Objective to provide a study of different fractal antenna with an overview of recent developments. In this report, attention is called to this developing, but already quite large, field of study. Fractal antenna theory uses a modern fractal geometry that is a natural extension of euclidian geometry. In the far field of a herzian dipole the radiated electric field is approximately. Having never encountered a situation where a fractal antenna has been used, i decided to build up a triangle fractal antenna and test it, as i evolve it from a simple bowtie antenna through iterations to become a fractal. More complex, directional antennas consist of arrays of elements, such as dipoles, or use one active and several passive elements, as in the yagi antenna. Technical report pdf available may 2015 with 3,623 reads how we measure reads a read is counted each time someone views a publication summary.
Fractal antennas can take on various shapes and forms. This antenna is recommended when fm receiver has 300. Santanu kumar behera department of electronics and communication engineering national institute of. Design and analysis of fractal antennas for wideband applications a thesis submitted in partial fulfilment of the requirements for the degree of bachelor of technology in electronics and communication engineering by ombeni kanze kennedy roll no. Isbell and raymond duhamel individual componentsdipoles length and spacing of elements of lpa increase logarithmically from 1 end to the other z and r characteristics that are regularly repetitive as a logarithmic function of the excitation frequency multielement. Choosing circuit materials for lowpim pcb antennas. Research article attitude estimation for inservice base.
Design and analysis of fractal antennas for wideband. The length is approximately 7 inches 18cm and the width is about 3. For pcb antennas, low pim is a function of the antenna design but also of the choice. It is the best receiving dipole, because it has the. For example, a quarter wavelength monopole can be transformed into a similarly shorter antenna by the koch. Development of onesided directional thin planar antenna for. Download and print antenna template print out one copy each of part 1 and part 2 of the. Dipole reflector antenna, 88108 mhz, 4 dbd, 250watts, hv.
The fractal antenna not only has a large effective length, but the contours of its shape can generate a capacitance or inductance that can help to match the antenna to the circuit. In the brief study of fractal antennas for this report, i have found. I start with a simple bowtie antenna as shown in figure 4. Fractals a fractal is a rough or fragmented geometric shape that can be subdivided in parts. A fractal antenna is an antenna that uses a fractal, selfsimilar design to maximize the length, or increase the perimeter on inside sections or the outer structure, of material that can receive or transmit electromagnetic signals within a given total surface area or volume. The geometry of how this antenna could be used as a dipole is shown in fig 1. Fractal antenna theory is built, as is the case with conventional antenna theory, on classic electromagnetic theory. By definition, an antenna is a device used to transform an rf signal, traveling on a conductor, into an electromagnetic wave in free space.
A dipole antenna is two pieces of wire, rod, or tubing that are onequarter wavelength long. This antenna has been tested to withstand strong winds for years, but it is not guarantee how strong storms can it withstand. Electromagnetic waves are often referred to as radio waves. We are seeing fractal antenna theory shedding new light on our understanding of classic wideband antennas. Most of the doityourself hobbyists claim that the antenna perform well in receiving the signal but did not mention how good is the antenna reception in. How to make a fractal antenna for hdtv dtv plus more on.
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