郝汉 9:50:25
随着人类社会日益增长的通信需求，研究人员将天线应用在各种各样的场景中，包括室外环境，城市地区和室内系统。因此，要满足复杂多变通信需求，需要使用不同功能的天线，特别是室内环境存在空间限制、多径效应和遮挡等问题。圆极化微带天线具有轻质量、低剖面、设计加工方便、抵抗多径效应等优点。因此，被研究人员广泛应用在卫星、射频、车载天线和移动通信等方面。它对多径效应造成的衰落损耗有很显著的效果。此外，圆极化天线不考虑接收天线相对于发射天线的方向，因此它适用于空间受限的室内无线应用方面。
针对单个天线增益过低的问题，设计工作在5G毫米波频段的微带阵列天线，并采用并联馈电网络的设计，阵元间的电流等幅同相。该阵列天线的阻抗带宽为24.9-25.6 GHz，在26 GHz处的最大增益为17 dBi，E面和H面的副瓣电平分别为-6.57 dB和-6.47 dB，半功率波瓣宽度分别16°和18°。该阵列天线具有较高的增益并且有满足工作需求的带宽，可应用于5G毫米波频段，但同时存在轴比带宽较窄的问题。
针对轴比带宽不足的问题，设计了超表面的紧凑型宽带CP天线阵列。该天线阵列是一组2×2的CP缝隙天线，通过在环形缝隙天线加入十字缝隙和采用SP馈电网络，极大地提升了阻抗带宽，通过加入超表面结构来实现电磁波的线圆转化。天线的尺寸为78×78×10.1mm3。天线的-10 dB带宽为3.18-6.2 GHz (64%)，3dB AR带宽为3.94-5.24 GHz(28.32%)。同时，本文天线的波束宽度为60°，具有良好的辐射性能。该天线的工作带宽覆盖5G频段，可用于复杂场景下的5G频段通信。
针对天线辐射前后比和带宽的问题，设计了采用人工磁导体结构的顺序相位馈电宽缝阵列天线。介绍了天线的设计方法和作用原理，并在微波暗室中对天线实物进行了测试。首先，天线辐射单元的设计增加了轴比带宽，采用SP馈电网络来连接形成阵列，在天线下方放置人工磁导体结构，增加了天线正向的辐射，并且减小了天线空气层高度。实验结果表明，设计的天线达到了77.67% (2.74-6.22 GHz)的阻抗带宽，并且拥有65.16% 轴比宽带(3.00-5.90 GHz)，天线的剖面高度为0.11 λ0。本章节设计了加载人工磁导体结

郝汉 9:50:39
构的顺序相位馈电宽带圆极化宽缝阵列天线，具有高增益，宽频带、低成本的优点，可用于空间受限的环境，如室内和密集建筑区域。
本文中所介绍的三种阵列天线主要应用在室内场景下，同时通过优化天线的辐射阵元、馈电网络、加载超表面的方式来提升天线性能。在设计天线方面也充分考虑到天线的实际应用价值，采用更低成本的加工方式的基板材料，最大化的提升天线性能。使天线在室内5G基站天线方面有更好的应用价值，实现信号覆盖的盲点补充。

With the growing communication needs of human society, researchers have applied antennas in a variety of scenarios, including outdoor environments, urban areas, and indoor systems. In fact, in the case of the indoor environment, the electromagnetic signal propagation faces a great challenge, due to the external interference in the environment also has a requirement on the stability of wireless communication system, for the line polarization antenna is not able to meet the needs of the application. Circular polarized microstrip antenna have the advantages of light mass, low profile, easy design and processing, and resistance to the multipath effect. Therefore, it is widely used by researchers in satellite, RF, vehicle antenna, and mobile communication. It has a remarkable effect on the fading loss caused by the multipath effect. In addition, the circularly polarized antenna does not consider the direction of the receiving antenna relative to the transmitting antenna, so it is suitable for space-constrained indoor wireless applications.
A microstrip array antenna operating in the 5G millimeter band was designed to solve the low gain problem of a single antenna. The array antenna has an impedance bandwidth of 24.9-25.6 GHz, a maximum gain of 17 dBi at 26 GHz, SLL of -6.57 dB, and -6.47 dB in the E-plane and H-plane, respectively, and half-power flap widths of 16°and 18°, respectively. The array antenna has a high gain and a bandwidth to meet the working demand, which can be applied to a 5G millimeter-wave band, but there is also a problem of narrow axial ratio bandwidth.
The compact broadband circularly polarized (CP) antenna array with super surface is designed for the problem of insufficient axial ratio bandwidth. The antenna array is a set of 2×2 CP slot antennas, which greatly enhances the impedance bandwidth by adding cross slits to the ring slit antenna and employing an sequential phase (SP) feed network, and the line-circle conversion of electromagnetic waves by adding a metasurface structure. The dimension of the antenna is 78×78×10.1 mm3. The -10 dB bandwidth of the antenna is 3.18-6.2 GHz with the relative bandwidth of 64%, and the 3 dB axial ratio (AR) bandwidth is 3.94-5.24 GHz with the relative bandwidth of 28.32%. Meanwhile, the antenna in this paper has a beamwidth of 60° with good radiation performance (peak gain is 6.2 dBi). The operating bandwidth of the antenna covers the 5G band, which can be used for 5G communication in complex scenarios.
The SP-fed wide slot array antenna with artificial magnetic conductor (AMC) structure is designed for the problems of antenna radiation front-to-back ratio and bandwidth. The design method and the principle of the antenna are introduced, and the antenna is simulated and tested in a microwave anechoic chamber. Firstly, the antenna radiation unit is designed to increase the axial ratio bandwidth, and the SP-fed network is used to connect to form the array. Secondly, the AMC structure enhances the radiation performance of the antenna in the +z direction and reduces the antenna profile at the same time. The experimental results show that the designed antenna achieves 77.67% (2.74-6.22 GHz) impedance bandwidth and has 65.16% axial ratio bandwidth (3.00-5.90 GHz) with a profile height of 0.11 λ0. Our designed SP-fed broadband circularly polarized wide-slot array antenna loading with AMC structure has the advantages of high gain, wide bandwidth, low cost, and can be used for space-constrained applications. It has the advantages in space-constrained environments, such as indoor and dense building areas.
The three array antennas introduced are mainly used in indoor scenarios, while continuously optimizing the antenna's radiation array elements, feed network, and loading super surface to improve the antenna performance so that the designed antenna impedance and axial ratio bandwidth and gain have been significantly improved. The design of the antenna also fully considers the practical application value of the antenna, adopt a lower cost processing method of substrate material, and maximizes the performance of the antenna. So that the antenna has better application value in indoor 5G base station antenna and realizes the blind spot supplement of signal coverage.

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