Antenna Miniaturization Using Fractals Richa Garg, AP ECE Deptt., [email protected], J.C.D.C.O.E., Sirsa ABSTRACTThe use of fractal geometry in designing antenna has been a resent topic of interest. Fractal shape has their own unique characteristics that the improved antenna performance can be achieved without degrading the antenna properties. Modern telecommunication system requires antenn...

This work presents a multiobjective genetic algorithm with a novel feature, the real biased crossover operator. This operator takes into account the function values of the two parents, defining a nonuniform probability for the new individuals’ locations that biases them toward the best parents’ locations. The procedure leads to better estimates of the Pareto set. The proposed algorithm is appli...

Approximate, non-singular kernels are often used in moment-method formulations coping with thin-wire structures. Their use has important consequences, one of which is the appearance of oscillations in the computed currents when the number of sub-domain basis functions is sufficiently large. These oscillations are not due to round-off errors. In this paper, a smoothing procedure is used in conju...

This papaer studies, from the point of view of the traveling-wave approach, the transient radiation by V-antennas including the dependence of the maximum directivity on the interior angle, on the length of the arms and on the characteristics of the exciting pulse. As particular examples, the cases when the antenna is excited by a harmonic signal and a gaussian pulse are analyzed and the results...

Fixed area meander line antennas designed on a 5 3 5 rectangular grid were optimized for efficiency and resonant frequency. The Pareto front was developed using ant colony optimization and the numerical electromagnetic code. The lowest frequency antenna fits an area of 0.11k0 3 0.05k0 with an efficiency of 88%. VC 2009 Wiley Periodicals, Inc. Int J RF and Microwave CAE 00: 000–000, 2009.

Single staggered is a design development of normal wire and tube heat exchanger that wires are welded with staggered configuration on two sides. Capacity of wire and tube heat exchanger is the ability of the heat exchanger to release heat. The objective of this study is to analyse the effect of wire pitch (pw) on capacity of single staggered wire and tube heat exchanger. The research...

The irregularity has been very attractive to the antenna and packaging engineers. More specifically, the self-similarity has inspired many researchers to use them for broadband designs, due to the fact that a fractal antenna is a repeated shape in different scales, which can be interpreted as a multiscale (“multi-wavelength”) radiator. In addition to this, the space filling property seems to be...