Pub Date : 2008-03-05DOI: 10.1109/RWS.2008.4463597
M. Al-Joumayly, N. Behdad
A technique for designing unidirectional miniaturized slot antennas is presented in this paper. Our approach takes advantage of the simultaneous application of two different techniques used to reduce the lateral dimensions of a shallow cavity-backed slot antenna. Reduction of antenna length (including the cavity) is achieved by inductively loading the slot antenna with a number of distributed inductors to increase its electrical length. Reduction of the antenna width is achieved by modifying the ground plane around the slot by using a patterned ground plane with a specific pattern placed around the slot antenna. The combination of these two miniaturization techniques allows for reducing the occupied area by the antenna by a factor larger than 82%.
{"title":"Unidirectional miniaturized slot antennas","authors":"M. Al-Joumayly, N. Behdad","doi":"10.1109/RWS.2008.4463597","DOIUrl":"https://doi.org/10.1109/RWS.2008.4463597","url":null,"abstract":"A technique for designing unidirectional miniaturized slot antennas is presented in this paper. Our approach takes advantage of the simultaneous application of two different techniques used to reduce the lateral dimensions of a shallow cavity-backed slot antenna. Reduction of antenna length (including the cavity) is achieved by inductively loading the slot antenna with a number of distributed inductors to increase its electrical length. Reduction of the antenna width is achieved by modifying the ground plane around the slot by using a patterned ground plane with a specific pattern placed around the slot antenna. The combination of these two miniaturization techniques allows for reducing the occupied area by the antenna by a factor larger than 82%.","PeriodicalId":431471,"journal":{"name":"2008 IEEE Radio and Wireless Symposium","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126579018","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 : 2008-03-05DOI: 10.1109/RWS.2008.4463458
Tang-Nian Luo, Shuen-Yin Bai, Y. Chen, Chun-Lin Ko, Chin-Fong Chiu, Y. Juang
This paper presents a 43 GHz divide-by-three prescaler implemented in 0.13 mum CMOS technology. The variation of regenerative topology is used to perform frequency division by three at millimeter-wave frequency. The band-pass filtering is developed with circuit parasitics to suppress unwanted harmonics. By combining the Gilbert-cell mixer and differential injection locked oscillator, the maximum operating frequency of the CMOS divide-by-three prescaler is elevated to 43 GHz. The measured phase noise is -108.8 dBc/Hz at 1 MHz offset from the output signal frequency. Operated at 2 V, the prescaler consumes 16 mW of power. The total chip size is 0.8times0.6 mm2.
{"title":"A 43 GHz 0.13μm CMOS prescaler","authors":"Tang-Nian Luo, Shuen-Yin Bai, Y. Chen, Chun-Lin Ko, Chin-Fong Chiu, Y. Juang","doi":"10.1109/RWS.2008.4463458","DOIUrl":"https://doi.org/10.1109/RWS.2008.4463458","url":null,"abstract":"This paper presents a 43 GHz divide-by-three prescaler implemented in 0.13 mum CMOS technology. The variation of regenerative topology is used to perform frequency division by three at millimeter-wave frequency. The band-pass filtering is developed with circuit parasitics to suppress unwanted harmonics. By combining the Gilbert-cell mixer and differential injection locked oscillator, the maximum operating frequency of the CMOS divide-by-three prescaler is elevated to 43 GHz. The measured phase noise is -108.8 dBc/Hz at 1 MHz offset from the output signal frequency. Operated at 2 V, the prescaler consumes 16 mW of power. The total chip size is 0.8times0.6 mm2.","PeriodicalId":431471,"journal":{"name":"2008 IEEE Radio and Wireless Symposium","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127620366","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 : 2008-03-05DOI: 10.1109/RWS.2008.4463519
Pouya Aflaki, Renato Negra, F. Ghannouchi
This paper presents the design and implementation of an inverse class-F power amplifier using a commercially available GaN 2 W power transistor. A switch-based model for this transistor was implemented in ADS and used to design this high efficiency amplifier. Simulation results with the developed model show drain efficiency of 79%, more than 19 dB of large-signal gain for an output power of greater than 5 W at 1 GHz. These values are confirmed by measurements, showing the usefulness of the switch-based active device model for this type of switching-mode power amplifiers.
{"title":"Design and implementation of an inverse class-F power amplifier with 79 % efficiency by using a switch-based active device model","authors":"Pouya Aflaki, Renato Negra, F. Ghannouchi","doi":"10.1109/RWS.2008.4463519","DOIUrl":"https://doi.org/10.1109/RWS.2008.4463519","url":null,"abstract":"This paper presents the design and implementation of an inverse class-F power amplifier using a commercially available GaN 2 W power transistor. A switch-based model for this transistor was implemented in ADS and used to design this high efficiency amplifier. Simulation results with the developed model show drain efficiency of 79%, more than 19 dB of large-signal gain for an output power of greater than 5 W at 1 GHz. These values are confirmed by measurements, showing the usefulness of the switch-based active device model for this type of switching-mode power amplifiers.","PeriodicalId":431471,"journal":{"name":"2008 IEEE Radio and Wireless Symposium","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127857502","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 : 2008-03-05DOI: 10.1109/RWS.2008.4463564
A. Amornthipparat, H. Shirai, K. Yonezawa, T. Inoue
Non line of sight (NLOS) path loss has been investigated by using the Shooting and Bouncing Rays (SBR) method. Two building layouts; continuously connected and non-connected building layouts, are used to check the street propagation characteristics and leakage effect due to the building gaps. Based on the statistical data numerically generated buildings are placed along the streets and path loss are evaluated along them. It is found that the predictions by ITU-R model give us somewhat less path loss for our street- cell models.
{"title":"NLOS path loss evaluation for street-cell environment","authors":"A. Amornthipparat, H. Shirai, K. Yonezawa, T. Inoue","doi":"10.1109/RWS.2008.4463564","DOIUrl":"https://doi.org/10.1109/RWS.2008.4463564","url":null,"abstract":"Non line of sight (NLOS) path loss has been investigated by using the Shooting and Bouncing Rays (SBR) method. Two building layouts; continuously connected and non-connected building layouts, are used to check the street propagation characteristics and leakage effect due to the building gaps. Based on the statistical data numerically generated buildings are placed along the streets and path loss are evaluated along them. It is found that the predictions by ITU-R model give us somewhat less path loss for our street- cell models.","PeriodicalId":431471,"journal":{"name":"2008 IEEE Radio and Wireless Symposium","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121023869","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 : 2008-03-05DOI: 10.1109/RWS.2008.4463630
S. Gunnarsson, A. Emrich, H. Zirath, R. Kozhuharov, C. Karnfelt, J. Embretsen, C. Tegnander
A multi-functional single-chip 53 GHz radiometer front-end MMIC has been designed in a commercial GaAs mHEMT technology and evaluated by probed measurements. To the best of the authors' knowledge, this is the first multi-functional MMIC ever presented intended for a radiometer application. Thus, the presented MMIC represents the future in radiometer front-end design, enabling a new generation of radiometers with lower cost, weight and DC power consumption. The MMIC is intended to be used in a demonstrator for a future geostationary synthetic thinned aperture radiometer for satellite-based environmental studies of the earth. Measured results for conversion gain, RF and IF bandwidths, image rejection ratio, 1-dB compression point, input referred third order intercept point (IIP3), LO saturation, and noise figure are presented and discussed. A study of the influence of benzocyclobutene (BCB) as a dielectric coating used for surface passivation on the measured RF performance is also performed. Furthermore, the very important issue of phase stability versus temperature and time was also investigated.
{"title":"A single-chip 53 GHz radiometer front-end MMIC for geostationary atmospheric measurements","authors":"S. Gunnarsson, A. Emrich, H. Zirath, R. Kozhuharov, C. Karnfelt, J. Embretsen, C. Tegnander","doi":"10.1109/RWS.2008.4463630","DOIUrl":"https://doi.org/10.1109/RWS.2008.4463630","url":null,"abstract":"A multi-functional single-chip 53 GHz radiometer front-end MMIC has been designed in a commercial GaAs mHEMT technology and evaluated by probed measurements. To the best of the authors' knowledge, this is the first multi-functional MMIC ever presented intended for a radiometer application. Thus, the presented MMIC represents the future in radiometer front-end design, enabling a new generation of radiometers with lower cost, weight and DC power consumption. The MMIC is intended to be used in a demonstrator for a future geostationary synthetic thinned aperture radiometer for satellite-based environmental studies of the earth. Measured results for conversion gain, RF and IF bandwidths, image rejection ratio, 1-dB compression point, input referred third order intercept point (IIP3), LO saturation, and noise figure are presented and discussed. A study of the influence of benzocyclobutene (BCB) as a dielectric coating used for surface passivation on the measured RF performance is also performed. Furthermore, the very important issue of phase stability versus temperature and time was also investigated.","PeriodicalId":431471,"journal":{"name":"2008 IEEE Radio and Wireless Symposium","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121384299","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 : 2008-03-05DOI: 10.1109/RWS.2008.4463511
D. Jung, K. Eun, C. Park
This paper presents effects of a resonator output load line on the performance of an oscillator. To verify the effects, we designed three low temperature co- fired ceramic (LTCC) circular resonators to fabricate three different Ka-band oscillators. The output load line of the resonator connecting a negative resistance generator monolithic microwave integrated circuit ([-]R MMIC) is a conductor backed coplanar waveguide (CBCPW). We propose load lines with a back pad or a lambda/4 short stub to reduce radiation loss at the opposite side of the load lines. The unloaded Q-value of the two proposed resonators is 255 (25% improvement) and 274 (33.4% improvement) respectively, compared to a conventional resonator with a value of 204. While the measured output power and phase noise of an oscillator with a conventional resonator is 5.0dBm and -95.17dBc/Hz at 1MHz offset, the two oscillators using the proposed resonators with a back pad or lambda/4 short stub are measured at 6.34 dBm, -97.33 dBc/Hz, 16.84 dBm, and -101.17 dBc/Hz, respectively, at the same bias condition. We can see that the radiation loss of the output load line exerts a great influence not only on the Q-value of a resonator but also on the output power and phase noise of an oscillator. As the resonators are embedded in the multilayer LTCC block, they are also very suitable for implementing millimeter-wave integrated system applications.
{"title":"A system-on-package structure LTCC resonator for a low phase noise and power efficient millimeter-wave oscillation","authors":"D. Jung, K. Eun, C. Park","doi":"10.1109/RWS.2008.4463511","DOIUrl":"https://doi.org/10.1109/RWS.2008.4463511","url":null,"abstract":"This paper presents effects of a resonator output load line on the performance of an oscillator. To verify the effects, we designed three low temperature co- fired ceramic (LTCC) circular resonators to fabricate three different Ka-band oscillators. The output load line of the resonator connecting a negative resistance generator monolithic microwave integrated circuit ([-]R MMIC) is a conductor backed coplanar waveguide (CBCPW). We propose load lines with a back pad or a lambda/4 short stub to reduce radiation loss at the opposite side of the load lines. The unloaded Q-value of the two proposed resonators is 255 (25% improvement) and 274 (33.4% improvement) respectively, compared to a conventional resonator with a value of 204. While the measured output power and phase noise of an oscillator with a conventional resonator is 5.0dBm and -95.17dBc/Hz at 1MHz offset, the two oscillators using the proposed resonators with a back pad or lambda/4 short stub are measured at 6.34 dBm, -97.33 dBc/Hz, 16.84 dBm, and -101.17 dBc/Hz, respectively, at the same bias condition. We can see that the radiation loss of the output load line exerts a great influence not only on the Q-value of a resonator but also on the output power and phase noise of an oscillator. As the resonators are embedded in the multilayer LTCC block, they are also very suitable for implementing millimeter-wave integrated system applications.","PeriodicalId":431471,"journal":{"name":"2008 IEEE Radio and Wireless Symposium","volume":"100 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122604561","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 : 2008-03-05DOI: 10.1109/RWS.2008.4463573
A.M. Hisham, H. Arslan
This paper suggests a roadmap for signal intelligence and multidimensional signal analysis in Cognitive Radio and Software-Defined radio (CR/SDR). The paper reviews some methods of linear and quadratic time frequency representation (TFR) as an initiative for multidimensional signal analysis. The paper also addresses recent developments in the use of TFR for CR/SDR applications.
{"title":"Multidimensional signal analysis and measurements for cognitive radio systems","authors":"A.M. Hisham, H. Arslan","doi":"10.1109/RWS.2008.4463573","DOIUrl":"https://doi.org/10.1109/RWS.2008.4463573","url":null,"abstract":"This paper suggests a roadmap for signal intelligence and multidimensional signal analysis in Cognitive Radio and Software-Defined radio (CR/SDR). The paper reviews some methods of linear and quadratic time frequency representation (TFR) as an initiative for multidimensional signal analysis. The paper also addresses recent developments in the use of TFR for CR/SDR applications.","PeriodicalId":431471,"journal":{"name":"2008 IEEE Radio and Wireless Symposium","volume":"124 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123315442","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 : 2008-03-05DOI: 10.1109/RWS.2008.4463536
Qing Zhao, Keqin Liu
We consider the design of an spectrum overlay network where secondary users detect, track, and exploit spectrum opportunities in unslotted primary systems. We develop a decision-theoretic framework for the optimal joint design of the spectrum sensor and tracking and access strategies, and obtain structural solutions. Our results suggest the equivalence between the design of overlay networks in unslotted primary systems and that in slotted primary systems where channel occupancy by primary users can only change at known and fixed time instants. This equivalence points to the possibility of reducing the design of spectrum overlay in unslotted primary systems to that in slotted primary systems, a significantly simpler problem, and porting results available on the latter to the former.
{"title":"Detecting, tracking, and exploiting spectrum opportunities in unslotted primary systems","authors":"Qing Zhao, Keqin Liu","doi":"10.1109/RWS.2008.4463536","DOIUrl":"https://doi.org/10.1109/RWS.2008.4463536","url":null,"abstract":"We consider the design of an spectrum overlay network where secondary users detect, track, and exploit spectrum opportunities in unslotted primary systems. We develop a decision-theoretic framework for the optimal joint design of the spectrum sensor and tracking and access strategies, and obtain structural solutions. Our results suggest the equivalence between the design of overlay networks in unslotted primary systems and that in slotted primary systems where channel occupancy by primary users can only change at known and fixed time instants. This equivalence points to the possibility of reducing the design of spectrum overlay in unslotted primary systems to that in slotted primary systems, a significantly simpler problem, and porting results available on the latter to the former.","PeriodicalId":431471,"journal":{"name":"2008 IEEE Radio and Wireless Symposium","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117121966","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 : 2008-03-05DOI: 10.1109/RWS.2008.4463467
H. Shekhar
This paper models a multi-channel stabilized S-Aloha system with capture. A capture model for single packet reception in a multi-carrier stabilized S-Aloha network is first proposed. This model can be effectively used for both single and multiple antenna base station (BS). A multi-packet reception model is also developed for multi-antenna base stations. In this model, the base station can use any multiuser detection algorithm. Two frame structures are used to allow multiuser detection. An ideal multiuser detector (MUD), i.e. the number of successful users is less than or equal to the number of antennas at the the BS, is considered in this paper. It is shown that for a lightly loaded system, i.e. when rate of new packet generation in the network is low, there might not be enough advantage to use a multiple antenna system in terms of throughput. It is also shown that in a finite user case the maximum attainable stabilized throughput reduces slightly with increasing number of users and very quickly reaches the infinite user case.
{"title":"On the use of LMMSE receiver for single and multiple packet reception in stabilized multi-channel slotted aloha","authors":"H. Shekhar","doi":"10.1109/RWS.2008.4463467","DOIUrl":"https://doi.org/10.1109/RWS.2008.4463467","url":null,"abstract":"This paper models a multi-channel stabilized S-Aloha system with capture. A capture model for single packet reception in a multi-carrier stabilized S-Aloha network is first proposed. This model can be effectively used for both single and multiple antenna base station (BS). A multi-packet reception model is also developed for multi-antenna base stations. In this model, the base station can use any multiuser detection algorithm. Two frame structures are used to allow multiuser detection. An ideal multiuser detector (MUD), i.e. the number of successful users is less than or equal to the number of antennas at the the BS, is considered in this paper. It is shown that for a lightly loaded system, i.e. when rate of new packet generation in the network is low, there might not be enough advantage to use a multiple antenna system in terms of throughput. It is also shown that in a finite user case the maximum attainable stabilized throughput reduces slightly with increasing number of users and very quickly reaches the infinite user case.","PeriodicalId":431471,"journal":{"name":"2008 IEEE Radio and Wireless Symposium","volume":"126 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117345173","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 : 2008-03-05DOI: 10.1109/RWS.2008.4463620
A. Grami
Designing a satellite system presents many challenges, for it is a non-linear optimization problem. Optimization is achieved to meet the satellite's orbital slot, spectrum, mass, real estate, power, and complexity constraints, while accommodating the system's cost, coverage, capacity, networking, performance, and user requirements. In this paper, through optimization of satellite resources and service features, an advanced high-capacity multi-beam high-power GEO bent-pipe V-band satellite system-capable of providing ubiquitous low-cost broadband access to a large user base across North America while employing small low- cost terminals-is proposed.
{"title":"An advanced GEO bentpipe V-band satellite system: Next-generation broadband satellite access","authors":"A. Grami","doi":"10.1109/RWS.2008.4463620","DOIUrl":"https://doi.org/10.1109/RWS.2008.4463620","url":null,"abstract":"Designing a satellite system presents many challenges, for it is a non-linear optimization problem. Optimization is achieved to meet the satellite's orbital slot, spectrum, mass, real estate, power, and complexity constraints, while accommodating the system's cost, coverage, capacity, networking, performance, and user requirements. In this paper, through optimization of satellite resources and service features, an advanced high-capacity multi-beam high-power GEO bent-pipe V-band satellite system-capable of providing ubiquitous low-cost broadband access to a large user base across North America while employing small low- cost terminals-is proposed.","PeriodicalId":431471,"journal":{"name":"2008 IEEE Radio and Wireless Symposium","volume":"87 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115336489","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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