带寄生单元宽带单极子天线研究

提出并设计了一种带寄生单元宽带单极子天线,该天线由一个单极子天线附加两个寄生振子组成.仿真及实验结果证明:天线在保持单极子天线特性的同时,实现了其宽带特性.该天线在750～2240 MHz的频带内反射损耗小于-10 dB,具有水平全向的方向图、稳定的增益.天线的结构和电特性决定了天线有广阔的应用前景,非常适用于移动通信终端设备,作为手持终端天线和车载天线将大有可为.     

一种宽带水平全向平面天线设计

为提高水平全向天线的带宽,设计了一种宽带水平全向平面天线。该天线由4只弧形偶极子天线组阵构成一个圆环,每只偶极子天线振子交错印刷在印制板的上下表面。将4只弧形偶极子远场方向图叠加组合为水平全向辐射方向图;在每只偶极子振子上开缝并在印制板边缘加载寄生贴片,增加天线的带宽。设计和加工制作一只天线样品,测试结果表明,该天线能够在2~3.71 GHz实现|S11|<10 dB,相对带宽达到60%,水平全向平均增益约为1.36 dBi,不圆度小于±1.5 dB,测试与仿真结果吻合良好。     

卫星导航复合多功能桅杆天线的研究

本文利用双寄生套筒的结构,采用双锥和粗振子结合的辐射体形式设计了一款可与卫导天线级联的全向宽带穿杆天线。采用这种特殊结构该天线解决了常规天线内部穿金属接地杆后驻波恶化的问题。仿真和实测结果表明天线在120-550MHz频带内电压驻波比小于2.5,且高低频端的方向图全向性良好。     

复杂涌流下水下自主航行器横滚抑制控制仿真

在复杂的海洋涌流背景下,水下自主推进航行器受到扰动较大,出现横滚导致控制稳定性下降,提出一种基于模糊PID扰动抑制的复杂涌流下水下自主航行器横滚抑制算法.构建在复杂涌流下的水下自主航行器运动状态模型,在航行器的纵向运动全包线内对横舵角、横滚角、回旋角等运动约束参量进行定常运动分析,采用模糊PID神经网络控制模型进行控制律的改进设计,结合Lyapunov稳定性原理进行横滚抑制和误差修正,实现控制算法改进.仿真结果表明,采用该控制算法进行复杂涌流下水下自主航行器横滚抑制控制,具有较好的输出响应跟踪性能,有效抑制横滚,提高了水下自主航行器的稳定控制能力,鲁棒性较好.     

230MHz无线专网小型化平板天线设计

提出了一种用于电力230 MHz无线专网的平板天线,天线工作频率228～237 MHz,相对带宽3.9％.该天线由单层1 mm厚度FR4印制板的倒F结构辐射体组成,天线整体尺寸300 mm×260 mm×1 mm.天线通过匹配传输结构将馈电点放置于辐射体背部,便于安装.经过仿真天线增益性能良好,水平全向增益1.5 dB...     

一种宽频带高增益高极化隔离度的微带天线

设计了一种具有高增益、高极化隔离特性的宽频带层叠型E形天线。通过激励E形辐射体,获得双峰谐振回路,并在E形天线上方附加寄生元,构成了三峰谐振特性,从而取得较传统E形天线更宽的频带;通过E形天线在低端激励的双电流路径保证了天线在频率低端的高增益特性,而天线本身的辐射体尺寸保证了频率高端的高增益特性。采用Ansoft HFSS电磁仿真软件对提出的天线模型仿进行优化,依次在1.75 GHz,2.1 GHz,2.475 GHz形成了三个谐振峰值;在1.7~2.54 GHz内驻波比≤1.5,其相对带宽达40％,在1.7~2.5 GHz频带内增益＞8 dBi,且具有低达-55 dB的优异交叉极化特性。     

一种圆形智能天线阵列与校正网络的设计

论述了一种用于智能天线系统的新型圆形天线阵列与校正网络的设计方法.设计了一种具有良好一致性和高增益全向特性的新型直排印刷振子天线结构,并采用奇偶模分析方法,实现了一种1:8威尔金森功分器/合路器与平行耦合线定向耦合器相结合的校正网络.实验结果证明,研究结果对于3G通信具有很高的实用价值.     

蝶形双偶极子宽带印刷端射天线设计

文中提出了一款新的蝶形双偶极子宽带印刷端射天线.在该天线设计中,引入阶梯槽线结构来改善天线带宽上的阻抗匹配,拓宽天线的带宽;在地板反射器和双偶极子驱动器上加载蝶形枝节来加长天线的电流流径,实现天线尺寸减小和带宽提高;在不改变天线尺寸的前提下,在引向器上下两边加载寄生贴片,扩大天线辐射口径,进一步提高天线的带宽和增益.所...     

微带磁流振子天线综述

文章综述了微带磁流振子天线的最新发展情况,从理论上对比了微带磁流振子天线和电流振子天线的辐射机理,阐述了微带磁流振子具有水平极化和高增益的新颖性,最后介绍了微带磁流振子在新型天线阵列、圆极化天线、高增益天线的应用。     

一种新型全向高增益印刷天线的设计

设计了一种新型全向高增益印刷天线。该天线采用平衡微带线作馈线．以印刷振子作为辐射单元，末端采用匹配电路对其输入阻抗进行匹配。用商用软件AnsoftHFSS对天线的特性进行了仿真计算。比较表明，测试结果优于仿真结果。该天线工作在SCDMA频段（1785～1805MHz），其H面不圆度小于1dB，中心频率下增益大于12dB，满足了设计要求。     

Small Printed Ultrawideband Antenna With Reduced Ground Plane Effect

A small printed antenna is described with a reduced ground-plane effect for ultrawideband (UWB) applications. The radiator and ground plane of the antenna are etched onto a piece of printed circuit board (PCB) with an overall size of 25mmtimes25 mmtimes1.5 mm. A notch is cut from the radiator while a strip is asymmetrically attached to the radiator. The simulation and measurement show that the miniaturized antenna achieves a broad operating bandwidth of 2.9-11.6 GHz for a 10-dB return loss. In particular, the ground-plane effect on impedance performance is greatly reduced by cutting the notch from the radiator because the electric currents on the ground plane are significantly suppressed at the lower edge operating frequencies. The antenna features three-dimensional omni-directional radiation with high radiation efficiency of 79%-95% across the UWB bandwidth. In addition, a parametric study of the geometric and electric parameters of the proposed antenna will be able to provide antenna engineers with more design information     

A High Gain and Broadband C-Band Aperture-Coupled Patch Antenna

A aperture-coupled patch antenna is designed with parasitic elements connecting to the rectangle ring on the bottom of antenna substrate through metal vias, which lead the current induced by patch radiator to the top surface of antenna substrate. Therefore, the effective radiation is enhanced and higher gain is achieved. The bandwidth is broadened simultaneously due to the structure of aperture-coupled patch antenna with parasitic elements. Compared to the conventional aperture-coupled patch antenna, the antenna gain increases averagely 2 dB due to the novel structure. Compared to patch antenna of electromagnetic band-gap, the dimensions of novel patch antenna greatly decreases, which can be used as element in the array antenna. Two kinds manufactured antenna are both measured in an anechoic chamber. The good agreements between numerical simulation and experimental prototype have been obtained.     

一种套筒单极天线组成的宽带测向阵列

介绍了一种加粗的套筒单极天线,并作为测向单元使用。运用HFSS电磁仿真软件进行参数优化,在单元驻波与水平面增益满足工程情况下有效降低了天线高度。将这种套筒单极天线组成圆阵,在得出阵列电磁特性的基础上再运用最小二乘法分析了圆阵测向性能。结果表明,该测向天线阵在灵敏度、测向精度及阵列高度上都有一定的优势,特别适合于一些运动平台安装使用。     

解耦合的紧凑微带天线阵设计

设计出一种新型结构的解耦合微带天线阵,用折叠型微带电路替代集总元件电路,简化了电路结构,便于加工制作;天线采用倒L结构作为辐射单元以减小天线的尺寸;端口的匹配采用阶梯形阻抗匹配器来提高匹配程度。仿真和实测结果显示,该天线阵工作在2.45 GHz,天线单元反射系数和天线单元间的隔离度在工作频段（2.4 GHz-2.48 GHz）内均小于-20 dB,天线远场保持了较好的全向性。     

On the design of a dual-band base station wire antenna

A dual-band base station wire-antenna design is presented. The MoM and the simulated-annealing technique, for optimizing the antenna geometry, are used. The procedure starts from the design of a primary radiator, consisting of a dielectric covered driven dipole and a parasitic element. A Chebyshev antenna array is checked in both the 900 and 1800 MHz frequency bands, with and without the appropriate feed network. All the electrical characteristics, as well as the patterns of the antenna, are presented     

Ku band pattern reconfigurable substrate integrated waveguide leaky wave horn antenna

A dual band substrate integrated waveguide H plane sectoral horn antenna with reconfigurable radiation characteristics has been proposed in this paper. Designed antenna acts as a perfect broadside radiator at 16.1 GHz and perfect endfire radiator at 14.4 GHz frequency. Broadside radiation has been achieved by etching rectangular slots in the flared section of horn exhibiting a gain of 8.87 dBi. To achieve perfect endfire radiation, dielectric loading is done at the edge of horn and at this frequency antenna shows a gain of 11.3 dBi. The horn and the loaded dielectric are integrated by using the same single substrate resulting in easy fabrication and low cost. The proposed design has been fabricated and measured results are in good agreement with the simulated results.     

天线相位中心暗室标定法远场条件研究

将有限测试距离引入的测相误差公式由一维辐射源拓展到二维口径辐射源.与传统相位方向图误差分析中只考虑单一方向上测相绝对误差的方法不同,提出全新的基于保证有限测试距离处不同方向相位差与远场相位差一致的有限测试距离相位中心测量误差分析方法.利用文献[6]的天线相位中心暗室测量方法,对有限距离引入的误差进行了数值分析,从而得到满足一定精度要求的远场测量条件.以实际天线相位中心标定例子说明了分析方法的正确性.     

一种改进的小型超宽带天线

为了有效地对超宽带天线进行小型化,通过对平面椭圆单极子超宽带天线进行切半和切边处理,设计了尺寸为10mm×17mm的小型超宽带天线。为了改善因对天线进行切半而恶化的全向辐射特性,在小型超宽带天线的辐射体中引入了缝隙结构。仿真结果表明:改进的小型超宽带天线在整个超宽带频带内具有良好的阻抗匹配和全向辐射特性。该天线的测量结果与仿真结果基本吻合。     

Radio Propagation Model Considering Antenna Beam Tilt with Application to Small Cells

Antenna beam tilting techniques are commonly used to deploy small cells with reduced coverage compared than macrocells. This paper proposes a new statistical propagation model for small cells with electrical and mechanical antenna tilt. The proposed model combines the dual slope path loss model with the departure angle spread model for considering antenna beam tilt. The proposed departure angle spread model introduces a new parameter reflecting the azimuth spread of departure (ASD) angles in order to account for the change of transmit antenna gain by electrical and mechanical tilt. Through this approach, the antenna gain for each ray is separately computed by considering the transmit antenna beam pattern as well as the antenna beam tilt. We perform field tests to measure the receive signal power in the downlink of commercial Long-Term Evolution small cells with antenna tilt. Based on the measurement data, we find the statistically optimal ASD parameter using a grid search and calculate the antenna gain for each ray. Also, the overall transmit antenna gain is obtained by averaging antenna gains for multiple rays. To assess the accuracy of the proposed model, the estimation error is evaluated by comparing the measured receive signal power with the estimated value using a propagation model, and the performance of the proposed propagation model is compared with those of existing path loss models in terms of root mean square error deviation. Then, it is shown that the proposed model provides more accurate propagation estimation for small cells than existing models.