{"title":"Compact UWB power divider with unequal distribution ratio","authors":"F. Wei, Xiao-wei Shi, P. Qin, Y. Guo","doi":"10.1109/IWAT.2014.6958669","DOIUrl":"https://doi.org/10.1109/IWAT.2014.6958669","url":null,"abstract":"A compact ultra-wideband (UWB) power divider with unequal distribution ratio is proposed in this paper. The UWB power divider is based on the conventional unequal Wilkinson power divider with two folded shunt quarter-wavelength short-circuited stubs separated by quarter-wavelength connecting lines at each output ports. The unequal distribution ratio is achieved by adjusting impedance ratio of two output ports. In addition, a single resistor is properly placed between two output ports for improving isolation. Finally, the simulated results are presented, which are in good agreement with the measured ones.","PeriodicalId":337951,"journal":{"name":"2014 International Workshop on Antenna Technology: Small Antennas, Novel EM Structures and Materials, and Applications (iWAT)","volume":"140 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123340441","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}
W. Jiang, S. Gong, G. Fu, Y.-P. Li, L. Yang, Y. Zhang
{"title":"Design of broad circularly polarized square slot antenna with aCPW-Fed","authors":"W. Jiang, S. Gong, G. Fu, Y.-P. Li, L. Yang, Y. Zhang","doi":"10.1109/IWAT.2014.6958677","DOIUrl":"https://doi.org/10.1109/IWAT.2014.6958677","url":null,"abstract":"The paper presents a novel design for a circularly polarized square slot antenna (CPSSA). The antenna is fed by a coplanar waveguide. An asymmetric slot on the ground is applied to create the circularly polarized wave. By adding two orthogonal stubs embedded on the microstrip feeding-line, both the impedance bandwidth and the axial ratio bandwidth of antenna are increased. The results show that 3dB axial ratio (AR) bandwidth and the impedance bandwidth with S11<;-10dB are 59.2% (1.63 GHz) and 84% (2.1 GHz), respectively.","PeriodicalId":337951,"journal":{"name":"2014 International Workshop on Antenna Technology: Small Antennas, Novel EM Structures and Materials, and Applications (iWAT)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124944536","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}
{"title":"Field tests of a 76GHz automotive radar with the dielectric lens and SAGE algorithm","authors":"Shunsuke Sudo, Y. Kuwahara, Hiroyuki Kamo","doi":"10.1109/IWAT.2014.6958590","DOIUrl":"https://doi.org/10.1109/IWAT.2014.6958590","url":null,"abstract":"Novel automotive radar of 76 GHz band has been manufactured and the field tests have been successfully carried out. The radar features by applying SAGE algorithm to the multi-beam dielectric lens. For simple structure and small size, we used a patch array antenna as feed. Under severe constraints of the size, the lens shape has been designed by multi-objective genetic algorithm. Through the field test, it is confirmed that 2 targets separated by 3.5m can be resolved over the range from 20m to 80m.","PeriodicalId":337951,"journal":{"name":"2014 International Workshop on Antenna Technology: Small Antennas, Novel EM Structures and Materials, and Applications (iWAT)","volume":"403 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122863451","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}
Shen-Yun Wang, Minzhi Guo, Yan Xu, Jinyan Xu, Shanshan Huang
{"title":"Carpet cloak with photonic crystal shield","authors":"Shen-Yun Wang, Minzhi Guo, Yan Xu, Jinyan Xu, Shanshan Huang","doi":"10.1109/IWAT.2014.6958637","DOIUrl":"https://doi.org/10.1109/IWAT.2014.6958637","url":null,"abstract":"In this paper, we report a carpet cloak using photonic crystal layers as an effective shield for substituting the PEC shield in the conventional carpet cloak. This carpet cloak permits communication with the outside when the frequency is out of the forbidden bandgap of the photonic crystal. The lateral shift at the reflection plane, which makes the carpet cloak detectable, is considered and calculated with a Gaussian beam illumination. In order to counteract the lateral shift, we redesign the parameters of the cloaking slab by using the method of transformation optics. Good agreement has been obtained between the adjusted carpet cloak and ideal carpet cloak with a PEC shield.","PeriodicalId":337951,"journal":{"name":"2014 International Workshop on Antenna Technology: Small Antennas, Novel EM Structures and Materials, and Applications (iWAT)","volume":"140 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133127168","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}
{"title":"Low profile ultra-wideband directional antenna operating in low microwave band for brain stroke diagnostic system","authors":"A. Mobashsher, A. Abbosh","doi":"10.1109/IWAT.2014.6958632","DOIUrl":"https://doi.org/10.1109/IWAT.2014.6958632","url":null,"abstract":"Worldwide, brain stroke is the leading cause of disability among adult. Present imaging systems do not offer a low cost and portable solution for the stroke diagnosis. Microwave imaging systems have the potential to provide that solution and substitute, or complement, existing systems. To achieve that target, a wideband antenna operating at the band used for that application with directional radiation for adequate penetration into the human head is needed. This paper introduces a novel ultra-wideband antenna design consisting of a folded dipole-like structure printed on two dielectric slabs of the same size. The antenna covers a 98% fractional bandwidth (0.77 to 2.25 GHz), which is used in head imaging. The antenna exhibits stable directional radiation patterns with an average gain of 4.5 dBi and front to back ratio of 8 dBi. The overall structure of the antenna is equivalent to 0.27i0 × 0.1210 × 0.05 k0, where X0 is the corresponding wavelength at 0.77 GHz, which is a compact and low profile arrayable design suitable for microwave-based head imaging.","PeriodicalId":337951,"journal":{"name":"2014 International Workshop on Antenna Technology: Small Antennas, Novel EM Structures and Materials, and Applications (iWAT)","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116637262","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}
Mohammad Vatankhah Varnoosfaderani, D. Thiel, J. Lu, M. Kanesan
{"title":"Dual mode switched parasitic antenna for on/off body communication channels","authors":"Mohammad Vatankhah Varnoosfaderani, D. Thiel, J. Lu, M. Kanesan","doi":"10.1109/IWAT.2014.6958586","DOIUrl":"https://doi.org/10.1109/IWAT.2014.6958586","url":null,"abstract":"A dual mode, hexagonal patch, switched parasitic array is presented for off-body and on-body communications at the same time. The position of the feed excites two modes (TM11 and TM01) and the antenna resonates at 2.4 and 5 GHz simultaneously. When positioned on the chest, the parasitic elements create a controlled narrow beam off axis and a broad beam on axis simultaneously. The off-axis beam (2.4 GHz) can be used for over body communication while the 5 GHz pattern is suitable for off-body communications link to a data center or wireless receiver.","PeriodicalId":337951,"journal":{"name":"2014 International Workshop on Antenna Technology: Small Antennas, Novel EM Structures and Materials, and Applications (iWAT)","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116280446","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}
{"title":"Recent developments in reflectarrays: Multi-reconfiguration, solar cells, and graphene","authors":"J. Perruisseau-Carrier","doi":"10.1109/IWAT.2014.6958613","DOIUrl":"https://doi.org/10.1109/IWAT.2014.6958613","url":null,"abstract":"This invited presentation will review our recent research activities related to reflectarray antennas [1-9]. First, beamscanning reflectarrays with additional reconfiguration capabilities in polarization or frequency will be discussed, as well as arrays operating over multiple polarizations or frequencies. Second, initial results on the implementation of reflectarray antennas on thin-film solar cell panels will be presented. Finally, we will show how graphene can beneficially be used for implementing the reconfigurable reflectarray concept at terahertz or infrared frequencies.","PeriodicalId":337951,"journal":{"name":"2014 International Workshop on Antenna Technology: Small Antennas, Novel EM Structures and Materials, and Applications (iWAT)","volume":"100 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114591601","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}
{"title":"Research on planar antenna arrays","authors":"R. Jin, Sheng Ye, Xianling Liang, Jun-ping Geng","doi":"10.1109/IWAT.2014.6958620","DOIUrl":"https://doi.org/10.1109/IWAT.2014.6958620","url":null,"abstract":"This paper presents the analytical and experimental works on coping with the popularity in wireless communications, especially in satellite communication. Firstly, the “image element” and “arc-shaped orthogonal feeding network\" technologies are introduced for the single-band single-polarization antenna array design, the cross polarization is suppressed greatly and the antenna gain is improved. Moreover, an arbitrarily shaped planar array design technique is developed so that the antenna can be well conformal with the limited system space. Secondly, the high efficiency design of large scale antenna array in Ku band is introduced for single-band dual-polarizations antenna designs, including both active and passive array combination techniques. Thirdly, dual-band orthogonal-polarization technique is introduced and applied successfully in dual-band antenna array integrated designs, including linear and circular polarization, and then expanded to the multi-band multi-polarization array designs. Last, a digital beam forming array exhibits highly gain flatness in wide scan angle is presented, also, a novel simple yet accurate array calibration method is developed.","PeriodicalId":337951,"journal":{"name":"2014 International Workshop on Antenna Technology: Small Antennas, Novel EM Structures and Materials, and Applications (iWAT)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130610597","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}
I. Sohail, Y. Ranga, L. Matekovits, K. Esselle, Stuart G. Hayt
{"title":"A low-profile single-layer UWB polarization stable FSS for electromagnetic shielding applications","authors":"I. Sohail, Y. Ranga, L. Matekovits, K. Esselle, Stuart G. Hayt","doi":"10.1109/IWAT.2014.6958643","DOIUrl":"https://doi.org/10.1109/IWAT.2014.6958643","url":null,"abstract":"A low-profile frequency selective surface (FSS) exhibiting effective shielding over a large bandwidth is presented. The FSS unit-cell consists of a cross-dipole and a ring printed over the opposite surfaces of a low-cost FR-4 substrate. The design demonstrates a wide 7.5 GHz stopband and provides necessary shielding in both X- and Ka- bands simultaneously. The numerical investigations confirm the shielding behaviour of this FSS with more than 20 dB attenuation and 74% bandwidth in 6.5-14 GHz. Moreover, it shows angular stability for both TE and TM polarization at various angles of incidence up to 45°.","PeriodicalId":337951,"journal":{"name":"2014 International Workshop on Antenna Technology: Small Antennas, Novel EM Structures and Materials, and Applications (iWAT)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130672074","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}
{"title":"Incorporating estimated Green's functions in microwave breast cancer imaging with DORT","authors":"M. Abedin, S. Hay, I. Collings","doi":"10.1109/IWAT.2014.6958627","DOIUrl":"https://doi.org/10.1109/IWAT.2014.6958627","url":null,"abstract":"The decomposition of reversed time (DORT) method is a promising algorithm for microwave breast cancer imaging. However when DORT is applied to breasts with high percentage of glandular tissues, its performance decreases due to differences in the dielectric properties of the physical and computational media. We propose a new method of deriving pair wise permittivities by using the received scattered signals in a multi antenna imaging system. We propose to use the estimated permittivities when computing the Green's function in the backpropagation step of DORT rather than using a nominal global value. We also propose to combine multiple eigenvectors of the time reversal operator. It is observed through simulation that our enhanced DORT method achieves improved focusing accuracy in detecting the breast malignancy.","PeriodicalId":337951,"journal":{"name":"2014 International Workshop on Antenna Technology: Small Antennas, Novel EM Structures and Materials, and Applications (iWAT)","volume":"84 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129708321","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}