微小卫星全向天线设计

发布时间：2018-04-22 03:38

本文选题：微小卫星 + 四臂螺旋天线　；参考：《浙江大学》2014年硕士论文

【摘要】：微小卫星是当今航天领域的研究热点,其因具有体积小,研发周期短,研发成本低等优点而受到各航天强国的普遍重视,现已越来越广泛地应用于通信、对地遥感、行星际探测、科学研究和技术试验等。天线系统是卫星通信模块中不可或缺的一部分,对卫星系统性能的影响至关重要,而且往往占据着相当大的体积,随着微小卫星小型化、微型化的发展,也对应用于微小卫星的天线提出了小型化需求。四臂螺旋天线具有良好的半球心形方向图,其优良的宽波束和圆极化特性被广泛应用于卫星通讯。本文综述了微小卫星天线的一般要求,分析了四臂螺旋天线的结构和工作原理,并针对微小卫星的应用,解决了四臂螺旋天线小型化问题,为四臂螺旋天线在小卫星特别是皮卫星上得到应用打下基础。论文的主要工作与成果有： 1.详细分析了微小卫星的应用需求,基于此,提出了微小卫星天线的主要设计指标：具有上半空间的全向方向图,极化方式为右旋圆极化,工作频率为2.065GHz,轴向增益2dBi。针对传统四臂螺旋天线存在的不足,研究了其小型化和馈电的解决方案。 2.设计了一种圆柱体介质加载的四臂螺旋天线,工作频率为2.065GHz,其尺寸为高14mm,半径5mm,采用相对介电常数为36的微波陶瓷加载,利用同轴线通过天线轴心在顶部对天线馈电,天线底部集成套筒巴伦,实现平衡馈电,同时,利用激光刻蚀天线顶部螺旋臂实现四臂正交馈电。通过CST三维电磁仿真软件对天线设计进行仿真,结果表明,该天线具有宽波束的心形方向图,3dB波束宽度大于120度,在波束宽度范围内圆极化良好。最后利用仿真验证了激光刻蚀螺旋臂实现正交馈电的可行性。 3.针对介质天线的制作,本文提出了一种磁控溅射金属化加激光刻蚀的新工艺,利用计算机数控结合激光刻蚀的柔性加工技术完成陶瓷基体上螺旋臂的加工,简化了传统工艺,提高了加工精度,所制得的天线具备良好的机械性能,同时也为相关曲面共形天线的加工提供了参考。最后,对制作完成的天线进行了有关项目的实测,测试结果达到预期。
[Abstract]:Microsatellite is the research hotspot in the space field nowadays. Because of its advantages of small size, short research and development cycle and low R & D cost, it has been widely used in communication and remote sensing of the earth because of its advantages such as small size, short R & D cycle, low R & D cost and so on. Interplanetary exploration, scientific research and technical experiments. Antenna system is an indispensable part of satellite communication module. It is very important to the performance of satellite system, and often occupies a large volume. With the development of miniaturization and miniaturization of microsatellites, The miniaturization of the antenna used in microsatellites is also proposed. The four-arm helical antenna has good hemispheric heart-shape pattern and its excellent characteristics of wide beam and circular polarization are widely used in satellite communication. In this paper, the general requirements of microsatellite antenna are summarized, the structure and working principle of four-arm spiral antenna are analyzed, and the miniaturization problem of four-arm helical antenna is solved for the application of micro-satellite. It lays the foundation for the application of four-arm helical antenna on small satellites, especially on skin satellites. The main work and achievements of the thesis are as follows: 1. The application requirements of microsatellite are analyzed in detail. Based on this, the main design parameters of microsatellite antenna are proposed: the omnidirectional pattern with upper half space, the right-handed circular polarization, the working frequency of 2.065 GHz, and the axial gain of 2dBi. Aiming at the shortage of traditional four-arm spiral antenna, the miniaturization and feed solution are studied. 2. A cylindrical dielectric loaded four-arm spiral antenna is designed. The working frequency is 2.065 GHz, the size is 14mm, the radius is 5mm, the microwave ceramic is loaded with relative dielectric constant 36, and the coaxial line is fed to the antenna through the center of the antenna at the top. The bottom of the antenna is integrated with the sleeve Barron to realize the balanced feed. At the same time, the quadrature feed is realized by the laser etching of the top helical arm of the antenna. The antenna design is simulated by CST software. The results show that the beamwidth of 3dB beam with wide beam is larger than 120degrees, and the circular polarization is good in the range of beamwidth. Finally, the feasibility of realizing orthogonal feed by laser etching spiral arm is verified by simulation. 3. A new technology of magnetron sputtering metallization and laser etching is proposed for the fabrication of dielectric antenna. The machining of spiral arm on ceramic substrate is accomplished by computer numerical control combined with laser etching, which simplifies the traditional technology. The processing accuracy is improved and the antenna has good mechanical properties. It also provides a reference for the machining of the conformal antenna with curved surface. Finally, the antenna is measured and the test results are up to expectations.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN828.5

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