| The body-centric wireless communication network has become an important direction for the development of wireless communication in the future, which consists of wearable or implantable sensors. Textile antenna is one way to realize the body-centric wireless communication. Therefore, the study of the electromagnetic properties of fabric and textile antenna is of great practical significance. The antenna, weaved by the new fabric materials, has advantages of soft, light and easy to be shaped, so there will be broad application prospects in the aspects of civilian and military.Starting with the research of electromagnetic properties of the fabric, this thesis analyzes the weaving method of the fabric with the carrier of rectangular patch antenna, and then designs microstrip patch textile antenna, RFID tag textile antenna and digital TV textile antenna with the most suitable materials and structures. Finally, changes of the textile antenna are analyzed in a complex environment through experiments; the whole research process is combined with simulations and experiments. This paper includes the following four parts:Firstly, in order to be familiar with the principles and methods for electromagnetic simulation software, a miniature broadband impedance transformer is obtained through analysis and optimization with the help of ADS software, and the design process of the ADS software, optimization methods and calculation principle are in-depth understood to prepare for the simulation of textile antenna in the later period.Secondly, fabric of different widths are weaved using the materials of polyester and metal fibers, and the shielding effect of metal fabric is analyzed by testing different conditions of overlapping fabric to network structure. Meanwhile, phase parameters of the fabric are obtained by using stripline test fixture, the related formula derived from the theory of microstrip lines, and the effective dielectric constant of the fabric is acquired with inversion calculation.Thirdly, on the basis of the above research of the electromagnetic characteristics of the fabric, the thesis analyzes the types and characteristics of conductive fibers, and conducts the electromagnetic simulation and analysis for the rectangular microstrip patch antenna, then produces a variety of rectangular textile antenna, there are some differences in the conductive fiber material, thickness, weave density and structure, to explore the best way to weave the fabric. And then the optimal material and structure are gained by comparison and analysis. The patch antenna designed in this paper has a stable structure, good performance and achieves the desired functional requirements. It proves the feasibility to make antennas with fabric.Finally, according to the previous theory, the RFID tag antenna and digital TV textile antenna are designed; there are the differences of size and bandwidth between the two antennas. And some useful experience and conclusions are drawn by comparing and analyzing the different methods of making antenna with fabric. Meanwhile, taking into account the impact of some factors on the performance of the textile antenna, such as flexibility of the fabric, content and humidity of air, the simulation and analysis of textile antenna in a complex environment is also accomplished, frequency offset and other properties of unstable are found when any of these factors is changed. Therefore, the concept of integrated design is proposed to reduce these factors'impact on the performance of antenna and the reliability of the antenna is improved, so it brings a new feasible method for designing textile antenna.
|
PDF Full Text Request