dc.contributor | Ricardo Luiz da Silva Adriano | |
dc.creator | Julio Cesar de Oliveira | |
dc.date.accessioned | 2019-08-14T05:09:51Z | |
dc.date.accessioned | 2022-10-03T22:52:24Z | |
dc.date.available | 2019-08-14T05:09:51Z | |
dc.date.available | 2022-10-03T22:52:24Z | |
dc.date.created | 2019-08-14T05:09:51Z | |
dc.date.issued | 2013-12-18 | |
dc.identifier | http://hdl.handle.net/1843/BUBD-9JHMJ2 | |
dc.identifier.uri | http://repositorioslatinoamericanos.uchile.cl/handle/2250/3812349 | |
dc.description.abstract | In this dissertation, uniform helical antennas are used as a starting point to generate nonuniform optimized antennas . Improvements in the gain and input impedance are obtained by varying the helix shape using a second order polynomial function. The the polynomial approximation coefficients are found using the deep-cut version of the ellipsoidal optimization algorithm. The use of the well known formulae and diagrams for the design of uniform helical antennas as a initial point of the deterministic method can reduce the search domain and provides a fast convergence rate. To simulate the behavior of the antennas, the Method of Moments (MoM) is applied to the Electric Field Integral Equation-EFIE. The antennas are fed using a Delta-Gap voltage source and the conducting plane at the base of the antennas are represented by the Image Theory. Results are presented for WiFi application using a center frequency of 2.45 GHz. It shows that the input impedance and the antenna length can be considerably improved using a simple and efficient parametrization. | |
dc.publisher | Universidade Federal de Minas Gerais | |
dc.publisher | UFMG | |
dc.rights | Acesso Aberto | |
dc.subject | Antenas helicoidais | |
dc.subject | Algorítimo elipsoidal deepcut | |
dc.subject | Método dos momentos | |
dc.subject | Otimização | |
dc.title | Projeto e otimização de antenas helicoidais não uniformes | |
dc.type | Dissertação de Mestrado | |