Pub Date : 2015-03-04DOI: 10.1109/IWAT.2015.7365269
J. Roberts, R. Ziolkowski
The impedance bandwidth of a near-field resonant parasitic (NFRP) element of an electrically small, metamaterial-inspired Egyptian Axe Dipole (EAD) antenna, can be altered significantly by embedding a non-Foster circuit element into it. The frequency agile behavior of the reactance component internal to the NFRP element of an EAD antenna with a center frequency of 300 MHz is established and a negative impedance converter (NIC) circuit is designed to mimic this behavior. Several other non-Foster circuits have been considered for the NIC implementation and will be discussed in our presentation. A Linvill-based design of the requisite NIC, which contains 4 bipolar junction transistors (BJTs), is presented here. ANSYS HFSS was used for the antenna simulation results; Agilent ADS was used for the circuit simulations. The co-designed, optimized results show an increase in the EAD fractional impedance bandwidth from 0.9% to 46.0%, a factor of over 50 times improvement.
{"title":"Non-foster circuit matching of a near-field resonant parasitic, electrically small antenna","authors":"J. Roberts, R. Ziolkowski","doi":"10.1109/IWAT.2015.7365269","DOIUrl":"https://doi.org/10.1109/IWAT.2015.7365269","url":null,"abstract":"The impedance bandwidth of a near-field resonant parasitic (NFRP) element of an electrically small, metamaterial-inspired Egyptian Axe Dipole (EAD) antenna, can be altered significantly by embedding a non-Foster circuit element into it. The frequency agile behavior of the reactance component internal to the NFRP element of an EAD antenna with a center frequency of 300 MHz is established and a negative impedance converter (NIC) circuit is designed to mimic this behavior. Several other non-Foster circuits have been considered for the NIC implementation and will be discussed in our presentation. A Linvill-based design of the requisite NIC, which contains 4 bipolar junction transistors (BJTs), is presented here. ANSYS HFSS was used for the antenna simulation results; Agilent ADS was used for the circuit simulations. The co-designed, optimized results show an increase in the EAD fractional impedance bandwidth from 0.9% to 46.0%, a factor of over 50 times improvement.","PeriodicalId":342623,"journal":{"name":"2015 International Workshop on Antenna Technology (iWAT)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122078166","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 : 2015-03-04DOI: 10.1109/IWAT.2015.7365360
Wen‐Shan Chen, Chun-Sheng Lin, Hung-Ming Liu
This paper proposes a monopole type MIMO antenna at WLAN band for dongle application. The MIMO antenna consists of two identical monopole antennas on both ends of an FR4 substrate and operates a frequency band at 2.45 GHz. The antenna is fabricated on an FR4 substrate of permittivity of 4.4, thickness of 1.6 mm, and loss tangent of 0.0245. The isolation mechanism is by cutting U-slot and introducing three isolation elements, which are extended from the ground plane; one is located on the center part of the antenna portion and two strips are located symmetrically at the edges of the U-shaped ground. The overall dimensions (25 × 50 mm2) of the proposed MIMO antenna including an antenna portion (14 × 25 mm2) and a system ground (25 × 36 mm2). The prototype is constructed and investigated. Form the design results, the measured S21 within WLAN 2.4GHz band is below -15 dB; the radiation patterns are with an omni-directional characteristic. In addition, the antenna with the simple structure and good performances is suitable for applying in WLAN system of small size.
{"title":"MIMO antennas with U-shaped ground and three protrued strips for WLAN applications","authors":"Wen‐Shan Chen, Chun-Sheng Lin, Hung-Ming Liu","doi":"10.1109/IWAT.2015.7365360","DOIUrl":"https://doi.org/10.1109/IWAT.2015.7365360","url":null,"abstract":"This paper proposes a monopole type MIMO antenna at WLAN band for dongle application. The MIMO antenna consists of two identical monopole antennas on both ends of an FR4 substrate and operates a frequency band at 2.45 GHz. The antenna is fabricated on an FR4 substrate of permittivity of 4.4, thickness of 1.6 mm, and loss tangent of 0.0245. The isolation mechanism is by cutting U-slot and introducing three isolation elements, which are extended from the ground plane; one is located on the center part of the antenna portion and two strips are located symmetrically at the edges of the U-shaped ground. The overall dimensions (25 × 50 mm2) of the proposed MIMO antenna including an antenna portion (14 × 25 mm2) and a system ground (25 × 36 mm2). The prototype is constructed and investigated. Form the design results, the measured S21 within WLAN 2.4GHz band is below -15 dB; the radiation patterns are with an omni-directional characteristic. In addition, the antenna with the simple structure and good performances is suitable for applying in WLAN system of small size.","PeriodicalId":342623,"journal":{"name":"2015 International Workshop on Antenna Technology (iWAT)","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122237448","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 : 2015-03-04DOI: 10.1109/IWAT.2015.7365267
Y. Ban, J. L. Li
Our group works in the eara of phone antennas in recent years will be reviewed. Firstly, some multiband single phone antennas will be presented, especially where the narrow-frame antenna is firstly proposed for the large touch-screen phone applications. Then, some decoupled antennas for LTE MIMO phone applications will be demonstrated, where two different decoupled techniques including well-designed protruded ground and neutralization line are used. Finally, two multiband antennas for metal-ring phone applications are proposed.
{"title":"Multiband LTE/WWAN phone antennas","authors":"Y. Ban, J. L. Li","doi":"10.1109/IWAT.2015.7365267","DOIUrl":"https://doi.org/10.1109/IWAT.2015.7365267","url":null,"abstract":"Our group works in the eara of phone antennas in recent years will be reviewed. Firstly, some multiband single phone antennas will be presented, especially where the narrow-frame antenna is firstly proposed for the large touch-screen phone applications. Then, some decoupled antennas for LTE MIMO phone applications will be demonstrated, where two different decoupled techniques including well-designed protruded ground and neutralization line are used. Finally, two multiband antennas for metal-ring phone applications are proposed.","PeriodicalId":342623,"journal":{"name":"2015 International Workshop on Antenna Technology (iWAT)","volume":"183 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120884501","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 : 2015-03-04DOI: 10.1109/IWAT.2015.7365271
N. Shinohara
Microwave power transfer (MPT) is a long-distance wireless power transfer (WPT) technology. At Kyoto University, since the 1980s, various MPT applications have been proposed and much MPT research has been done. The university has two large anechoic chambers for MPT research, which are open for collaborative studies. With these research facilities, we conducted a beam-forming experiment with a phased array to create a flat-top power beam in the near field with high beam efficiency and the high RF-DC conversion efficiency for a rectifying antenna, which is calculated by a genetic algorithm. On the basis of the university's research activities, we promote commercial MPT applications with a consortium called WiPoT, whose membership comprises 29 companies and 38 universities. In this study, these activities of Kyoto University are introduced.
{"title":"Research and standardization activities of wireless power transfer via microwaves at Kyoto university","authors":"N. Shinohara","doi":"10.1109/IWAT.2015.7365271","DOIUrl":"https://doi.org/10.1109/IWAT.2015.7365271","url":null,"abstract":"Microwave power transfer (MPT) is a long-distance wireless power transfer (WPT) technology. At Kyoto University, since the 1980s, various MPT applications have been proposed and much MPT research has been done. The university has two large anechoic chambers for MPT research, which are open for collaborative studies. With these research facilities, we conducted a beam-forming experiment with a phased array to create a flat-top power beam in the near field with high beam efficiency and the high RF-DC conversion efficiency for a rectifying antenna, which is calculated by a genetic algorithm. On the basis of the university's research activities, we promote commercial MPT applications with a consortium called WiPoT, whose membership comprises 29 companies and 38 universities. In this study, these activities of Kyoto University are introduced.","PeriodicalId":342623,"journal":{"name":"2015 International Workshop on Antenna Technology (iWAT)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126614727","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 : 2015-03-04DOI: 10.1109/IWAT.2015.7365305
Hiroyoshi Yamada, Yosuke Wakamatsu, Kohei Sato, Y. Yamaguchi
MIMO technique can improve system performance not only communication system but also radar system. In this paper, we propose a quasi-MIMO Doppler radar for indoor human detection. In the indoor measurements, multipath reflections by wall, floor, and furniture, often make human detection difficult. Doppler filtering is introduced to remove these undesired response and extract radar echoes by human in motion before target detection. Also virtual array technique based on the Khatri-Rao matrix product is introduced in the MIMO radar detection. Experimental results are reported to shown performance improvement especially in angular resolution.
{"title":"Indoor human detection by using quasi-MIMO Doppler radar","authors":"Hiroyoshi Yamada, Yosuke Wakamatsu, Kohei Sato, Y. Yamaguchi","doi":"10.1109/IWAT.2015.7365305","DOIUrl":"https://doi.org/10.1109/IWAT.2015.7365305","url":null,"abstract":"MIMO technique can improve system performance not only communication system but also radar system. In this paper, we propose a quasi-MIMO Doppler radar for indoor human detection. In the indoor measurements, multipath reflections by wall, floor, and furniture, often make human detection difficult. Doppler filtering is introduced to remove these undesired response and extract radar echoes by human in motion before target detection. Also virtual array technique based on the Khatri-Rao matrix product is introduced in the MIMO radar detection. Experimental results are reported to shown performance improvement especially in angular resolution.","PeriodicalId":342623,"journal":{"name":"2015 International Workshop on Antenna Technology (iWAT)","volume":"61 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124764618","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 : 2015-03-04DOI: 10.1109/IWAT.2015.7365345
Byung‐chul Park, Jeong‐Hae Lee
Two types of circularly polarized (CP) antennas based on metamaterial transmission lines will be presented. First, a dual-band omnidirectional circularly polarized (CP) antenna of epsilon negative (ENG) transmission lines (TLs) is introduced. The antenna is based on a circular mushroom structure with curved branches and designed without additional feeding parts for a 90° phase difference between two orthogonal modes as well as additional radiators for dual-band operations. A left-hand CP (LHCP) and a right-hand CP (RHCP) are obtained at the zeroth and the first order resonance modes, respectively. Second, a circularly polarized (CP) antenna based on mu-negative (MNG) transmission lines (TLs) is presented. The antenna consists of two pairs of resonators for two orthogonal polarizations. The 90° phase difference between them is achieved by detuning the corresponding resonance frequencies. The experimental results agree with the theoretical results.
{"title":"Circularly polarized antennas based on metamaterial transmission lines","authors":"Byung‐chul Park, Jeong‐Hae Lee","doi":"10.1109/IWAT.2015.7365345","DOIUrl":"https://doi.org/10.1109/IWAT.2015.7365345","url":null,"abstract":"Two types of circularly polarized (CP) antennas based on metamaterial transmission lines will be presented. First, a dual-band omnidirectional circularly polarized (CP) antenna of epsilon negative (ENG) transmission lines (TLs) is introduced. The antenna is based on a circular mushroom structure with curved branches and designed without additional feeding parts for a 90° phase difference between two orthogonal modes as well as additional radiators for dual-band operations. A left-hand CP (LHCP) and a right-hand CP (RHCP) are obtained at the zeroth and the first order resonance modes, respectively. Second, a circularly polarized (CP) antenna based on mu-negative (MNG) transmission lines (TLs) is presented. The antenna consists of two pairs of resonators for two orthogonal polarizations. The 90° phase difference between them is achieved by detuning the corresponding resonance frequencies. The experimental results agree with the theoretical results.","PeriodicalId":342623,"journal":{"name":"2015 International Workshop on Antenna Technology (iWAT)","volume":"668 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131886984","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 : 2015-03-04DOI: 10.1109/IWAT.2015.7365288
G. Kwon, K. Hwang, Youngoo Yang, Kangyoon Lee, C. Seo
The electrostatic boundary-value problem of a dielectric-wedge-backed, slotted conducting wedge is solved to analyze an asymmetric coplanar striplines (ACPS) by using the Mellin transform and a mode-matching method. Numerical computations are performed to assess the characteristics of the ACPS in terms of the strip geometry and relative permittivity of a dielectric substrate. In order to check the validity of our theoretical approach, the computed results are compared with the simulation results as well as the results by the conformal mapping.
{"title":"Capacitance computation of asymmetric coplanar striplines by the mellin transform approach","authors":"G. Kwon, K. Hwang, Youngoo Yang, Kangyoon Lee, C. Seo","doi":"10.1109/IWAT.2015.7365288","DOIUrl":"https://doi.org/10.1109/IWAT.2015.7365288","url":null,"abstract":"The electrostatic boundary-value problem of a dielectric-wedge-backed, slotted conducting wedge is solved to analyze an asymmetric coplanar striplines (ACPS) by using the Mellin transform and a mode-matching method. Numerical computations are performed to assess the characteristics of the ACPS in terms of the strip geometry and relative permittivity of a dielectric substrate. In order to check the validity of our theoretical approach, the computed results are compared with the simulation results as well as the results by the conformal mapping.","PeriodicalId":342623,"journal":{"name":"2015 International Workshop on Antenna Technology (iWAT)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131756125","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 : 2015-03-04DOI: 10.1109/IWAT.2015.7365319
K. Sakakibara, Y. Hirayama, T. Araki, N. Kikuma
Two types of millimeter-wave planar array antennas for electronic beam-scanning systems are developed in this work. Several vertically-long sub-arrays are arranged horizontally for beam forming in array signal processing of horizontal plane. On the other hand, the vertically-long sub-arrays are developed in travelling-wave design. The travelling-wave feeding system is advantageous for simple configuration and low-loss operation in millimeter-wave band. Waveguide antennas and microstrip antennas are developed for sub-arrays of electronic beam-scanning systems. Features and advantages of microstrip antennas and waveguide antennas designed for beam-scanning systems are discussed in this paper.
{"title":"Planar array antennas for sub-arrays of electronic beam-scanning systems in millimeter-wave band","authors":"K. Sakakibara, Y. Hirayama, T. Araki, N. Kikuma","doi":"10.1109/IWAT.2015.7365319","DOIUrl":"https://doi.org/10.1109/IWAT.2015.7365319","url":null,"abstract":"Two types of millimeter-wave planar array antennas for electronic beam-scanning systems are developed in this work. Several vertically-long sub-arrays are arranged horizontally for beam forming in array signal processing of horizontal plane. On the other hand, the vertically-long sub-arrays are developed in travelling-wave design. The travelling-wave feeding system is advantageous for simple configuration and low-loss operation in millimeter-wave band. Waveguide antennas and microstrip antennas are developed for sub-arrays of electronic beam-scanning systems. Features and advantages of microstrip antennas and waveguide antennas designed for beam-scanning systems are discussed in this paper.","PeriodicalId":342623,"journal":{"name":"2015 International Workshop on Antenna Technology (iWAT)","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132649532","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}
Antenna diversity performance assessment measures are essential to multi-antenna systems. Among different evaluation metrics, the effective diversity gain is the ultimate ones since not only antenna characteristics but also environment factors are accounted. However, the conventional effective diversity gain measurement process is time consuming and labor intensive process. A semi-automatic measurement system is hence proposed in this work. Multiple antennas are connected to power detectors, which are controlled by a computer controlled AD/DA card. The system control program is coded in Labview. The whole system is mounted on a push cart. During the measurement process, the cart is moved manually in a multipath rich environment. Power levels received by antennas are recorded automatically. The proposed system can significantly reduce the time and labor required for the measurement. Measured data can be processed to yield the effective diversity gain of the tested multi-antenna system.
{"title":"Development of a semi-automatic effective diversity gain measurement system for multi-antenna systems","authors":"Bang-Yun Dai, Wen-Jiao Liao, Yi-Ane Chen, Xin-Xiong Chen","doi":"10.1109/IWAT.2015.7365365","DOIUrl":"https://doi.org/10.1109/IWAT.2015.7365365","url":null,"abstract":"Antenna diversity performance assessment measures are essential to multi-antenna systems. Among different evaluation metrics, the effective diversity gain is the ultimate ones since not only antenna characteristics but also environment factors are accounted. However, the conventional effective diversity gain measurement process is time consuming and labor intensive process. A semi-automatic measurement system is hence proposed in this work. Multiple antennas are connected to power detectors, which are controlled by a computer controlled AD/DA card. The system control program is coded in Labview. The whole system is mounted on a push cart. During the measurement process, the cart is moved manually in a multipath rich environment. Power levels received by antennas are recorded automatically. The proposed system can significantly reduce the time and labor required for the measurement. Measured data can be processed to yield the effective diversity gain of the tested multi-antenna system.","PeriodicalId":342623,"journal":{"name":"2015 International Workshop on Antenna Technology (iWAT)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132858124","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 : 2015-03-04DOI: 10.1109/IWAT.2015.7365293
H. Tran, I. Park
A planar, inductively coupled-fed, crossed dipole with broadband characteristics is proposed for an ultra-high frequency radio frequency identification tag. By using an inductively coupled feeding technique, the proposed tag antenna achieves a good conjugate impedance matching with the tag chip and yields a -10 dB impedance bandwidth of 92 MHz.
{"title":"Compact crossed dipole antenna for a broadband UHF-RFID tag","authors":"H. Tran, I. Park","doi":"10.1109/IWAT.2015.7365293","DOIUrl":"https://doi.org/10.1109/IWAT.2015.7365293","url":null,"abstract":"A planar, inductively coupled-fed, crossed dipole with broadband characteristics is proposed for an ultra-high frequency radio frequency identification tag. By using an inductively coupled feeding technique, the proposed tag antenna achieves a good conjugate impedance matching with the tag chip and yields a -10 dB impedance bandwidth of 92 MHz.","PeriodicalId":342623,"journal":{"name":"2015 International Workshop on Antenna Technology (iWAT)","volume":"245 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133642306","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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