Pub Date : 2007-06-09DOI: 10.1109/APS.2007.4396173
R. Speciale
Quite recently, a number of multi-beam klystrons (MBK) have been developed experimentally, and at least three different MBK models are already commercially available. Multi-beam klystrons operate at reduced electron-gun voltage, and higher total beam-current than the single-beam designs, thus preventing occasional destructive gun- diode discharges, and increasing the power-efficiency up to ~ 75%. The power-efficiency (measured as the ratio of output microwave power to input DC power) is however still limited, even in MBK, as it is obviously impossible to extract all the microwave energy from a sharply-bunched electron-beam, without having the high space-charge-density of the slowing beam force it into uncontrollable defocusing.
{"title":"Exact expressions of the orbit-curvature and curvature-radius of the Toroidal/Helical orbits.","authors":"R. Speciale","doi":"10.1109/APS.2007.4396173","DOIUrl":"https://doi.org/10.1109/APS.2007.4396173","url":null,"abstract":"Quite recently, a number of multi-beam klystrons (MBK) have been developed experimentally, and at least three different MBK models are already commercially available. Multi-beam klystrons operate at reduced electron-gun voltage, and higher total beam-current than the single-beam designs, thus preventing occasional destructive gun- diode discharges, and increasing the power-efficiency up to ~ 75%. The power-efficiency (measured as the ratio of output microwave power to input DC power) is however still limited, even in MBK, as it is obviously impossible to extract all the microwave energy from a sharply-bunched electron-beam, without having the high space-charge-density of the slowing beam force it into uncontrollable defocusing.","PeriodicalId":117975,"journal":{"name":"2007 IEEE Antennas and Propagation Society International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122726850","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 : 2007-06-09DOI: 10.1109/APS.2007.4396926
W. Hong, W. H. Jung, Y. Yamada, N. Michishita
A 0.035 wavelength very small normal mode helical antenna is designed to achieve high antenna efficiency. Antenna gain of -3.72dBd is achieved. When this antenna is attached on a metal plate, antenna gain is increased to -0.4dBd. Communication distances of current RFID tags and NMHA tags are measured. In the case of NMHA tags, communication distances comparable to current RFID tags are ensured.
{"title":"High performance normal mode helical antennas for RFID tags","authors":"W. Hong, W. H. Jung, Y. Yamada, N. Michishita","doi":"10.1109/APS.2007.4396926","DOIUrl":"https://doi.org/10.1109/APS.2007.4396926","url":null,"abstract":"A 0.035 wavelength very small normal mode helical antenna is designed to achieve high antenna efficiency. Antenna gain of -3.72dBd is achieved. When this antenna is attached on a metal plate, antenna gain is increased to -0.4dBd. Communication distances of current RFID tags and NMHA tags are measured. In the case of NMHA tags, communication distances comparable to current RFID tags are ensured.","PeriodicalId":117975,"journal":{"name":"2007 IEEE Antennas and Propagation Society International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122743412","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 : 2007-06-09DOI: 10.1109/APS.2007.4395521
J. Martinez-Lorenzo, C. Rappaport, A. Pino
A new diagnosis method for reflector antennas using nearfield data have been presented. The application of the method for the surface profile reconstruction of a reflector antenna distorted by discrete bumps has been applied successfully.
{"title":"Reflector antenna diagnosis using nearfield data","authors":"J. Martinez-Lorenzo, C. Rappaport, A. Pino","doi":"10.1109/APS.2007.4395521","DOIUrl":"https://doi.org/10.1109/APS.2007.4395521","url":null,"abstract":"A new diagnosis method for reflector antennas using nearfield data have been presented. The application of the method for the surface profile reconstruction of a reflector antenna distorted by discrete bumps has been applied successfully.","PeriodicalId":117975,"journal":{"name":"2007 IEEE Antennas and Propagation Society International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122778726","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 : 2007-06-09DOI: 10.1109/APS.2007.4396478
D. Busuioc, G. Shaker, M. Shahabadi, S. Safavi-Naeini
{"title":"Substrate integrated waveguide radial power divider for Ka-band satellite applications","authors":"D. Busuioc, G. Shaker, M. Shahabadi, S. Safavi-Naeini","doi":"10.1109/APS.2007.4396478","DOIUrl":"https://doi.org/10.1109/APS.2007.4396478","url":null,"abstract":"","PeriodicalId":117975,"journal":{"name":"2007 IEEE Antennas and Propagation Society International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122455938","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 : 2007-06-09DOI: 10.1109/APS.2007.4396543
C. Di Nallo, G. Bit‐Babik, A. Faraone
This paper proposes a different approach to non-Foster or active matching. An antenna structure with two ports is considered. One port is used to couple the signal, while the other one is connected to a non-Foster network. The advantage of this configuration is that the antenna can be designed to have real input impedance, as seen from the feeding port, fairly constant across a very broad band when the active load is applied. The input reactance compensation is essentially performed by the non-Foster network, typically behaving as a negative inductor.
{"title":"Wideband antenna using non-foster loading elements","authors":"C. Di Nallo, G. Bit‐Babik, A. Faraone","doi":"10.1109/APS.2007.4396543","DOIUrl":"https://doi.org/10.1109/APS.2007.4396543","url":null,"abstract":"This paper proposes a different approach to non-Foster or active matching. An antenna structure with two ports is considered. One port is used to couple the signal, while the other one is connected to a non-Foster network. The advantage of this configuration is that the antenna can be designed to have real input impedance, as seen from the feeding port, fairly constant across a very broad band when the active load is applied. The input reactance compensation is essentially performed by the non-Foster network, typically behaving as a negative inductor.","PeriodicalId":117975,"journal":{"name":"2007 IEEE Antennas and Propagation Society International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122456092","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 : 2007-06-09DOI: 10.1109/APS.2007.4396895
Tzung-I Lee, Y.E. Wang
This paper focuses on a mode-based approach that can obtain the maximum gain from closely coupled antennas. Because of the small separation between the coupled dipole antennas, the antenna gain can potentially surpass the physical aperture limit and thus be called supergain. Traditional supergain antennas are actually superdirective only as the directivity can not be translated into real antenna gain because of severe impedance mismatching in those systems.
{"title":"A mode-based supergain approach with closely coupled monopole pair","authors":"Tzung-I Lee, Y.E. Wang","doi":"10.1109/APS.2007.4396895","DOIUrl":"https://doi.org/10.1109/APS.2007.4396895","url":null,"abstract":"This paper focuses on a mode-based approach that can obtain the maximum gain from closely coupled antennas. Because of the small separation between the coupled dipole antennas, the antenna gain can potentially surpass the physical aperture limit and thus be called supergain. Traditional supergain antennas are actually superdirective only as the directivity can not be translated into real antenna gain because of severe impedance mismatching in those systems.","PeriodicalId":117975,"journal":{"name":"2007 IEEE Antennas and Propagation Society International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122457854","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 : 2007-06-09DOI: 10.1109/APS.2007.4396510
A. Babakhani, D. Rutledge, A. Hajimiri
This work demonstrates W-band integrated dipole antennas and a four channel phased transceiver implemented in IBM 130 nm silicon germanium BiCMOS process. The chip includes the complete receiver, transmitter, signal generation blocks, phase shifters, and on-chip dipole antennas. A hemispherical silicon lens with diameter of about one inch is also used to remove the substrate modes. Measurement results show a maximum antenna gain of about +8 dB.
{"title":"mm-wave phased arrays in silicon with integrated antennas","authors":"A. Babakhani, D. Rutledge, A. Hajimiri","doi":"10.1109/APS.2007.4396510","DOIUrl":"https://doi.org/10.1109/APS.2007.4396510","url":null,"abstract":"This work demonstrates W-band integrated dipole antennas and a four channel phased transceiver implemented in IBM 130 nm silicon germanium BiCMOS process. The chip includes the complete receiver, transmitter, signal generation blocks, phase shifters, and on-chip dipole antennas. A hemispherical silicon lens with diameter of about one inch is also used to remove the substrate modes. Measurement results show a maximum antenna gain of about +8 dB.","PeriodicalId":117975,"journal":{"name":"2007 IEEE Antennas and Propagation Society International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122607337","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 : 2007-06-09DOI: 10.1109/APS.2007.4395919
F. Aryanfar, F.B. Turney, L. Malek, N. Buris
Toward the goal of achieving robust ray tracing based channel models this paper compares simulation results using a 3D ray-tracing tool [F. Aryanfar and S. Safavi-Naeini, 1998] vs. field measurements in different environments. The tool has been validated for many outdoor and indoor scenes at different frequency bands and is capable of accurate prediction of wireless channel parameters. To test model robustness, we also examine the sensitivity of the predicted results on inputs such as angular resolution, material properties and detail of geometry.
{"title":"A sensitivity study of ray-tracing based wireless channel simulators using field measurements","authors":"F. Aryanfar, F.B. Turney, L. Malek, N. Buris","doi":"10.1109/APS.2007.4395919","DOIUrl":"https://doi.org/10.1109/APS.2007.4395919","url":null,"abstract":"Toward the goal of achieving robust ray tracing based channel models this paper compares simulation results using a 3D ray-tracing tool [F. Aryanfar and S. Safavi-Naeini, 1998] vs. field measurements in different environments. The tool has been validated for many outdoor and indoor scenes at different frequency bands and is capable of accurate prediction of wireless channel parameters. To test model robustness, we also examine the sensitivity of the predicted results on inputs such as angular resolution, material properties and detail of geometry.","PeriodicalId":117975,"journal":{"name":"2007 IEEE Antennas and Propagation Society International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122903586","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 : 2007-06-09DOI: 10.1109/APS.2007.4396853
Germán Cortés
In this paper we are presenting a novel compact, low profile, non-planar ultra wide band feed that has an input matching better than -11 dB over a decade of frequency bandwidth. In addition, the phase center location of this feed is also invariant over the frequency band.
{"title":"Novel non planar ultra wide band quasi self-complementary antenna","authors":"Germán Cortés","doi":"10.1109/APS.2007.4396853","DOIUrl":"https://doi.org/10.1109/APS.2007.4396853","url":null,"abstract":"In this paper we are presenting a novel compact, low profile, non-planar ultra wide band feed that has an input matching better than -11 dB over a decade of frequency bandwidth. In addition, the phase center location of this feed is also invariant over the frequency band.","PeriodicalId":117975,"journal":{"name":"2007 IEEE Antennas and Propagation Society International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122989239","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 : 2007-06-09DOI: 10.1109/APS.2007.4395670
F. Hoshi, S. Sugawara, T. Minewaki
In this paper, a dielectric-loaded broadband antenna with frequency-insensitive E-plane radiation pattern has been designed. The optimized antenna with a dielectric has more constant and higher gain than the antenna without a dielectric and also has low return loss over wideband. Consequently, it is found that loading a dielectric and designing antenna shape is effective to improve E-plane radiation pattern and return loss simultaneously.
{"title":"A dielectric-loaded broadband antenna with frequency-insensitive E-plane radiation pattern","authors":"F. Hoshi, S. Sugawara, T. Minewaki","doi":"10.1109/APS.2007.4395670","DOIUrl":"https://doi.org/10.1109/APS.2007.4395670","url":null,"abstract":"In this paper, a dielectric-loaded broadband antenna with frequency-insensitive E-plane radiation pattern has been designed. The optimized antenna with a dielectric has more constant and higher gain than the antenna without a dielectric and also has low return loss over wideband. Consequently, it is found that loading a dielectric and designing antenna shape is effective to improve E-plane radiation pattern and return loss simultaneously.","PeriodicalId":117975,"journal":{"name":"2007 IEEE Antennas and Propagation Society International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122997970","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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