Fractal Tree Antenna Research Articles

Design and Simulation of Two Elements Fractal Tree Antenna Arrays

Fractal reception apparatuses have been appeared to exhibit monotonous multi-band or log-intermittent conduct that has been ascribed to the self-comparable scale factor of the recieving wire's geometry. This geometry, which has been utilized to display complex articles found in nature, for example, mists and coastlines, has space filling properties that can be used to scale down reception apparatuses. These exceptional properties of fractals have been abused to build up another class of recieving wire component plans to have a few profoundly attractive properties, including multiband execution, low side flap levels, and its capacity to create quick shaft framing calculations dependent on the recursive idea of fractals. There are a few focal points of these fractal gadgets including decrease of full frequencies, littler size and broadband width. In this paper, another structure of fractal tree recieving wire Arrays dependent on ternary fractal tree geometry for meet the addition or radiation design prerequisites is proposed.Farctal tree radio wire exhibits are plan with two for gain improvement and radiation pattern.Fractal tree reception apparatus clusters upgrade the increase upto 10 dB.

Significant performance enhancement in continuous wave terahertz photomixers based on fractal structures

A photoconductive fractal antenna significantly improves the performance of photomixing-based continuous wave (CW) terahertz (THz) systems. An analysis has been carried out for the generation of CW-THz radiation by photomixer photoconductive antenna technique. To increase the active area for generation and hence the THz radiation power we used interdigitated electrodes that are coupled with a fractal tree antenna. In this paper, both semiconductor and electromagnetic problems are considered. Here, photomixer devices with Thue-Morse fractal tree antennas in two configurations (narrow and wide) are discussed. This new approach gives better performance, especially in the increasing of THz output power of photomixer devices, when compared with the conventional structures. In addition, applying the interdigitated electrodes improved THz photocurrent, considerably. It produces THz radiation power several times higher than the photomixers with simple gap.

Design of two by three element fractal tree antenna array for WLAN and WiFi applications

For more antenna miniaturization, novel fractal tree geometry designed for 5 iterations using rectangular and triangular patches that allow decrease in the resonance frequency without occupying more space. Impedance Matching can be improved without changing the main beam direction or current distribution to five iterations with branching half angle of 60 degrees. The antenna fed by a Coaxial or probe feed to improve the narrow bandwidth of Fractal Antenna. The proposed antenna achieves a bandwidth of 31.5% for 10 dB return loss, covering the frequency range 2.4–3.6 GHz for WLAN and WiFi applications. The antenna gain of the fractal element is about 3 dBi. Array is designed to increase the gain and radiation energy. Arrays are configured at operating frequency of 2.4 GHz by using six elements to enhance the gain up to 11 dBi. The obtained gain and frequency are suitable for WLAN and WiFi applications.

Continuous terahertz wave generation based on photomixers coupled to Fibonacci fractal tree antennas

A comprehensive analysis and numerical simulation of continuous wave terahertz (THz) generation based on photomixing is performed in this paper. For numerical investigation, both semiconductor and electromagnetic equations are considered. The effects of photomixer parameters and geometry of the antenna on terahertz power generation (photocurrent and radiated power) are investigated. In this work, for improving performance of the integrated antenna, the fractal tree antenna for two different geometries (the narrow and wide configurations) using the Fibonacci sequence is presented. We demonstrate that the fractal tree antenna with Fibonacci series arrangement in the both cases of narrow and wide configurations increases the THz radiation power more than twice in comparison to usual dipole antenna.

A novel design of hybrid fractal antenna using BFO

This paper presents a novel design of printed hybrid fractal tree (PHFT) antenna using bacterial forging optimization (BFO) in conjunction with curve fitting technique. The antenna geometry is based on the hybrid structure obtained by integrating meander line geometry with fractal tree, whose geometrical descriptors are determined by means of BFO. The fractal shape allows the new hybrid antenna to be effectively reduced in size without significantly impairing performance. Representative results of optimized antenna are reported in order to access the effectiveness of the developed approach for reliable implementation in wireless telemedicine applications. Moreover, useful guidelines on the effects of finite ground plane size on antenna characteristics have been adequately analyzed.

Design and optimization of new hybrid fractal tree antenna

An optimized design of printed hybrid fractal tree (PHFT) antenna based on binary fractal tree geometry is presented and discussed. In this paper miniaturization has been achieved by inserting a modified Koch curve in the conventional fractal binary tree. A comparative study shows that the new antenna provides 6.87% increase in radiation efficiency and 2.57% increase in antenna efficiency than conventional fractal tree antenna designed with similar dimensions. The geometrical descriptors of the proposed antenna have been synthesized using Bacterial Foraging Optimization (BFO) and Particle Swarm Optimization (PSO) for optimizing the values of electrical parameters within specifications. A performance comparison have also been done for both of these computational techniques which reveals that BFO gives better results in terms of accuracy than PSO for required working frequencies (5.2 GHz and 10.6 GHz). Representative results of optimized PHFT antenna for both simulations and experimental validations are reported in order to access the effectiveness of the developed approach for reliable implementation in wireless telemedicine applications.

The resonant behavior of the Fibonacci fractal tree antennas

AbstractAn investigation of a novel fractal tree antenna with the application to two different geometries is presented. The antenna is designed by using the special Fibonacci number sequence which leads to nonuniform branch length ratios to form the fractal tree. This new approach gives better performance, especially in the miniaturization of the antenna, when compared with the conventional designs. The results obtained from the experiments are also compared with the computed ones and there is a very good agreement between the numerical and measured data. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1046–1050, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23299

Miniature Reconfigurable Three-Dimensional Fractal Tree Antennas

This paper introduces a design methodology for miniature multiband as well as reconfigurable (i.e., tunable) antennas that exploits the self-similar branching structure of three-dimensional (3-D) fractal trees. Several fundamental relationships, useful for design purposes, are established between the geometrical structure of the fractal tree antenna and its corresponding radiation characteristics. In particular, it will be shown that the density and elevation angle of the branches play a key role in the effective design of miniature 3-D fractal tree antennas. Several design examples are considered where fractal trees are used as end-loads in order to miniaturize conventional dipole or monopole antennas. Multiband and reconfigurable versions of these miniature antennas are also proposed, where either reactive LC traps or RF switches are strategically placed throughout the branches and/or along the trunk of the trees. Included among these designs is a miniature reconfigurable dipole antenna that achieves a 57% size reduction for the center frequency of the lowest intended band of operation and has a tunable bandwidth of nearly 70%.

Multiband and wideband properties of printedfractal branched antennas

Multiband and wideband properties of printed fractal branched antennas The presented numerical and experimental results show that the input reflection coefficient relative to 50 Ω of a fractal tree antenna exhibits a multiband behaviour generated by the elements of successive iteration levels as well as a wideband response produced by the large number of elements of the last iteration level.

Multiband properties of a fractal tree antenna generatedby electrochemical deposition

Experimental results on a fractal tree-like antenna are reported. The fractal structure is generated by electrochemical deposition. The antenna presents a multiband behaviour with a denser band distribution than the previously reported Sierpinski fractal antenna. The matched frequencies are related to the length distribution over the fractal shape.