In this paper, a linear-to-circular polarization converter using a three-layer frequency selective surface based on Ishaped circular structure resonant is presented and investigated. Numerical simulations exhibit that...In this paper, a linear-to-circular polarization converter using a three-layer frequency selective surface based on Ishaped circular structure resonant is presented and investigated. Numerical simulations exhibit that when the normal ypolarized waves impinge on this device propagating towards ＋z direction, the two orthogonal components of the transmitted waves have a 90° phase difference as well as the nearly equal amplitudes at the resonant frequency of 7.04 GHz, which means that the left-hand circular polarization is realized in transmission. For validating the proposed design, a prototype which consists of 25 × 25 elements has been designed, manufactured and measured. The measured results are in good agreement with the simulated ones, showing that the polarization conversion transmission is over-3 dB in the frequency range of 5.22–8.08 GHz and the axial ratio is below 3 dB from 5.86 GHz to 7.34 GHz.展开更多
This paper investigates the frequency-selective property of a planar layer consisting of period arrays both theoretically and experimentally for different polarizations at arbitrary incident angle. The novel element i...This paper investigates the frequency-selective property of a planar layer consisting of period arrays both theoretically and experimentally for different polarizations at arbitrary incident angle. The novel element is designed by loading the rectangular microstrip element with L-shaped conducting patch at its two ends. Based on the spectral-domain method, the frequency response including angle effect and polarization effect of the frequency selective surface （FSS） structure are analysed and the plots of the frequency versus transmission coefficient are obtained. As a result of the numerical analysis, it is shown that if the source polarization is changed, polarization-independence of previous FSS design can be achieved only for normal incidence, which limits most FSS applications. But in our proposed structure, the better polarization-independency for arbitrary incident angle can be achieved. It is observed that the simulated result comes very close to the experimental result.展开更多
A band-pass frequency selective surface(FSS) with polarization rotation property is proposed. The proposed polarization rotating FSS(PR-FSS) is a two-dimensional periodic structure, its unit cell is an antenna-filter-...A band-pass frequency selective surface(FSS) with polarization rotation property is proposed. The proposed polarization rotating FSS(PR-FSS) is a two-dimensional periodic structure, its unit cell is an antenna-filter-antenna(AFA) module,and the polarization directions of the upper and lower antennas in each AFA module are orthogonal to each other, so the PR-FSS can achieve frequency selection and 90 degrees polarization rotation at the same time. The numerical simulation demonstrate that the anticipated frequency selection and polarization rotation are realized by the PR-FSS in the frequency band from 8.84 GHz to 10.30 GHz with a relative bandwidth of 15.26%, and the maximum insertion loss in the pass band is only 0.17 d B. Finally, one effective experiment validation is carried out, a reasonable agreement is observed between the experimental and simulated results except for a slight deviation caused by fabrication error and measurement tolerance.展开更多
In order to realize the tunable performance of a frequency selective surface （FSS）, a new unit cell is designed in this paper by properly adding two metal shorts to the ring slot. Based on the spectral-domain method...In order to realize the tunable performance of a frequency selective surface （FSS）, a new unit cell is designed in this paper by properly adding two metal shorts to the ring slot. Based on the spectral-domain method, the frequency responses of the FSS structure with two shorts per slot ring are analysed for both the horizontal and the vertical polarizations at the normal incidence. It is demonstrated that the presence of the metal shorts does not affect the resonant frequency of the horizontally polarized wave but doubles the resonant frequency of the vertically polarized wave. Therefore based on the analysis of the novel transmission properties, a new approach to adjusting the resonant frequency by rotating the FSS screen 90° is presented in this paper.展开更多
A frequency selective polarization rotator that can rotate the polarization angle of an incident electromagnetic wave at the microwave frequency by 45 is presented. The polarization rotator is based on a two-dimension...A frequency selective polarization rotator that can rotate the polarization angle of an incident electromagnetic wave at the microwave frequency by 45 is presented. The polarization rotator is based on a two-dimensional periodic array of substrate integrated waveguide cavities, realizing the polarization rotation by coupling the input signal to the output wave through three metallic slots. Two layers of frequency selective surfaces are cascaded by substrate and form the polarization rotator. A vertical slot on the top layer is used to select the horizontal polarization from the incident wave, the vertical and the horizontal slots on the bottom layer are, respectively, used to obtain horizontally and vertically polarized outgoing waves. The two orthogonal outgoing waves are combined to result in the 45~ polarized wave. Both full wave simulation and experimental measurement are carried out, together validating the proposed method.展开更多
A thick-screen frequency selective surface （FSS） has not only a broad bandwidth but also the advantages of overcoming the multilayer FSS shortcoming of complex structure and low transmittance of centre frequency due...A thick-screen frequency selective surface （FSS） has not only a broad bandwidth but also the advantages of overcoming the multilayer FSS shortcoming of complex structure and low transmittance of centre frequency due to the cascade of FSSs, and this means it could potentially be applied in a stealth curved streamlined radome. However, there is an unsteadiness of centre frequency in a wide range of incident angles and another unsteadiness of polarization in a big incident angle. In order to solve these problems, in this paper we provide a novel four-legged loaded element thick-screen FSS. The structure is analysed and simulated using the mode matching method and moment method. The centre frequency, the transmittance of centre frequency, and bandwidth of the structure are investigated when some parameters including the polarization at a big incident angle and the incident angles of TE ＆： TM waves are changed. The novel four-legged loaded element thick-screen FSS has better transmission properties with a better steadiness of polarization and incident angle independence. The novel structure of the four-legged loaded element thick-screen FSS provides a valuable reference for their application in a stealth curved streamlined radome.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61471387,61271250,and 61571460)
文摘In this paper, a linear-to-circular polarization converter using a three-layer frequency selective surface based on Ishaped circular structure resonant is presented and investigated. Numerical simulations exhibit that when the normal ypolarized waves impinge on this device propagating towards ＋z direction, the two orthogonal components of the transmitted waves have a 90° phase difference as well as the nearly equal amplitudes at the resonant frequency of 7.04 GHz, which means that the left-hand circular polarization is realized in transmission. For validating the proposed design, a prototype which consists of 25 × 25 elements has been designed, manufactured and measured. The measured results are in good agreement with the simulated ones, showing that the polarization conversion transmission is over-3 dB in the frequency range of 5.22–8.08 GHz and the axial ratio is below 3 dB from 5.86 GHz to 7.34 GHz.
基金supported by the National Defense Innovation Foundation of Chinese Academy of Sciences (Grant No CXJJ-149)
文摘This paper investigates the frequency-selective property of a planar layer consisting of period arrays both theoretically and experimentally for different polarizations at arbitrary incident angle. The novel element is designed by loading the rectangular microstrip element with L-shaped conducting patch at its two ends. Based on the spectral-domain method, the frequency response including angle effect and polarization effect of the frequency selective surface （FSS） structure are analysed and the plots of the frequency versus transmission coefficient are obtained. As a result of the numerical analysis, it is shown that if the source polarization is changed, polarization-independence of previous FSS design can be achieved only for normal incidence, which limits most FSS applications. But in our proposed structure, the better polarization-independency for arbitrary incident angle can be achieved. It is observed that the simulated result comes very close to the experimental result.
基金supported by the National Natural Science Foundation of China (Grant No. 62072378)Xi’an Science and Technology Plan Project, China (Grant No. GXYD20.4)。
文摘A band-pass frequency selective surface(FSS) with polarization rotation property is proposed. The proposed polarization rotating FSS(PR-FSS) is a two-dimensional periodic structure, its unit cell is an antenna-filter-antenna(AFA) module,and the polarization directions of the upper and lower antennas in each AFA module are orthogonal to each other, so the PR-FSS can achieve frequency selection and 90 degrees polarization rotation at the same time. The numerical simulation demonstrate that the anticipated frequency selection and polarization rotation are realized by the PR-FSS in the frequency band from 8.84 GHz to 10.30 GHz with a relative bandwidth of 15.26%, and the maximum insertion loss in the pass band is only 0.17 d B. Finally, one effective experiment validation is carried out, a reasonable agreement is observed between the experimental and simulated results except for a slight deviation caused by fabrication error and measurement tolerance.
基金Project supported by the National Natural Science Foundation of China (Grant No. 61172012)
文摘In order to realize the tunable performance of a frequency selective surface （FSS）, a new unit cell is designed in this paper by properly adding two metal shorts to the ring slot. Based on the spectral-domain method, the frequency responses of the FSS structure with two shorts per slot ring are analysed for both the horizontal and the vertical polarizations at the normal incidence. It is demonstrated that the presence of the metal shorts does not affect the resonant frequency of the horizontally polarized wave but doubles the resonant frequency of the vertically polarized wave. Therefore based on the analysis of the novel transmission properties, a new approach to adjusting the resonant frequency by rotating the FSS screen 90° is presented in this paper.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.60990322,60990320,60801001,and 61101011)the Key Grant Project of Ministry of Education of China(Grant No.313029)+1 种基金the Ph.D.Program Foundation of Ministry of Education of China(Grant Nos.20100091110036 and 20120091110032)the Jiangsu Key Laboratory of Advanced Techniques for Manipulating Electromagnetic Waves,China
文摘A frequency selective polarization rotator that can rotate the polarization angle of an incident electromagnetic wave at the microwave frequency by 45 is presented. The polarization rotator is based on a two-dimensional periodic array of substrate integrated waveguide cavities, realizing the polarization rotation by coupling the input signal to the output wave through three metallic slots. Two layers of frequency selective surfaces are cascaded by substrate and form the polarization rotator. A vertical slot on the top layer is used to select the horizontal polarization from the incident wave, the vertical and the horizontal slots on the bottom layer are, respectively, used to obtain horizontally and vertically polarized outgoing waves. The two orthogonal outgoing waves are combined to result in the 45~ polarized wave. Both full wave simulation and experimental measurement are carried out, together validating the proposed method.
文摘A thick-screen frequency selective surface （FSS） has not only a broad bandwidth but also the advantages of overcoming the multilayer FSS shortcoming of complex structure and low transmittance of centre frequency due to the cascade of FSSs, and this means it could potentially be applied in a stealth curved streamlined radome. However, there is an unsteadiness of centre frequency in a wide range of incident angles and another unsteadiness of polarization in a big incident angle. In order to solve these problems, in this paper we provide a novel four-legged loaded element thick-screen FSS. The structure is analysed and simulated using the mode matching method and moment method. The centre frequency, the transmittance of centre frequency, and bandwidth of the structure are investigated when some parameters including the polarization at a big incident angle and the incident angles of TE ＆： TM waves are changed. The novel four-legged loaded element thick-screen FSS has better transmission properties with a better steadiness of polarization and incident angle independence. The novel structure of the four-legged loaded element thick-screen FSS provides a valuable reference for their application in a stealth curved streamlined radome.
