Design and manufacture of wideband antennas using additive manufacturing process

Abstract

The need for internet connection from anywhere and at all times, the demand for wireless data transmission services at transfer rates of gigabits per second, and the mass communication between machines (i.e., the popularization of Internet of Things) have required challenging characteristics of radiating systems in terms of dimensions, bandwidth, and gain. As a consequence, the complexity of the antenna geometry increases, requiring new and more efficient manufacturing techniques that generate less environmental impact. In the X band (8 to 12 GHz), helical antennas are widely used in mobile satellite communications. In the Ka-band (24.5 to 40GHz) an efficient option for point-multipoint coverage is the dual-reflector antennas with omnidirectional coverage fed by a coaxial horn. The present research project proposes the development of new models and prototypes of three antennas (helical, coaxial horn, and omnidirectional dual-reflector) using different fabrication techniques, in particular the additive manufacturing process. Firstly, antennas will be designed, analyzed using Ansys Electronic Desktop software, HFSS module (High-Frequency Structure Simulator) using the Finite Element Method (FEM) and optimized by Genetic Algorithms (GA). For helical antennas, the aim is to propose an alternative geometry that presents better electromagnetic performance (i.e., gain and reflection coefficient along with the operating band). For coaxial horn antenna, the objective is to propose a structure that presents radiation pattern stability in the operating bandwidth and, simultaneously (if possible), minimizes the reflection coefficient (parameter S11). The prototypes will be built using different manufacturing techniques: additive manufacturing (AM) of metals with selective laser fusion, MA in polymer with surface metallization by LTP (Low-Temperature Plasma), and CNC turning (Computer Numerical Command). The devices will have their electromagnetic performance assessed by measuring the reflection coefficient and radiation pattern. The environmental performance of the prototypes will be compared using the Life Cycle Assessment (LCA) technique, based on the standards ABNT ISO 14040: 2009 and ABNT ISO 14044: 2009 and through the software GaBi Student. Prototypes with the least potential for environmental impacts are considered to have the best environmental performance. This project has great potential for patenting both devices and manufacturing methods. (AU)