Summary form only given. A preliminary study has been performed which develops an exact, causal analytical solution to the physical optics (PO) approximation for the on-axis transient scattering from a 2-D parabolic cylinder whose concave face is illuminated by an axially incident impulsive plane wave. This analytical time-domain PO (or TD-PO) solution indicates, upon comparison with the corresponding TD-UTD (uniform theory of diffraction) solution, that the TD-UTD is noncausal for observation points beyond the focus (caustic), as expected; however, the causal part of the early TD-UTD solution compares very well analytically and provides numerical results which agree extremely well with the TD-PO solution, indicating that the causal part of the TD-UTD is not really affected by the noncausal portion of the response.<>
{"title":"On the question of time causality for HF ray fields traversing caustics","authors":"P. Pathak, R. Burkholder","doi":"10.1109/APS.1992.221617","DOIUrl":"https://doi.org/10.1109/APS.1992.221617","url":null,"abstract":"Summary form only given. A preliminary study has been performed which develops an exact, causal analytical solution to the physical optics (PO) approximation for the on-axis transient scattering from a 2-D parabolic cylinder whose concave face is illuminated by an axially incident impulsive plane wave. This analytical time-domain PO (or TD-PO) solution indicates, upon comparison with the corresponding TD-UTD (uniform theory of diffraction) solution, that the TD-UTD is noncausal for observation points beyond the focus (caustic), as expected; however, the causal part of the early TD-UTD solution compares very well analytically and provides numerical results which agree extremely well with the TD-PO solution, indicating that the causal part of the TD-UTD is not really affected by the noncausal portion of the response.<<ETX>>","PeriodicalId":289865,"journal":{"name":"IEEE Antennas and Propagation Society International Symposium 1992 Digest","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124308189","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}
The hybrid thin-slot algorithm (HTSA) integrates a transient integral-equation solution for an aperture in an infinite plane into a finite-difference time-domain (FDTD) code. A general implementation for arbitrary thin slots is described. The 3-D FDTD code TSAR was selected for the implementation. The implementation of the HTSA into TSAR is based on a slot data file that includes the cell indices where the desired slots are to exist within the FDTD mesh. For an HTSA-defined slot, the wall region local to the slot is shorted, and, therefore, to change the slot's topology simply requires altering the file to include the desired cells. Results are presented for a rectangular hatch-type aperture coupling into a rectangular cavity.<>
{"title":"Modeling arbitrarily directed slots that are narrow both in width and depth with regard to the FDTD spatial cell","authors":"D. Riley, C. Turner","doi":"10.1109/APS.1992.221535","DOIUrl":"https://doi.org/10.1109/APS.1992.221535","url":null,"abstract":"The hybrid thin-slot algorithm (HTSA) integrates a transient integral-equation solution for an aperture in an infinite plane into a finite-difference time-domain (FDTD) code. A general implementation for arbitrary thin slots is described. The 3-D FDTD code TSAR was selected for the implementation. The implementation of the HTSA into TSAR is based on a slot data file that includes the cell indices where the desired slots are to exist within the FDTD mesh. For an HTSA-defined slot, the wall region local to the slot is shorted, and, therefore, to change the slot's topology simply requires altering the file to include the desired cells. Results are presented for a rectangular hatch-type aperture coupling into a rectangular cavity.<<ETX>>","PeriodicalId":289865,"journal":{"name":"IEEE Antennas and Propagation Society International Symposium 1992 Digest","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124439589","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}
The antenna for a 3-D pulsed radar system described comprises a parabolic cylinder reflector with a linear array feed at its focus. The feed takes the form of a corrugated waveguide slow-wave structure with offset crossed-slot radiators in its broadface. A comprehensive analysis of this arrangement established that by correctly locating these X-slots relative to the center line of the slow waveguide, a circularly polarized radiated wave is obtainable in the broadside direction. The reactive surface formed by the choked groove structure provides a surface which is 'soft' to the horizontally polarized radiation emitted by the X-slot, while the exposed edges of the metallic fins behave as a soft ground plane for the vertically polarized radiated wave. In principle, if the surfaces are equally soft, the beamwidths for both radiation components would be harmonized. The fact that this is not achieved in practice can be attributed partly to the limited width of the soft surface, and to the fact that the surface is separated from the slot by a short parallel plate region. Ideally, a soft surface into which the slot is embedded is required.<>
{"title":"'Soft' surface linear array feed for a frequency scanned antenna","authors":"A. Sangster","doi":"10.1109/APS.1992.221610","DOIUrl":"https://doi.org/10.1109/APS.1992.221610","url":null,"abstract":"The antenna for a 3-D pulsed radar system described comprises a parabolic cylinder reflector with a linear array feed at its focus. The feed takes the form of a corrugated waveguide slow-wave structure with offset crossed-slot radiators in its broadface. A comprehensive analysis of this arrangement established that by correctly locating these X-slots relative to the center line of the slow waveguide, a circularly polarized radiated wave is obtainable in the broadside direction. The reactive surface formed by the choked groove structure provides a surface which is 'soft' to the horizontally polarized radiation emitted by the X-slot, while the exposed edges of the metallic fins behave as a soft ground plane for the vertically polarized radiated wave. In principle, if the surfaces are equally soft, the beamwidths for both radiation components would be harmonized. The fact that this is not achieved in practice can be attributed partly to the limited width of the soft surface, and to the fact that the surface is separated from the slot by a short parallel plate region. Ideally, a soft surface into which the slot is embedded is required.<<ETX>>","PeriodicalId":289865,"journal":{"name":"IEEE Antennas and Propagation Society International Symposium 1992 Digest","volume":"235 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124587508","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}
The authors present modeling results in frequency domain and experimental validation of superconductive transmission lines. SPICE simulations have demonstrated the advantages of using the high T/sub c/ superconductive interconnections for applications to fast logic circuits and their integration in multichip modules. Low losses of these materials allow novel devices to be studied (delay lines, devices with controlled dispersion, etc.).<>
{"title":"HT/sub c/ superconductive interconnections for ultra fast logic circuits","authors":"B. Cabon, T. Vu Dinh, J. Chilo","doi":"10.1109/APS.1992.221782","DOIUrl":"https://doi.org/10.1109/APS.1992.221782","url":null,"abstract":"The authors present modeling results in frequency domain and experimental validation of superconductive transmission lines. SPICE simulations have demonstrated the advantages of using the high T/sub c/ superconductive interconnections for applications to fast logic circuits and their integration in multichip modules. Low losses of these materials allow novel devices to be studied (delay lines, devices with controlled dispersion, etc.).<<ETX>>","PeriodicalId":289865,"journal":{"name":"IEEE Antennas and Propagation Society International Symposium 1992 Digest","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114428125","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}
A technique for obtaining low transmit sidelobes for active phased arrays that use solid-state transmit/receive modules for amplitude and phase control at each radiating element is described. The low sidelobes are obtained by a combination of limited control of module output power and statistical thinning. The advantage of the technique is that the sidelobes are controlled electronically on a digital basis and the array employs identical T/R (transmit/receive) modules, eliminating the need for different voltage levels or modules with different output power levels. This technique further allows the array to provide low or uniform sidelobes depending on the need.<>
{"title":"A technique for low transmit sidelobes in active phases arrays","authors":"A. Agrawal","doi":"10.1109/APS.1992.221906","DOIUrl":"https://doi.org/10.1109/APS.1992.221906","url":null,"abstract":"A technique for obtaining low transmit sidelobes for active phased arrays that use solid-state transmit/receive modules for amplitude and phase control at each radiating element is described. The low sidelobes are obtained by a combination of limited control of module output power and statistical thinning. The advantage of the technique is that the sidelobes are controlled electronically on a digital basis and the array employs identical T/R (transmit/receive) modules, eliminating the need for different voltage levels or modules with different output power levels. This technique further allows the array to provide low or uniform sidelobes depending on the need.<<ETX>>","PeriodicalId":289865,"journal":{"name":"IEEE Antennas and Propagation Society International Symposium 1992 Digest","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114594891","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}
The spectral domain full-wave analysis and the moment method were used to analyze coplanar parasitic subarrays. The first configuration studies was a radiating-edge-gap-coupled three-element subarray. It was found that convergence problems are encountered if entire domain cavity-mode basis functions are used. Consequently, piecewise-sinusoidal (PWS) expansion modes were used instead. The gap widths for the five cases considered were in multiples of each other, in the range of 0.0825-1.32 cm.<>
{"title":"Moment method analysis of coplanar parasitic subarrays","authors":"Wei Chen, Kai-fong Lee, R. Lee","doi":"10.1109/APS.1992.221494","DOIUrl":"https://doi.org/10.1109/APS.1992.221494","url":null,"abstract":"The spectral domain full-wave analysis and the moment method were used to analyze coplanar parasitic subarrays. The first configuration studies was a radiating-edge-gap-coupled three-element subarray. It was found that convergence problems are encountered if entire domain cavity-mode basis functions are used. Consequently, piecewise-sinusoidal (PWS) expansion modes were used instead. The gap widths for the five cases considered were in multiples of each other, in the range of 0.0825-1.32 cm.<<ETX>>","PeriodicalId":289865,"journal":{"name":"IEEE Antennas and Propagation Society International Symposium 1992 Digest","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114602297","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}
Summary form only given. The author discussed aspects of simulating practical microwave circuits with real-world constraints, such as modeling errors, process variations, layout effects, and circuit size. Simulation examples which integrate linear and nonlinear problems as well as system simulation requirements were considered. Typical circuit topologies examined were multistage monolithic power amplifiers, passive balun structures, and digital FM receivers. The application of time-domain versus frequency-domain simulation techniques was also studied. In addition, the use of EM simulators to evaluate critical circuit aspects was included.<>
{"title":"Modeling microwave circuits: linear, nonlinear and system simulation","authors":"A. Pavio","doi":"10.1109/APS.1992.221654","DOIUrl":"https://doi.org/10.1109/APS.1992.221654","url":null,"abstract":"Summary form only given. The author discussed aspects of simulating practical microwave circuits with real-world constraints, such as modeling errors, process variations, layout effects, and circuit size. Simulation examples which integrate linear and nonlinear problems as well as system simulation requirements were considered. Typical circuit topologies examined were multistage monolithic power amplifiers, passive balun structures, and digital FM receivers. The application of time-domain versus frequency-domain simulation techniques was also studied. In addition, the use of EM simulators to evaluate critical circuit aspects was included.<<ETX>>","PeriodicalId":289865,"journal":{"name":"IEEE Antennas and Propagation Society International Symposium 1992 Digest","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115012605","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}
Summary form only given. Modeling and simulation capabilities are key components ULSI design systems yet to be developed. Issues in this area revolve around the critical ability to perform efficient simulation, i.e., the simulation with the least real-time delay before acceptably accurate results are available to the design engineer in an information format. Implicit in this is the premise that there is never enough computational and information management capability to fully analyze (no approximations or truncations) real designs in times consistent with human design engineering practice. The exploration and definition of the boundaries between different electrical analysis domains were discussed. Design data manipulation and information management, which are critical for systems involving a few dozen chips with a few thousand I/Os and a few tens of thousands of interconnect lines and which will become more of an issue when the chip I/O count and interconnect line count increase by one or two orders of magnitude, were also considered.<>
{"title":"Electrical modeling and simulation issues in ULSI packaging","authors":"J. Prince","doi":"10.1109/APS.1992.221660","DOIUrl":"https://doi.org/10.1109/APS.1992.221660","url":null,"abstract":"Summary form only given. Modeling and simulation capabilities are key components ULSI design systems yet to be developed. Issues in this area revolve around the critical ability to perform efficient simulation, i.e., the simulation with the least real-time delay before acceptably accurate results are available to the design engineer in an information format. Implicit in this is the premise that there is never enough computational and information management capability to fully analyze (no approximations or truncations) real designs in times consistent with human design engineering practice. The exploration and definition of the boundaries between different electrical analysis domains were discussed. Design data manipulation and information management, which are critical for systems involving a few dozen chips with a few thousand I/Os and a few tens of thousands of interconnect lines and which will become more of an issue when the chip I/O count and interconnect line count increase by one or two orders of magnitude, were also considered.<<ETX>>","PeriodicalId":289865,"journal":{"name":"IEEE Antennas and Propagation Society International Symposium 1992 Digest","volume":"416 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117307838","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}
The authors present the development of wideband network models for practical monopoles in both free space and parallel plate structures. The models are demonstrated for practical monopole realizations in the 3-20-GHz frequency range. The synthesis technique, which utilizes precision measured data and nonlinear weighted least-squares estimation, has been shown to provide accurate network models for monopole antennas in free space and in a parallel plate structure.<>
{"title":"A technique for wideband impedance characterization of practical monopoles in free space and parallel plate structures","authors":"M. Simich, G. Branner","doi":"10.1109/APS.1992.221519","DOIUrl":"https://doi.org/10.1109/APS.1992.221519","url":null,"abstract":"The authors present the development of wideband network models for practical monopoles in both free space and parallel plate structures. The models are demonstrated for practical monopole realizations in the 3-20-GHz frequency range. The synthesis technique, which utilizes precision measured data and nonlinear weighted least-squares estimation, has been shown to provide accurate network models for monopole antennas in free space and in a parallel plate structure.<<ETX>>","PeriodicalId":289865,"journal":{"name":"IEEE Antennas and Propagation Society International Symposium 1992 Digest","volume":"98 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117351448","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}
A structure comprising a perforated screen with double connected apertures is studied using an efficient two-step procedure. The radiation of the array of patches is evaluated by a Green's function relative to the perforated screen with simply connected aperture A', embedded in a stratified dielectric support (the reference structure). Pursuing this idea, the patches P are removed by the equivalence theorem and substituted with an unknown distribution of electric current. Then, the scattering problem is solved by enforcing the vanishing of the electric field on the patches. An important point in this procedure is that the Green's function of the reference structure is determined by the aperture approach described in by R. Orta et al. (1988). Hence, the most natural approach is used for each substructure and no cascading procedure is needed. An example of results with the proposed method is given.<>
{"title":"A new class of frequency selective surfaces","authors":"R. Orta, P. Savi, R. Tascone","doi":"10.1109/APS.1992.221508","DOIUrl":"https://doi.org/10.1109/APS.1992.221508","url":null,"abstract":"A structure comprising a perforated screen with double connected apertures is studied using an efficient two-step procedure. The radiation of the array of patches is evaluated by a Green's function relative to the perforated screen with simply connected aperture A', embedded in a stratified dielectric support (the reference structure). Pursuing this idea, the patches P are removed by the equivalence theorem and substituted with an unknown distribution of electric current. Then, the scattering problem is solved by enforcing the vanishing of the electric field on the patches. An important point in this procedure is that the Green's function of the reference structure is determined by the aperture approach described in by R. Orta et al. (1988). Hence, the most natural approach is used for each substructure and no cascading procedure is needed. An example of results with the proposed method is given.<<ETX>>","PeriodicalId":289865,"journal":{"name":"IEEE Antennas and Propagation Society International Symposium 1992 Digest","volume":"91 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116164764","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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