Paulo Fernandes da Silva Junior

By Alexandre Jean René Serres, Georgina Karla de Freitas Serres, Paulo Fernandes da Silva Júnior, Raimundo Carlos Silvério Freire, Josiel do Nascimento Cruz, Tulio Chaves de Albuquerque, Maciel Alves Oliveira and Paulo Henrique da Fonseca Silva

In the last few years, bio‐inspired solutions have attracted the attention of the scientific community. Several world‐renowned institutions have sponsored and created laboratories in order to understand the forms, functions and behavior of living organisms. Some methods can be highlighted in the search for geometric representation of the shapes found in the nature, the fractal geometry, the polar geometry, and the superformula of Gielis. This chapter is focusing on bio‐inspired microstrip antennas, especially on leaf‐shaped antennas from the Gielis superformula that open a vast research field for more compact antennas with low visual impact.

Part of the book: Microstrip Antennas

By Paulo Fernandes da Silva Júnior, Alexandre Jean René Serres, Raimundo Carlos Silvério Freire, Georgina Karla de Freitas Serres, Edmar Candeia Gurjão, Joabson Nogueira de Carvalho and Ewaldo Eder Carvalho Santana

Due to the recent miniaturization of wireless devices, the use of wearable antennas is steadily increasing. A wearable antenna is intended to be a part of the clothing used for communication purposes. In this way, a lower visual cost may be achieved. Recently, biologically inspired design, a kind of design by cross-domain analogy is a promising paradigm for innovation as well as low visual cost. The shapes of the plants are structures optimized by nature with the primary goal of light energy capture, transforming it into chemical energy. In this case, they have similar behavior to that of parabolic reflectors; this enables microwave engineers design innovative antennas using bio-inspired concepts. One of the advantages of using bio-inspired plant shapes is the design of antennas with great perimeters in compact structures. Thus, we have small antennas operating in low frequencies. This chapter presents the recent development in bio-inspired wearable antennas, easily integrated to the clothes and accessories used by the body, built in denim, low-cost flexible dielectric, and polyamide flexible dielectric, that is flexible with high resistance to twists and temperatures, for wireless body area network (WBAN) applications, operating in cellular mobile (2G, 3G, and 4G) and wireless local area network (2.4 and 5 GHz) protocols.

Part of the book: Wearable Technologies

By Paulo Fernandes da Silva Junior, Mauro Sérgio Pinto Silva Filho, Ewaldo Eder de Carvalho Santana, Paulo Henrique da Fonseca Silva, Elder Eldervitch Carneiro de Oliveira, Maciel Alves de Oliveira, Fabrício Ferreira Batista, Alexandre Jean René Serres, Raimundo Carlos Silvério Freire, Almir Souza, Silva Neto, Severino Aires de Araújo Neto and Carlos Augusto de Moraes Cruz

This chapter presents the research done by authors in recent years on microstrip antennas and their applications in wireless sensors network. The subject is delimited to the study of conventional microstrip antennas, from which antennas with fractal and polar shapes are proposed. A detailed description of the antenna design methodology is presented for some prototypes of microstrip antennas manufactured with different dielectric substrates. Analysis of the proposed antennas has been done through computational simulation of full-wave methods. Experimental characterization of antennas and dielectric materials has been performed with the use of a vector network analyzer. The results obtained for the resonant and radiation parameters of the antennas are presented. Computer-aided design (CAD) of microstrip antennas and arrays using fractal and polar geometrical transformations results in a wide class of antenna elements with desirable and unique characteristics, such as compact, exclusive, and esthetic antenna design for multiband or broadband frequency operation with stable radiation pattern.

Part of the book: Wireless Mesh Networks