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基于场耦合的概念,建立了有源相控阵天线阵面的机电耦合模型。天线阵面的阵元布置为环栅阵,仿真计算了阵面因子方向图和阵面方向图。依据此环栅阵,将结构误差加入机电耦合模型,得到结构变形误差,阵面加工误差,累积安装误差对天线阵面电性能的影响数据。研究分析结构误差对天线增益、栅瓣电平、波束指向和波束宽度等天线阵面电性能指标的影响,可知天线阵面对振动的位移响应对电性能的影响满足系统的指标要求,阵面加工误差和累积安装误差对天线阵面电性能的影响较小。 相似文献
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讨论了一种低折射率人工电磁材料应用于天线阵设计,在口径面积相同的情况下,获得了比传统天线阵更高的方向性。这种阵列天线有如下一些特征:阵元数量显著减少,阵元间距远大于一个波长,馈电网络简单。人工电磁材料由两层周期性的正方形金属网格构成,置于阵元的上方。结果表明:一个由同轴馈电的2′2 微带贴片集成人工电磁材料覆层构成的阵列天线,具有26dB 以上的高方向性,优于传统天线。相同口径面积的情况下,一个4′4 阵元集成人工电磁材料覆层的天线阵结构,其增益与一个传统的16′16 阵元的天线阵结构相当。前者显而易见地具有更简单的馈电网络和较高的天线口径效率。本文提出的天线阵,在高增益天线系统中具有较高的应用价值。 相似文献
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遗传算法在波导裂缝阵列天线设计中的应用 总被引:3,自引:1,他引:2
本文采用遗传算法分两步优化矩形波导裂缝天线阵,首先对天线阵元激励幅值进行了初步优化,直接利用可分离型分布,大大简化了初步设计的过程,并将阵元激励幅值比值作为优化参量以利于波导结构的馈电;在随后进行的波导裂缝阵列阵元的偏置量和缝隙长度的优化上动态处理阵元的互耦并结合Elliott设计思想,采用遗传算法得出的3cm(1×4)缝阵结果验证了GA算法的有效性和准确性,并完成了72元矩形波导裂缝阵列的阵面优化,为大中型阵列优化提供了一种有效的方法. 相似文献
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为解决X波段机载雷达变极化速度较慢的问题,设计了一种可实现脉间变极化的偶极子天线阵.该天线阵采用正交排列薄片电偶极子阵元,并加装垂直贴片和反射板,通过同轴线耦合巴伦进行馈电.利用改造后的阵元组成了一个4×4的16元矩形栅格、矩形边界均匀平面正交极化天线阵,利用射频开关控制馈电线路实现快速变极化,通过高频结构仿真(HFSS)软件对其进行参数优化和建模仿真,结果显示,该天线阵具有较低的驻波比和副瓣电平以及较高的天线增益,可以作为机载正交极化相控阵雷达天线的参考设计,或用作正交极化阵列天线的子阵. 相似文献
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Xiu‐long Bao Xiao‐wei Sun Zheng‐fan Li Wu‐yun Bao Rong Qian 《Journal of Infrared, Millimeter and Terahertz Waves》2004,25(12):1799-1804
The electromagnetic band‐gap (EBG) structure, also called photonic band‐gap structure, consisted by triangular arrays of air columns on the dielectric structure is designed and studied by using the FDTD method. According to the simulated and measured results, the EBG structure effectively suppressing surface wave for TE and TM modes is designed. The optimized EBG structure is presented.The proposed EBG structure is applied to the four‐element microstrip patch array antenna. As results of simulation and measurements, the impedance bandwidth and the gain of proposed EBG patch array antenna are improved. 相似文献
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A Novel Compact Spiral Electromagnetic Band-Gap (EBG) Structure 总被引:1,自引:0,他引:1
Qiu-Rong Zheng Yun-Qi Fu Nai-Chang Yuan 《Antennas and Propagation, IEEE Transactions on》2008,56(6):1656-1660
A novel compact electromagnetic band-gap (EBG) structure in a spiral shape is presented and investigated. This structure significantly enlarges the capacitance between neighboring elements. The simulations and experimental results have proved that the size of the spiral structure is only 30.9% of the conventional EBG structure. Two applications have been shown, including patch antenna with the spiral EBG structure and a double-element microstrip antenna array with low mutual coupling. The measured results show that a gain improvement over 3 dB and a significant reduction of cross polarization in H-plane are obtained. A 6 dB reduction of mutual coupling is achieved in a double-element EBG microstrip antenna array. 相似文献
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Lee Y. Lu X. Hao Y. Yang S. Ubic R. Evans J.R.G. Parini C.G. 《Electronics letters》2007,43(4):195-196
A high directivity millimetre-wave antenna based on woodpile electro-magnetic bandgap (EBG) material at W-band is presented. The woodpile EBG structure is fabricated using the ceramic extrusion freeforming technique with high purity alumina powder. The designed antenna can achieve a narrow beam without using an array. The measured half power beam widths are 14deg and 10deg for E-plane and H-plane, respectively. Measurements results are good compared with simulations 相似文献
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A novel compact electromagnetic-bandgap (EBG) structure and its applications for microwave circuits 总被引:6,自引:0,他引:6
Li Yang Mingyan Fan Fanglu Chen Jingzhao She Zhenghe Feng 《Microwave Theory and Techniques》2005,53(1):183-190
A novel electromagnetic-bandgap (EBG) structure in a fork-like shape is investigated. This structure has an extremely compact size. A comparison has been carried out between the new structure and the conventional mushroom-like EBG structure. Simulations and experimental results have verified that the area of the fork-like structure is less than 40% of the latter. The presented structure also provides an additional degree of freedom to adjust the bandgap position, which is applied to design a novel reconfigurable multiband EBG structure. Several application examples have been demonstrated, including a double-element microstrip antenna array with low mutual coupling, notch-type antenna duplexer, and steerable array with a linearly discrete beamsteering of 20/spl deg/ in steps of 10/spl deg/ at 2.468 GHz. 相似文献
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Weily A.R. Esselle K.P. Bird T.S. Sanders B.C. 《Antennas and Propagation, IEEE Transactions on》2006,54(8):2263-2274
A technique is described for creating linear array antennas that conform to the natural stacking sequence of the woodpile electromagnetic bandgap (EBG) material. Each element in the linear array consists of a woodpile EBG sectoral horn antenna. The electromagnetic confinement mechanism within each horn antenna relies wholly on the 3-D EBG of the woodpile material. The array element has a typical sectoral horn pattern with a directional beam in one principal plane and a broader beam in the other. The bandwidth of the sectoral horn is almost equal to that of the defect EBG waveguide. Measured and theoretical results for radiation patterns, impedance bandwidth and gain of a sectoral horn antenna made from alumina are described, and theoretical results for a design made from silicon are presented. It is shown that the layer-by-layer nature of the woodpile EBG material enables sectoral horn antennas to be easily stacked together in the E-plane to create linear arrays. Analysis of the mutual coupling as a function of element separation and its effect on reflection coefficient are presented for a two-element linear array in silicon. Theoretical analyses for fixed and scanned beam linear arrays of silicon woodpile EBG sectoral horns are described and finite-difference time-domain results are compared with array theory. The fixed beam arrays are designed for high directivity while the scanned beam array enables wide angle beam steering through the use of parasitic array elements. 相似文献
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电磁带隙(EBG)天线是一种可以提高天线辐射口径及增益的新型天线,本文首先以FSS 结构作为EBG 反射面,角
锥喇叭作为辐射源,设计了一种可以工作在29.7-30.2GHz,最大增益为23dB 的EBG 天线;其次,研究了7 个喇叭构成六
边形阵列时的阵列特性;最后,将EBG 天线用作单反射面多波束天线的馈源研究了波束的覆盖特性,结果表明,当波束
大小为1.12°时,多波束天线的峰值增益为44.5dB,边缘交叠电平为40.4dB,载干比大于12dB。证明了这种EBG 天线
具有良好的工作性能,为将来小型化反射面多波束天线的设计提供了一种新的思路。 相似文献
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