multiusers. The scheme considered usually assigns a subset of subcarriers to each user and adopted adaptive techniques for the allocation of available resources/subcarriers according to the channel state information (CSI) estimated at the transmitter using a reverse link.

إنجليزية

Simulation of adaptive coded modulation for OFDM communication Systems.

Abstract: In this thesis, an adaptive modulation and coding (AMC) scheme is applied to OFDM wireless communication systems. This scheme offers an alternative wireless link adaptation approach that promises to raise the overall system capacity. The AMC provides the flexibility to match the modulationcoding scheme to the average channel conditions. With AMC, the power of the transmitted signal is held constant over a frame interval while both the modulation and coding formats are changed to match the received signal quality.

إنجليزية