Circularly polarized (CP) lens antenna has been applied to numerous wireless communication systems based on its unique advantages such as high antenna gain, low manufacturing cost, especially stable data transmissio...Circularly polarized (CP) lens antenna has been applied to numerous wireless communication systems based on its unique advantages such as high antenna gain, low manufacturing cost, especially stable data transmission between the transmitter and the receiver. Unfortunately, current available CP lens antennas mostly suffer from high profile, low aperture efficiency as well as complex design. In this paper, we propose an ultra-thin CP lens antenna based on the designed single- layered Pancharatnam-Berry (PB) transparent metasurface with focusing property. The PB metasurface exhibits a high transmissivity, which ensures a high efficiency of the focusing property. Launched the metasurface with a CP patch antenna at its focal point, a low-profile lens antenna is simulated and measured. The experimental results show that our lens antenna exhibits a series of advantages including high radiation gain of 20.7 dB, aperture efficiency better than 41.3%, and also narrow half power beam width (HPBW) of 13°at about 14GHz. Our finding opens a door to realize ultra-thin transparent metasurface with other functionalities or at other working frequencies.展开更多
A new method to design an ultra-thin high-gain circularly-polarized antenna system with high efficiency is proposed based on the geometrical phase gradient metasurface(GPGM).With an accuracy control of the transmiss...A new method to design an ultra-thin high-gain circularly-polarized antenna system with high efficiency is proposed based on the geometrical phase gradient metasurface(GPGM).With an accuracy control of the transmission phase and also the high transmission amplitude,the GPGM is capable of manipulating an electromagnetic wave arbitrarily.A focusing transmission lens working at Ku band is well optimized with the F /D of 0.32.A good focusing effect is demonstrated clearly by theoretical calculation and electromagnetic simulation.For further application,an ultra-thin single-layer transmissive lens antenna based on the proposed focusing metasurface operating at 13 GHz is implemented and launched by an original patch antenna from the perspective of high integration,simple structure,and low cost.Numerical and experimental results coincide well,indicating the advantages of the antenna system,such as a high gain of 17.6 d B,the axis ratio better than 2 d B,a high aperture efficiency of 41%,and also a simple fabrication process based on the convenient print circuit board technology.The good performance of the proposed antenna indicates promising applications in portable communication systems.展开更多
We propose a dual-polarized lens antenna system based on isotropic metasurfaces for 12 GHz applications. The metasurface lens is composed of subwavelength unit cells(0.24λ0) with metallic strips etched on the top a...We propose a dual-polarized lens antenna system based on isotropic metasurfaces for 12 GHz applications. The metasurface lens is composed of subwavelength unit cells(0.24λ0) with metallic strips etched on the top and bottom sides of the unit cell, and a cross-slots metallic layer in the middle that serves as the ground. The multimode resonance in the unit cell can realize a large phase shift(covering 0?–360?), and the total transmission efficiency of the lens is above 80%.The feed antenna at the focal point of the lens is a broadband dual-polarized microstrip antenna. Both the simulated and the measured results demonstrate that the dual-polarized lens antenna system can realize a gain of more than 16.1 dB, and an input port isolation of more than 25.0 dB.展开更多
Rotman lens,which is a radio frequency beam-former that consists of multiple input and multiple output beam ports,can be used in industrial,scientific,and medical applications as a beam steering device.The input ports...Rotman lens,which is a radio frequency beam-former that consists of multiple input and multiple output beam ports,can be used in industrial,scientific,and medical applications as a beam steering device.The input ports collect the signals to be propagated through the lens cavity toward the output ports before being transmitted by the antenna arrays to the destination in order to enhance the error performance by optimizing the overall signal to noise ratio(SNR).In this article,a low-cost Rotman lens antenna is designed and deployed to enhance the overall performance of the conventional cooperative communication systems without needing any additional power,extra time or frequency slots.In the suggested system,the smart Rotman lens antennas generate a beam steering in the direction of the destination to maximize the received SNR at the destination by applying the proposed optimal beamforming technique.The suggested optimal beamforming technique enjoys high diversity,as well as,low encoding and decoding complexity.Furthermore,we proved the advantages of our suggested strategy through both theoretical results and simulations using Monte Carlo runs.The Monte Carlo simulations show that the suggested strategy enjoys better error performance compared to the current state-of-the-art distributed multiantenna strategies.In addition,the bit error rate(BER)curves drawn from the analytical results are closely matching to those drawn from our conducted Monte Carlo simulations.展开更多
An isotropic electromagnetic (EM) lens based on Huygens' metasurface is proposed for 28.0 GHz lens antenna design. The lens consists of a series of non-resonant and subwavelength metallic patterns etched on both si...An isotropic electromagnetic (EM) lens based on Huygens' metasurface is proposed for 28.0 GHz lens antenna design. The lens consists of a series of non-resonant and subwavelength metallic patterns etched on both sides of an ultrathin dielectric substrate. Both electric and magnetic responses are introduced to realize desired abrupt phase change and high-efficiency transmission for the secondary wavelets in the incident wavefront. Then, a substrate-integrated waveguide (SIW) fed patch antenna is combined with the lens as the primary feed to form a low-profile lens antenna system. The simulated and measured results coincide with each other, and demonstrate that the prototype realizes 8.8 dB-12.6 dB gain increment and low side-lobe levels over the bandwidth of 26.7 GHz-30.0 GHz. The novel design leads to a low-profile, light weight, and low-cost antenna solution in a wireless communication system.展开更多
A new aspheric surface pre-collimation lenses system for the optical antenna of three-dimensional (3D) imaging of lidar has been optimally designed and simulated by optical design software CODE-V.Four kinds of asphe...A new aspheric surface pre-collimation lenses system for the optical antenna of three-dimensional (3D) imaging of lidar has been optimally designed and simulated by optical design software CODE-V.Four kinds of aspheric surfaces spherical lenses including the sections of spherical,elliptical,hyperbola,and parabola have been researched.The optical system,including the elliptical cylinder lenses collimation and the optical antenna,can be realized less than 5 rad collimation angle for dot source semiconductor laser beam.展开更多
According to the aplanatism theory, lens can be used to focus the electromagnetic wave. A piano-convex hyperboloid of revo- lution lens made of low loss material is designed for combinatorial applications with the rec...According to the aplanatism theory, lens can be used to focus the electromagnetic wave. A piano-convex hyperboloid of revo- lution lens made of low loss material is designed for combinatorial applications with the rectangle microstrip applicator in microwave hyperthermia. Results of the extensive simulations and experiments show that the introduction of the lens to the clinical used antenna can significantly improve the directivity and hence increase the microwave power density in near field. In microwave hyperthermia applications, the lens antenna will exhibit superior directivity, high gain and well thermal efficiency for tumor in superficial layer. Besides, it has small treatment area that is helpful for reducing the injury of the normal tissue around the tumor.展开更多
The two-dimensional(2D) compound parabolic concentrator's(CPC) characteristics are analyzed.It is shown that CPC's height is taller and its light collecting ability is stronger with the CPC's field of view decr...The two-dimensional(2D) compound parabolic concentrator's(CPC) characteristics are analyzed.It is shown that CPC's height is taller and its light collecting ability is stronger with the CPC's field of view decreasing when the bottom radius is unchanged.According to the ZEMAX analysis,CPC is good at collecting optical signal,and the antenna combining CPC with hemispherical lens can gather more optical signal than a single CPC or CPCs combined in series.The light propagation of scattering optical communication based on multiple scattering is simulated by Monte Carlo method,and the results show that using CPC as receiving antenna can strengthen communication system's signal collecting ability and increase its communication distance.展开更多
Orbital angular momentum(OAM)based radio vortex wireless communications have received much attention recently because it can significantly increase the spectrum efficiency.The uniform circular array(UCA)is a simple an...Orbital angular momentum(OAM)based radio vortex wireless communications have received much attention recently because it can significantly increase the spectrum efficiency.The uniform circular array(UCA)is a simple antenna structure for high spectrum efficiency radio vortex wireless communications.How-ever,the OAM based electromagnetic waves are vortically hollow and divergent,which may result in the signal loss.Moreover,the divergence of corresponding OAM based electromagnetic wave increases as the order of OAM-mode increases.Therefore,it is difficult to use high-order OAM-mode,because the corresponding received signal-to-noise ratio(SNR)is very small.To overcome the difficulty of high-order OAM modes transmission,in this paper we propose a lens antenna based electromagnetic waves converging scheme,which maintains the angular identification of multiple OAM-modes for radio vortex wireless communications.We further develop a bifocal lens antenna to not only converge the electromagnetic wave,but also compensate the SNR loss on traditional electromagnetic waves.Simulation results show that the proposed bifocal lens can converge the OAM waves into cylinder-like beams,providing an efficient way to in-crease the spectrum efficiency of wireless communications.展开更多
In this review article, a brief introduction on the theory, experiments and applications of metamaterials is presented. The main focuses are concentrated on the composing meta-atoms, the method of transformation optic...In this review article, a brief introduction on the theory, experiments and applications of metamaterials is presented. The main focuses are concentrated on the composing meta-atoms, the method of transformation optics, the experimental demonstration of negative refraction, and the realizations of invisibility cloaks and electromagnetic black hole. At the end of this review, some typical applications of metamaterials, including high-performance antennas made of zero-refractive-index materials, inhomogeneous metamaterial lenses, and planar metasurfaces, are introduced in details.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.61372034)
文摘Circularly polarized (CP) lens antenna has been applied to numerous wireless communication systems based on its unique advantages such as high antenna gain, low manufacturing cost, especially stable data transmission between the transmitter and the receiver. Unfortunately, current available CP lens antennas mostly suffer from high profile, low aperture efficiency as well as complex design. In this paper, we propose an ultra-thin CP lens antenna based on the designed single- layered Pancharatnam-Berry (PB) transparent metasurface with focusing property. The PB metasurface exhibits a high transmissivity, which ensures a high efficiency of the focusing property. Launched the metasurface with a CP patch antenna at its focal point, a low-profile lens antenna is simulated and measured. The experimental results show that our lens antenna exhibits a series of advantages including high radiation gain of 20.7 dB, aperture efficiency better than 41.3%, and also narrow half power beam width (HPBW) of 13°at about 14GHz. Our finding opens a door to realize ultra-thin transparent metasurface with other functionalities or at other working frequencies.
基金Project supported by the National Natural Science Foundation of China(Grant No.61372034)
文摘A new method to design an ultra-thin high-gain circularly-polarized antenna system with high efficiency is proposed based on the geometrical phase gradient metasurface(GPGM).With an accuracy control of the transmission phase and also the high transmission amplitude,the GPGM is capable of manipulating an electromagnetic wave arbitrarily.A focusing transmission lens working at Ku band is well optimized with the F /D of 0.32.A good focusing effect is demonstrated clearly by theoretical calculation and electromagnetic simulation.For further application,an ultra-thin single-layer transmissive lens antenna based on the proposed focusing metasurface operating at 13 GHz is implemented and launched by an original patch antenna from the perspective of high integration,simple structure,and low cost.Numerical and experimental results coincide well,indicating the advantages of the antenna system,such as a high gain of 17.6 d B,the axis ratio better than 2 d B,a high aperture efficiency of 41%,and also a simple fabrication process based on the convenient print circuit board technology.The good performance of the proposed antenna indicates promising applications in portable communication systems.
基金Project supported by the Open Research Program of the State Key Laboratory of Millimeter Waves,China(Grant No.K201926)the Postgraduate Research&Practice Innovation Program of Jiangsu Province,Chinathe Nanjing University of Posts and Telecommunications Scientific Foundation,China(Grant No.NY215137)
文摘We propose a dual-polarized lens antenna system based on isotropic metasurfaces for 12 GHz applications. The metasurface lens is composed of subwavelength unit cells(0.24λ0) with metallic strips etched on the top and bottom sides of the unit cell, and a cross-slots metallic layer in the middle that serves as the ground. The multimode resonance in the unit cell can realize a large phase shift(covering 0?–360?), and the total transmission efficiency of the lens is above 80%.The feed antenna at the focal point of the lens is a broadband dual-polarized microstrip antenna. Both the simulated and the measured results demonstrate that the dual-polarized lens antenna system can realize a gain of more than 16.1 dB, and an input port isolation of more than 25.0 dB.
基金The article has been supported by the College of Engineering and Technology,American University of the Middle East,Kuwait.Homepage:https://www.aum.edu.kw.
文摘Rotman lens,which is a radio frequency beam-former that consists of multiple input and multiple output beam ports,can be used in industrial,scientific,and medical applications as a beam steering device.The input ports collect the signals to be propagated through the lens cavity toward the output ports before being transmitted by the antenna arrays to the destination in order to enhance the error performance by optimizing the overall signal to noise ratio(SNR).In this article,a low-cost Rotman lens antenna is designed and deployed to enhance the overall performance of the conventional cooperative communication systems without needing any additional power,extra time or frequency slots.In the suggested system,the smart Rotman lens antennas generate a beam steering in the direction of the destination to maximize the received SNR at the destination by applying the proposed optimal beamforming technique.The suggested optimal beamforming technique enjoys high diversity,as well as,low encoding and decoding complexity.Furthermore,we proved the advantages of our suggested strategy through both theoretical results and simulations using Monte Carlo runs.The Monte Carlo simulations show that the suggested strategy enjoys better error performance compared to the current state-of-the-art distributed multiantenna strategies.In addition,the bit error rate(BER)curves drawn from the analytical results are closely matching to those drawn from our conducted Monte Carlo simulations.
基金supported by the National Natural Science Foundation of China (61401229)the Science and Technology Project of Jiangsu Province (BE2015002-2)+1 种基金the Open Research Program of the State Key Laboratory of Millimeter Waves (K201616)the Nanjing University of Posts and Telecommunications Scientific Foundation (NY215137)
文摘An isotropic electromagnetic (EM) lens based on Huygens' metasurface is proposed for 28.0 GHz lens antenna design. The lens consists of a series of non-resonant and subwavelength metallic patterns etched on both sides of an ultrathin dielectric substrate. Both electric and magnetic responses are introduced to realize desired abrupt phase change and high-efficiency transmission for the secondary wavelets in the incident wavefront. Then, a substrate-integrated waveguide (SIW) fed patch antenna is combined with the lens as the primary feed to form a low-profile lens antenna system. The simulated and measured results coincide with each other, and demonstrate that the prototype realizes 8.8 dB-12.6 dB gain increment and low side-lobe levels over the bandwidth of 26.7 GHz-30.0 GHz. The novel design leads to a low-profile, light weight, and low-cost antenna solution in a wireless communication system.
基金supported by Pre-research Foundation under Grant No. G020104PJ09DZ0246the National Natural Science Foundation of China under Grant No. 11004024
文摘A new aspheric surface pre-collimation lenses system for the optical antenna of three-dimensional (3D) imaging of lidar has been optimally designed and simulated by optical design software CODE-V.Four kinds of aspheric surfaces spherical lenses including the sections of spherical,elliptical,hyperbola,and parabola have been researched.The optical system,including the elliptical cylinder lenses collimation and the optical antenna,can be realized less than 5 rad collimation angle for dot source semiconductor laser beam.
文摘According to the aplanatism theory, lens can be used to focus the electromagnetic wave. A piano-convex hyperboloid of revo- lution lens made of low loss material is designed for combinatorial applications with the rectangle microstrip applicator in microwave hyperthermia. Results of the extensive simulations and experiments show that the introduction of the lens to the clinical used antenna can significantly improve the directivity and hence increase the microwave power density in near field. In microwave hyperthermia applications, the lens antenna will exhibit superior directivity, high gain and well thermal efficiency for tumor in superficial layer. Besides, it has small treatment area that is helpful for reducing the injury of the normal tissue around the tumor.
基金supported by the National Natural Science Foundation of China under Grant No.60607013.
文摘The two-dimensional(2D) compound parabolic concentrator's(CPC) characteristics are analyzed.It is shown that CPC's height is taller and its light collecting ability is stronger with the CPC's field of view decreasing when the bottom radius is unchanged.According to the ZEMAX analysis,CPC is good at collecting optical signal,and the antenna combining CPC with hemispherical lens can gather more optical signal than a single CPC or CPCs combined in series.The light propagation of scattering optical communication based on multiple scattering is simulated by Monte Carlo method,and the results show that using CPC as receiving antenna can strengthen communication system's signal collecting ability and increase its communication distance.
基金supported in part by the National Natural Science Foundation of China(No.61771368)the Young Elite Scientists Sponsorship Program by CAST(2016QRNC001)the Young Talent Support Fund of Science and Technology of Shaanxi Province(2018KJXX-025).
文摘Orbital angular momentum(OAM)based radio vortex wireless communications have received much attention recently because it can significantly increase the spectrum efficiency.The uniform circular array(UCA)is a simple antenna structure for high spectrum efficiency radio vortex wireless communications.How-ever,the OAM based electromagnetic waves are vortically hollow and divergent,which may result in the signal loss.Moreover,the divergence of corresponding OAM based electromagnetic wave increases as the order of OAM-mode increases.Therefore,it is difficult to use high-order OAM-mode,because the corresponding received signal-to-noise ratio(SNR)is very small.To overcome the difficulty of high-order OAM modes transmission,in this paper we propose a lens antenna based electromagnetic waves converging scheme,which maintains the angular identification of multiple OAM-modes for radio vortex wireless communications.We further develop a bifocal lens antenna to not only converge the electromagnetic wave,but also compensate the SNR loss on traditional electromagnetic waves.Simulation results show that the proposed bifocal lens can converge the OAM waves into cylinder-like beams,providing an efficient way to in-crease the spectrum efficiency of wireless communications.
基金supported by the National Natural Science Foundation of China(Grant Nos.61571117,61171024,61171026,61138001,61302018,61401089 and 61522106)the 111 Project(Grant No.111-2-05)+2 种基金the Open Research Funds of State Key Laboratory of Millimeter Waves(Grant No.K201409)the Fundamental Research Funds for the Central Universities(Grant Nos.LZUJBKY-2015-k07,LZUJBKY-2014-43 and LZUJBKY-2014-237)the Foundation of National Excellent Doctoral Dissertation of China
文摘In this review article, a brief introduction on the theory, experiments and applications of metamaterials is presented. The main focuses are concentrated on the composing meta-atoms, the method of transformation optics, the experimental demonstration of negative refraction, and the realizations of invisibility cloaks and electromagnetic black hole. At the end of this review, some typical applications of metamaterials, including high-performance antennas made of zero-refractive-index materials, inhomogeneous metamaterial lenses, and planar metasurfaces, are introduced in details.