Shweta Rani

On the design and optimisation of new fractal antenna using PSO

An optimisation technique for newly shaped fractal structure using particle swarm optimisation with curve fitting is presented in this article. The aim of particle swarm optimisation is to find the geometry of the antenna for the required user-defined frequency. To assess the effectiveness of the presented method, a set of representative numerical simulations have been done and the results are compared with the measurements from experimental prototypes built according to the design specifications coming from the optimisation procedure. The proposed fractal antenna resonates at the 5.8 GHz industrial, scientific and medical band which is suitable for wireless telemedicine applications. The antenna characteristics have been studied using extensive numerical simulations and are experimentally verified. The antenna exhibits well-defined radiation patterns over the band.

Modified Koch fractal antenna with asymmetrical ground plane for multi and UWB applications

In this paper the proposed structure is based on a modified planar Koch curve antenna, whose geometrical parameters are determined by iterative function system algorithm for fractal curve generation. Compared with conventional antenna with same dimensions, modified Koch curve antenna provides additional frequency resonances. The asymmetrical ground plane has been optimized by means of bacterial foraging optimization (BFO) to make the proposed antenna feasible for wide band operation. In addition to miniaturization of about 40%, the optimized reference ground plane provides multi and ultra-wide band with high impedance matching throughout the frequency bands covering various wireless telemedicine applications. In order to assess the reliability of the antenna, measurements have been performed on the fabricated prototype and the obtained results shows good agreement with simulated results.

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.

A novel antenna design with fractal-shaped DGS using PSO for emergency management

This article presents an analysis and design of a novel planar antenna in corporation with fractal-shaped defected ground structure (DGS) for wireless communication devoted to emergency management. The conventional ground plane can be replaced by a fractal DGS ground plane to get size reduction, better efficiency and suppress surface-waves. The synthesis of the proposed antenna is carried out by means of particle swarm optimisation (PSO) to identify the geometrical descriptors of the structure. The representative results reveal that the proposed geometry exhibits better impedance matching and multiband characteristics in comparison to conventional planar antenna (without any defects). The analyses from simulations and numerical validations are reported in order to illustrate the effectiveness of varying scale factor that contributes 69.08% size reduction of ground plane.

A novel antenna design with DGS for emergency management

This paper presents an analysis and design of a novel planar antenna in corporation with fractal shaped defected ground structure (DGS) for wireless communication devoted to emergency management. The conventional ground plane can be replaced by a Fractal DGS ground plane to get size reduction, better efficiency and suppress surface-waves. The synthesis of proposed antenna is carried out by means of particle swarm optimization (PSO) to identify the geometrical descriptors of the structure. The representative results reveals that the proposed geometry exhibit better impedance matching and multiband characteristics in comparison to conventional planar antenna (without any defects). The analyses from simulations, numerical and experimental validations are reported in order to illustrate the effectiveness of varying scale factor that contributes 69.08% size reduction of ground plane.

Implementation of Fractal Geometry to Enhance the Bandwidth of CPW Fed Printed Monopole Antenna

ABSTRACT In this article, implementation of a plus shaped fractal geometry is proposed to broaden the impedance bandwidth of a co-planar waveguide (CPW) fed microstrip patch antenna. Compared to the reference antenna, the bandwidth of plus shaped fractal antenna is more than double (56% from 4.56 to 7.92 GHz covering most of the C-band) and size has been reduced by 11.36 %. Further, analysis of dimensional parameters of the co-planar ground plane has been examined critically in order to investigate its effect on antenna performance. Experiments have been performed on the fabricated antenna and the obtained results show a good agreement with the simulated results.

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.