It has been observed that it is possible to represent the solution to certain interior scattering problems, such as simple cavities, in terms of solutions to the exterior problem and the pseudo inverse of the plane wave transform (PWT) operator. This may provide a pathway to sparse direct representations for interior problems provided that sparse representations of the exterior solution operator and the pseudo inverse of the PWT are available. This paper considers the latter possibility. The approach used consists of first compressing the PWT via spatially localized current modes that radiate far fields only to specific angular regions. It is shown that the resulting operator has a sparse QR factorization, which permits the efficient direct implementation of the desired pseudo inverse operation
{"title":"Sparse Pseudo Inverse of the Discrete Plane Wave Transform","authors":"R. Adams, G. Wang, F. Canning","doi":"10.1109/TAP.2007.915420","DOIUrl":"https://doi.org/10.1109/TAP.2007.915420","url":null,"abstract":"It has been observed that it is possible to represent the solution to certain interior scattering problems, such as simple cavities, in terms of solutions to the exterior problem and the pseudo inverse of the plane wave transform (PWT) operator. This may provide a pathway to sparse direct representations for interior problems provided that sparse representations of the exterior solution operator and the pseudo inverse of the PWT are available. This paper considers the latter possibility. The approach used consists of first compressing the PWT via spatially localized current modes that radiate far fields only to specific angular regions. It is shown that the resulting operator has a sparse QR factorization, which permits the efficient direct implementation of the desired pseudo inverse operation","PeriodicalId":6423,"journal":{"name":"2006 IEEE Antennas and Propagation Society International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87408638","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 : 2008-01-09DOI: 10.1109/aps.2006.1711306
R. Mueller, R. Lorch, W. Menzel
The presented results show that the simulation with a modern simulation tool using methods of moments agree very well with the measurements of a prototype. Furthermore it is shown that the monostatic RCS of a UHF DF antenna can be successfully reduced without degrading the DF performance
{"title":"A UHF Direction Finding Antenna with Optimised Radar Cross Section","authors":"R. Mueller, R. Lorch, W. Menzel","doi":"10.1109/aps.2006.1711306","DOIUrl":"https://doi.org/10.1109/aps.2006.1711306","url":null,"abstract":"The presented results show that the simulation with a modern simulation tool using methods of moments agree very well with the measurements of a prototype. Furthermore it is shown that the monostatic RCS of a UHF DF antenna can be successfully reduced without degrading the DF performance","PeriodicalId":6423,"journal":{"name":"2006 IEEE Antennas and Propagation Society International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75725164","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 : 2006-11-01DOI: 10.1109/EUCAP.2006.4584590
C. Dominguez-Grano-De-Oro, J. Masa-Campos, M. Sierra-Pérez
An antenna for a signal identification system at 1 GHz band has been designed. The structure is based on a multi-layer configuration with patches coupled through slots by a feeding microstrip line. The system requires reduced dimensions so slots form has been designed to fit the structure. Low-cost materials have been used. Results are presented at the end of this paper
{"title":"Monopulse scanning beam planar array for signal identification system","authors":"C. Dominguez-Grano-De-Oro, J. Masa-Campos, M. Sierra-Pérez","doi":"10.1109/EUCAP.2006.4584590","DOIUrl":"https://doi.org/10.1109/EUCAP.2006.4584590","url":null,"abstract":"An antenna for a signal identification system at 1 GHz band has been designed. The structure is based on a multi-layer configuration with patches coupled through slots by a feeding microstrip line. The system requires reduced dimensions so slots form has been designed to fit the structure. Low-cost materials have been used. Results are presented at the end of this paper","PeriodicalId":6423,"journal":{"name":"2006 IEEE Antennas and Propagation Society International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2006-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80307698","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 : 2006-11-01DOI: 10.1109/EUCAP.2006.4584565
F. Vico, M. Ferrando, A. Valero, E. Alfonso
A new fast physical optics method is introduced for computing backscattered fields at high frequencies. A stokes-type method is presented for computing highly oscillatory integrals a over simplex from extremal points and the stationary phase points of the simplex. The computational cost of the scattering integral behaves as O(1) with frequency
{"title":"A new 2D fast physical optics method","authors":"F. Vico, M. Ferrando, A. Valero, E. Alfonso","doi":"10.1109/EUCAP.2006.4584565","DOIUrl":"https://doi.org/10.1109/EUCAP.2006.4584565","url":null,"abstract":"A new fast physical optics method is introduced for computing backscattered fields at high frequencies. A stokes-type method is presented for computing highly oscillatory integrals a over simplex from extremal points and the stationary phase points of the simplex. The computational cost of the scattering integral behaves as O(1) with frequency","PeriodicalId":6423,"journal":{"name":"2006 IEEE Antennas and Propagation Society International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2006-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80016841","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 : 2006-10-23DOI: 10.1109/APS.2006.1710817
M. Rankin, A. O'Brien, I. Gupta
In this paper, the effects of sampling rate on the performance of the space-time adaptive processing (STAP)-based RFI suppression system is studied when the performance metric consists of pre-correlator performance (output SNR) as well as the post-correlator performance (peak-to-peak ratio and distortion of the cross-correlation function). It is shown that for good performance, the sampling rate should be selected below or equal to the system bandwidth (front end of the antenna electronics). In general, the sampling rate is greater than the system bandwidth which leads to performance degradation. For these situations, a resampling procedure is presented which can be used effectively to reduce the sampling rate to below or equal to the system bandwidth. It is shown that when the resampled data is used in STAP, one obtains good performance. The resampling procedure consists of two steps. First, a low-pass filter is applied to the data. The bandwidth of the low-pass filter is selected to be between the desired signal bandwidth and the system bandwidth. Next, the signals are resampled to match the low-pass filter bandwidth. The antenna array and the signal scenario used in the study is described next
{"title":"Effects of Sampling Rate on STAP-Based RFI Suppression Systems","authors":"M. Rankin, A. O'Brien, I. Gupta","doi":"10.1109/APS.2006.1710817","DOIUrl":"https://doi.org/10.1109/APS.2006.1710817","url":null,"abstract":"In this paper, the effects of sampling rate on the performance of the space-time adaptive processing (STAP)-based RFI suppression system is studied when the performance metric consists of pre-correlator performance (output SNR) as well as the post-correlator performance (peak-to-peak ratio and distortion of the cross-correlation function). It is shown that for good performance, the sampling rate should be selected below or equal to the system bandwidth (front end of the antenna electronics). In general, the sampling rate is greater than the system bandwidth which leads to performance degradation. For these situations, a resampling procedure is presented which can be used effectively to reduce the sampling rate to below or equal to the system bandwidth. It is shown that when the resampled data is used in STAP, one obtains good performance. The resampling procedure consists of two steps. First, a low-pass filter is applied to the data. The bandwidth of the low-pass filter is selected to be between the desired signal bandwidth and the system bandwidth. Next, the signals are resampled to match the low-pass filter bandwidth. The antenna array and the signal scenario used in the study is described next","PeriodicalId":6423,"journal":{"name":"2006 IEEE Antennas and Propagation Society International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2006-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77648121","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 : 2006-10-23DOI: 10.1109/APS.2006.1711536
M. Antoniades, G. Eleftheriades
The recent implementation of negative-refractive-index (NRI) media by periodically loading host transmission-lines (TL) with lumped-element series capacitors and shunt inductors has led to the development of numerous practical devices based on NRI-TL metamaterials (MTM). The MTM feed networks were shown to be useful in series-fed linear arrays for effectively replacing one-wavelength long conventional meandered transmission lines, thus achieving compact, broadside radiators, whose beam squints less with frequency. In addition, the MTM feed networks can be used to create linear arrays whose main beam remains virtually fixed at a negative angle from broadside as the frequency is varied. Alternatively, a single CPS MTM feedline operating inside the radiation cone can be used to implement a leaky-wave antenna (LWA), which can be recognized as the dual of the CPW line to create a backward LWA
{"title":"A Metamaterial Series-Fed Linear Dipole Array with Reduced Beam Squinting","authors":"M. Antoniades, G. Eleftheriades","doi":"10.1109/APS.2006.1711536","DOIUrl":"https://doi.org/10.1109/APS.2006.1711536","url":null,"abstract":"The recent implementation of negative-refractive-index (NRI) media by periodically loading host transmission-lines (TL) with lumped-element series capacitors and shunt inductors has led to the development of numerous practical devices based on NRI-TL metamaterials (MTM). The MTM feed networks were shown to be useful in series-fed linear arrays for effectively replacing one-wavelength long conventional meandered transmission lines, thus achieving compact, broadside radiators, whose beam squints less with frequency. In addition, the MTM feed networks can be used to create linear arrays whose main beam remains virtually fixed at a negative angle from broadside as the frequency is varied. Alternatively, a single CPS MTM feedline operating inside the radiation cone can be used to implement a leaky-wave antenna (LWA), which can be recognized as the dual of the CPW line to create a backward LWA","PeriodicalId":6423,"journal":{"name":"2006 IEEE Antennas and Propagation Society International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2006-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88210441","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 : 2006-10-23DOI: 10.1109/APS.2006.1710857
Hong-xing Zheng
In this paper, a generalized scheme for nonorthogonal grids is introduced to the ADI-FDTD method. To reduce the complexity, the localized nonorthogonal grids are applied to anomalistic regions only, and standard FDTD grids are used for other computational regions. The conversion from the nonorthogonal grid to the Cartesian grid is done by using the Jacobi transform. It should be mentioned that in the new scheme, the second-order Mur's absorbing boundary condition (ABC) can be used with the standard FDTD, which greatly simplifies the problem
{"title":"3-D nonorthogonal ADI-FDTD algorithm for the full-wave analysis of microstrip structure","authors":"Hong-xing Zheng","doi":"10.1109/APS.2006.1710857","DOIUrl":"https://doi.org/10.1109/APS.2006.1710857","url":null,"abstract":"In this paper, a generalized scheme for nonorthogonal grids is introduced to the ADI-FDTD method. To reduce the complexity, the localized nonorthogonal grids are applied to anomalistic regions only, and standard FDTD grids are used for other computational regions. The conversion from the nonorthogonal grid to the Cartesian grid is done by using the Jacobi transform. It should be mentioned that in the new scheme, the second-order Mur's absorbing boundary condition (ABC) can be used with the standard FDTD, which greatly simplifies the problem","PeriodicalId":6423,"journal":{"name":"2006 IEEE Antennas and Propagation Society International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2006-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87855961","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 : 2006-10-23DOI: 10.1109/APS.2006.1711586
J. Ginn, B. Lail, G. Boreman
A simple sub-millimeter infrared reflectarray (SMIR) has been successfully fabricated and tested at 10.6 mum. The SMIR is comprised of three independent arrays or "stripes" of a single size element on a coated optical flat. Actual reflectarray elements consist of variable size patches which exhibit higher operating bandwidths than reflectarrays utilizing other types of elements and are easier to fabricate at small dimensions. Measured results demonstrate the feasibility of an infrared reflectarray. Continued research will focus on developing SMIR technology for use as a planar focusing element
{"title":"Infrared Patch Reflectarray","authors":"J. Ginn, B. Lail, G. Boreman","doi":"10.1109/APS.2006.1711586","DOIUrl":"https://doi.org/10.1109/APS.2006.1711586","url":null,"abstract":"A simple sub-millimeter infrared reflectarray (SMIR) has been successfully fabricated and tested at 10.6 mum. The SMIR is comprised of three independent arrays or \"stripes\" of a single size element on a coated optical flat. Actual reflectarray elements consist of variable size patches which exhibit higher operating bandwidths than reflectarrays utilizing other types of elements and are easier to fabricate at small dimensions. Measured results demonstrate the feasibility of an infrared reflectarray. Continued research will focus on developing SMIR technology for use as a planar focusing element","PeriodicalId":6423,"journal":{"name":"2006 IEEE Antennas and Propagation Society International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2006-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90643330","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 : 2006-10-23DOI: 10.1109/APS.2006.1710740
J. Yaezawa, H. Arai
In this paper, we propose the calibration technique using reference signal from known sources for two-dimensional DOA estimation, examining the array shapes and the selection of the incident angle for reference signal. We use dipole array on a finite sized ground plane to evaluate DOA estimation error in the calibration
{"title":"Calibration technique in two-dimensional DOA estimation using two linear arrays","authors":"J. Yaezawa, H. Arai","doi":"10.1109/APS.2006.1710740","DOIUrl":"https://doi.org/10.1109/APS.2006.1710740","url":null,"abstract":"In this paper, we propose the calibration technique using reference signal from known sources for two-dimensional DOA estimation, examining the array shapes and the selection of the incident angle for reference signal. We use dipole array on a finite sized ground plane to evaluate DOA estimation error in the calibration","PeriodicalId":6423,"journal":{"name":"2006 IEEE Antennas and Propagation Society International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2006-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84345432","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 : 2006-10-23DOI: 10.1109/APS.2006.1711287
D. Faircloth, S. Wentworth, M. Baginski, S. Rao
In this paper, a method was presented for accurately determining the complex CP of a material sample using a single SCL waveguide measurement. An analytic expression for the complex reflection coefficient at the reference plane of the waveguide serves as the forward problem in the novel MPSQP algorithm. The MPSQP is a very robust optimization technique which exploits the speed and accuracy of SQP while avoiding local minima trapping. This technique proves beneficial for several application areas including high temperature material characterization. At high temperatures, a considerable amount of time is devoted to changing terminations, and this process usually requires some amount of cooling and reheating of the sample. During this time, the sample may shift inside the waveguide which, in turn, may introduce errors into the measured data
{"title":"A novel constitutive parameter extraction technique using a single short circuit waveguide measurement","authors":"D. Faircloth, S. Wentworth, M. Baginski, S. Rao","doi":"10.1109/APS.2006.1711287","DOIUrl":"https://doi.org/10.1109/APS.2006.1711287","url":null,"abstract":"In this paper, a method was presented for accurately determining the complex CP of a material sample using a single SCL waveguide measurement. An analytic expression for the complex reflection coefficient at the reference plane of the waveguide serves as the forward problem in the novel MPSQP algorithm. The MPSQP is a very robust optimization technique which exploits the speed and accuracy of SQP while avoiding local minima trapping. This technique proves beneficial for several application areas including high temperature material characterization. At high temperatures, a considerable amount of time is devoted to changing terminations, and this process usually requires some amount of cooling and reheating of the sample. During this time, the sample may shift inside the waveguide which, in turn, may introduce errors into the measured data","PeriodicalId":6423,"journal":{"name":"2006 IEEE Antennas and Propagation Society International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2006-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83811109","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：