2007 IEEE Antennas and Propagation Society International Symposium最新文献

The gap filler technology for mobile satellite system 移动卫星系统的间隙填充技术

2007 IEEE Antennas and Propagation Society International Symposium Pub Date : 2008-09-05 DOI: 10.1109/ASMS.2008.13

J. Ryu, M. Shin, S. Han, D. Jang, Hojin Lee

{"title":"The gap filler technology for mobile satellite system","authors":"J. Ryu, M. Shin, S. Han, D. Jang, Hojin Lee","doi":"10.1109/ASMS.2008.13","DOIUrl":"https://doi.org/10.1109/ASMS.2008.13","url":null,"abstract":"Satellite mobile communication systems have rapidly come into widespread use and user have begun to require high speed multimedia services in mobile environments in any place; even if high speed train. In response to these demands, mobile satellite communication system is the key solution to provide high speed multimedia services in high speed train. Nowadays the high speed portable system has been developed for example WiMAX, Wibro and so on. But these system can't provide high speed internet services because of the train speed. To figure out this problem, mobile satellite communication fits this environment. And mobile satellite communication system can play in a role of backhaul for WiMAX or Wibro system. But there is disadvantage in mobile satellite communication system, signal may suffer shadowing, power arche, trees and tunnels. Shadowing, power arches and trees degrades the network performance, it can be overcomed by use of packet FEC. But it is difficult to provide internet service in tunnel. To figure out this problem, we adopt the gap filler system which relay from/to satellite to/from terminal in tunnel. In this paper we introduce and compare the various types of gap filler, transparent and non-transparent types and finally how our gap filler system is configured.","PeriodicalId":117975,"journal":{"name":"2007 IEEE Antennas and Propagation Society International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128957297","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 7

Engineering lossy artificial dielectrics using single-walled carbon nanotubes 使用单壁碳纳米管的工程损耗人工电介质

2007 IEEE Antennas and Propagation Society International Symposium Pub Date : 2007-12-06 DOI: 10.1109/APS.2007.4396267

B. Glover, K. Whites

引用次数: 2

Development of a hemispherical near field antenna measurement range for use on a realistic ground 一种用于实际地面的半球形近场天线测量范围的研制

2007 IEEE Antennas and Propagation Society International Symposium Pub Date : 2007-12-06 DOI: 10.1109/APS.2007.4395826

E. Walton, T. Lee, G. Paynter, J. Snow, C. Buxton

引用次数: 3

Numerical diffraction synthesis of 2-D quasioptical power splitter 二维准光功率分路器的数值衍射合成

2007 IEEE Antennas and Propagation Society International Symposium Pub Date : 2007-12-06 DOI: 10.1109/APS.2007.4396406

A.A. Nosich, Y. Gandel, T. Magath, A. Altintas

引用次数: 0

Selective enhancement of mid-ir quantum dot electroluminescent emissions using defect mode photonic crystal cavities 利用缺陷模光子晶体腔选择性增强中红外量子点电致发光发射

2007 IEEE Antennas and Propagation Society International Symposium Pub Date : 2007-12-06 DOI: 10.1109/APS.2007.4395976

M. Su, I. El-Kady, E. Shaner, C. Christodoulou

引用次数: 1

Simulation of terrain propagation and diffraction using a 2D high-order accurate FMM-accelerated Nyström’s solver 利用二维高精度fmm加速Nyström求解器模拟地形传播和衍射

2007 IEEE Antennas and Propagation Society International Symposium Pub Date : 2007-07-23 DOI: 10.1109/IGARSS.2007.4422911

D. Liao, E. Michielssen, K. Sarabandi

引用次数: 5

Design of broadband slot antennas for circular polarization 圆极化宽带缝隙天线的设计

2007 IEEE Antennas and Propagation Society International Symposium Pub Date : 2007-06-09 DOI: 10.1109/APS.2007.4396090

Shao-Chang Lu, J. Row, C. Sim, Shiao-Wen Wu

{"title":"Design of broadband slot antennas for circular polarization","authors":"Shao-Chang Lu, J. Row, C. Sim, Shiao-Wen Wu","doi":"10.1109/APS.2007.4396090","DOIUrl":"https://doi.org/10.1109/APS.2007.4396090","url":null,"abstract":"It is well-known that the circular polarization (CP) bandwidth of a microstrip antenna is greatly related to its impedance characteristic. Several broadband antenna structures have been proposed and studied, such as using a thick substrate with low permittivity and a multi-resonator structure. Another method to enhance the impedance bandwidth is using slot antennas instead of the microstrip antennas. In this paper, a new CP design developed from the ring slot antenna is proposed. The antenna structure composed of a wide slot and a parasitic patch is with wideband characteristics. By adjusting the distance between the wide respectively, which are obviously higher than that of a same-size microstrip antenna. Also, the CP designs of wide slot antennas have been investigated to further improve the CP bandwidth. By protruding a T-shaped [3] or an L-shaped strip [4] from the ground plane, the CP bandwidth of the wide slot antenna can reach to 18 %. However, the available designs for the slot antenna with more than 20 % CP bandwidth are relatively few in the open articles. In this paper, a new CP design developed from the ring slot antenna is proposed. The antenna structure composed of a wide slot and a parasitic patch is with wideband characteristics. By adjusting the distance between the wide slot and parasitic patch, the CP bandwidth can be varied between 5 and 45%. Details of the proposed designs and the obtained results are shown and discussed.","PeriodicalId":117975,"journal":{"name":"2007 IEEE Antennas and Propagation Society International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115361828","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Empirical formula of effect on channel estimation error for adaptive MIMO-OFDM based WLAN system 自适应MIMO-OFDM无线局域网信道估计误差影响的经验公式

2007 IEEE Antennas and Propagation Society International Symposium Pub Date : 2007-06-09 DOI: 10.1109/APS.2007.4396170

W. Yamada, N. Kita, A. Ando

{"title":"Empirical formula of effect on channel estimation error for adaptive MIMO-OFDM based WLAN system","authors":"W. Yamada, N. Kita, A. Ando","doi":"10.1109/APS.2007.4396170","DOIUrl":"https://doi.org/10.1109/APS.2007.4396170","url":null,"abstract":"The IEEE802.11a standard for indoor wireless LAN systems was released commercially and is wide spread in the marketplace. To achieve higher throughput, IEEE802.11n was proposed and is now undergoing standardization. The MIMO-OFDM technique, which employs multiple antennas for transmission and reception, is the core technology for IEEE802.11n (Foshini and Gans, 1998). This technique requires estimation of channel state information (CSI) on the receiving side. Using the technique called adaptive MIMO-OFDM (Telatar, 1999) in which CSI is applied to both the transmitting and receiving sides, an even higher throughput is achieved. To achieve the maximum performance from adaptive MIMO-OFDM, we must accurately estimate the CSI for all the subcarriers; however, numerous calculations are needed to obtain this estimation. So, to actualize the adaptive MIMO-OFDM system, the calculation load must be decreased. This can be accomplished by applying one CSI to other subcarriers. However, channel error exists between the actual channel and the applied CSI. The channel error also plays a role in decreasing the communications quality (Medard, 2000). The communications quality when using the adaptive MIMO-OFDM technique that has CSI error was evaluated by simulation (Narula et al., 1998). However, there are few measurement evaluation reports on CSI error. This paper focuses on the ratio between the power of the eigenvalue and the interference power that suppresses the communication quality based on the measurement results. We propose an empirical formula for predicting the signal to interference ratio (SIR), which is the ratio between the power of the eigenvalue and the interference power. This SIR empirical formula helps to predict the communication quality and simplify the simulation.","PeriodicalId":117975,"journal":{"name":"2007 IEEE Antennas and Propagation Society International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115640192","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Further investigation of a dual-element diversity PIFA for MIMO applications at 2.5 GHz band 2.5 GHz频段MIMO应用双元分集PIFA的进一步研究

2007 IEEE Antennas and Propagation Society International Symposium Pub Date : 2007-06-09 DOI: 10.1109/APS.2007.4396129

Yue Gao, Xiao-dong Chen, Z. Ying, C. Parini

{"title":"Further investigation of a dual-element diversity PIFA for MIMO applications at 2.5 GHz band","authors":"Yue Gao, Xiao-dong Chen, Z. Ying, C. Parini","doi":"10.1109/APS.2007.4396129","DOIUrl":"https://doi.org/10.1109/APS.2007.4396129","url":null,"abstract":"Multiple input multiple output (MIMO) technology has been regarded as a practical approach to achieve significant increases of wireless channel capacity or reliability. Recently, the antenna's effect on MIMO system has been investigated intensively, in order to predict the true spectral efficiencies of MIMO systems in a real environment whereby realistic mobile terminals are used. Separation between multiple antenna elements is the most critical parameter affecting mutual coupling. Analytical studies have shown that for minimal or no mutual coupling, the distance between typical antenna elements needs to be at least half wavelength. However, the large separation between antenna elements is not attainable on a mobile terminal. There are a number of suggestions on how to build diversity antennas on a mobile terminal with low mutual coupling. In this context, we have developed a modified planar invert-F antenna (PIFA) and built a dual element array operating in 5.2GHz band with a separation of less than half wavelength (0.35 wavelength) and an isolation better than 28dB, as presented in our previous studies. It is noticed that mutual coupling depends on the frequency of received/transmitted signals since the distance is expressed in terms of the wavelength. Therefore, a dual-element diversity PIFA operating at the lower frequency (2.5GHz band) with an even closer separation (0.17 wavelength) has been studied in this paper.","PeriodicalId":117975,"journal":{"name":"2007 IEEE Antennas and Propagation Society International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123123402","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

A band-notched ultra-wideband 1 to 4 wilkinson power divider using symmetric defected ground structure 采用对称缺陷接地结构的带缺口超宽带1 ~ 4威尔金森功率分压器

2007 IEEE Antennas and Propagation Society International Symposium Pub Date : 2007-06-09 DOI: 10.1109/APS.2007.4395805

Yuan Yao, Zhenghe Feng

{"title":"A band-notched ultra-wideband 1 to 4 wilkinson power divider using symmetric defected ground structure","authors":"Yuan Yao, Zhenghe Feng","doi":"10.1109/APS.2007.4395805","DOIUrl":"https://doi.org/10.1109/APS.2007.4395805","url":null,"abstract":"In this paper, we propose a novel ultra-wideband Wilkinson power divider with symmetric defected ground structure (DGS) having frequency band-notch characteristic. The Wilkinson power divider was invented in 1960 and has wide applications in microwave circuits and antenna feeds. But it has a narrow bandwidth. Several schemes have been devised to increase its bandwidth. The main proposal used series connection of several sections having considerably increased bandwidth and high isolation between outputs for equal power divider. We use connection of three sections to obtain the UWB Wilkinson power divider. It is well known that the DGS of the microstrip line is implemented by making artificial defect on the ground and the ground defect provides a resonance property in transfer characteristic. In the microstrip line, DGS on the ground plane provides band rejection characteristic at some resonance frequency corresponding to the size of defect on the ground. In this paper, band-notch characteristic is achieved by inserting a symmetric spiral DGS under the microstrip line of the power divider. Experimental results of the constructed prototype are presented.","PeriodicalId":117975,"journal":{"name":"2007 IEEE Antennas and Propagation Society International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124399357","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 18