导航终端天线的关键技术研究

发布时间：2018-05-28 22:24

本文选题：圆极化 + 多频　；参考：《电子科技大学》2014年硕士论文

【摘要】：使用GPS或者我国的北斗导航终端设备都有可能因为意外而无法使用导航定位系统。如果终端设备能同时兼容这两套导航定位系统,那么就会大大降低这种风险。而导航终端天线是其不可或缺的一部分,目前市场上面能同时兼容这两套导航定位系统的终端天线很少。本文在此基础之上,结合科研项目实际需要,研制了两款导航终端天线。另外基于项目需要,研制了一款用于单层双极化平面微带反射阵的双极化馈源。首先,在相关理论基础之上,研究设计了一款是用于车载的四频导航终端天线,采用多层结构,加载空气腔,以威尔金森和分支线耦合器为馈电网络,走立体结构,采用末端焊接有电容片的探针对辐射结构耦合馈电,实现宽频、多频(四频)、高增益的一款车载导航终端天线。使用电磁仿真软件进行仿真设计并送出去加工,对加工回来的天线进行测试,在BD2-B1与GPS-L1、BD1(Tx)、BD1(Rx)四个工作频点上,测试增益高于6.2 dB,前后比优于18.2 dB,20o仰角增益高于-6.3dB,轴比小于1.7dB,端口回波损耗高于17 dB,端口之间隔离度优于11.5dB。测试结果与仿真结果比较吻合,满足工程需要。其次,在上一款天线基础上,结合工程要求,设计了一款是用于手持终端的四频导航终端天线。采用双层结构,加载感性销钉,外方环内套有方形贴片的辐射结构,以耦合器芯片与威尔金森功分器连接末端焊接有电容片的探针作为馈电网络,以此实现多频、小型化,低仰角增益。经过理论分析,使用电磁软件仿真计算,加工制作了此款天线,并对其测试。在BD2-B1与GPS-L1、BD1(Tx)、BD1(Rx)四个工作频点上,测试增益高于3.4 dB,前后比优于13.5 dB,20o仰角增益高于-5dB,轴比小于2.8dB,三个端口各自回波损耗优于14dB,端口之间的隔离度高于11.5dB,测试与仿真比较吻合,基本满足工程设计要求。最后,基于项目需要,设计了一款双极化馈源,采用双耦合接入的正交膜耦合器进行双极化信号的隔离与混合,端接正交膜耦合器的多模喇叭用作偏馈馈源,对单层双极化平面微带反射阵进行馈电。结合理论与仿真计算,制作了馈源实物,并对其测试,测试结果表明,在工作频段(31-33GHz)内,馈入的耦合端口的反射系数均小于-10dB,两馈电端口之间的隔离度大于40dB,插损小于1dB,增益高于13.5 dB,10 dB波束宽度大于72o,测试与仿真结果吻合,且很好的满足了工程要求。
[Abstract]:The use of GPS or our country's Beidou navigation terminal equipment may be accidental and unable to use the navigation and positioning system. If the terminal equipment is compatible with both sets of navigation and positioning systems, the risk will be greatly reduced. The navigation terminal antenna is an indispensable part of the system. At present, few terminal antennas are compatible with these two navigation and positioning systems on the market. Based on this, two navigation terminal antennas are developed according to the actual needs of scientific research projects. In addition, a double polarization feed is developed for single layer dual polarized planar microstrip reflectors. First of all, on the basis of related theory, a four-frequency navigation terminal antenna used in vehicle is designed. It adopts multi-layer structure, loads air cavity, takes Wilkinson and branch coupler as feed network, and walks stereoscopic structure. A wideband, multi-frequency (four-frequency), high-gain antenna for vehicle navigation terminal is realized by coupling the radiation structure with a probe with a capacitor chip welded at the end of the paper. The electromagnetic simulation software is used to simulate the design and to be sent out for processing. The processed antennas are tested at the four working frequency points of BD2-B1 and GPS-L1N BD1TxTX / BD1 / Rx, and the results are as follows: (1) the electromagnetic simulation software is used to carry out the simulation design, and the processed antenna is tested. The measured gain is higher than 6.2 dB, the forward / backward ratio is better than -6.3dB, the axial ratio is less than 1.7dB, the return loss is more than 17 dB, and the isolation between ports is better than 11.5dB. The test results are in good agreement with the simulation results and meet the engineering needs. Secondly, based on the above antenna and the engineering requirements, a four-frequency navigation terminal antenna for handheld terminal is designed. Using double layer structure, loaded inductive pin, square patch inside the outer ring, using coupler chip and Wilkinson splitter to connect the end of the probe with capacitor as feed network, so as to realize multi-frequency and miniaturization. Low elevation gain. After theoretical analysis, the antenna is fabricated and tested by electromagnetic software simulation. At the four operating frequency points of BD2-B1 and GPS-L1TX TX, the test gain is higher than 3.4 dB, the back to back ratio is better than 13.5 dB, the axial ratio is less than 2.8 dB, the return loss of the three ports is better than 14 dB, and the isolation between ports is higher than 11.5 dB. The test results are in good agreement with the simulation results. Basically meet the requirements of engineering design. Finally, based on the project requirements, a dual-polarization feed is designed. The dual-polarization signal is isolated and mixed by a dual-coupled quadrature film coupler, and the multi-mode horn connected with the orthogonal membrane coupler is used as the feed. A single layer double polarized planar microstrip reflection array is fed. Combined with the theory and simulation calculation, the feed material is made and tested. The test results show that, in the working frequency band of 31-33 GHz, The reflection coefficient of the fed coupling port is less than -10 dB, the isolation between the two feed ports is more than 40 dB, the insertion loss is less than 1 dB, the gain is higher than 13.5 dB and 10 dB beam width is larger than 72 o. the test results are in good agreement with the simulation results and well meet the engineering requirements.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN965.2

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