Convoluted Frequency Selective Surface Wallpaper to Block the Industrial, Scientific, and Medical Radio Bands Inside Buildings
Convoluted Frequency Selective Surface Wallpaper to Block the Industrial, Scientific, and Medical Radio Bands Inside Buildings
复制标题
DOI：
--
复制
发表时间：
2013-04
期刊：
影响因子：
--
通讯作者：
Hussein AlKayyali;N. Qasem
中科院分区：
文献类型：
--
作者：
Hussein AlKayyali;N. Qasem
摘要。本文报道了约旦Al-Ahliyya Amman大学完成的一个项目的一些发现。该项目是创建一个带阻方形环路和卷曲频率选择表面（FSS）墙纸。FSS壁纸作为一种最新技术，可以应用于墙壁上，通过阻挡所有不需要的室外传输，无论其来源如何，都可以阻断建筑物内2.4GHz频率的Wi-Fi频率（Taylor et al., 2011）。与设计的方环FSS相比，卷积FSS在不同入射波角度（0°-60°）下都能获得更好的性能，并且在横向电（TE）和横向磁（TM）入射波下都能达到稳定的谐振频率。所设计的FSS用于改善室内无线物理传播环境，降低干扰水平，从而增强建筑物中未经许可的2.4GHz工业，科学和医疗（ISM）无线电频段的网络安全性（Sung et al., 2006）。关键词：带阻，卷积，频率选择面，室内传播，仿真，方环路无线电信号通常通过反射，折射，衍射和散射传播。发射信号的分量以不同的幅度和相位值到达感兴趣的点，这些分量组合在一起产生接收信号。相邻系统之间的干扰是一个重要的问题，因为无线通信系统的使用迅速增长，特别是在未经许可的频段，如ISM频段。这种干扰不仅会降低系统的性能（Kartal, 2011），而且会影响传输系统的安全性（Batchelor et al., 2009）和（Mais et al., 2001）。从这个角度来看，它本质上是创造一种技术，在相邻系统使用的两个频率之间设置一个边界，以减少干扰，使系统有效地工作。问题是如何在2.4GHz频率上进行筛选，并给予其他频段最大的透明度。研究人员和科学家通过使用多种形状来开发FSS：负载偶极子、耶路撒冷交叉、三极子、交叉偶极子、偶极子和方环（Mais et al., 2001）。以往的研究表明，方环FSS在角不敏感、交叉极化TE或TM模式和小频带分离下具有最佳的响应和稳定性（Mais et al., 2001）。方环FSS越来越多地使用不同的结构和弯曲的形状，以提高FSS在频带阻塞滤波器中的性能（Qasem & Seager, 2012）。一般情况下，FSS结构在不同入射角下必须具有稳定的带阻滤波性能。此外，FSS必须对TE和TM极化波在（0 -60）角范围内表现出良好的频率稳定性（Qasem & Seager, 2010），信号最有可能在（0 -60）角范围内以显著强度到达地面（Sung et al., 2006）。为了提高室内环境下通信系统的效率，通过阻断室外2.4GHz频段，设计并仿真了一种FSS。为了阻挡来自室外环境的接收信号，在砖墙前放置了FSS壁纸。移动电话、电视、收音机和大多数通信系统通常使用低于2GHz的频率范围。这些频率仍然可以通过设计的FSS墙纸穿透被调查区域（Qasem & Seager, 2009）频率选择表面（FSS）频率选择表面（FSS）是一种表面，它表现出反射和/或传输特性作为频率的函数，换句话说，在谐振频率处的带阻FSS表现得像无线电信号的金属片（Sung etal ., 2006）。方环FSS，如图. ...所示
Abstract. This paper reports some of the findings in a project done at Al-Ahliyya Amman University in Jordan. The project was to create a band-stop square loop and convoluted frequency selective surface (FSS) wallpaper. FSS wallpaper as a state of the art that may be applicable on wall to block Wi-Fi frequency working on the 2.4GHz frequency inside buildings by blocking all unwanted outdoor transmissions, regardless their origin (Taylor et al., 2011). The convoluted FSS differs from the designed square loop FSS, by getting a better performance in presence of different incident angles of the propagating wave (0°-60°) and to reach a stable resonance frequency for both a transverse electric (TE) and a transverse magnetic (TM) incident waves. The designed FSS is used to modify the indoor wireless physical propagation environment and reducing the interference level which enhancing the network security with in the buldings in the unlicensed 2.4GHz, as industrial, scientific, and medical (ISM) radio bands (Sung et al., 2006).Keywords: Band-Stop, Convoluted, Frequency Selective Surface, Indoor Propagation, Simulation, Square Loop.1 INTRODUCTIONRadio signals generally propagate through reflections, refractions, diffractions, and scattering. Transmitted signal components arrive at the point of interest with various amplitude and phases values and these combine together to produce the received signal.Interference between neighboring systems is an important issue because of the rapid growth in the use of wireless communications systems, especially, in unlicensed bands such as the ISM band. This interference is not only degrading the system's performance (Kartal, 2011), but also compromising the transmitting system's security (Batchelor et al., 2009) & (Mais et al., 2001). From this point of view, it is essentially to create techniques that put a boundary between two frequencies used by neighboring systems which is reducing the interference in order to let the systems to work effectively.The problem is how to make a screening on 2.4GHz frequency and give the other bands the maximum transparency. Researchers and scientists were working on developing FSS by using many shapes: loaded dipole, Jerusalem cross, tripole, cross dipole, dipole, and square loop (Mais et al., 2001).Pervious researches showed that the square loop FSS has the best response and stability to work within the angular insensitivity, cross polarization TE or TM modes, and small band separation (Mais et al., 2001). Square loop FSS is used in an increasing way with different structures and convoluted shapes in order to enhance the figure of merit of FSS for band blocking filters (Qasem & Seager, 2012).In general case, the performance of FSS structures for different incidence angles of the propagating wave must exhibits stable band-stop filter. In addition, the FSS must show good frequency stability for both TE and TM polarized waves for angles from (0o-60o) (Qasem & Seager, 2010), where the signals are most likely to arrive at the surface between (0o-60o) with significant strength (Sung et al., 2006).To improve the efficiency of communication systems in an indoor environment by blocking the outdoor 2.4GHz, an FSS was designed and simulated. To block the received signal from outdoor environments, the FSS wallpaper placed in front of the brick wall. Mobile telephone, TV, radio, and the majority of communication systems generally use frequency ranges lower than 2GHz. These frequencies can still penetrate the investigated area via the designed FSS wallpaper (Qasem & Seager, 2009).2 FREQUENCY SELECTIVE SURFACES (FSS's)A Frequency Selective Surface (FSS) is a surface, which exhibits reflection and/or transmission properties as a function of frequency, in other word the band-stop FSS at the resonant frequency behaves like a metal sheet to radio signals (Sung et al., 2006).Square loop FSS, as shown in Fig. …