IEEE Antennas and Propagation Society International Symposium. 1999 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.99CH37010)最新文献_第10页

Body-obstructed fading characteristics of an in-ward 2.45 GHz biomedical telecommand link 向内2.45 GHz生物医学遥控链路的体阻衰落特性

IEEE Antennas and Propagation Society International Symposium. 1999 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.99CH37010) Pub Date : 1999-07-11 DOI: 10.1109/APS.1999.789158

W. Scanlon, G. C. Crumley, N. Evans

{"title":"Body-obstructed fading characteristics of an in-ward 2.45 GHz biomedical telecommand link","authors":"W. Scanlon, G. C. Crumley, N. Evans","doi":"10.1109/APS.1999.789158","DOIUrl":"https://doi.org/10.1109/APS.1999.789158","url":null,"abstract":"The increasing use of short-range radio links for applications such as ward or home based physiological monitoring creates the need for a better knowledge and understanding of the indoor propagation environment. The work presented concerns a body-worn, cross-band UHF transponder used for physiological signaling within single-room environments. A modified image-based ray-tracing algorithm is used to calculate the fading characteristics for a link under the worst case condition, when the direct path between the source and chest-mounted receiver is obstructed by the body itself. The approach adopted utilizes a FDTD-generated radiation pattern of a realistic adult-male body model, incorporating the directional gains into the three-dimensional indoor ray-tracing algorithm. A description of the biomedical transponder is followed by details of the computational technique; path loss and small area fading results are then presented for a 76 m/sup 2/ area representing a hospital ward. The cumulative distribution function (CDF) results were found to be characteristically bi-modal and this novel feature is investigated in more detail.","PeriodicalId":391546,"journal":{"name":"IEEE Antennas and Propagation Society International Symposium. 1999 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.99CH37010)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130822235","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

An analysis and design tool for evaluation of integrated antenna diversity systems in portable wireless devices 便携式无线设备中集成天线分集系统评估的分析与设计工具

IEEE Antennas and Propagation Society International Symposium. 1999 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.99CH37010) Pub Date : 1999-07-11 DOI: 10.1109/APS.1999.788367

P. Irazoqui-Pastor, E. Swanson, C. Short, J. Bernhard

引用次数: 1

New class microwave antennas, based on the elements of the diffraction quasioptics: advantages and applications 基于衍射准光学原理的新型微波天线:优点与应用

IEEE Antennas and Propagation Society International Symposium. 1999 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.99CH37010) Pub Date : 1999-07-11 DOI: 10.1109/APS.1999.789424

I. Minin, O. Minin

{"title":"New class microwave antennas, based on the elements of the diffraction quasioptics: advantages and applications","authors":"I. Minin, O. Minin","doi":"10.1109/APS.1999.789424","DOIUrl":"https://doi.org/10.1109/APS.1999.789424","url":null,"abstract":"The concept of optical elements using diffraction is quite an old one; for instance, Fresnel's zone plate dates from about 1830. The elements of the diffraction quasioptics (EDQ) are intended for transformation of incident wavefronts into the required ones. The EDQ operation principle is based on creation of specifically chosen discrete phase delays over the wave front. There are three main types of EDQ (by the principle of disposition with respect to the propagation direction of the electromagnetic wave): transverse (made mainly on a flat surface), longitudinal-transverse (made on an arbitrary curvilinear surface) and longitudinal (representing a system of screens located along the direction of the electromagnetic wave propagation). The EDQ can operate both in the \"transmission regime\" and the \"reflection regime\". According to the application the EDQ can be of amplitude (binary) and phase inversion type. The main physical properties of the EDQ are surveyed in the present work. Different systems based on the EDQ are considered as well.","PeriodicalId":391546,"journal":{"name":"IEEE Antennas and Propagation Society International Symposium. 1999 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.99CH37010)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125440188","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: 3

Scattering of plane waves by two-dimensional periodic impedance surface 二维周期阻抗面对平面波的散射

IEEE Antennas and Propagation Society International Symposium. 1999 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.99CH37010) Pub Date : 1999-07-11 DOI: 10.1109/APS.1999.788328

R. Hwang, S. Peng

引用次数: 0

The scattering of an E-polarized plane wave from a metal strip on a ferrite circular rod 铁氧体圆棒上金属条发出的e偏振平面波的散射

IEEE Antennas and Propagation Society International Symposium. 1999 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.99CH37010) Pub Date : 1999-07-11 DOI: 10.1109/APS.1999.789260

K. Yashiro, N. Guan, S. Ohkawa

引用次数: 0

Planar handset antennas with electronically steerable parameters 平面手持天线与电子控制参数

IEEE Antennas and Propagation Society International Symposium. 1999 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.99CH37010) Pub Date : 1999-07-11 DOI: 10.1109/APS.1999.788369

P. Kabacik, A. Kucharski

{"title":"Planar handset antennas with electronically steerable parameters","authors":"P. Kabacik, A. Kucharski","doi":"10.1109/APS.1999.788369","DOIUrl":"https://doi.org/10.1109/APS.1999.788369","url":null,"abstract":"The primary objective of developments in wireless communications systems is to increase the density of subscribers simultaneously served by the system. Another major objective is to provide services where high rates of data transmission are needed. This can be achieved by extending the multiple access scheme and by improving channel modulation and coding. There are two major approaches to the multiple access scheme problem-the code division multiple access (CDMA) and the spatial division multiple access (SDMA). Their implementation calls for the use of smart antennas not only at the base station site, but also at the terminals, where antennas of an improved design are recommended. However, the functioning of smart antennas is still far from being well defined, and in this context a variety of concepts have been examined. This paper presents some results of our investigations into terminal antennas with improved properties of their radiation patterns. We focused on two properties-the optimized shape of the radiation pattern and the scanning of the main beam. These properties are needed to suppress interference. Furthermore, owing to the achieved antenna directivity it is feasible to suppress the scattered waves and to decrease intersymbol interference, which is a prerequisite to achieve a high data transmission rate. Unfortunately, each terminal antenna design must comply with the tough miniaturization requirements.","PeriodicalId":391546,"journal":{"name":"IEEE Antennas and Propagation Society International Symposium. 1999 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.99CH37010)","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126230264","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

On the aperture-coupled dielectric resonator antenna using a thick ground plane 采用厚地平面的孔耦合介质谐振器天线

IEEE Antennas and Propagation Society International Symposium. 1999 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.99CH37010) Pub Date : 1999-07-11 DOI: 10.1109/APS.1999.789386

K. Leung, Z. Chen, K. Luk, E. Yung

引用次数: 0

Contributions of T.T. Taylor to array synthesis 泰勒对阵列合成的贡献

IEEE Antennas and Propagation Society International Symposium. 1999 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.99CH37010) Pub Date : 1999-07-11 DOI: 10.1109/APS.1999.789268

R. Hansen

引用次数: 4

Numerical studies of diffraction by 2-D homogeneous and inhomogeneous dielectric wedges 二维均匀和非均匀介质楔衍射的数值研究

IEEE Antennas and Propagation Society International Symposium. 1999 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.99CH37010) Pub Date : 1999-07-11 DOI: 10.1109/APS.1999.789352

D. Demetriou, G. Stratis

{"title":"Numerical studies of diffraction by 2-D homogeneous and inhomogeneous dielectric wedges","authors":"D. Demetriou, G. Stratis","doi":"10.1109/APS.1999.789352","DOIUrl":"https://doi.org/10.1109/APS.1999.789352","url":null,"abstract":"Analytical expressions based on uniform theory of diffraction (UTD) are widely used in ray-tracing simulation tools for the diffraction problem. Although these theories predict the fields accurately in the far-field region for simple problems, it is difficult, if not impossible, to extend the analysis to find diffraction coefficients for wedges composed of dielectric and imperfectly conducting materials. In fact, the classical problem of diffraction from an infinite lossless dielectric wedge has not been solved analytically. In the past, we demonstrated the successful application of the FDTD method to numerically obtain diffraction coefficients for an infinite PEC wedge. In this paper, we use the FDTD method in a similar approach in order to find the electromagnetic field in the shadowing region of the inhomogeneous wedge. We further extend the FDTD approach to analyze parameter sensitivity for the diffracted fields from 2-D inhomogeneous material wedges representing practical cases, such as corners of different buildings with different type of inhomogeneities. This approach, in principle, can be extended to calculate the power in the shadowing region in three dimensions.","PeriodicalId":391546,"journal":{"name":"IEEE Antennas and Propagation Society International Symposium. 1999 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.99CH37010)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122222470","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: 0

A diagonal translation operator for the fast evaluation of two-dimensional transient wave fields 二维瞬态波场快速求值的对角平移算子

IEEE Antennas and Propagation Society International Symposium. 1999 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.99CH37010) Pub Date : 1999-07-11 DOI: 10.1109/APS.1999.789561

M. Lu, J. Wang, A. A. Ergin, A. Michielssen

引用次数: 2