Pub Date : 2000-11-06DOI: 10.1109/APWC.2000.900138
S. Vajha, S. N. Prasad
In this paper, the design, modeling, and experimental validation of the model of a proximity coupled or electromagnetically coupled (EMC) linearly polarized patch antenna are presented. Guidelines for developing a simple model, and design of the EMC patch antennas are outlined. This work can be used for modeling and accurate design of the proximity coupled patch antenna without resorting to time consuming experimental optimization approach. The model presented in this paper predicts the resonant frequency of the antenna accurately.
{"title":"Design and modeling of proximity coupled patch antenna","authors":"S. Vajha, S. N. Prasad","doi":"10.1109/APWC.2000.900138","DOIUrl":"https://doi.org/10.1109/APWC.2000.900138","url":null,"abstract":"In this paper, the design, modeling, and experimental validation of the model of a proximity coupled or electromagnetically coupled (EMC) linearly polarized patch antenna are presented. Guidelines for developing a simple model, and design of the EMC patch antennas are outlined. This work can be used for modeling and accurate design of the proximity coupled patch antenna without resorting to time consuming experimental optimization approach. The model presented in this paper predicts the resonant frequency of the antenna accurately.","PeriodicalId":106689,"journal":{"name":"2000 IEEE-APS Conference on Antennas and Propagation for Wireless Communications (Cat. No.00EX380)","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129821899","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 : 2000-11-06DOI: 10.1109/APWC.2000.900159
A. Zaghloul, E. C. Kohls, R.K. Gupta, L.Q. Sun
A class of flat antenna arrays that uses multi-layer printed circuit technology offers several advantages that make them attractive for mobile and wireless communications. Lower profile and lighter weight are among the desirable features. This paper surveys the applications that may use this type of antenna and reviews some of the developments for consumer terminals in a number of mobile and wireless communications systems. The first example is for a Ku-band briefcase mobile terminal in a code-division multiple access (CDMA) system in which interference due to high sidelobes can be tolerated. Two realizations of the transmit/receive antenna are discussed. The second example is for a briefcase mobile terminal at S-band for the INSAT satellite system. The third example is at Ka-band where considerable interest exists for local multimedia distribution systems (LMDS) and a number of emerging satellite systems that are planned.
{"title":"Low-cost flat antennas for mobile and wireless communications","authors":"A. Zaghloul, E. C. Kohls, R.K. Gupta, L.Q. Sun","doi":"10.1109/APWC.2000.900159","DOIUrl":"https://doi.org/10.1109/APWC.2000.900159","url":null,"abstract":"A class of flat antenna arrays that uses multi-layer printed circuit technology offers several advantages that make them attractive for mobile and wireless communications. Lower profile and lighter weight are among the desirable features. This paper surveys the applications that may use this type of antenna and reviews some of the developments for consumer terminals in a number of mobile and wireless communications systems. The first example is for a Ku-band briefcase mobile terminal in a code-division multiple access (CDMA) system in which interference due to high sidelobes can be tolerated. Two realizations of the transmit/receive antenna are discussed. The second example is for a briefcase mobile terminal at S-band for the INSAT satellite system. The third example is at Ka-band where considerable interest exists for local multimedia distribution systems (LMDS) and a number of emerging satellite systems that are planned.","PeriodicalId":106689,"journal":{"name":"2000 IEEE-APS Conference on Antennas and Propagation for Wireless Communications (Cat. No.00EX380)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127636434","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 : 2000-11-06DOI: 10.1109/APWC.2000.900168
M. Fujimoto, K. Nishikawa, T. Shibata, N. Suzuki, N. Itoh
The authors have proposed a novel algorithm for an adaptive array that is suitable for the multi-carrier transmission. It has already been confirmed that multi-carrier waves can be suppressed by the adaptive array in the multi-carrier transmission system (Fujimoto et al.). In this paper it is shown through computer simulation that not only the multipath waves but also the co-channel interference waves can be suppressed by the adaptive array.
提出了一种适用于多载波传输的自适应阵列算法。已经证实在多载波传输系统中，自适应阵列可以抑制多载波(Fujimoto et al.)。计算机仿真结果表明，自适应阵列不仅可以抑制多径波，还可以抑制同信道干扰波。
{"title":"An adaptive array for multi-carrier transmission","authors":"M. Fujimoto, K. Nishikawa, T. Shibata, N. Suzuki, N. Itoh","doi":"10.1109/APWC.2000.900168","DOIUrl":"https://doi.org/10.1109/APWC.2000.900168","url":null,"abstract":"The authors have proposed a novel algorithm for an adaptive array that is suitable for the multi-carrier transmission. It has already been confirmed that multi-carrier waves can be suppressed by the adaptive array in the multi-carrier transmission system (Fujimoto et al.). In this paper it is shown through computer simulation that not only the multipath waves but also the co-channel interference waves can be suppressed by the adaptive array.","PeriodicalId":106689,"journal":{"name":"2000 IEEE-APS Conference on Antennas and Propagation for Wireless Communications (Cat. No.00EX380)","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125604367","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 : 2000-11-06DOI: 10.1109/APWC.2000.900167
R. Mazzolin, J. Dahele
A wide range of technologies contribute to the implementation of military wireless networks ranging from antennas and propagation, digital signal processing, electrochemical, cryptographic and network system control. Although these technologies are well developed in their own right in wireline based networks, there are particular constraints in the categories of mobility, connectivity and energy that make it highly expensive and difficult to implement affordable wireless systems. The advantages of mobility in portable systems are complicated by problems that do not present themselves to the same extent in wire based networks. Network realignment in a dynamic mobile environment, problems associated with mutual interference, the widely random variations in signal strength and distortion associated with such rapidly changing propagation paths, as well as consequent vulnerability to interception and jamming all contribute complications which may be resolved through the application of sophisticated signal processing techniques and antennas. These solutions however, impose additional complexity and power requirements on portable terminals. The motivation to keep these portable units as simple and cheap as possible limits the ability to support sophisticated techniques and consequently drives the requirement to increase network complexity in order to compensate. Systems must also be rapidly deployable on mobile platforms in diverse operating environments.
{"title":"Technology challenges in adapting commercial wireless technology to military applications","authors":"R. Mazzolin, J. Dahele","doi":"10.1109/APWC.2000.900167","DOIUrl":"https://doi.org/10.1109/APWC.2000.900167","url":null,"abstract":"A wide range of technologies contribute to the implementation of military wireless networks ranging from antennas and propagation, digital signal processing, electrochemical, cryptographic and network system control. Although these technologies are well developed in their own right in wireline based networks, there are particular constraints in the categories of mobility, connectivity and energy that make it highly expensive and difficult to implement affordable wireless systems. The advantages of mobility in portable systems are complicated by problems that do not present themselves to the same extent in wire based networks. Network realignment in a dynamic mobile environment, problems associated with mutual interference, the widely random variations in signal strength and distortion associated with such rapidly changing propagation paths, as well as consequent vulnerability to interception and jamming all contribute complications which may be resolved through the application of sophisticated signal processing techniques and antennas. These solutions however, impose additional complexity and power requirements on portable terminals. The motivation to keep these portable units as simple and cheap as possible limits the ability to support sophisticated techniques and consequently drives the requirement to increase network complexity in order to compensate. Systems must also be rapidly deployable on mobile platforms in diverse operating environments.","PeriodicalId":106689,"journal":{"name":"2000 IEEE-APS Conference on Antennas and Propagation for Wireless Communications (Cat. No.00EX380)","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132992693","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 : 2000-11-06DOI: 10.1109/APWC.2000.900139
R. Waterhouse, D. Novak, A. Nirmalathas, C. Lim
The paper presents a MM-wave broadband printed antenna array with reduced back radiation. The sectoral coverage antenna consists of eight ASP elements to give broadband impedance and radiation performance as well as eight reflector elements to improve the front-to-back ratio. The reflector elements can be readily designed despite the limited materials available at MM-wave frequencies due to the many degrees of freedom apparent in these elements. The new array had a measured front-to-back ratio of greater than 30 dB across the entire Ka-band. As a result of the broadband nature of this antenna, it can be incorporated into a multitude of MM-wave radio services.
{"title":"Broadband printed antennas with reflector elements for millimeter-wave wireless applications","authors":"R. Waterhouse, D. Novak, A. Nirmalathas, C. Lim","doi":"10.1109/APWC.2000.900139","DOIUrl":"https://doi.org/10.1109/APWC.2000.900139","url":null,"abstract":"The paper presents a MM-wave broadband printed antenna array with reduced back radiation. The sectoral coverage antenna consists of eight ASP elements to give broadband impedance and radiation performance as well as eight reflector elements to improve the front-to-back ratio. The reflector elements can be readily designed despite the limited materials available at MM-wave frequencies due to the many degrees of freedom apparent in these elements. The new array had a measured front-to-back ratio of greater than 30 dB across the entire Ka-band. As a result of the broadband nature of this antenna, it can be incorporated into a multitude of MM-wave radio services.","PeriodicalId":106689,"journal":{"name":"2000 IEEE-APS Conference on Antennas and Propagation for Wireless Communications (Cat. No.00EX380)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122250932","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 : 2000-11-06DOI: 10.1109/APWC.2000.900146
D. Davis, B. Segal, C. Trueman, R. Calzadilla, T. Pavlasek
The fields at 850 MHz and 1.9 GHz were measured in five hospital corridors. The field strength tended to decline with distance at a free-space rate within about 2 m of the source, but at a slower rate when further away. Fields at 1.9 GHz declined more slowly than 850-MHz fields. The implications for hospital EMC management are discussed.
{"title":"Measurement of indoor propagation at 850 MHz and 1.9 GHz in hospital corridors","authors":"D. Davis, B. Segal, C. Trueman, R. Calzadilla, T. Pavlasek","doi":"10.1109/APWC.2000.900146","DOIUrl":"https://doi.org/10.1109/APWC.2000.900146","url":null,"abstract":"The fields at 850 MHz and 1.9 GHz were measured in five hospital corridors. The field strength tended to decline with distance at a free-space rate within about 2 m of the source, but at a slower rate when further away. Fields at 1.9 GHz declined more slowly than 850-MHz fields. The implications for hospital EMC management are discussed.","PeriodicalId":106689,"journal":{"name":"2000 IEEE-APS Conference on Antennas and Propagation for Wireless Communications (Cat. No.00EX380)","volume":"465 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125826552","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 : 2000-11-06DOI: 10.1109/APWC.2000.900130
J. George
A novel approach for the fast modelling of centre fed bow-tie microstrip antennas, using the modified locally conformal finite difference method (MCFDTD) coupled with the concept of symmetry plane, is presented. The use of MCFDTD enables us to choose number of cells along the antenna length and width independent of the antenna central width and the concept of symmetry plane reduces the problem space size to exactly half the otherwise required size. The suitability and accuracy of the method is demonstrated through comparison with experimental results.
{"title":"A novel approach for the modelling of bow-tie microstrip antennas using FDTD method","authors":"J. George","doi":"10.1109/APWC.2000.900130","DOIUrl":"https://doi.org/10.1109/APWC.2000.900130","url":null,"abstract":"A novel approach for the fast modelling of centre fed bow-tie microstrip antennas, using the modified locally conformal finite difference method (MCFDTD) coupled with the concept of symmetry plane, is presented. The use of MCFDTD enables us to choose number of cells along the antenna length and width independent of the antenna central width and the concept of symmetry plane reduces the problem space size to exactly half the otherwise required size. The suitability and accuracy of the method is demonstrated through comparison with experimental results.","PeriodicalId":106689,"journal":{"name":"2000 IEEE-APS Conference on Antennas and Propagation for Wireless Communications (Cat. No.00EX380)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115002538","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 : 2000-11-06DOI: 10.1109/APWC.2000.900136
A. Shackelford, Kai-fong Lee, D. Chatterjee
The coaxially-fed U-slot rectangular patch antenna and the L-probe fed rectangular patch antenna are two recently developed single-layer single-patch wideband microstrip patch antennas. In both cases, a second resonance is introduced near the main patch resonance, either by the U-slot or by the L-probe. The U-slot or the L-probe also introduce a capacitance which counteracts the inductance of the coaxial feed, allowing for the use of thick substrates (0.08-0.1 /spl Lambda//sub 0/) where /spl Lambda//sub 0/ is the free space wavelength. Using foam substrates (with /spl epsiv//sub r//spl ap/1) the impedance bandwidths of these antennas operating in the fundamental mode are in the 30-40% range, with stable pattern and gain characteristics. These bandwidths are more than sufficient for most wireless communication applications. The resonant length of the fundamental mode is about half of the free space wavelength. For many applications, it is desirable to reduce the size of the patch to conserve real estate space. For this reason, there have been extensive investigations on patch size reduction techniques. One method uses microwave substrates with values of /spl epsiv//sub r/>1. Another method uses a shorting wall at the location of zero electric field so that the resonant length is halved, resulting in the quarter-wave patch. Yet another method uses a shorting pin near the feed. This introduces capacitive coupling to the patch resonance, thereby increasing the effective /spl epsiv//sub r/, and reducing the frequency, which means that, for a given resonant frequency, the patch size becomes smaller. In this paper, results of some of these investigations are presented.
{"title":"On reducing the patch size of U-slot and L-probe wideband patch antennas","authors":"A. Shackelford, Kai-fong Lee, D. Chatterjee","doi":"10.1109/APWC.2000.900136","DOIUrl":"https://doi.org/10.1109/APWC.2000.900136","url":null,"abstract":"The coaxially-fed U-slot rectangular patch antenna and the L-probe fed rectangular patch antenna are two recently developed single-layer single-patch wideband microstrip patch antennas. In both cases, a second resonance is introduced near the main patch resonance, either by the U-slot or by the L-probe. The U-slot or the L-probe also introduce a capacitance which counteracts the inductance of the coaxial feed, allowing for the use of thick substrates (0.08-0.1 /spl Lambda//sub 0/) where /spl Lambda//sub 0/ is the free space wavelength. Using foam substrates (with /spl epsiv//sub r//spl ap/1) the impedance bandwidths of these antennas operating in the fundamental mode are in the 30-40% range, with stable pattern and gain characteristics. These bandwidths are more than sufficient for most wireless communication applications. The resonant length of the fundamental mode is about half of the free space wavelength. For many applications, it is desirable to reduce the size of the patch to conserve real estate space. For this reason, there have been extensive investigations on patch size reduction techniques. One method uses microwave substrates with values of /spl epsiv//sub r/>1. Another method uses a shorting wall at the location of zero electric field so that the resonant length is halved, resulting in the quarter-wave patch. Yet another method uses a shorting pin near the feed. This introduces capacitive coupling to the patch resonance, thereby increasing the effective /spl epsiv//sub r/, and reducing the frequency, which means that, for a given resonant frequency, the patch size becomes smaller. In this paper, results of some of these investigations are presented.","PeriodicalId":106689,"journal":{"name":"2000 IEEE-APS Conference on Antennas and Propagation for Wireless Communications (Cat. No.00EX380)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123954306","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 : 2000-11-06DOI: 10.1109/APWC.2000.900166
E. Balboni, J. Ford, R. Tingley, K. Toomey, J. Vytal
Most existing studies of indoor radio wave propagation have addressed operations in common commercial environments such as warehouses, office buildings and factories. These studies show typical path loss gradients ranging from 3-5, and rms delay spreads ranging from 10-40 nanoseconds. This paper reports the results of research conducted to characterize microwave radio propagation aboard Navy ships. Because of its principally steel construction, the ship environment displays significantly different characteristics from commercial environments. In particular, rms delay spreads ranging between 70 and 90 nanoseconds are common. Likewise, path loss gradients are observed to range from slightly greater than inverse square to smaller than unity. These effects of path loss and delay spread are found to be independent of frequency, over the range from 800 MHz to 2.6 GHz.
{"title":"An empirical study of radio propagation aboard naval vessels","authors":"E. Balboni, J. Ford, R. Tingley, K. Toomey, J. Vytal","doi":"10.1109/APWC.2000.900166","DOIUrl":"https://doi.org/10.1109/APWC.2000.900166","url":null,"abstract":"Most existing studies of indoor radio wave propagation have addressed operations in common commercial environments such as warehouses, office buildings and factories. These studies show typical path loss gradients ranging from 3-5, and rms delay spreads ranging from 10-40 nanoseconds. This paper reports the results of research conducted to characterize microwave radio propagation aboard Navy ships. Because of its principally steel construction, the ship environment displays significantly different characteristics from commercial environments. In particular, rms delay spreads ranging between 70 and 90 nanoseconds are common. Likewise, path loss gradients are observed to range from slightly greater than inverse square to smaller than unity. These effects of path loss and delay spread are found to be independent of frequency, over the range from 800 MHz to 2.6 GHz.","PeriodicalId":106689,"journal":{"name":"2000 IEEE-APS Conference on Antennas and Propagation for Wireless Communications (Cat. No.00EX380)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129096558","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 : 2000-11-06DOI: 10.1109/APWC.2000.900164
B. Svensson
Slot antennas have been widely used for military and defense applications for decades. This antenna type offers a compact and attractive solution in many cases. The use of the waveguide technique gives a low loss design and will often result in a well defined performance. Slot models and design tools are mature and present an opportunity to do most of the design work theoretically without tedious measurements and experimental efforts. The development and refinement of models for all kinds of slots has been going on since the 1940s and the literature still contains many examples of applications for slotted waveguide arrays. The slotted waveguide antenna is therefore an attractive alternative also for commercial applications. This is especially true for high frequency applications such as radio links where several frequency bands are allocated. Radar antennas and point-point antennas are mentioned in particular and radiation patterns discussed.
{"title":"Dual use of slotted waveguide array antennas","authors":"B. Svensson","doi":"10.1109/APWC.2000.900164","DOIUrl":"https://doi.org/10.1109/APWC.2000.900164","url":null,"abstract":"Slot antennas have been widely used for military and defense applications for decades. This antenna type offers a compact and attractive solution in many cases. The use of the waveguide technique gives a low loss design and will often result in a well defined performance. Slot models and design tools are mature and present an opportunity to do most of the design work theoretically without tedious measurements and experimental efforts. The development and refinement of models for all kinds of slots has been going on since the 1940s and the literature still contains many examples of applications for slotted waveguide arrays. The slotted waveguide antenna is therefore an attractive alternative also for commercial applications. This is especially true for high frequency applications such as radio links where several frequency bands are allocated. Radar antennas and point-point antennas are mentioned in particular and radiation patterns discussed.","PeriodicalId":106689,"journal":{"name":"2000 IEEE-APS Conference on Antennas and Propagation for Wireless Communications (Cat. No.00EX380)","volume":"84 5","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133020948","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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