Pub Date : 2000-11-06DOI: 10.1109/APWC.2000.900150
A. Healey, C. Bianchi, K. Sivaprasad
A sounding of the outdoor wideband channel at 2.4 GHz was performed directly in the frequency domain. The sounding was performed in a residential section of the University of New Hampshire campus. The distance-power gradient in this area was found to be 2.532. Large-scale fading was found to be lognormal with a standard deviation of 9 dB. Small-scale or multipath fading best fit the Weibull distribution and had a standard deviation of 5 dB. The fade slope fit a Laplacian distribution well and had a standard deviation of 4 dB/MHz.
{"title":"Wideband outdoor channel sounding at 2.4 GHz","authors":"A. Healey, C. Bianchi, K. Sivaprasad","doi":"10.1109/APWC.2000.900150","DOIUrl":"https://doi.org/10.1109/APWC.2000.900150","url":null,"abstract":"A sounding of the outdoor wideband channel at 2.4 GHz was performed directly in the frequency domain. The sounding was performed in a residential section of the University of New Hampshire campus. The distance-power gradient in this area was found to be 2.532. Large-scale fading was found to be lognormal with a standard deviation of 9 dB. Small-scale or multipath fading best fit the Weibull distribution and had a standard deviation of 5 dB. The fade slope fit a Laplacian distribution well and had a standard deviation of 4 dB/MHz.","PeriodicalId":106689,"journal":{"name":"2000 IEEE-APS Conference on Antennas and Propagation for Wireless Communications (Cat. No.00EX380)","volume":"464 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":"123054269","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.2000.900158
J. Gianvittorio, Y. Rabmat-Samii
Fractal geometries can be utilized to design miniaturized resonant loop antennas that can increase the flexibility of the design of planar phased arrays. Smaller fractal loop elements lead to a more optimal synthesis of phased arrays that can be incorporated into portable wireless devices. Their planar structures also allows for easy fabrication.
{"title":"Fractal loop elements in phased arrays for wireless communication: design, analysis, and measurement","authors":"J. Gianvittorio, Y. Rabmat-Samii","doi":"10.1109/APWC.2000.900158","DOIUrl":"https://doi.org/10.1109/APWC.2000.900158","url":null,"abstract":"Fractal geometries can be utilized to design miniaturized resonant loop antennas that can increase the flexibility of the design of planar phased arrays. Smaller fractal loop elements lead to a more optimal synthesis of phased arrays that can be incorporated into portable wireless devices. Their planar structures also allows for easy fabrication.","PeriodicalId":106689,"journal":{"name":"2000 IEEE-APS Conference on Antennas and Propagation for Wireless Communications (Cat. No.00EX380)","volume":"187 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":"121051409","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.2000.900173
P. Singhal, P. Sharma, R.D. Gupta
The design of a compact Rotman (1963) type lens for wide angle scanning has been proposed. The lens designed using the proposed approach has been analyzed using the contour integral approach. The effects of the design parameters on the radiation patterns have also been investigated.
{"title":"Effects of design parameters on the radiation pattern of Rotman type multiple beam forming lens","authors":"P. Singhal, P. Sharma, R.D. Gupta","doi":"10.1109/APWC.2000.900173","DOIUrl":"https://doi.org/10.1109/APWC.2000.900173","url":null,"abstract":"The design of a compact Rotman (1963) type lens for wide angle scanning has been proposed. The lens designed using the proposed approach has been analyzed using the contour integral approach. The effects of the design parameters on the radiation patterns have also been investigated.","PeriodicalId":106689,"journal":{"name":"2000 IEEE-APS Conference on Antennas and Propagation for Wireless Communications (Cat. No.00EX380)","volume":"23 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":"126289778","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.2000.900170
Y. Takatori, K. Cho, T. Hori
The popularity of mobile communications has pushed the demand for channel capacity ever higher. However, frequency resources are limited and most frequencies in the microwave band, which are suited to mobile communications, have already been assigned to various radio systems. Thus, frequency reuse is now one of the most important issues facing future wireless communication systems. Smart antennas have been receiving much attention with respect to this issue because base stations employing these antennas can effectively suppress co-channel interference by controlling the beam pattern and reducing the distance between the cells using the same channel. Generally, each smart antenna base station controls its beam pattern independently. However, the reduction in distance is limited when using this independent pattern control scheme. We propose a new beam-forming algorithm as a solution for actualizing the pattern control of multiple smart-antenna base stations in an actual cellular system. This paper first describes the problem that an ordinary smart antenna base station is faced with when the distance between the base stations becomes short. Then the proposed new beam-forming algorithm is described. Finally, the effectiveness of the proposed algorithm is evaluated by computer simulation.
{"title":"New beam-forming algorithm controlling pattern of multiple smart antennas for cellular systems","authors":"Y. Takatori, K. Cho, T. Hori","doi":"10.1109/APWC.2000.900170","DOIUrl":"https://doi.org/10.1109/APWC.2000.900170","url":null,"abstract":"The popularity of mobile communications has pushed the demand for channel capacity ever higher. However, frequency resources are limited and most frequencies in the microwave band, which are suited to mobile communications, have already been assigned to various radio systems. Thus, frequency reuse is now one of the most important issues facing future wireless communication systems. Smart antennas have been receiving much attention with respect to this issue because base stations employing these antennas can effectively suppress co-channel interference by controlling the beam pattern and reducing the distance between the cells using the same channel. Generally, each smart antenna base station controls its beam pattern independently. However, the reduction in distance is limited when using this independent pattern control scheme. We propose a new beam-forming algorithm as a solution for actualizing the pattern control of multiple smart-antenna base stations in an actual cellular system. This paper first describes the problem that an ordinary smart antenna base station is faced with when the distance between the base stations becomes short. Then the proposed new beam-forming algorithm is described. Finally, the effectiveness of the proposed algorithm is evaluated by computer simulation.","PeriodicalId":106689,"journal":{"name":"2000 IEEE-APS Conference on Antennas and Propagation for Wireless Communications (Cat. No.00EX380)","volume":"2 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":"128118264","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.2000.900157
J.T. MacDonald, D. Ucci
We introduce a procedure for designing an antenna system based on a single dipole element surrounded by an array of scattering elements. The goal is to achieve a desired pattern by astute placement of the elements in a fixed grid. This represents a departure from the traditional approach to directive arrays in which the current in each element is controlled. The problem is similar to the design of a reflector to achieve some arbitrary pattern. We describe the problem, propose a design approach, present simulations of the resultant system, and comment on the performance and optimality of such a system.
{"title":"Design of a passive element array","authors":"J.T. MacDonald, D. Ucci","doi":"10.1109/APWC.2000.900157","DOIUrl":"https://doi.org/10.1109/APWC.2000.900157","url":null,"abstract":"We introduce a procedure for designing an antenna system based on a single dipole element surrounded by an array of scattering elements. The goal is to achieve a desired pattern by astute placement of the elements in a fixed grid. This represents a departure from the traditional approach to directive arrays in which the current in each element is controlled. The problem is similar to the design of a reflector to achieve some arbitrary pattern. We describe the problem, propose a design approach, present simulations of the resultant system, and comment on the performance and optimality of such a system.","PeriodicalId":106689,"journal":{"name":"2000 IEEE-APS Conference on Antennas and Propagation for Wireless Communications (Cat. No.00EX380)","volume":"44 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":"134354485","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.2000.900144
E. Costamagna, L. Favalli, P. Gamba, Elisa Passi, F. Babich
Accurate models of digital transmission channels is fundamental in the assessment of the performance of communications systems. In particular generative models for their usability in simulations have been studied through the years. In this paper we describe a model using deterministic hidden Markov systems customized to match experimental data and provide some rule of thumb to drive the architectural choices of the state diagram. Model parameters are tuned by means of the Baum-Welch algorithm starting from measured error patterns in an indoor environment in the 1.9 GHz band for different receiver speeds and interference levels.
{"title":"An hidden Markov model for indoor channel based on experimental data","authors":"E. Costamagna, L. Favalli, P. Gamba, Elisa Passi, F. Babich","doi":"10.1109/APWC.2000.900144","DOIUrl":"https://doi.org/10.1109/APWC.2000.900144","url":null,"abstract":"Accurate models of digital transmission channels is fundamental in the assessment of the performance of communications systems. In particular generative models for their usability in simulations have been studied through the years. In this paper we describe a model using deterministic hidden Markov systems customized to match experimental data and provide some rule of thumb to drive the architectural choices of the state diagram. Model parameters are tuned by means of the Baum-Welch algorithm starting from measured error patterns in an indoor environment in the 1.9 GHz band for different receiver speeds and interference levels.","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":"128009697","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.2000.900135
M. Manteghi, S. S. Naeini, A. Abbaspur
The intrinsic disadvantages of patch antennas such as narrow bandwidth and nonuniform coverage are the reasons why this class of antenna has not been seriously considered for hand-held application. In this paper we present a new design for a U-shaped patch antenna that has a reasonable bandwidth, adequate coverage, and less interaction with the head and the hand of the user. Based on our earlier investigations (Manteghi 1997; and Manteghi et al. 1996) the important goals of the research reported here, were to obtain the maximum coverage and to properly correct the near-field pattern so that the undesired interactions with the user's head and hand are minimized.
贴片天线固有的缺点，如窄带宽和不均匀覆盖是这类天线没有被认真考虑用于手持应用的原因。在本文中，我们提出了一种新的u形贴片天线设计，该天线具有合理的带宽，足够的覆盖范围，并且与用户的头部和手的交互较少。基于我们早期的调查(Manteghi 1997;和Manteghi et al. 1996)，这里报告的研究的重要目标是获得最大的覆盖范围，并适当地纠正近场模式，从而最大限度地减少与用户头部和手部的不希望的交互。
{"title":"A U-shaped inverted F microstrip patch antenna for portable terminals","authors":"M. Manteghi, S. S. Naeini, A. Abbaspur","doi":"10.1109/APWC.2000.900135","DOIUrl":"https://doi.org/10.1109/APWC.2000.900135","url":null,"abstract":"The intrinsic disadvantages of patch antennas such as narrow bandwidth and nonuniform coverage are the reasons why this class of antenna has not been seriously considered for hand-held application. In this paper we present a new design for a U-shaped patch antenna that has a reasonable bandwidth, adequate coverage, and less interaction with the head and the hand of the user. Based on our earlier investigations (Manteghi 1997; and Manteghi et al. 1996) the important goals of the research reported here, were to obtain the maximum coverage and to properly correct the near-field pattern so that the undesired interactions with the user's head and hand are minimized.","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":"134367767","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.2000.900128
K. Rosengren, P. Kildal, J. Carlsson, O. Lundén
This paper considers characterization of small antennas, which operate in a multipath environment, such as antennas for mobile phones and Bluetooth modules. The characterization method is based on measurements in a reverberation chamber, which is possible due to the fact that the terminals are located in a complex multipath environment, so that normal characteristics such as radiation pattern shapes are often not important. The reverberation chamber, also called a mode-stirred chamber, is known in the EMC area, and is a kind of statistic multimode chamber. The present paper reports measurements of a simple test case in an existing reverberation chamber. The test case is a dipole located at different distances from a lossy dielectric cylinder, representing human tissue. The measurements were taken in the 900 MHz-band (870-970 MHz).
{"title":"A new method to measure radiation efficiency of terminal antennas","authors":"K. Rosengren, P. Kildal, J. Carlsson, O. Lundén","doi":"10.1109/APWC.2000.900128","DOIUrl":"https://doi.org/10.1109/APWC.2000.900128","url":null,"abstract":"This paper considers characterization of small antennas, which operate in a multipath environment, such as antennas for mobile phones and Bluetooth modules. The characterization method is based on measurements in a reverberation chamber, which is possible due to the fact that the terminals are located in a complex multipath environment, so that normal characteristics such as radiation pattern shapes are often not important. The reverberation chamber, also called a mode-stirred chamber, is known in the EMC area, and is a kind of statistic multimode chamber. The present paper reports measurements of a simple test case in an existing reverberation chamber. The test case is a dipole located at different distances from a lossy dielectric cylinder, representing human tissue. The measurements were taken in the 900 MHz-band (870-970 MHz).","PeriodicalId":106689,"journal":{"name":"2000 IEEE-APS Conference on Antennas and Propagation for Wireless Communications (Cat. No.00EX380)","volume":"103 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":"116455839","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.2000.900162
V. Braude, S.B. Sukhovetskaya, B. J. Sukhovetsky
The authors illustrate the idea of a folding horn type antenna. The main difference from a traditional horn is its multipoint excitation. In ordinary horns the increase of aperture dimensions for a given length of the horn leads to undesirable quadratic phase variations of radiating field in its aperture. To avoid them a large length of the horn is essential. In a folding horn the necessary in-phase aperture field distribution is attained by its multipoint array type excitation.
{"title":"Wide-band folding horn type microwave antennas","authors":"V. Braude, S.B. Sukhovetskaya, B. J. Sukhovetsky","doi":"10.1109/APWC.2000.900162","DOIUrl":"https://doi.org/10.1109/APWC.2000.900162","url":null,"abstract":"The authors illustrate the idea of a folding horn type antenna. The main difference from a traditional horn is its multipoint excitation. In ordinary horns the increase of aperture dimensions for a given length of the horn leads to undesirable quadratic phase variations of radiating field in its aperture. To avoid them a large length of the horn is essential. In a folding horn the necessary in-phase aperture field distribution is attained by its multipoint array type excitation.","PeriodicalId":106689,"journal":{"name":"2000 IEEE-APS Conference on Antennas and Propagation for Wireless Communications (Cat. No.00EX380)","volume":"5 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":"114671299","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.2000.900152
E. Costamagna, A. Fanni, L. Favalli, P. Gamba
Recent works introduced models based on chaos equations, aiming to simulate transmission processes over mobile radio digital channels at the level of the post detection error time series, and to reproduce their non renewal behaviors. Bursts and clusters of errors are generated by these models exploiting the correlation between successive points sampled from the trajectories of suitable strange attractors. In this paper, automatic search procedures are introduced to optimize the model parameters in order to closely comply with the statistical characteristics of target error sequences derived from DECT system simulators, and some significant results are provided.
{"title":"Experiments in modeling the parameters of chaos equation models for mobile radio channels","authors":"E. Costamagna, A. Fanni, L. Favalli, P. Gamba","doi":"10.1109/APWC.2000.900152","DOIUrl":"https://doi.org/10.1109/APWC.2000.900152","url":null,"abstract":"Recent works introduced models based on chaos equations, aiming to simulate transmission processes over mobile radio digital channels at the level of the post detection error time series, and to reproduce their non renewal behaviors. Bursts and clusters of errors are generated by these models exploiting the correlation between successive points sampled from the trajectories of suitable strange attractors. In this paper, automatic search procedures are introduced to optimize the model parameters in order to closely comply with the statistical characteristics of target error sequences derived from DECT system simulators, and some significant results are provided.","PeriodicalId":106689,"journal":{"name":"2000 IEEE-APS Conference on Antennas and Propagation for Wireless Communications (Cat. No.00EX380)","volume":"60 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":"122637408","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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