The process of configuring the meandered ring antenna [ 19 ]. Thus, the total length of meandered ring equals 5. The length of meandered ring increases by a factor of 1. Of course, the increase in length of the four arms leads to increase in the length of the surface current paths and thus generates new resonant frequencies which collected together to give a wide impedance bandwidth, and this is clear in Figure 17 the solid curve where the operating band increased when the ring becomes meandered at the second iteration.
The simulated reflection coefficient for the 0th iteration, first iteration, and the second iteration [ 19 ]. Figure 17 depicts the real black curves and imaginary blue curves parts of the impedance values for the three antennas. Thereafter, the values of real-part impedance for the second iteration are closer to the input impedance of excitation port 50 ohms red line , especially in the frequency range of 5.
In the frequency band of 4. This property provides stable matching factor that leads to stable gain and efficiency in the operating band.
The impedance values of the three iterations [ 19 ]. Table 3 illustrates some important radiation properties for each iteration, such as impedance bandwidth, efficiency, gain, and ARBW. It is clear that most of the required specifications that can be achieved at the second iteration are due to improving the values of radiation properties during the progress of antenna configuration, especially the impedance bandwidth, efficiency, gain, and an ARBW as shown in Table 3.
The maximum distribution currents at 5 GHz for the 0th iteration are mainly concentrated close to the feeding point on the patch and ground plates, as shown in Figure In the first iteration, the currents are distributed in the additional area, especially on the square ring, which leads to the generation of new resonant frequency. The operating band is expanded compared with that at 0th iteration.
The distribution of the surface current on ground plate is the same in all iterations because there is no change in surface current path at the ground plate during the progress of antenna configuration compared with the radiator plane. The surface current at 5 GHz for all iterations [ 19 ]. Figure 19 second iteration shows that the surface current has two paths. The first path begins from the feeding point F and then passes through the right arm to point A, which has a total length equal to 1.
The total length of the other path, which is almost perpendicular to the first and begins from feeding point F and then passes through the bottom arm to point B, is equal to 1.
Thus, two equal components of surface current normal to each other provide circular polarization radiation at 5 GHz. The length of the first surface current path from feeding point F to point A is 16 mm, which is almost equal to the length of the second surface current path from the feeding point to point B. Figure 21 depicts the left and right polarizing radiation in E-plane at 5 and 5. This study matches the surface current distribution, which indicates that a circular polarization radiation at 5 GHz is generated by dual orthogonal components of electrical field created by the surface currents that flow along the perpendicular arms of the meandered ring at the feed point, as shown in Figure Simulated left black curves and right red curves polarization in E-plane at 5 and 5.
Figure 22 represents the photographs of the all iteration prototypes; it is clear that the size of the proposed antenna is compact that can be used for portable communication devices. The prototypes of all fractal antenna iterations [ 19 ]. The measured impedance bandwidth for the proposed antenna compresses to the frequency band of 4. That takes place due to impurities of some of the materials that are used in prototypes and due to the soldering.
Measured dashed and simulated solid S 1 , 1 for the proposed antenna [ 19 ]. Figure 24 shows a distinguishing agreement between simulated solid and measured dashed patterns. Radiation patterns in the H-plane black curves for the proposed antenna are almost omnidirectional at 5 and 5. Figure 24b shows that the radiation pattern at 5. Simulated solid and measured dashed radiation pattern. Figure 25 depicts the measured values of the gain, efficiency, and an axial ratio. At frequency bands of 5—6 GHz, gain values are almost constant 2.
Measured gain, efficiency, and AR for the antenna [ 19 ]. Although the meandered ring fractal antenna has impedance bandwidth that covers only the upper band required for Wi-Fi, WiMAX, and ISM applications, it has stable radiation properties especially the gain and the efficiency. Fractal geometry is another type of micro strip antenna used in designing antennas. Two fractal antennas, namely, dual-input fractal antenna and meandered ring antenna, were investigated.
All antennas are fabricated on commercial and cheap FR-4 substrate. The proposed fractal antennas are CP radiated by generating orthogonal components of electrical field. The measured operating bands for the first input of the fractal antenna are 2. The prototype of the dual-input fractal antenna displays an ARBW of 2. The values of the measured gain vary between 0 dBi at 2. Thus, the meandered ring monopole antenna is suitable for the requirements of portable communication devices.
Table 4 shows that the previous fractal antennas have circular polarization radiation, such as those reported in [ 3 ], which is the Giuseppe Peano fractal antenna that covered the frequency band of 1. The antenna has an ARBW of 0. This meandered line antenna only covered the first band. The size of this antenna is very large and its efficiency has not been mentioned in the report. Modified Koch curve is used in designing the antenna based on Fibonacci sequence reported by [ 23 ].
The antenna does not cover the lower band 2. Therefore, the two proposed fractal antennas in the current study dual fractal and meandered ring antennas have specific characteristics better than the previous related antennas in Table 4. The meandered ring fractal only covers the upper band 5—6 GHz. Secondly, acceptable and greater values of gain for both antennas than the specified gain for fractal antennas in Table 4 compared with their compact size.
Despite the small size of the proposed antennas compared with many of the previous fractal antennas in Table 4 , the manufactured antennas in the present study are characterized by superior and stable efficiency, thereby making them suitable for Wi-Fi and WiMAX applications. Place the fractal design you chose under the Plexiglas, and place the solder metal close to the iron but not touching it directly.
Follow the design with the solder and soldering iron in hand. Note: Amelia and I attempted to solder on the paper, resulting in the burnt appearance. Before settling on Plexiglas, we attempted to solder on wood, duck tape, and manila folder. The solder was not able to stick to these surfaces. Allow the solder fractal antenna to cool for at least 30 minutes without coming into contact with any other objects.
This is to preserve the shape and self similarity of the fractal. Next, allow the solder iron to cool for an hour before putting it away. This is for safety reasons concerning the high temperatures involved. In order to build this fractal, you will need aluminum foil, manila folder, graph paper, a pencil, and the stapler. Next, fold the strips of wire along the fractal design of your choice on paper. If you chose to sketch it on graph paper as we did, you would construct along a piece of graph paper placed on top of manila folder.
In order to connect the individual strips of foil, staple at their junctions. This will not interfere with reception as the staples act as a conductor. To build this antenna you will need the roll of insulated wire, nails, wood, and a pair of scissors.
Screw the nails into the wood, and situate your fractal around them in a fashion where the shape of the fractal is present. In order to connect your fractal antenna to a TV, you need to have wire that is exposed at the end running from the antenna jack to your fractal antenna.
As far as attaching the wires to the aluminum foil fractal we simply maneuvered the wires underneath the foil so they were between the foil and the paper. As far as the Solder Fractal, we used scotch tape to hold the wires in place, and we held the wires against the fractal with our hands, allowing us to experiment with the angle positioning of the fractal.
We did the same thing for the Insulated Wire Fractal. As part of our testing, we positioned the wires at different points on the fractals Solder and Aluminum Fractal , and were met with largely the same results. In regards to even the amount of wires used, at times the reception was better when only one wire was placed on the fractal at one time instead of two.
We believe this may have been the result of self interference on the part of the wires and the fractals. Make sure that the exposed end of wire is securely attached to your antenna tape will work , and turn on your television! It took approximately 6 hours to test the solder and the antenna for the solder fractal, 3 hours to test the Aluminum fractal, and 1 and a half hours to test the wire fractal.
It took 1 hour to construct the solder fractal, a half hour to construct the aluminum fractal, and 45 minutes to construct the wire fractal. It took 3 hours to brainstorm on the solder fractal, 1 and a half on the aluminum fractal, and 45 minutes on the wire fractal.
If we were to do this project again, we would make thealuminum wire strips thicker because it allows for better reception. To do this, we would rip off 12 inch pieces at a time and then fold them. This would be minimally difficult.
We would also go to a place outside of school to further test coverage. Being inside the school allows for a degree of interference by walls and buildings. We could test this by mounting the fractal antenna on the window of a house for instance. Participated in the Gadget Hacking and Accessories Contest. You might try attaching the wire to the antenna at different locations and not always the same distance away from each other or an equal distance along each path.
You might also include drawings as to where you attached the wires, either I missed them or they weren't included. The old bow tie UHF antenna is a very basic fractal in some ways I guess. A full-wave-loop antenna is very similar in look to your snowflake fractal. The way it is normally attached to the radio or TV is by breaking the loop at some point and attaching both wires from the radio or TV to those two end points, one end point and one wire.
In this case you may have an antenna array and not a simple loop antenna. Also, with your feed line attached to opposite ends of the snowflake you have inadvertently used part of your feed line as part of the antenna, which changes things considerably.
A feed line separated and stretched out is a form of dipole antenna. The most basic of all antennas is the half wave dipole, meaning that the length of the dipole antenna is one half the wavelength of the radio frequency you want to receive or transmit.
Thus, the full-wave-loop is an antenna whose length is equal to one wavelength of the frequency of interest. With TV frequencies one can never design a single element antenna capable of receiving all the wanted frequencies equally.
Your fractal antenna might be able to better manage this wide frequency range requirement. As for the triangle antenna I'd like to know how you attached the wires to it. I may have to keep this around and try some tests on it as well. If one were to take a full wave loop already attached to the feed line and un-loop it, it could be made to look like half of your snowflake fractal antenna so, I guess in a sense, you have two stretched out and somewhat bowed "loop" antennas attached to the feed line, that's a form of antenna array, two or more antennas attached in some way.
Here Sierpinski fractal antenna has been proposed and presented. Traditionally each antenna operates at a single or dual frequency bands where different antenna is needed for different applications. Low cost of fabrication and low profile features of microstrip antenna attract many researchers to investigate the performance of this antenna in various ways.
Effect of antenna iterations stresses upon reducing metal usage thereby saving cost and also achieved good reflection coefficient. Recent studies on fractal antennas show that these structures have their own specific characteristic that improve certain properties when talking about low profile antennas.
Werner and P. Douglas H. Werner, Randy L. Haup and Pingjuan L. Werner and R. In fact, I am doing my very best work right now. The Symphony-SP represents a material improvement to existing solutions, delivering wideband coverage in a highly reduced size and weight.
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