Pub Date : 2013-08-01DOI: 10.1109/IWEM.2013.6888751
H. Arai
This talk presents antenna systems for high power applications to test electric equipment and discuss the issues of measurement facilities. Before releasing new electrical products, EMS (Electromagnetic susceptibility) tests are required to verify whether EUT (Equipment under test) causes the malfunction by a peripheral electromagnetic radiation. The EMS test needs to irradiate EUTs by high electric field in wide frequency range inside anechoic chamber. A problem in this facility is the antenna size in HF band, because the limited chamber space forces to design electrically small antenna with high power handling capability. In addition, EUTs under test are placed in the vicinity of the antenna, it is necessary to predict electric near field distributions. The antenna design for this application, this talk presents a multi-element folded dipole antenna in HF band and a pyramidal horn antenna in UHF band. The technique of antenna parameter optimization to provide high electric field at EUT is discussed in detail. The second topic of antennas for high power applications is the anechoic chamber design including with very small reflection from absorbers. Anechoic chambers do not provide artificial free space for antenna measurements. Small reflections from absorbers generate standing waves inside chamber and change the estimated electric field distributions inside chambers. The antenna design including small reflections from absorbers is also discussed to optimize EMS antennas.
{"title":"Keynote speaker 1: Antennas for high power applications","authors":"H. Arai","doi":"10.1109/IWEM.2013.6888751","DOIUrl":"https://doi.org/10.1109/IWEM.2013.6888751","url":null,"abstract":"This talk presents antenna systems for high power applications to test electric equipment and discuss the issues of measurement facilities. Before releasing new electrical products, EMS (Electromagnetic susceptibility) tests are required to verify whether EUT (Equipment under test) causes the malfunction by a peripheral electromagnetic radiation. The EMS test needs to irradiate EUTs by high electric field in wide frequency range inside anechoic chamber. A problem in this facility is the antenna size in HF band, because the limited chamber space forces to design electrically small antenna with high power handling capability. In addition, EUTs under test are placed in the vicinity of the antenna, it is necessary to predict electric near field distributions. The antenna design for this application, this talk presents a multi-element folded dipole antenna in HF band and a pyramidal horn antenna in UHF band. The technique of antenna parameter optimization to provide high electric field at EUT is discussed in detail. The second topic of antennas for high power applications is the anechoic chamber design including with very small reflection from absorbers. Anechoic chambers do not provide artificial free space for antenna measurements. Small reflections from absorbers generate standing waves inside chamber and change the estimated electric field distributions inside chambers. The antenna design including small reflections from absorbers is also discussed to optimize EMS antennas.","PeriodicalId":119627,"journal":{"name":"2013 IEEE International Workshop on Electromagnetics, Applications and Student Innovation Competition","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131132482","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 : 2013-08-01DOI: 10.1109/IWEM.2013.6888782
Yu-Zhe Zhang, Wai-Lon Chio, Wen-Yao Zhuang, Wai‐Wa Choi, K. Tam
In this paper double equilateral U-shaped defected ground structure (DGS) units are applied to relize a size reduced microstrip crossover for Butler matrix application. By embedding the DGS units the size of the microstrip crossover at 900 MHz can be reduced by 14.6% compare to conventional design.
{"title":"Size reduction of microstrip crossover using defected ground structure and its application in butler matrix","authors":"Yu-Zhe Zhang, Wai-Lon Chio, Wen-Yao Zhuang, Wai‐Wa Choi, K. Tam","doi":"10.1109/IWEM.2013.6888782","DOIUrl":"https://doi.org/10.1109/IWEM.2013.6888782","url":null,"abstract":"In this paper double equilateral U-shaped defected ground structure (DGS) units are applied to relize a size reduced microstrip crossover for Butler matrix application. By embedding the DGS units the size of the microstrip crossover at 900 MHz can be reduced by 14.6% compare to conventional design.","PeriodicalId":119627,"journal":{"name":"2013 IEEE International Workshop on Electromagnetics, Applications and Student Innovation Competition","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125498613","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 : 2013-08-01DOI: 10.1109/IWEM.2013.6888756
Yu Luo, Q. Chu
A novel design method of wideband antennas with stable beamwidth is presented. In this design, the stable radiation pattern is achieved through two parallel dipoles over a big reflector, and wideband impedance match is reached by loading stubs to dipoles to close the first two resonant modes of the dipoles. A simple antenna for LTE base-station is designed in this method, fabricated and measured. Measurement results have a good agreement to simulation ones.
{"title":"Design of wideband antenna with stable beamwidth based on multi-mode and multi-dipole","authors":"Yu Luo, Q. Chu","doi":"10.1109/IWEM.2013.6888756","DOIUrl":"https://doi.org/10.1109/IWEM.2013.6888756","url":null,"abstract":"A novel design method of wideband antennas with stable beamwidth is presented. In this design, the stable radiation pattern is achieved through two parallel dipoles over a big reflector, and wideband impedance match is reached by loading stubs to dipoles to close the first two resonant modes of the dipoles. A simple antenna for LTE base-station is designed in this method, fabricated and measured. Measurement results have a good agreement to simulation ones.","PeriodicalId":119627,"journal":{"name":"2013 IEEE International Workshop on Electromagnetics, Applications and Student Innovation Competition","volume":"8 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133074045","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 : 2013-08-01DOI: 10.1109/IWEM.2013.6888789
K. Chung, S. Kharkovsky
This paper presents a circularly polarized slot-loop antenna excited by a dual-feed mechanism using metamaterial line. Wideband performance was achieved using slot perturbation in conjunction with dual feed. Return loss and axial-ratio bandwidths were measured as 86% and 36%, respectively. Bidirectional radiation was observed with a gain of 4.9 dBic.
{"title":"Metamaterial-line fed circularly polarized slot-loop antenna with wideband performance","authors":"K. Chung, S. Kharkovsky","doi":"10.1109/IWEM.2013.6888789","DOIUrl":"https://doi.org/10.1109/IWEM.2013.6888789","url":null,"abstract":"This paper presents a circularly polarized slot-loop antenna excited by a dual-feed mechanism using metamaterial line. Wideband performance was achieved using slot perturbation in conjunction with dual feed. Return loss and axial-ratio bandwidths were measured as 86% and 36%, respectively. Bidirectional radiation was observed with a gain of 4.9 dBic.","PeriodicalId":119627,"journal":{"name":"2013 IEEE International Workshop on Electromagnetics, Applications and Student Innovation Competition","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124042442","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 : 2013-08-01DOI: 10.1109/IWEM.2013.6888786
Yujian Li, K. Luk
A new 60-GHz dense dielectric (DD) patch antenna composed of a aperture coupled rectangular DD patch antenna and two annular reflectors is proposed. The antenna is totally designed onto printed circuit board (PCB) substrates, which is low-cost and easy to fabricate. A wide impedance bandwidth of wider than 30.8% for |S11| <; -10 dB from 50 to 68.2 GHz is achieved. Stable radiation patterns with low cross polarization and an average gain of 11.5 dBi are also achieved over the 3-dB gain bandwidth of 17.57% from 56.26 to 67.1 GHz. Besides, an estimated efficiency of 87% is found. With the advantages of simple structure, easy fabrication, and good radiation performance, the proposed antenna can be applied to low-cost 60-GHz wireless communication systems.
{"title":"Low-cost aperture coupled 60-GHz dense dielectric patch antenna with annular reflectors","authors":"Yujian Li, K. Luk","doi":"10.1109/IWEM.2013.6888786","DOIUrl":"https://doi.org/10.1109/IWEM.2013.6888786","url":null,"abstract":"A new 60-GHz dense dielectric (DD) patch antenna composed of a aperture coupled rectangular DD patch antenna and two annular reflectors is proposed. The antenna is totally designed onto printed circuit board (PCB) substrates, which is low-cost and easy to fabricate. A wide impedance bandwidth of wider than 30.8% for |S11| <; -10 dB from 50 to 68.2 GHz is achieved. Stable radiation patterns with low cross polarization and an average gain of 11.5 dBi are also achieved over the 3-dB gain bandwidth of 17.57% from 56.26 to 67.1 GHz. Besides, an estimated efficiency of 87% is found. With the advantages of simple structure, easy fabrication, and good radiation performance, the proposed antenna can be applied to low-cost 60-GHz wireless communication systems.","PeriodicalId":119627,"journal":{"name":"2013 IEEE International Workshop on Electromagnetics, Applications and Student Innovation Competition","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128015997","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 : 2013-08-01DOI: 10.1109/IWEM.2013.6888753
Kin‐Lu Wong
Ground antenna concept and its promising applications for handheld communication devices such as the smartphones and tablet computers will be presented. The ground antennas are formed by adding very-small-size radiating elements to combine with the device ground plane to achieve an efficient radiator for multiband/wideband operations. Recent advances in the ground antenna design are addressed. The reconfigurable and tunable ground antennas that can be adaptive to environmental changes or tunable to cover different bands will be discussed. The ground antennas are especially suitable for applications in the 4G slim handheld devices, especially for flexible or bendable devices. The ground antennas are also very promising to form high-isolation antenna systems for MIMO and diversity operations in the slim handheld devices.
{"title":"Keynote speaker 3: Handheld communication device ground antennas: Advances and perspectives","authors":"Kin‐Lu Wong","doi":"10.1109/IWEM.2013.6888753","DOIUrl":"https://doi.org/10.1109/IWEM.2013.6888753","url":null,"abstract":"Ground antenna concept and its promising applications for handheld communication devices such as the smartphones and tablet computers will be presented. The ground antennas are formed by adding very-small-size radiating elements to combine with the device ground plane to achieve an efficient radiator for multiband/wideband operations. Recent advances in the ground antenna design are addressed. The reconfigurable and tunable ground antennas that can be adaptive to environmental changes or tunable to cover different bands will be discussed. The ground antennas are especially suitable for applications in the 4G slim handheld devices, especially for flexible or bendable devices. The ground antennas are also very promising to form high-isolation antenna systems for MIMO and diversity operations in the slim handheld devices.","PeriodicalId":119627,"journal":{"name":"2013 IEEE International Workshop on Electromagnetics, Applications and Student Innovation Competition","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124837324","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 : 2013-08-01DOI: 10.1109/IWEM.2013.6888762
Jin Shi, Longlong Lin, X. Qing, Zhi Ning Chen, H. Tang, Li-Heng Zhou, H. Chu
A dual-loop antenna is proposed to enlarge the interrogation zone of reader antennas used in near-field ultra high frequency (UHF) radio frequency identification (RFID) systems. The dual-loop antenna is composed of two segmented loos with one common side and a double-sided parallel-strip line feeding network. Each loop has a uniform and single direction flowing current itself. By providing reverse-direction flowing current to the two segmented loops, the strong and uniform magnetic field distribution over a large interrogation zone can be achieved. The prototype on FR4 printed borad (PCB) exhibits that the dual-loop antenna achieves the impedance matching over the frequency range from 790 to 1040 MHz and produces strong and uniform magnetic field distribution over an interrogation zone of 308 mm × 150 mm.
为了扩大近场超高频(UHF)射频识别(RFID)系统中读写器天线的询问区，提出了一种双环天线。该双环天线由两个分节的共侧天线和一个双面平行馈线网络组成。每个回路本身都有一个均匀的单向电流。通过向两个分段回路提供反向电流，可以在大范围内实现强而均匀的磁场分布。在FR4印刷电路板(PCB)上的原型表明，双环天线在790 ~ 1040 MHz的频率范围内实现了阻抗匹配，在308 mm × 150 mm的探测区内产生了强而均匀的磁场分布。
{"title":"Electrically large dual-loop antenna for UHF near-field RFID readers","authors":"Jin Shi, Longlong Lin, X. Qing, Zhi Ning Chen, H. Tang, Li-Heng Zhou, H. Chu","doi":"10.1109/IWEM.2013.6888762","DOIUrl":"https://doi.org/10.1109/IWEM.2013.6888762","url":null,"abstract":"A dual-loop antenna is proposed to enlarge the interrogation zone of reader antennas used in near-field ultra high frequency (UHF) radio frequency identification (RFID) systems. The dual-loop antenna is composed of two segmented loos with one common side and a double-sided parallel-strip line feeding network. Each loop has a uniform and single direction flowing current itself. By providing reverse-direction flowing current to the two segmented loops, the strong and uniform magnetic field distribution over a large interrogation zone can be achieved. The prototype on FR4 printed borad (PCB) exhibits that the dual-loop antenna achieves the impedance matching over the frequency range from 790 to 1040 MHz and produces strong and uniform magnetic field distribution over an interrogation zone of 308 mm × 150 mm.","PeriodicalId":119627,"journal":{"name":"2013 IEEE International Workshop on Electromagnetics, Applications and Student Innovation Competition","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122642791","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 : 2013-08-01DOI: 10.1109/IWEM.2013.6888760
W. Che, Wanchen Yang, Hao Wang
Artificial magnetic conductor structures (AMCs) is an effective approach to significantly improve the bandwidth and radiation gain of low-profile antennas. Comparing with other techniques, it needs no extra fabricated processes and takes the merit of easy integration. Three examples of AMC structure-based patch antennas are proposed and experimentally demonstrated. As a result, the 2×2 edge-fed patch antenna array using AMCs can achieve over 4 times bandwidth enhancement and about 3dB peak gain improvement than cavity backed antenna. Comparing with the conventional square AMCs, the patch antenna using the AMCs with inserted-stubs can achieve wider bandwidth and higher and more stable gain. Although low temperature co-fired ceramics (LTCC) substrate has a high permittivity, the relative bandwidth of the mmW LTCC antenna array using AMCs can reach 13.7%, which is about 5 times wider than that of ordinary antenna; meanwhile the peak gain can reach 13.3dBi, the stable gain (±1dB) and radiation pattern in the whole band of interest can be observed also.
{"title":"Investigations of AMC and its applications for performance enhancement of planar antenna arrays","authors":"W. Che, Wanchen Yang, Hao Wang","doi":"10.1109/IWEM.2013.6888760","DOIUrl":"https://doi.org/10.1109/IWEM.2013.6888760","url":null,"abstract":"Artificial magnetic conductor structures (AMCs) is an effective approach to significantly improve the bandwidth and radiation gain of low-profile antennas. Comparing with other techniques, it needs no extra fabricated processes and takes the merit of easy integration. Three examples of AMC structure-based patch antennas are proposed and experimentally demonstrated. As a result, the 2×2 edge-fed patch antenna array using AMCs can achieve over 4 times bandwidth enhancement and about 3dB peak gain improvement than cavity backed antenna. Comparing with the conventional square AMCs, the patch antenna using the AMCs with inserted-stubs can achieve wider bandwidth and higher and more stable gain. Although low temperature co-fired ceramics (LTCC) substrate has a high permittivity, the relative bandwidth of the mmW LTCC antenna array using AMCs can reach 13.7%, which is about 5 times wider than that of ordinary antenna; meanwhile the peak gain can reach 13.3dBi, the stable gain (±1dB) and radiation pattern in the whole band of interest can be observed also.","PeriodicalId":119627,"journal":{"name":"2013 IEEE International Workshop on Electromagnetics, Applications and Student Innovation Competition","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122057845","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 : 2013-08-01DOI: 10.1109/IWEM.2013.6888763
W. Li, K. Leung, X. Fang
The compact differential hollow dielectric resonator antenna (DRA) with an embedded vertical feed is investigated. A printed 180° hybrid rat-race is deployed as the feed network. The vertical feed network has a very small footprint, giving more space for placing microwave components. For demonstration, a hollow cylindrical differential DRA was designed at ~2.4 GHz for WLAN applications. The reflection coefficient, antenna gain, and radiation pattern were simulated using ANSYS HFSS. The simulated results were verified by measurements, and reasonable agreement between the measurement and simulation is observed.
{"title":"Compact differential hollow dielectric resonator antenna with embedded vertical feed","authors":"W. Li, K. Leung, X. Fang","doi":"10.1109/IWEM.2013.6888763","DOIUrl":"https://doi.org/10.1109/IWEM.2013.6888763","url":null,"abstract":"The compact differential hollow dielectric resonator antenna (DRA) with an embedded vertical feed is investigated. A printed 180° hybrid rat-race is deployed as the feed network. The vertical feed network has a very small footprint, giving more space for placing microwave components. For demonstration, a hollow cylindrical differential DRA was designed at ~2.4 GHz for WLAN applications. The reflection coefficient, antenna gain, and radiation pattern were simulated using ANSYS HFSS. The simulated results were verified by measurements, and reasonable agreement between the measurement and simulation is observed.","PeriodicalId":119627,"journal":{"name":"2013 IEEE International Workshop on Electromagnetics, Applications and Student Innovation Competition","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130308410","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 : 2013-08-01DOI: 10.1109/IWEM.2013.6888772
Yuzhe Liu, Hongwen Yang, Yuepeng Yan, Yang Wang
A Monolithic microwave integrated circuit (MMIC) 4X2 switch matrix using 0.5um GaAs PHEMT process has been designed for 0.5-3GHZ application. This switch matrix is composed of four special SPDT switches and a 4-bit logical decoder integrated on a single chip. Inductive Bonding wire and package parasite effect are also taken into consideration. This switch matrix is designed to be controlled by positive voltage. The designed switch matrix shows good performance under all working conditions: the insertion loss is less than 5dB, the isolation is no worse than 30dB, the return loss is better than -12dB, the P1dB is better than 26dBm. The chip size of designed switch matrix is only 1.45mm*1.45mm.
{"title":"A MMIC 4X2 switch matrix for 0.5–3GHZ application","authors":"Yuzhe Liu, Hongwen Yang, Yuepeng Yan, Yang Wang","doi":"10.1109/IWEM.2013.6888772","DOIUrl":"https://doi.org/10.1109/IWEM.2013.6888772","url":null,"abstract":"A Monolithic microwave integrated circuit (MMIC) 4X2 switch matrix using 0.5um GaAs PHEMT process has been designed for 0.5-3GHZ application. This switch matrix is composed of four special SPDT switches and a 4-bit logical decoder integrated on a single chip. Inductive Bonding wire and package parasite effect are also taken into consideration. This switch matrix is designed to be controlled by positive voltage. The designed switch matrix shows good performance under all working conditions: the insertion loss is less than 5dB, the isolation is no worse than 30dB, the return loss is better than -12dB, the P1dB is better than 26dBm. The chip size of designed switch matrix is only 1.45mm*1.45mm.","PeriodicalId":119627,"journal":{"name":"2013 IEEE International Workshop on Electromagnetics, Applications and Student Innovation Competition","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116793880","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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