Pub Date : 2018-12-01DOI: 10.1109/ISAPE.2018.8634203
Sen Wang, Hao Li, Yunpeng Zhang, Jiawei Long, E. Li
A broadband circular polarization antenna based on the composite structure of planar spiral and longitudinal helix is presented. Compared to single spiral antenna or helix antenna, proposed antenna has a better performance at low frequency by introducing two longitudinal helix arms connecting with the terminal of the planar spiral arms. As a result, the return loss, axial ratio (AR) and gain are both improved without increasing the antenna size. The antenna is designed to operate from 2 to 18 GHz and has a physical dimension of $boldsymbol{varphi} 50times 45 mathbf{mm}^{3}$. A prototype was fabricated and tested, the results show that the proposed antenna can provide an AR of less than 2.5 dB, a return loss of less than −15 dB and a gain of greater than 0.5 dBi.
{"title":"A Helix-loaded Equiangular Spiral Antenna with Compact Structure","authors":"Sen Wang, Hao Li, Yunpeng Zhang, Jiawei Long, E. Li","doi":"10.1109/ISAPE.2018.8634203","DOIUrl":"https://doi.org/10.1109/ISAPE.2018.8634203","url":null,"abstract":"A broadband circular polarization antenna based on the composite structure of planar spiral and longitudinal helix is presented. Compared to single spiral antenna or helix antenna, proposed antenna has a better performance at low frequency by introducing two longitudinal helix arms connecting with the terminal of the planar spiral arms. As a result, the return loss, axial ratio (AR) and gain are both improved without increasing the antenna size. The antenna is designed to operate from 2 to 18 GHz and has a physical dimension of $boldsymbol{varphi} 50times 45 mathbf{mm}^{3}$. A prototype was fabricated and tested, the results show that the proposed antenna can provide an AR of less than 2.5 dB, a return loss of less than −15 dB and a gain of greater than 0.5 dBi.","PeriodicalId":297368,"journal":{"name":"2018 12th International Symposium on Antennas, Propagation and EM Theory (ISAPE)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128789348","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 : 2018-12-01DOI: 10.1109/ISAPE.2018.8634373
Fengli Xue, F. Xu
The scattering of a 3-D deterministic forest scene is calculated for simulating the synthetic aperture radar(SAR) image. The generated trees are simplified as a cluster of slim cylinders and disks with the deterministic location, orientation and dielectric constant, which are used for coherent scattering calculation. To ensure the accuracy of coherent scattering calculation, the validity of the generalized Rayleigh-Gans (GRG) approximation and the infinite cylinder approximation are verified. The scattering of tree's components is verified by comparing the imaging results of the calculated data and the simulated data.
{"title":"Scattering verification and imaging of vegetation and its components","authors":"Fengli Xue, F. Xu","doi":"10.1109/ISAPE.2018.8634373","DOIUrl":"https://doi.org/10.1109/ISAPE.2018.8634373","url":null,"abstract":"The scattering of a 3-D deterministic forest scene is calculated for simulating the synthetic aperture radar(SAR) image. The generated trees are simplified as a cluster of slim cylinders and disks with the deterministic location, orientation and dielectric constant, which are used for coherent scattering calculation. To ensure the accuracy of coherent scattering calculation, the validity of the generalized Rayleigh-Gans (GRG) approximation and the infinite cylinder approximation are verified. The scattering of tree's components is verified by comparing the imaging results of the calculated data and the simulated data.","PeriodicalId":297368,"journal":{"name":"2018 12th International Symposium on Antennas, Propagation and EM Theory (ISAPE)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132598768","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 : 2018-12-01DOI: 10.1109/ISAPE.2018.8634293
Lei Wang, Wenxiao Fang, Y. En, Yun Huang, Weiheng Shao, Bin Yao
This letter presents a new broadband circularly polarized (CP) monopole antenna with modified ground. The proposed antenna fed by coaxial probe consists of a square ground loaded with an L-shaped branch, which is capable of generating broadband CP radiation. In addition, an I-shaped slit is embedded into the ground plane to improve the impedance matching. The presented antenna has a 10 dB return loss bandwidth from 1.82 to 4.21 GHz (79.3% centered at 3.02 GHz), and a wide 3 dB axial-ratio (AR) bandwidth from 1.84 to 3.95 GHz (72.9% centered at 2.89 GHz). The measured gains are greater than 2.0 dBic in the AR band, and the gain variation within the AR band is less than 1 dBic, which means a good flat gain feature in the broad frequency band. Both the simulated and measured results validate the proposed design.
{"title":"A New Broadband Circularly Polarized Monopole Antenna With Modified Ground","authors":"Lei Wang, Wenxiao Fang, Y. En, Yun Huang, Weiheng Shao, Bin Yao","doi":"10.1109/ISAPE.2018.8634293","DOIUrl":"https://doi.org/10.1109/ISAPE.2018.8634293","url":null,"abstract":"This letter presents a new broadband circularly polarized (CP) monopole antenna with modified ground. The proposed antenna fed by coaxial probe consists of a square ground loaded with an L-shaped branch, which is capable of generating broadband CP radiation. In addition, an I-shaped slit is embedded into the ground plane to improve the impedance matching. The presented antenna has a 10 dB return loss bandwidth from 1.82 to 4.21 GHz (79.3% centered at 3.02 GHz), and a wide 3 dB axial-ratio (AR) bandwidth from 1.84 to 3.95 GHz (72.9% centered at 2.89 GHz). The measured gains are greater than 2.0 dBic in the AR band, and the gain variation within the AR band is less than 1 dBic, which means a good flat gain feature in the broad frequency band. Both the simulated and measured results validate the proposed design.","PeriodicalId":297368,"journal":{"name":"2018 12th International Symposium on Antennas, Propagation and EM Theory (ISAPE)","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132622119","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 : 2018-12-01DOI: 10.1109/ISAPE.2018.8634341
Zi-Jian Han, Wei Song, Yulong Zhu, X. Sheng
A novel low profile EBG is proposed to reduce the radar cross section (RCS) and enhance the gain for patch antenna. The proposed antenna shows low scattering performance for both x- and y-polarization at boresight. Different with conventional low RCS reflector designed by using chessboard-like structure, this design makes use of one-dimensional (1-D) periodic metasurface and need fewer metamaterial cells. Full wave simulation results show that RCS can be reduced more than 13dB at 11.2GHz by the proposed slotted EBG. Except for the RCS reduction, the broadside gain can be obviously enhanced over the antenna operating frequency bandwidth from 10.55GHz to 12GHz (12.9%).
{"title":"RCS Reduction and Gain Enhancement for Patch Antenna by Using Low Profile EBG","authors":"Zi-Jian Han, Wei Song, Yulong Zhu, X. Sheng","doi":"10.1109/ISAPE.2018.8634341","DOIUrl":"https://doi.org/10.1109/ISAPE.2018.8634341","url":null,"abstract":"A novel low profile EBG is proposed to reduce the radar cross section (RCS) and enhance the gain for patch antenna. The proposed antenna shows low scattering performance for both x- and y-polarization at boresight. Different with conventional low RCS reflector designed by using chessboard-like structure, this design makes use of one-dimensional (1-D) periodic metasurface and need fewer metamaterial cells. Full wave simulation results show that RCS can be reduced more than 13dB at 11.2GHz by the proposed slotted EBG. Except for the RCS reduction, the broadside gain can be obviously enhanced over the antenna operating frequency bandwidth from 10.55GHz to 12GHz (12.9%).","PeriodicalId":297368,"journal":{"name":"2018 12th International Symposium on Antennas, Propagation and EM Theory (ISAPE)","volume":"94 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133527605","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 : 2018-12-01DOI: 10.1109/isape.2018.8634364
Fuling Zhao, Yongjun Wang, Shaolin He
There are different interferences in the satellite communication. A example is given in the paper, it is shown from the simulation that when using smart antenna and PASTd algorithm in the satellite communication, the radiation patterns formed by smart antenna points a main beam in the direction of the desired signal but the ability to cancel inferences.
{"title":"Constraining interference in satellite reception and ground station receiver","authors":"Fuling Zhao, Yongjun Wang, Shaolin He","doi":"10.1109/isape.2018.8634364","DOIUrl":"https://doi.org/10.1109/isape.2018.8634364","url":null,"abstract":"There are different interferences in the satellite communication. A example is given in the paper, it is shown from the simulation that when using smart antenna and PASTd algorithm in the satellite communication, the radiation patterns formed by smart antenna points a main beam in the direction of the desired signal but the ability to cancel inferences.","PeriodicalId":297368,"journal":{"name":"2018 12th International Symposium on Antennas, Propagation and EM Theory (ISAPE)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116945873","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 : 2018-12-01DOI: 10.1109/ISAPE.2018.8634116
Min Zhang, Lianyan Zhu
In the analysis of electromagnetic characters around the buildings, the effects of ground are non-ignorable. To solve the problem, a half-space FDTD method with nonuniform meshes is proposed in this paper. Two 1-D modified FDTD equations have been employed to set TF/SF boundary of the infinite half-space electromagnetic problems, then the half space problem can be solved in finite space. A method with non-uniform meshes is applied to reduce the calculation time and meshes of the building with an electrically large structure. Finally, the electromagnetic fields in Building which illuminated by the airborne antenna array is analysed.
{"title":"Analysis of Electromagnetic Distribution in Building Illuminated with Airborne Antenna Array by Using a Half-space FDTD","authors":"Min Zhang, Lianyan Zhu","doi":"10.1109/ISAPE.2018.8634116","DOIUrl":"https://doi.org/10.1109/ISAPE.2018.8634116","url":null,"abstract":"In the analysis of electromagnetic characters around the buildings, the effects of ground are non-ignorable. To solve the problem, a half-space FDTD method with nonuniform meshes is proposed in this paper. Two 1-D modified FDTD equations have been employed to set TF/SF boundary of the infinite half-space electromagnetic problems, then the half space problem can be solved in finite space. A method with non-uniform meshes is applied to reduce the calculation time and meshes of the building with an electrically large structure. Finally, the electromagnetic fields in Building which illuminated by the airborne antenna array is analysed.","PeriodicalId":297368,"journal":{"name":"2018 12th International Symposium on Antennas, Propagation and EM Theory (ISAPE)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116951837","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 : 2018-12-01DOI: 10.1109/ISAPE.2018.8634047
Caicheng Hua, Shikai Wang, Chengfeng Zhang
Using the short-wave two-dimensional antenna array, the high-frequency (3MHz∼30MHz) backscatter sweep-elevation ionogram is obtained for the first time in China. Combining genetic algorithm and Otsu method, the signal region is extracted from the group path-frequency-energy three-dimensional ionogram, and the discrete point noise is eliminated by the connected domain labeling method. The Canny operator is used to obtain the nearest and farthest group path of the echo signal distribution corresponding to each frequency. On the group path-frequency-elevation three-dimensional ionogram, the elevation angle-group path distribution data of the corresponding frequency is acquired to obtain the elevation angle-group path point. The points are fitted by linear curve fitting, logarithmic fitting of the elevation angle, and logarithmic fitting of the group path. Finally, the error analysis of the fitted curve is carried out by the ionospheric data of the Qingdao Station. The results show that the curve obtained by logarithm fitting the group distance is in good agreement with the target curve.
{"title":"Research on method of extraction elevation angle from backscatter ionogram","authors":"Caicheng Hua, Shikai Wang, Chengfeng Zhang","doi":"10.1109/ISAPE.2018.8634047","DOIUrl":"https://doi.org/10.1109/ISAPE.2018.8634047","url":null,"abstract":"Using the short-wave two-dimensional antenna array, the high-frequency (3MHz∼30MHz) backscatter sweep-elevation ionogram is obtained for the first time in China. Combining genetic algorithm and Otsu method, the signal region is extracted from the group path-frequency-energy three-dimensional ionogram, and the discrete point noise is eliminated by the connected domain labeling method. The Canny operator is used to obtain the nearest and farthest group path of the echo signal distribution corresponding to each frequency. On the group path-frequency-elevation three-dimensional ionogram, the elevation angle-group path distribution data of the corresponding frequency is acquired to obtain the elevation angle-group path point. The points are fitted by linear curve fitting, logarithmic fitting of the elevation angle, and logarithmic fitting of the group path. Finally, the error analysis of the fitted curve is carried out by the ionospheric data of the Qingdao Station. The results show that the curve obtained by logarithm fitting the group distance is in good agreement with the target curve.","PeriodicalId":297368,"journal":{"name":"2018 12th International Symposium on Antennas, Propagation and EM Theory (ISAPE)","volume":"108 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131078341","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 : 2018-12-01DOI: 10.1109/ISAPE.2018.8634346
Chao-long Liu, Yi Li, Yang Li
This paper has explained the defects in the traditional passive adaptive cancellation technology under the tight coupling interference, introduced an active adaptive cancellation technology (AACT), and offered a mathematical model of the active adaptive cancellation system, as well as the formulae of interference cancellation ratio (ICR) and convergence time for simulation and experiment. The results show that the system is characterized by high ICR and short convergence time and that the AACT can effectively deal with the tight coupling interference and its application can expand further.
{"title":"Research on Active Adaptive Cancellation Technology for Tight Coupling Interference","authors":"Chao-long Liu, Yi Li, Yang Li","doi":"10.1109/ISAPE.2018.8634346","DOIUrl":"https://doi.org/10.1109/ISAPE.2018.8634346","url":null,"abstract":"This paper has explained the defects in the traditional passive adaptive cancellation technology under the tight coupling interference, introduced an active adaptive cancellation technology (AACT), and offered a mathematical model of the active adaptive cancellation system, as well as the formulae of interference cancellation ratio (ICR) and convergence time for simulation and experiment. The results show that the system is characterized by high ICR and short convergence time and that the AACT can effectively deal with the tight coupling interference and its application can expand further.","PeriodicalId":297368,"journal":{"name":"2018 12th International Symposium on Antennas, Propagation and EM Theory (ISAPE)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131278084","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 : 2018-12-01DOI: 10.1109/ISAPE.2018.8634268
Yunzhou Zhu, Zhongxin Deng, T. Xu
The statistical characteristics of mid-low latitude ionospheric E-region field-aligned irregularities (FAI) observed with the Kunming very high-frequency (VHF) radar are presented. First, the observational results show that the irregularities appeared mainly in periods before noon and near night, with the nighttime echoes being more intense and covering a greater height extent than that during the daytime. Second, we observed the existence of two well-defined types of echoes in the nighttime: the lower E-region echoes (115-130km) and upper E-region echoes (130-150km). Moreover, there are differences in FAI's motion characteristics at different range in the daytime and nighttime. Without in-field measurements, it is difficult to verify what physical mechanisms may explain the formation of the irregularities, which we will combine other facilities to analyze it in the future.
{"title":"Investigations of Ionospheric E-region Field-aligned Irregularities Observed with Kunming VHF Radar","authors":"Yunzhou Zhu, Zhongxin Deng, T. Xu","doi":"10.1109/ISAPE.2018.8634268","DOIUrl":"https://doi.org/10.1109/ISAPE.2018.8634268","url":null,"abstract":"The statistical characteristics of mid-low latitude ionospheric E-region field-aligned irregularities (FAI) observed with the Kunming very high-frequency (VHF) radar are presented. First, the observational results show that the irregularities appeared mainly in periods before noon and near night, with the nighttime echoes being more intense and covering a greater height extent than that during the daytime. Second, we observed the existence of two well-defined types of echoes in the nighttime: the lower E-region echoes (115-130km) and upper E-region echoes (130-150km). Moreover, there are differences in FAI's motion characteristics at different range in the daytime and nighttime. Without in-field measurements, it is difficult to verify what physical mechanisms may explain the formation of the irregularities, which we will combine other facilities to analyze it in the future.","PeriodicalId":297368,"journal":{"name":"2018 12th International Symposium on Antennas, Propagation and EM Theory (ISAPE)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132426529","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 : 2018-12-01DOI: 10.1109/ISAPE.2018.8634324
Xiong-jie Jin, Shuoguang Wang, You-wei Liu
This paper presents a new type of wide-bandwidth beam antenna, which uses a relatively new type of cross-type microstrip dipole. This form has a wider −3dB beamwidth than ordinary microstrip antennas. The radiation profile uses a gradation profile and widens the bandwidth of the antenna by adding parasitic structures and increasing the air frame height. Antenna structure parameters are optimized using ANSYS HFSS. What the test results display is that the 1 port and 2 port standing wave's relative bandwidth <−7.5dB of designed antenna unit reach 35.9% and 22.8%, the central frequency E-plane and H-plane beam width are 110 ° and 91 °, respectively, which facilitates large-angle scanning. This antenna is an orthogonal two-line polarized antenna with a zenith-directional line polarization cross-polarization level of −19.55 dB. With the help of software Matlab, we use sparse Focuss algorithm obtain the antenna array composed of 64 units. The gain reaches 19.61dB when the scanning angle is 60°. It was verified that this antenna element and sparse array have good characteristics.
{"title":"Broadband Wide Beam Dual Polarization Antenna Unit and Its Sparse Array","authors":"Xiong-jie Jin, Shuoguang Wang, You-wei Liu","doi":"10.1109/ISAPE.2018.8634324","DOIUrl":"https://doi.org/10.1109/ISAPE.2018.8634324","url":null,"abstract":"This paper presents a new type of wide-bandwidth beam antenna, which uses a relatively new type of cross-type microstrip dipole. This form has a wider −3dB beamwidth than ordinary microstrip antennas. The radiation profile uses a gradation profile and widens the bandwidth of the antenna by adding parasitic structures and increasing the air frame height. Antenna structure parameters are optimized using ANSYS HFSS. What the test results display is that the 1 port and 2 port standing wave's relative bandwidth <−7.5dB of designed antenna unit reach 35.9% and 22.8%, the central frequency E-plane and H-plane beam width are 110 ° and 91 °, respectively, which facilitates large-angle scanning. This antenna is an orthogonal two-line polarized antenna with a zenith-directional line polarization cross-polarization level of −19.55 dB. With the help of software Matlab, we use sparse Focuss algorithm obtain the antenna array composed of 64 units. The gain reaches 19.61dB when the scanning angle is 60°. It was verified that this antenna element and sparse array have good characteristics.","PeriodicalId":297368,"journal":{"name":"2018 12th International Symposium on Antennas, Propagation and EM Theory (ISAPE)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132453754","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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