Design and improvement of different characteristics of curved frequency selective surface

Abstract

Frequency Selective Surface (FSS) is a two dimensional array of patches on a dielectric material or that of apertures within a metallic screen. FSS has filtering properties according to its structure. It has various applications in modern communication fields such as radome technology, aircraft, satellite communication, modern building, household etc.[1-3]. FSS acts as a sub reflector and an absorber as per requirement of applications. [3-5].Different numerical methods such as Finite Difference Time Domain Method (FDTD), Finite Element Method (FEM) and Method of Moment (MOM) are used to analysis the FSS [2-3]. In May 1993, B. Philips, E. A. Parker et.al. analyzed a curved array with finite number of dipoles using the vector potential equation to compute the current distribution for each element [6]. There was only computational analysis. Jianxun Su and Xiaowen Xu analyzed various characteristics of planar and cylindrical curved FSS (strip model) with dipole arrays with the help of Method of Moments (MOM) based on the RWG basis functions [7] . In 1995, E. A. Parker et.al. informed about the interaction between an antenna and an enclosing FSS with curved free-standing arrays of dipoles using the Pocklington equation approach . Planar dipole elements were used as receiving antenna and other dipoles were arranged on dichroic enclosure to form curved FSS [8]. Researches on planar FSS become mature now a days, but still there is a narrow region of research works in curved FSSs. So, it is a provocation to design of a curved FSS with good transmission characteristics. To get rid of the various environmental hazarders, if the antenna of the radome is enclosed without affecting its performances, the concept of curved FSS has been introduced. Again in the year of 1996, E. A. Parker et.al. analyzed a very narrow band pass transmission responses with high angular stability of a flexible frequency-selective surfaces (FSSs) which was supported by dielectric substrate on both sides with different radius[9].