【作者】 郭敏；

【导师】 钟顺时；

【作者基本信息】 上海大学 ， 电磁场与微波技术， 2016， 博士

【摘要】 随着频谱资源的不断开发和使用,宽带、小型化与双极化等技术在未来无线通信系统中变得越来越重要,尤其在卫星通信、电子对抗等国民经济和军事应用领域。为此本论文主要对应用于双波段双极化天线阵的介质谐振器天线(Dielectric resonator antenna简称DRA)、圆极化介质谐振器天线阵作了一些较为深入的研究工作,同时,本文还对共口径双波段双极化阵列天线作了一些研究。本文主要包括以下几方面内容:第一,研制了高隔离度双极化介质谐振器天线。文章详细介绍了双极化DRA的设计,探讨了DRA形状、大小等参数对天线性能的影响,考察了平衡馈电激励方式在改善天线交叉极化指标方面的作用,并对平衡缝隙馈电进行了参数研究。加工了实验天线,其实测的水平和垂直极化阻抗带宽(S11≤-10dB)分别达30.43%和28.07%,而实测隔离度在5.8~8.0GHz带宽上大于39.93dB,居当前国际先进水平。第二,本章介绍了一种新型圆极化低副瓣介质谐振器天线阵,采用不等幅馈电网络实现了天线方向图的低副瓣,该馈电网络在很宽的频带上具有良好的阻抗匹配、功率分配和90°移相性能。对天线的性能进行了仿真研究,给出了驻波曲线、轴比曲线和辐射方向图,结果表明该天线阻抗带宽达到6.03%(VSWR≤2),覆盖了6.66-7.07GHz的频率范围,天线的轴比带宽为6.91%(AR≤3),天线增益在较宽的工作频带上大于11.7dB,天线副瓣电平达-20dB,基于上述优点,该天线在卫星通信系统中具有很好的应用前景。第三,介绍了一种新型的Ku波段双频双极化微带天线单元及其阵列设计。该阵列为多层结构,单元形式采用叠层的方形贴片形式,实现宽带双频的性能。不同极化的馈电网络设置在不同的介质层,实现高极化隔离和低交叉极化特性。16×16元子阵仿真与测试结果表明;水平极化和垂直极化端口相对阻抗带宽(VSWR≤2)分别达14.28%和16.6%,双极化端口隔离度优于33.3dB。该子阵在工作频段内增益大于27.67dB。更多还原

【Abstract】 With the spectrum resources being developed and applied, the techniques of wideband, miniaturization and dual-polarization are increasingly important in the wireless communication system in the future, especially for national economy and military applications, such as the satellite communications, electronic warfare systems, etc. Thus this dissertation proposes the novel designs of wideband and dual-polarization dielectric resonator antenna with high isolation and a wideband circularly polarized rod antenna, finally, a new type of dual-polarization and dual-frequency multilayer-stacked microstrip array antenna is introduced with experimental verification. Three main subjects are included:Firstly,A new design of dual-polarized dielectric resonator antenna with high isolation over a wide bandwidth is introduced, which isfed by utilizing the bowtie-shaped slot coupling. Four identical bowtie slotsare arranged symmetrically in an unconnectedcross configuration in the center. The isolation between two orthogonalpolarizations of the proposed antennais greatly improved over theconventional cross slot.The proposed antenna prototype has been fabricated and measured. Both simulated andmeasuredresults show that the proposed antenna has a port isolation of about40 dB over the impendence bandwidth(|S11|≤10d B)of 28-30%.Moreover, stableradiation patterns anda peak gain of 5.0–6.4dBi areachieved within the operating band. Its good polarizationpurity and broadside radiation patterns are confirmed also.Secondly,The design of a low-sidelobe circularly-polarized rectangular dielectric resonator antenna array is presented. In addition, a novel, simple and generic transmission line circuit model is developed. The proposed antenna prototype has been simulated. The results verify that it exhibits advanced characteristics with an impedance bandwidth(VSWR ≤ 2) of 6.03%, an axial ratio bandwidth(AR ≤ 3 dB) of 6.91%. Its simulated maximum gain is 11.7dB with a gain variation of 2.2dB over the bandwidth.Thirdly,A new type of dual-polarization and dual-frequency multilayer-stacked microstrip array antenna is introduced. The feeding mechanism of the element is the aperture coupling for one polarization and the direct feeding for the orthogonal polarization. The microstrip element exhibits a wideband of operation. A slot etched on driven patch is used to improve isolation performance of the proposed antenna element, and the better impedance characteristic is obtained as well. Measured results agree well with the simulation, exhibiting a |S11|≤10dB bandwidth of 16.6% in V-port and 14.28% in H-port. The measured isolation is better than 33.3dB. Good radiation patterns and low cross-polarization level are also confirme更多还原