الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
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Abstract
In the last few years the importance Log-periodic broad¬band antennas has grol4ll steadily, especially since the wg¬Per1odioD1polArray and its various modifications have been very successful.
In the present thesis, divided into two main parts, an ex¬tensive study is given about the Log- periodic-Dipole structure.
Part I, subdivided into three chapters, comprises first a note about frequency independent antennas in general. It then treats in parti<Jllar the Log-P eriodie-Dipole-Antenna (or Array),
I -- ..
L PDA: The def’in1tlons relating to\ it, its theory, its method
of feeding, its design procedure and a survey of the work carried out by previous investigators in that field. The summarized pap¬ers deal essentially with the solution of voltage distribution along the line. Transients on the L PDA and features about arrays of’ such radiators are also considered. The optimization of the
L PDA, being a field of wide interest, is treated in chapter I. Some modified versions of the L PDA are treated in details in chapter II, sinoe they are becoming now of great importance.
Part 11, deals with our theoretical and experimental inves¬tigations. The problem of voltage distribution along the Log- Periodio-D1~le-Array with small taper and slowly varying spacings is solved using two methods of analysis, and is given in chapter IV. Both are based on the theory of none””’tlniform transmission lines. A transformation from log-periodic to periodic geometryTo obtain a solution of the log-periodic problem in terms ot its periodic oounterpart is also given in the same chapter . detailed experimental work is given in chapter V of the thesis. It comprises the determination of the field patterns and input impedanoes of some L PM structures especially constructed for the present work, throughout their operating frequency range.
Part II of the thesis includes also a conclusion in chapter VI , and appendices in chapter VII.where proors of some equations appearing throughout the thesis are reported •