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Seyed Hassan Sedighy - One of the best experts on this subject based on the ideXlab platform.
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Ultra Wideband Radar Cross Section Reduction by using non-Resonant Unit Cells.
Scientific reports, 2020Co-Authors: Morteza Nadi, Seyed Hassan Sedighy, Mohamad Khalaj-amirhosseiniAbstract:A general approach is proposed to design ultra-wideband radar cross Section Reduction (RCSR) metasurface by using non-resonant unit cells in chessboard arrangement. The proposed miniaturized artificial magnetic conductor unit cell is composed of two stacked non-resonant patches separated from one another by thin dielectric substrates. The genetic optimization algorithm is used to optimize the unit cell design parameters and obtain wide 10-dB RCSR bandwidth. The proposed approach is performed to design three different RCSR metasurfaces, ideal, ROGERS and low cost. The low cost RCSR metasurface composed of low cost commercially available FR-4 substrate is fabricated and tested which reduces RCS more than 10-dB from 5.22 GHz to 30.85 GHz, 142% fractional bandwidth. This metasurface has significantly wider RCSR bandwidth rather than the state of the art references as well as low cost, simple and light weight structure which facilities its practical applications.
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Ultra Wideband Radar Cross Section Reduction by Using Polarization Conversion Metasurfaces
Scientific reports, 2019Co-Authors: Edris Ameri, Seyed Hassan Esmaeli, Seyed Hassan SedighyAbstract:In this paper, a polarization conversion metasurface (PCM) is designed for ultra wideband radar cross Section (RCS) Reduction. The proposed polarization conversion metasurface consists of double-heads arrow unit cell with its 90°, 180° and 270° rotated ones to create the destructive interferences cancellation and radar cross Section (RCS) Reduction, consequently. The proposed metasurface demonstrates ultra-wide band 10-dB RCS Reduction from 9 to 40 GHz (126.5%) for normally TM- and TE- polarized incident waves. The good agreement between the simulation and measurement results at 0°, 20° and 40° incident angles prove the idea, also. The ultra wideband RCS Reduction of the proposed metasurface as well as its low profile, light weight and low cost prove its high capability compared with the state of the art references.
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Wide band radar cross Section Reduction by thin AMC structure
AEU - International Journal of Electronics and Communications, 2018Co-Authors: Edris Ameri, Seyed Hassan Esmaeli, Seyed Hassan SedighyAbstract:Abstract A new thin and wideband RCS Reduction metasurface is designed and fabricated by using two different AMC unit cell tiles arranged in chessboard like configuration. One of these tiles is formed by saltire arrow unit cells, whereas the other one is formed by Jerusalem unit cells which are designed to achieve out phase difference at broad frequency range. This metasurface reduces the RCS more than 10-dB from 15.75 GHz to 41.3 GHz (90% bandwidth). The designed metasurface works properly at both TE and TM propagation modes, also. Moreover, it has stable 10-dB RCS Reduction bandwidth for TM propagation mode up to 50° oblique incident angle and 30° for TE ones. These good specifications prove the designed metasurface capability compared with the state of the art references.
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Wideband radar cross-Section Reduction by AMC
Electronics Letters, 2016Co-Authors: Seyed Hassan Esmaeli, Seyed Hassan SedighyAbstract:A new planar wideband chessboard structure is designed to reduce the radar cross-Section (RCS) of an object. This proposed chessboard configuration is composed of two different artificial magnetic conductor (AMC) tiles. One of these tiles is formed by saltire arrow unit cells, whereas the other one is formed by four E-shaped ones. A 180° ± 30° phase difference between these tiles achieved by precise design of the AMC unit cells of more than 9.4–23.28 GHz (85%) reduces the RCS by more than 10 dB. The fabricated board results show very good agreement with the simulated ones, which verify the ability and capability of the proposed structure.
Edris Ameri - One of the best experts on this subject based on the ideXlab platform.
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Ultra-Wideband radar cross Section Reduction by thin AMC metasurface
2020Co-Authors: Seyed Hassan Esmaeli, Edris Ameri, Seyyed Hassan SedighyAbstract:An ultra-wideband thin metasurface is designed and fabricated to reduce the radar cross-Section (RCS) from 9.72 GHz to 26.77 GHz (93 % bandwidth) more than 10 dB. The proposed metasurface is composed of two different artificial magnetic conductor (AMC) tiles with about 180° reflection phase differences to destruct the reflected wave over ultra-wideband frequency. Although the designed tiles have similar unit cell configuration, their reflected phase responses are properly tuned by changing the dimensions. The comparison between the proposed AMC metasurface and some sate of the art references clearly proves the high RCS Reduction bandwidth with very low thickness of the designed AMC metasurface rather than the references. The measured results are in good agreement with the simulation ones which prove the idea.
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Ultra Wideband Radar Cross Section Reduction by Using Polarization Conversion Metasurfaces
Scientific reports, 2019Co-Authors: Edris Ameri, Seyed Hassan Esmaeli, Seyed Hassan SedighyAbstract:In this paper, a polarization conversion metasurface (PCM) is designed for ultra wideband radar cross Section (RCS) Reduction. The proposed polarization conversion metasurface consists of double-heads arrow unit cell with its 90°, 180° and 270° rotated ones to create the destructive interferences cancellation and radar cross Section (RCS) Reduction, consequently. The proposed metasurface demonstrates ultra-wide band 10-dB RCS Reduction from 9 to 40 GHz (126.5%) for normally TM- and TE- polarized incident waves. The good agreement between the simulation and measurement results at 0°, 20° and 40° incident angles prove the idea, also. The ultra wideband RCS Reduction of the proposed metasurface as well as its low profile, light weight and low cost prove its high capability compared with the state of the art references.
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Wide band radar cross Section Reduction by thin AMC structure
AEU - International Journal of Electronics and Communications, 2018Co-Authors: Edris Ameri, Seyed Hassan Esmaeli, Seyed Hassan SedighyAbstract:Abstract A new thin and wideband RCS Reduction metasurface is designed and fabricated by using two different AMC unit cell tiles arranged in chessboard like configuration. One of these tiles is formed by saltire arrow unit cells, whereas the other one is formed by Jerusalem unit cells which are designed to achieve out phase difference at broad frequency range. This metasurface reduces the RCS more than 10-dB from 15.75 GHz to 41.3 GHz (90% bandwidth). The designed metasurface works properly at both TE and TM propagation modes, also. Moreover, it has stable 10-dB RCS Reduction bandwidth for TM propagation mode up to 50° oblique incident angle and 30° for TE ones. These good specifications prove the designed metasurface capability compared with the state of the art references.
P De Maagt - One of the best experts on this subject based on the ideXlab platform.
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broadband radar cross Section Reduction using amc technology
IEEE Transactions on Antennas and Propagation, 2013Co-Authors: Juan Carlos Iriarte Galarregui, I Ederra, Ramon Gonzalo, Amagoia Tellechea Pereda, Jose Luis Martinez De Falcon, P De MaagtAbstract:This paper presents the design, fabrication, and characterization of a planar broadband chessboard structure to reduce the radar cross-Section (RCS) of an object. The chessboard -like configuration is formed by combining two artificial magnetic conductor (AMC) cells. The bandwidth limitations intrinsic to AMC structures are overcome in this work by properly selecting the phase slope versus frequency of both AMC structures. A 180 ° phase difference has been obtained over more than 40% frequency bandwidth with a RCS Reduction larger than 10 dB. The influence of the incidence angle in the working bandwidth has been performed. A good agreement between simulations and measurements is achieved.
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thin amc structure for radar cross Section Reduction
IEEE Transactions on Antennas and Propagation, 2007Co-Authors: M Paquay, J C Iriarte, I Ederra, Ramon Gonzalo, P De MaagtAbstract:A thin artificial magnetic conductor (AMC) structure is designed and breadboarded for radar cross-Section (RCS) Reduction applications. The design presented in this paper shows the advantage of geometrical simplicity while simultaneously reducing the overall thickness (for the current design ). The design is very pragmatic and is based on a combination of AMC and perfect electric conductor (PEC) cells in a chessboard like configuration. An array of Sievenpiper's mushrooms constitutes the AMC part, while the PEC part is formed by full metallic patches. Around the operational frequency of the AMC-elements, the reflection of the AMC and PEC have opposite phase, so for any normal incident plane wave the reflections cancel out, thus reducing the RCS. The same applies to specular reflections for off-normal incidence angles. A simple basic model has been implemented in order to verify the behavior of this structure, while Ansoft-HFSS software has been used to provide a more thorough analysis. Both bistatic and monostatic measurements have been performed to validate the approach.
Anxue Zhang - One of the best experts on this subject based on the ideXlab platform.
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Radar cross Section Reduction metasurface based on random phase gradients
Applied Physics B, 2018Co-Authors: Guoxiang Dong, Anxue Zhang, Shitao Zhu, Song Xia, Xiaoyong WeiAbstract:In this paper, we design a novelty metasurface for achieving radar cross Section (RCS) Reduction. The proposed metasurface can achieve phase difference by rotating its unit cells to different rotating angles as traditional Pancharatnam–Berry (P–B) phase. However, compared with traditional P–B phase metasurface, the unit cells of this proposed metasurface do not possess certain period, it indicates that random phase gradients can easily produce on this proposed metasurface. The direction and the scalar of these produced random phase gradients are all random, and the incident waves can be diffused by these random phase gradients, realizing wideband, wide angle, polarization-independent RCS Reduction. The design of units without fixed period increases the freedom of controlling electromagnetic wave. Both the simulation and experiment show that the proposed metasurface is valuable for stealth technology.
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Novel Microstrip Antenna Array with wideband Radar Cross Section Reduction
2018 12th International Symposium on Antennas Propagation and EM Theory (ISAPE), 2018Co-Authors: Chunhui Mou, Anxue Zhang, Shuxi GongAbstract:A novel microstrip antenna array with reduced radar cross Section (RCS) is presented in this paper by shaping the edges of the patch and using probe loading technology. The RCS of the proposed antenna array is significantly reduced between 4GHz and 13GHz under the condition that the incident wave is in grazing angle. The radiation characteristics of the proposed antenna array are well preserved compared with the reference antenna array, which implies the validity of this new RCS Reduction method.
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phase random metasurfaces for broadband wide angle radar cross Section Reduction
Microwave and Optical Technology Letters, 2015Co-Authors: Yang Shen, Jiafu Wang, Yongqiang Pang, Zhibin Pei, Anxue ZhangAbstract:Ultrathin phase random metasurfaces (PRMSs) for reducing radar cross Section (RCS) over a wide range of frequencies and incident angles are presented. The PRMSs are formed by arraying disk-shaped metal patches of random sizes on an ultrathin grounded dielectric layer. The electromagnetic wave incident on the PRMS feels a rough surface due to the random phase value of each inclusion. The energy is then redirected irregularly and thus the backward RCS Reduction in the specular direction can be achieved. The bandwidth of RCS Reduction can be broadened by expanding the distribution interval of the metal patch sizes. The experimental validation is performed and the measured result shows an acceptable agreement with the corresponding simulation. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:2813–2819, 2015
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Phase random metasurfaces for broadband wide‐angle radar cross Section Reduction
Microwave and Optical Technology Letters, 2015Co-Authors: Yang Shen, Jiafu Wang, Yongqiang Pang, Zhibin Pei, Anxue ZhangAbstract:Ultrathin phase random metasurfaces (PRMSs) for reducing radar cross Section (RCS) over a wide range of frequencies and incident angles are presented. The PRMSs are formed by arraying disk-shaped metal patches of random sizes on an ultrathin grounded dielectric layer. The electromagnetic wave incident on the PRMS feels a rough surface due to the random phase value of each inclusion. The energy is then redirected irregularly and thus the backward RCS Reduction in the specular direction can be achieved. The bandwidth of RCS Reduction can be broadened by expanding the distribution interval of the metal patch sizes. The experimental validation is performed and the measured result shows an acceptable agreement with the corresponding simulation. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:2813–2819, 2015
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wideband radar cross Section Reduction using two dimensional phase gradient metasurfaces
Applied Physics Letters, 2014Co-Authors: Jieqiu Zhang, Jiafu Wang, Hongya Chen, Anxue ZhangAbstract:Phase gradient metasurface (PGMs) are artificial surfaces that can provide pre-defined in-plane wave-vectors to manipulate the directions of refracted/reflected waves. In this Letter, we propose to achieve wideband radar cross Section (RCS) Reduction using two-dimensional (2D) PGMs. A 2D PGM was designed using a square combination of 49 split-ring sub-unit cells. The PGM can provide additional wave-vectors along the two in-plane directions simultaneously, leading to either surface wave conversion, deflected reflection, or diffuse reflection. Both the simulation and experiment results verified the wide-band, polarization-independent, high-efficiency RCS Reduction induced by the 2D PGM.
Seyed Hassan Esmaeli - One of the best experts on this subject based on the ideXlab platform.
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Ultra-Wideband radar cross Section Reduction by thin AMC metasurface
2020Co-Authors: Seyed Hassan Esmaeli, Edris Ameri, Seyyed Hassan SedighyAbstract:An ultra-wideband thin metasurface is designed and fabricated to reduce the radar cross-Section (RCS) from 9.72 GHz to 26.77 GHz (93 % bandwidth) more than 10 dB. The proposed metasurface is composed of two different artificial magnetic conductor (AMC) tiles with about 180° reflection phase differences to destruct the reflected wave over ultra-wideband frequency. Although the designed tiles have similar unit cell configuration, their reflected phase responses are properly tuned by changing the dimensions. The comparison between the proposed AMC metasurface and some sate of the art references clearly proves the high RCS Reduction bandwidth with very low thickness of the designed AMC metasurface rather than the references. The measured results are in good agreement with the simulation ones which prove the idea.
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Ultra Wideband Radar Cross Section Reduction by Using Polarization Conversion Metasurfaces
Scientific reports, 2019Co-Authors: Edris Ameri, Seyed Hassan Esmaeli, Seyed Hassan SedighyAbstract:In this paper, a polarization conversion metasurface (PCM) is designed for ultra wideband radar cross Section (RCS) Reduction. The proposed polarization conversion metasurface consists of double-heads arrow unit cell with its 90°, 180° and 270° rotated ones to create the destructive interferences cancellation and radar cross Section (RCS) Reduction, consequently. The proposed metasurface demonstrates ultra-wide band 10-dB RCS Reduction from 9 to 40 GHz (126.5%) for normally TM- and TE- polarized incident waves. The good agreement between the simulation and measurement results at 0°, 20° and 40° incident angles prove the idea, also. The ultra wideband RCS Reduction of the proposed metasurface as well as its low profile, light weight and low cost prove its high capability compared with the state of the art references.
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Wide band radar cross Section Reduction by thin AMC structure
AEU - International Journal of Electronics and Communications, 2018Co-Authors: Edris Ameri, Seyed Hassan Esmaeli, Seyed Hassan SedighyAbstract:Abstract A new thin and wideband RCS Reduction metasurface is designed and fabricated by using two different AMC unit cell tiles arranged in chessboard like configuration. One of these tiles is formed by saltire arrow unit cells, whereas the other one is formed by Jerusalem unit cells which are designed to achieve out phase difference at broad frequency range. This metasurface reduces the RCS more than 10-dB from 15.75 GHz to 41.3 GHz (90% bandwidth). The designed metasurface works properly at both TE and TM propagation modes, also. Moreover, it has stable 10-dB RCS Reduction bandwidth for TM propagation mode up to 50° oblique incident angle and 30° for TE ones. These good specifications prove the designed metasurface capability compared with the state of the art references.
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Wideband radar cross-Section Reduction by AMC
Electronics Letters, 2016Co-Authors: Seyed Hassan Esmaeli, Seyed Hassan SedighyAbstract:A new planar wideband chessboard structure is designed to reduce the radar cross-Section (RCS) of an object. This proposed chessboard configuration is composed of two different artificial magnetic conductor (AMC) tiles. One of these tiles is formed by saltire arrow unit cells, whereas the other one is formed by four E-shaped ones. A 180° ± 30° phase difference between these tiles achieved by precise design of the AMC unit cells of more than 9.4–23.28 GHz (85%) reduces the RCS by more than 10 dB. The fabricated board results show very good agreement with the simulated ones, which verify the ability and capability of the proposed structure.
