Pub Date : 2006-03-06DOI: 10.1109/IWAT.2006.1609026
B. Collins
The designers of handsets for mobile radio networks are subject to pressures to integrate more and more functionality into handsets whose dimensions, led by the expectations of the market, shrink with each new generation of designs. This pressure is accentuated by the demand for power created by large colour displays and cameras, while the dimensions available for batteries are stringently limited. On examining the link budget for a mobile radio system it is very obvious that the low gain of a typical handset antenna is an area capable of significant improvement. For the network operator the modest RF performance of handsets limits their coverage, while for the user it not only degrades the service they enjoy, but also significantly diminishes battery life (talk time). This article discusses the important interactions between aspects of the design of the handset and the RF performance which can be obtained from it. As will be seen, acceptable RF performance is not just a matter for the antenna designer, but depends on an understanding of the underlying issues on the part of the whole handset design team.
{"title":"Improving the RF Performance of Clamshell Handsets","authors":"B. Collins","doi":"10.1109/IWAT.2006.1609026","DOIUrl":"https://doi.org/10.1109/IWAT.2006.1609026","url":null,"abstract":"The designers of handsets for mobile radio networks are subject to pressures to integrate more and more functionality into handsets whose dimensions, led by the expectations of the market, shrink with each new generation of designs. This pressure is accentuated by the demand for power created by large colour displays and cameras, while the dimensions available for batteries are stringently limited. On examining the link budget for a mobile radio system it is very obvious that the low gain of a typical handset antenna is an area capable of significant improvement. For the network operator the modest RF performance of handsets limits their coverage, while for the user it not only degrades the service they enjoy, but also significantly diminishes battery life (talk time). This article discusses the important interactions between aspects of the design of the handset and the RF performance which can be obtained from it. As will be seen, acceptable RF performance is not just a matter for the antenna designer, but depends on an understanding of the underlying issues on the part of the whole handset design team.","PeriodicalId":162557,"journal":{"name":"IEEE International Workshop on Antenna Technology Small Antennas and Novel Metamaterials, 2006.","volume":"83 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116230286","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}
Pub Date : 2006-03-06DOI: 10.1109/IWAT.2006.1609065
K. Sato, S. Matsuzawa, Y. Inoue, T. Nomura
In the past few years, there has been significant interest in automotive radar for pre-crash safety and adaptive cruise control systems [1], [2] using a millimeter-wave band from 76 GHz to 77 GHz. In the systems, the beam is electronically scanned in the azimuth angle to detect vehicles and obstacles. Wide beam scanning and high gain are required as the radar antenna systems. Furthermore, compact size and low cost are important for automotive applications. The left-handed leaky wave antenna (LHLWA) is able to scan the beam widely because it supports both backward and forward waves [3]. However, the conventional frequency-dependent LWLHAs are not practical for the automotive radar antenna systems. In order to overcome this drawback, much effort has been made in developing the frequency-independent LWLHAs. An electronically and continuously scanned LWLHA using the varactor diodes was presented [4], but the diodes are too lossy to use in the millimeter-wave band. Moreover, it is difficult to fabricate high gain array antennas which have hundreds of unit cells and diodes. As other problems of the conventional LHLWAs, antenna gain is not enough for radar applications because the aperture amplitude distribution of the array antennas cannot be controlled well. We have proposed a novel structure of LHLWA, which can steer the radiation angle at a fixed frequency. The antenna includes a dielectric material, which locally changes its dielectric constant in response to an external stimulus. Liquid crystal has attractive properties such as a low electric command and weak losses in the millimeter-wave band. Moreover, slots are added to the LHLWA to control the aperture amplitude distribution of the array antennas.
{"title":"Electronically Scanned Left-Handed Leaky Wave Antenna for Millimeter-Wave Automotive Applications","authors":"K. Sato, S. Matsuzawa, Y. Inoue, T. Nomura","doi":"10.1109/IWAT.2006.1609065","DOIUrl":"https://doi.org/10.1109/IWAT.2006.1609065","url":null,"abstract":"In the past few years, there has been significant interest in automotive radar for pre-crash safety and adaptive cruise control systems [1], [2] using a millimeter-wave band from 76 GHz to 77 GHz. In the systems, the beam is electronically scanned in the azimuth angle to detect vehicles and obstacles. Wide beam scanning and high gain are required as the radar antenna systems. Furthermore, compact size and low cost are important for automotive applications. The left-handed leaky wave antenna (LHLWA) is able to scan the beam widely because it supports both backward and forward waves [3]. However, the conventional frequency-dependent LWLHAs are not practical for the automotive radar antenna systems. In order to overcome this drawback, much effort has been made in developing the frequency-independent LWLHAs. An electronically and continuously scanned LWLHA using the varactor diodes was presented [4], but the diodes are too lossy to use in the millimeter-wave band. Moreover, it is difficult to fabricate high gain array antennas which have hundreds of unit cells and diodes. As other problems of the conventional LHLWAs, antenna gain is not enough for radar applications because the aperture amplitude distribution of the array antennas cannot be controlled well. We have proposed a novel structure of LHLWA, which can steer the radiation angle at a fixed frequency. The antenna includes a dielectric material, which locally changes its dielectric constant in response to an external stimulus. Liquid crystal has attractive properties such as a low electric command and weak losses in the millimeter-wave band. Moreover, slots are added to the LHLWA to control the aperture amplitude distribution of the array antennas.","PeriodicalId":162557,"journal":{"name":"IEEE International Workshop on Antenna Technology Small Antennas and Novel Metamaterials, 2006.","volume":"89 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121257291","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}
Pub Date : 2006-03-06DOI: 10.1109/IWAT.2006.1609046
N. Chavannes, P. Futter, R. Tay, K. Pokovic, N. Kuster
The objective of this study was to evaluate whether the performance of mobile phones can be reliably predicted by numerical methods. It has previously been demonstrated [1, 3] that performance can be accurately assessed for standardized testing positions at the head. In this study, the requirements were extended to actual usage patterns such as different positions at the head and especially for different ways of holding the phone with the hand. The latter is of particular importance because fingers placed at certain locations could strongly affect the antenna.
{"title":"Reliable prediction of mobile phone performance for different daily usage patterns using the FDTD method","authors":"N. Chavannes, P. Futter, R. Tay, K. Pokovic, N. Kuster","doi":"10.1109/IWAT.2006.1609046","DOIUrl":"https://doi.org/10.1109/IWAT.2006.1609046","url":null,"abstract":"The objective of this study was to evaluate whether the performance of mobile phones can be reliably predicted by numerical methods. It has previously been demonstrated [1, 3] that performance can be accurately assessed for standardized testing positions at the head. In this study, the requirements were extended to actual usage patterns such as different positions at the head and especially for different ways of holding the phone with the hand. The latter is of particular importance because fingers placed at certain locations could strongly affect the antenna.","PeriodicalId":162557,"journal":{"name":"IEEE International Workshop on Antenna Technology Small Antennas and Novel Metamaterials, 2006.","volume":"200 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124481133","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}
Pub Date : 2006-03-06DOI: 10.1109/IWAT.2006.1609034
L. Guo, J. Liang, X. Chen, C. Parini
In this paper, a time domain study of Artimi's UWB antenna is presented. Firstly, the antenna's frequency domain behavior is illustrated. Thereafter, a detailed time domain investigation of the antenna is highlighted. It has been shown that Artimi's UWB antenna generally exhibits a good performance in both frequency and time domain. Wireless communications have been advancing with an astonishing rate during the last decade and wireless devices for future applications are required to offer manifold services like video, speech, data, and so on. This uprising demand accelerates the need for antennas capable of covering multiple bands or an ultra wideband for various systems. Since the Federal Communications Commission (FCC) released a bandwidth of 7.5 GHz for ultra wideband (UWB) applications, UWB has been evolving as a wireless technology of high potential. And UWB antennas have consequently attracted more and more attention from both academia and industries worldwide. However, unlike conventional narrow band antennas, design and analysis of UWB antennas are confronting more challenges. Some elemental antenna parameters need to be re-addressed or re-evaluated within the UWB definition scope. And due to UWB's unique features, there is a necessity to study UWB antennas from both the time and frequency domain perspective (1)-(3). In this paper, a UWB antenna developed by Artimi Ltd is investigated experimentally. Firstly, the frequency domain behavior of the antenna is described. And transient characteristics of the antenna are studied next. To explore more in detail the time domain behavior of the antenna, various measurements for different antenna pair orientations were performed. It has been demonstrated that Artimi's antenna generally exhibits a good performance in both frequency and time domain. II FREQUENCY DOMAIN BEHAVIOR OF ARTIMI'S UWB ANTENNA The antenna investigated in this paper is a printed dipole on both sides of the printed-circuit-board (PCB), as shown in Fig. 1. The antenna design is the intellectual property of Artimi Ltd (www.artimi.com) and is patented and copyrighted. More structural details about this antenna can be found from Artimi Ltd (4). Fig. 2 illustrates the measured return loss curve. As can be seen from the plot, this antenna can provide a satisfactory ultra wide frequency bandwidth.
{"title":"Time Domain Behaviors of Artimi's UWB Antenna","authors":"L. Guo, J. Liang, X. Chen, C. Parini","doi":"10.1109/IWAT.2006.1609034","DOIUrl":"https://doi.org/10.1109/IWAT.2006.1609034","url":null,"abstract":"In this paper, a time domain study of Artimi's UWB antenna is presented. Firstly, the antenna's frequency domain behavior is illustrated. Thereafter, a detailed time domain investigation of the antenna is highlighted. It has been shown that Artimi's UWB antenna generally exhibits a good performance in both frequency and time domain. Wireless communications have been advancing with an astonishing rate during the last decade and wireless devices for future applications are required to offer manifold services like video, speech, data, and so on. This uprising demand accelerates the need for antennas capable of covering multiple bands or an ultra wideband for various systems. Since the Federal Communications Commission (FCC) released a bandwidth of 7.5 GHz for ultra wideband (UWB) applications, UWB has been evolving as a wireless technology of high potential. And UWB antennas have consequently attracted more and more attention from both academia and industries worldwide. However, unlike conventional narrow band antennas, design and analysis of UWB antennas are confronting more challenges. Some elemental antenna parameters need to be re-addressed or re-evaluated within the UWB definition scope. And due to UWB's unique features, there is a necessity to study UWB antennas from both the time and frequency domain perspective (1)-(3). In this paper, a UWB antenna developed by Artimi Ltd is investigated experimentally. Firstly, the frequency domain behavior of the antenna is described. And transient characteristics of the antenna are studied next. To explore more in detail the time domain behavior of the antenna, various measurements for different antenna pair orientations were performed. It has been demonstrated that Artimi's antenna generally exhibits a good performance in both frequency and time domain. II FREQUENCY DOMAIN BEHAVIOR OF ARTIMI'S UWB ANTENNA The antenna investigated in this paper is a printed dipole on both sides of the printed-circuit-board (PCB), as shown in Fig. 1. The antenna design is the intellectual property of Artimi Ltd (www.artimi.com) and is patented and copyrighted. More structural details about this antenna can be found from Artimi Ltd (4). Fig. 2 illustrates the measured return loss curve. As can be seen from the plot, this antenna can provide a satisfactory ultra wide frequency bandwidth.","PeriodicalId":162557,"journal":{"name":"IEEE International Workshop on Antenna Technology Small Antennas and Novel Metamaterials, 2006.","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122895340","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}
Pub Date : 2006-03-06DOI: 10.1109/IWAT.2006.1609043
Kyung‐Young Jung, B. Donderici, F. Teixeira
Nonreciprocal magnetic photonic crystals (MPCs) are dispersion engineered metamaterials that exhibit unique properties such as electromagnetic unidirectionality and frozen modes with zero group velocity [1], [2]. Nonreciprocal MPCs are periodic structures composed of misaligned anisotropic dielectric layers (A-layers) and ferromagnetic layers (F-layers), as shown in Fig. 1. MPCs with a proper choice of geometry and tensor parameters can display asymmetric dispersion relation ω(k) with a stationary inflection point (SIP) in a forward direction and no SIP in a backward direction [1]. Since group velocities are extremely low near the SIP, EM waves seem to be “frozen” inside nonreciprocal MPCs in the forward direction; at the same time, forward propagating EM pulses can exhibit a dramatic growth in amplitude inside the MPC. In the backward direction, EM waves inside the MPCs propagate in an ordinary fashion [2].
{"title":"PML-FDTD Analysis of Nonreciprocal Magnetic Photonic Crystals with Ferromagnetic Losses","authors":"Kyung‐Young Jung, B. Donderici, F. Teixeira","doi":"10.1109/IWAT.2006.1609043","DOIUrl":"https://doi.org/10.1109/IWAT.2006.1609043","url":null,"abstract":"Nonreciprocal magnetic photonic crystals (MPCs) are dispersion engineered metamaterials that exhibit unique properties such as electromagnetic unidirectionality and frozen modes with zero group velocity [1], [2]. Nonreciprocal MPCs are periodic structures composed of misaligned anisotropic dielectric layers (A-layers) and ferromagnetic layers (F-layers), as shown in Fig. 1. MPCs with a proper choice of geometry and tensor parameters can display asymmetric dispersion relation ω(k) with a stationary inflection point (SIP) in a forward direction and no SIP in a backward direction [1]. Since group velocities are extremely low near the SIP, EM waves seem to be “frozen” inside nonreciprocal MPCs in the forward direction; at the same time, forward propagating EM pulses can exhibit a dramatic growth in amplitude inside the MPC. In the backward direction, EM waves inside the MPCs propagate in an ordinary fashion [2].","PeriodicalId":162557,"journal":{"name":"IEEE International Workshop on Antenna Technology Small Antennas and Novel Metamaterials, 2006.","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123257764","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}
Pub Date : 2006-03-06DOI: 10.1109/IWAT.2006.1609040
Yong Liu, K. Contractor, Yun Yuan
Antenna polarization is a very important consideration when choosing and designing an antenna. The far field energy radiated by any antenna is contained in a transverse electromagnetic wave that is comprised of an electric and a magnetic field. These fields, like a plane wave, are always orthogonal to one another and orthogonal to the direction of propagation. In a specified direction from an antenna and at a point in its far field, the polarization of the local plane wave defines the polarization of an antenna in a specified direction [1]. The polarization of a plane wave is defined according to the locus of the tip of its electric field vector, [2] with the ratio of the magnitude of the major and minor axes of the ellipse determining the type of polarization. In general, all electromagnetic waves are elliptically polarized. Axial ratio, tilt angle and the sense of polarization are frequently used terms to describe the state of polarization. The Axial Ratio (AR) is the ratio of the major axis to the minor axis of the polarization ellipse. Two special cases of elliptical polarization are linear and circular polarization. When the minor axis tends towards zero, the ellipse changes into a line segment that is orientated along the major axis. This is effectively called linear polarization and the axial ratio is ∞. If the major axis and minor axis are identical, the polarization ellipse becomes a circle and its axial ratio would be±1. The sign indicates the sense of the rotation, Left Hand Circular Polarization or Right Hand Circular Polarization. The tilt angle is the angle measured clockwise from the reference line to the major axis [1]. Generally, the type and the orientation of polarization varies with different values of θ and φ. (angles that define the observation position) Therefore, in order to completely describe the polarization of an antenna, four parameters (θ, φ, axial ratio and tilt angle) are needed. There are various methods to display the polarization of an antenna. The Poincaré sphere is a frequently used tool to represent polarization. However, the directional information cannot be displayed on this sphere. Wolfgang-Martin Boerner et al. projected the surface of the Poincaré sphere onto a complex plane, so the entire sphere could be displayed and mapped onto the same plane [3]. Harry Mieras used equal area projection of the Poincaré sphere to display polarization [4]. Georges A. Deschamps and P. Edward Mast improved the Poincaré sphere representation by introducing points inside the sphere to represent partially polarized states [5]. George H. Knittle introduced polarization charts, which are stereographic projections of a Poincaré sphere [6], to investigate polarization. Thus, although the Poincaré sphere and its projection can describe the polarization at a certain set of observation parameters precisely, it is unable to display global polarization information of antenna in all directions. Furthermore, some projections are not ve
天线极化是选择和设计天线时非常重要的考虑因素。任何天线辐射的远场能量都包含在一个由电场和磁场组成的横向电磁波中。这些场，就像平面波一样，总是彼此正交，并且与传播方向正交。从天线出发，在指定方向上，在天线远场的某一点上，局部平面波的极化决定了天线在指定方向上的极化[1]。平面波的偏振是根据其电场矢量尖端的轨迹来定义的，[2]用椭圆长轴和短轴的大小之比来决定偏振的类型。一般来说，所有的电磁波都是椭圆极化的。轴比、倾斜角度和偏振感是描述偏振状态的常用术语。轴比(AR)是偏振椭圆的长轴与短轴的比值。椭圆偏振的两种特殊情况是线偏振和圆偏振。当短轴趋向于零时，椭圆变为沿长轴方向的线段。这实际上被称为线偏振，轴向比是∞。当长、短轴相同时，极化椭圆为圆，其轴比为±1。标志表明旋转的意义，左手圆偏振或右手圆偏振。倾斜角是从参考线到长轴顺时针测量的角度[1]。通常，极化的类型和取向随θ和φ值的不同而变化。因此，为了完整地描述天线的极化，需要四个参数(θ、φ、轴比和倾角)。显示天线极化的方法有很多种。庞加莱球是一个经常被用来表示极化的工具。但是，在这个球体上不能显示方向信息。Wolfgang-Martin Boerner等人将poincar球的表面投影到复平面上，从而可以将整个球显示并映射到同一平面上[3]。Harry Mieras使用庞加莱球的等面积投影来显示偏振[4]。Georges A. Deschamps和P. Edward Mast通过在球内引入点来表示部分极化状态，改进了庞卡勒球表示[5]。George H. Knittle引入偏振图来研究偏振，偏振图是庞加莱球的立体投影[6]。因此，虽然庞加莱球及其投影可以精确地描述某一观测参数下的极化，但无法显示天线在各个方向上的全局极化信息。此外，有些预测并不容易理解。比较Eθ和Eφ(电远场的正交分量)的走线也可以提供有关极化的信息。以前的方法都不能同时显示所有四个参数。任意天线的轴比和倾角会随着观测角度的变化而变化，不方便判断其复杂极化情况。大多数制造商指定的轴向比在天线的轴视或在一个角度范围内的最大值，通常选择代表天线的主波束。从不同的观测角度，我们可以得到不同的ar，从而得到不同的极化。本文所描述的方法可以直观地显示天线在不同观测角度下的极化特性，这对于了解天线的整体极化特性是必要的。
{"title":"A Method to Display Complicated Polarization of An Arbitrary Antenna","authors":"Yong Liu, K. Contractor, Yun Yuan","doi":"10.1109/IWAT.2006.1609040","DOIUrl":"https://doi.org/10.1109/IWAT.2006.1609040","url":null,"abstract":"Antenna polarization is a very important consideration when choosing and designing an antenna. The far field energy radiated by any antenna is contained in a transverse electromagnetic wave that is comprised of an electric and a magnetic field. These fields, like a plane wave, are always orthogonal to one another and orthogonal to the direction of propagation. In a specified direction from an antenna and at a point in its far field, the polarization of the local plane wave defines the polarization of an antenna in a specified direction [1]. The polarization of a plane wave is defined according to the locus of the tip of its electric field vector, [2] with the ratio of the magnitude of the major and minor axes of the ellipse determining the type of polarization. In general, all electromagnetic waves are elliptically polarized. Axial ratio, tilt angle and the sense of polarization are frequently used terms to describe the state of polarization. The Axial Ratio (AR) is the ratio of the major axis to the minor axis of the polarization ellipse. Two special cases of elliptical polarization are linear and circular polarization. When the minor axis tends towards zero, the ellipse changes into a line segment that is orientated along the major axis. This is effectively called linear polarization and the axial ratio is ∞. If the major axis and minor axis are identical, the polarization ellipse becomes a circle and its axial ratio would be±1. The sign indicates the sense of the rotation, Left Hand Circular Polarization or Right Hand Circular Polarization. The tilt angle is the angle measured clockwise from the reference line to the major axis [1]. Generally, the type and the orientation of polarization varies with different values of θ and φ. (angles that define the observation position) Therefore, in order to completely describe the polarization of an antenna, four parameters (θ, φ, axial ratio and tilt angle) are needed. There are various methods to display the polarization of an antenna. The Poincaré sphere is a frequently used tool to represent polarization. However, the directional information cannot be displayed on this sphere. Wolfgang-Martin Boerner et al. projected the surface of the Poincaré sphere onto a complex plane, so the entire sphere could be displayed and mapped onto the same plane [3]. Harry Mieras used equal area projection of the Poincaré sphere to display polarization [4]. Georges A. Deschamps and P. Edward Mast improved the Poincaré sphere representation by introducing points inside the sphere to represent partially polarized states [5]. George H. Knittle introduced polarization charts, which are stereographic projections of a Poincaré sphere [6], to investigate polarization. Thus, although the Poincaré sphere and its projection can describe the polarization at a certain set of observation parameters precisely, it is unable to display global polarization information of antenna in all directions. Furthermore, some projections are not ve","PeriodicalId":162557,"journal":{"name":"IEEE International Workshop on Antenna Technology Small Antennas and Novel Metamaterials, 2006.","volume":"54 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123459981","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}
Pub Date : 2006-03-06DOI: 10.1109/IWAT.2006.1609055
D. Mastela, L. Reindl, L. Wiebking, L. Zander
Multipath propagation is a real challenge for radio tracking and RFID systems. The multipath effects that occur under severe propagation conditions (many metal objects) can become crucial for performance of such systems. The transmitted signal and its replicas reach a base station at slightly different times as a result of reflections. These short multi-path reflections can overlap with a line-of-sight signal causing a significant deterioration of range measurement. The use of omni-directional antennas creates the most opportunities for this kind of signal degradation.
{"title":"Development of a Cylindrical Microstrip Phased Array Antenna for a Radio Tracking System","authors":"D. Mastela, L. Reindl, L. Wiebking, L. Zander","doi":"10.1109/IWAT.2006.1609055","DOIUrl":"https://doi.org/10.1109/IWAT.2006.1609055","url":null,"abstract":"Multipath propagation is a real challenge for radio tracking and RFID systems. The multipath effects that occur under severe propagation conditions (many metal objects) can become crucial for performance of such systems. The transmitted signal and its replicas reach a base station at slightly different times as a result of reflections. These short multi-path reflections can overlap with a line-of-sight signal causing a significant deterioration of range measurement. The use of omni-directional antennas creates the most opportunities for this kind of signal degradation.","PeriodicalId":162557,"journal":{"name":"IEEE International Workshop on Antenna Technology Small Antennas and Novel Metamaterials, 2006.","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132213859","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}
Pub Date : 2006-03-06DOI: 10.1109/IWAT.2006.1609007
A. Mirkamali, P. Hall, M. Soleimani
Reconfigurable antennas have received a great deal of attention for their applications in wireless communications in recent years. They can be used for changing the operation frequency [1]-[6] or changing the radiation pattern [7]-[9]. In [1] a reconfigurable microstrip antenna was designed by placing MEMS series switches at the radiating edge. The series switches connect extra sections of transmission line to the microstrip antenna, thereby lowering its resonant frequency. In [2] a micromachined membrane was used as the ground plane below the microstrip patch antenna to design a frequency-agile patch antenna. In [3] a square patch antenna with switchable slots was proposed for dual band circular polarization operation. A dual band dipole using series MEMS switches was presented in [4] and a dual band reconfigurable Yagi antenna in [5]. A single-fed resonant slot, loaded with a series of PIN diodes switches, was designed in [6]. In [7] it was shown that by using RF switches the radiation pattern of the Hilbert curve fractal antenna could be made adaptively reconfigurable and also resonance frequency of the antenna was tunable by using the switches. In [8] a beam-switched Rhombic antenna was proposed. In [9] a reconfigurable single turn square microstrip spiral antenna was presented which can be reconfigurable in radiation pattern and frequency.
{"title":"Wideband Reconfigurable Printed Dipole Antenna with Harmonic Trap","authors":"A. Mirkamali, P. Hall, M. Soleimani","doi":"10.1109/IWAT.2006.1609007","DOIUrl":"https://doi.org/10.1109/IWAT.2006.1609007","url":null,"abstract":"Reconfigurable antennas have received a great deal of attention for their applications in wireless communications in recent years. They can be used for changing the operation frequency [1]-[6] or changing the radiation pattern [7]-[9]. In [1] a reconfigurable microstrip antenna was designed by placing MEMS series switches at the radiating edge. The series switches connect extra sections of transmission line to the microstrip antenna, thereby lowering its resonant frequency. In [2] a micromachined membrane was used as the ground plane below the microstrip patch antenna to design a frequency-agile patch antenna. In [3] a square patch antenna with switchable slots was proposed for dual band circular polarization operation. A dual band dipole using series MEMS switches was presented in [4] and a dual band reconfigurable Yagi antenna in [5]. A single-fed resonant slot, loaded with a series of PIN diodes switches, was designed in [6]. In [7] it was shown that by using RF switches the radiation pattern of the Hilbert curve fractal antenna could be made adaptively reconfigurable and also resonance frequency of the antenna was tunable by using the switches. In [8] a beam-switched Rhombic antenna was proposed. In [9] a reconfigurable single turn square microstrip spiral antenna was presented which can be reconfigurable in radiation pattern and frequency.","PeriodicalId":162557,"journal":{"name":"IEEE International Workshop on Antenna Technology Small Antennas and Novel Metamaterials, 2006.","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132398630","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}
Pub Date : 2006-03-06DOI: 10.1109/IWAT.2006.1609011
N. Komjani, M. Ostadrahimi
y increasing demand for multi-frequency services in communication, the need for compact and multi-band antennas has been growing recently. Microstrip patch antennas for their special characteristics such as low profile, light weight, conformity and ease of fabrication are widely used. They are manufactured in many different shapes and geometries. Among them, H-shaped microstrip antennas are one of compact structures which have been investigated by Palanisamy and Garg [1]. By using shorting post between the surface patch and ground plane, more miniaturization plus dual-band operation is attainable. This paper presents our computational and experimental studies of the performance of these antennas. Optimized dimensions, Feed and shorting post positions are investigated using genetic algorithm as one of the best engines for thorough searching in problems of many parameters [2]. This very compact H-shaped antenna is optimized to operate in 900 MHz and 1800 MHz for GSM application. We also proposed a flexible and accurate model of coaxial and shorting post in prob-fed microstrip antennas discussed in [3] and is useful for optimization process. The method of analysis is moment with RWG basis functions. More information is provided in [3]. A prototype was designed, fabricated and tested to be used in GSM systems. Good agreement has been obtained between theoretical and experimental results.
{"title":"Compact H-Antenna with Shorting Post for GSM Using Genetic Algorithm and Moment Method","authors":"N. Komjani, M. Ostadrahimi","doi":"10.1109/IWAT.2006.1609011","DOIUrl":"https://doi.org/10.1109/IWAT.2006.1609011","url":null,"abstract":"y increasing demand for multi-frequency services in communication, the need for compact and multi-band antennas has been growing recently. Microstrip patch antennas for their special characteristics such as low profile, light weight, conformity and ease of fabrication are widely used. They are manufactured in many different shapes and geometries. Among them, H-shaped microstrip antennas are one of compact structures which have been investigated by Palanisamy and Garg [1]. By using shorting post between the surface patch and ground plane, more miniaturization plus dual-band operation is attainable. This paper presents our computational and experimental studies of the performance of these antennas. Optimized dimensions, Feed and shorting post positions are investigated using genetic algorithm as one of the best engines for thorough searching in problems of many parameters [2]. This very compact H-shaped antenna is optimized to operate in 900 MHz and 1800 MHz for GSM application. We also proposed a flexible and accurate model of coaxial and shorting post in prob-fed microstrip antennas discussed in [3] and is useful for optimization process. The method of analysis is moment with RWG basis functions. More information is provided in [3]. A prototype was designed, fabricated and tested to be used in GSM systems. Good agreement has been obtained between theoretical and experimental results.","PeriodicalId":162557,"journal":{"name":"IEEE International Workshop on Antenna Technology Small Antennas and Novel Metamaterials, 2006.","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127512559","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}
Pub Date : 2006-03-06DOI: 10.1109/IWAT.2006.1609064
T. Zwick, Duixian Liu, J. Grzyb, B. Gaucher
A coplanar patch antenna suitable for integration with millimeter wave (mmWave) transceiver ICs is presented. The antenna is printed on a fused silica substrate and can be connected to a silicon transceiver via solder balls with 150µm pitch. The antenna was designed and manufactured for the 60GHz industrial scientific medical (ISM) band and shows about 5GHz of bandwidth with high efficiency. In the following, simulations and measurements of antenna matching, gain and radiation pattern are presented and discussed.
{"title":"A Coplanar Patch Antenna for Integration with mmWave SiGe Transceiver","authors":"T. Zwick, Duixian Liu, J. Grzyb, B. Gaucher","doi":"10.1109/IWAT.2006.1609064","DOIUrl":"https://doi.org/10.1109/IWAT.2006.1609064","url":null,"abstract":"A coplanar patch antenna suitable for integration with millimeter wave (mmWave) transceiver ICs is presented. The antenna is printed on a fused silica substrate and can be connected to a silicon transceiver via solder balls with 150µm pitch. The antenna was designed and manufactured for the 60GHz industrial scientific medical (ISM) band and shows about 5GHz of bandwidth with high efficiency. In the following, simulations and measurements of antenna matching, gain and radiation pattern are presented and discussed.","PeriodicalId":162557,"journal":{"name":"IEEE International Workshop on Antenna Technology Small Antennas and Novel Metamaterials, 2006.","volume":"138 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128611439","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}
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