الفهرس 
an overwiw of wireless systems and antennasOnly 14 pages are availabe for public view
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Abstract
The thesis introduces new proposals for smart wire and patch antennas in the field of mobile communications. These antennas can be used in many applications with different frequency bands as mobile communications systems (GSM, and PCS), wireless local area networks, and global positioning system (GPS). These antennas have been contributed in local or international conferences.
The first chapter presents an overvIew about the current and proposed wireless communication systems. It also contains an idea about the proper antennas for each system, with brief note about the requirements and challenges that faces the antenna design. The chapter is provided with the frequency bands for each system.
The second chapter presents the method of moments technique, used for studying and analyzing the performance of the proposed antennas in the thesis. The chapter covers the mathematical equations, which describes this technique followed by a wire antenna example to clarify the idea. The chapter introduces the computer software that is used to apply the method of moment technique. It mentions the conditions, which must be respected in entering the under-study antenna configurations.
The third chapter proposes a new wire monopole antenna loaded with a collection of vertical and horizontal wires. This collection is configured at certain positions and dimensions to meet the requirements of the antennas used in the mobile communication system ”GSM”. The antenna has reasonable gain with omnidirectional radiation pattern. The hand-held unit has been represented as a conducting box with suitable dimensions. Two cases of the antenna have been considered; center-mounted above the unit topside, and corner-mounted The Subband Coding (SBe) and Wavelet Transform (WT) are widely used in the area of signal processing and communication as speech and image coding techniques. We review the subband coding, the different structures of filter banks and the design of these filter banks using FIR Quadrature Mirror Filters (QMF). We present the design of fiR QMF and discuss its stability.
The Wavelet Transform (WT) and the computation algorithms of the Discrete Wavelet Transform (DWT) will be reviewed. The relation between the DWT and the subband coding is discussed and we present the conversion algorithms between these two techniques.
Both SBC and DWT deal with the speech as 1 dimension (lD) signal and image as 2 dimension (2D) signal so we review the conventional algorithms used in the speech and image coding. We present a process that can be applied on the image so it gives us the ability to use the same algorithm on both speech and image signals. Finally, we propose a complete system that achieves this method.
This thesis consists of seven chapters organized as follows:
Chapter 1 represents the different coding techniques either in time- or in frequency¬domain. It explains the importance of the digital data compression and its applications. It discusses the speech compression and the requirements of the low bit rate coders. It represents the image compression and its applications. Finally it shows the aim of this thesis.
Chapter 2 makes a survey on the further works in the subband coding using different digital filter bank structures and in the wavelet transform using different computation algorithms. It reviews relation between these two techniques.
Chapter 3 briefly reviews the different structures of QMF banks such as: 2-band, tree¬structure and M-band maximally decimated QMF bank. The design of the latter one is