%0 Journal Article
%T Coplanar Waveguide-Fed Broadband Microwave Devices with (or without) a Thin Dielectric Substrate for Use in Flexible Electronic Systems
%A Rafal Lech
%A Wojciech Marynowski
%A Adam Kusiek
%A Jerzy Mazur
%J International Journal of Antennas and Propagation
%D 2014
%I Hindawi Publishing Corporation
%R 10.1155/2014/379379
%X Two examples of microwave devices, fed by a coplanar waveguide and realized on a thin substrate (or without such a substrate), are employed to investigate the influence of devices¡¯ curvatures and the proximity of different materials on their parameters. To perform the tests, a broadband antenna and a low-pass filter are chosen. A feeding coplanar waveguide is realized on a dielectric material brick attached to an SMA connector and the main device structure is placed in the air or on a thin substrate. The utilization of a thin substrate or its removal from the structure gives rise to the possibility of placing the devices on curved surfaces. The investigated devices are redesigned and manufactured. The antenna has a total size of 46£¿mm ¡Á 44£¿mm and covers a frequency range of 2.4¨C35£¿GHz which gives a 174% fractional bandwidth. The filter has a total size of 50£¿mm ¡Á 80£¿mm and its bandwidth has a cutoff frequency of 3.4£¿GHz. The obtained results are verified by measurements and good agreement is achieved. 1. Introduction The microwave components, including antennas and filters, used in mobile devices should not only operate within a specific frequency range but also have a compact and simple structure, with slight dimensions and a light weight. Besides the above requirements, their production costs, especially for large scale production, should also be as low as possible. When the device is designed on a thin and flexible layer, it can be bent and placed on curved surfaces. Conformal components (antennas especially) are becoming popular due to their many advantages and the possibilities of their application [1]. The advantages of using devices with a curved surface arise from the possibility of integrating them with the object on which they are mounted. In the case of conformal antennas, the particular advantage is the increase¡ªrelative to the planar antenna¡ªof their visible angular range. The conformal devices find application in a variety of fields, such as airborne, space-borne, ship-borne and missile-borne radar, space vehicles, wireless communication, and sonar. Besides the conformability of the flexible devices, they can find application and are becoming popular in the field of flexible electronics [2, 3]. The main requirements for such devices are light weight, low-cost manufacturing, ease of fabrication, and the availability of inexpensive flexible substrates (i.e., papers, textiles, and plastics). Many flexible antenna structures have been proposed in the literature (e.g., textiles with conducting threads [4] and paper-based [5], fluidic-based [6],
%U http://www.hindawi.com/journals/ijap/2014/379379/