小型化Ka波段窄波束天线研究

发布时间：2018-01-01 11:08

本文关键词：小型化Ka波段窄波束天线研究　出处：《电子科技大学》2015年硕士论文　论文类型：学位论文

【摘要】：天线波瓣的大小是雷达特别是预警测绘雷达的重要特性之一。其窄波束、低副瓣能够较大的提高雷达天线的分辨率以及抗干扰能力。对雷达系统的研制有着重要的意义。本论文要研究的内容主要包括:阵列天线中的单元天线选取,Vivaldi天线的设计,天线阵列的排布以及其馈线的研究,反射器天线以及透镜天线结构对阵列天线窄波束化以及小型化的影响。首先说明了天线阵列化是实现天线波瓣窄波束的重要途径,在选取阵列天线的单元天线时,在Ka波段中对比微带贴片天线和Vivaldi天线的特性,同时考虑到阵列天线的馈线问题以及Vivaldi天线波瓣自身的定向性,选择Vivaldi天线作为阵列天线的阵元。在设计Vivaldi天线时,通过经验公式设计Vivaldi天线的槽线、槽线型谐振腔、渐变线等结构,同时再对单个天线的馈线部分进行分析,找出能实现窄波束的Vivaldi天线尺寸。在确定单元天线后,进行阵列天线的组阵研究。将Vivaldi天线看成点源,在不考虑因天线尺寸造成的互藕问题,对其进行圆环阵列仿真。并将实际Vivaldi天线的远场通过矩阵代入阵因子中。得出Vivaldi环形阵列天线的波瓣方向图。再尝试进行激励的等间距阵列仿真,将两种模式进行对比。通过对比,结合实际天线的情况,选择直线阵均匀激励的馈线方式。并对该阵列天线设计功分器设计。在功分器的选择上,对比了威尔金森功分器以及T型公分器。选择了T型功分器对Vivaldi阵列天线进行馈线。在对天线波束进行锐化的途径中,除了阵元分布自身的排列方式,还可以选择其他的方式,引入反射器天线和透镜,尝试使用夹角反射器天线,通过仿真观察其对波束宽度的影响。发现其对波瓣具有一定的约束作用,但是会造成旁瓣过大。通过分析发现,天线后向辐射通过反射器后会反射与前向辐射叠加时两种辐射的相位相近,从而旁瓣增大。进而尝试龙伯透镜天线,发现能使波束变窄,增益增大的特性。根据电磁波在不同介质中的传播特性,建立六面体通孔透镜。同样也具有提高增益,降低波束的作用。最后将这种透镜与Vivaldi阵列天线结合,发现其约束波束的能力有限。通过分析得出透镜在波束宽度为3°左右的情况下,由于增益的提高程度与自身增益比值较小,因此窄波束的能力较小的特点。
[Abstract]:The antenna lobe size is one of the important characteristics of early warning radars especially mapping radar. Its narrow beam, low sidelobe can greatly improve the resolution of radar antenna and anti-jamming ability. Has an important significance for the development of radar system. The research content mainly includes: the unit antenna array in the selection. The design of Vivaldi antenna, antenna array arrangement and its research on feeder, influence of reflector antenna and lens antenna structure of antenna array of narrow beam and miniaturization. The antenna array is an important way to realize the antenna lobe narrow beam antenna, in the selection of antenna array, compared with the characteristic of microstrip patch antenna and the Vivaldi antenna in the Ka band, taking into account the directional feeder of the antenna array and Vivaldi antenna pattern itself, as the array antenna selection Vivaldi The antenna array element. In the design of Vivaldi antenna, slot line through empirical formula design of Vivaldi antenna, slot line resonator, gradient line structure, and then part of a single antenna feeder is analyzed, find out the Vivaldi size of the antenna can achieve a narrow beam. In determining unit day line, array of array antenna. The Vivaldi antenna as a point source, without considering the mutual coupling problem caused by the size of the antenna, for ring array on the simulation. And the actual Vivaldi antenna far field through the matrix into the array factor. Lobe pattern that Vivaldi ring array antenna. Then try to motivate the space array simulation. Comparing the two kinds of mode. By contrast, combined with the actual situation of the antenna selection, uniform linear array excitation. And feeder divider design of the antenna array design work. In the power divider on the choice of the ratio of Wei Seoul gold Sengong divider and T type device. Cm selected the T type power divider feeder of Vivaldi array antenna. In the way of sharpening the antenna beam, in addition to its element distribution arrangement, also can choose the other way, the introduction of reflector antenna and lens, try to use the angle of reflector antenna, by the simulation to observe the influence of beam width. We find that it has some restriction effect on lobe, but the cause of sidelobe is too large. The analysis found that the antenna phase after the radiation through the reflector after reflection and radiation prior to the superposition of two kinds of radiation similar to sidelobe increases. And then try to find Luneberg lens antenna to narrow the beam characteristics, the gain increases. According to the characteristics of electromagnetic wave propagating in different media, the establishment of hexahedral hole lens. Also can increase the gain, reduce the beam effect. This will be the most The combination of lens and Vivaldi array antenna shows that its limited beam steering ability is limited. Through analysis, it is obtained that when the beam width is about 3 degrees, because the ratio of gain to gain is smaller than its own gain, the narrow beam capability is relatively small.

【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN957.2

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