Aperture-Miniaturized Antenna Loaded with Split Ring Resonator Array

In this letter, a novel antenna with a miniaturized aperture is proposed. The substrate including a split-ring resonator array is inserted into a size-reduced open-ended waveguide. For a low return loss and high radiation efficiency, the ring arrangement is optimized, and a stepped transition using H-plane discontinuity is proposed. The proposed antenna achieves a 70% aperture reduction compared to a conventional standard waveguide antenna of WR-187 (47.6 mm×22.2 mm). The return loss drops significantly at three frequencies, and a reasonable gain is achieved. The aperture-miniaturized antenna can be used in many antenna applications such as near-field measurement.     

Design of an Ultra‐Wideband Antenna Using a Ring Resonator with a Notch Function

This paper describes an ultra‐wideband (UWB) antenna that uses a ring resonator concept. The proposed antenna can operate in the entire UWB, and the IEEE 802.11a frequency band can be rejected by inserting a notch stub into the ring resonator. The experiment results indicate that the measured impedance bandwidth of the proposed antenna is 17.5 GHz (2.5 GHz to at least 20 GHz). The proposed UWB antenna has omnidirectional radiation patterns with a gain variation of 3 dBi (1 dBi to 4 dBi).     

二氧化硅光波导环形谐振腔

利用宽角光束传输法(WA-BPM)对二氧化硅平面波导环形谐振腔进行了优化设计,详细分析了不同环形腔长度下,谐振腔清晰度与环形腔耦合器耦合系数的关系,并进一步分析了由光探测器散弹噪声所限制的谐振型光学陀螺极限灵敏度和环形腔光路参量之间的关系。在此基础上,在硅衬底上利用火焰水解化学掺GeO2的二氧化硅波导上制作成带输入/输出耦合器的环形谐振腔芯片。并通过实验测试了所研制的光波导环形谐振腔,其清晰度高达60,理论分析表明采用上述环形谐振腔研制的陀螺,其极限灵敏度可达1°/h。     

有源波导环形谐振腔滤波特性分析

将掺铒有源波导材料引入环形谐振腔结构，从理论上分析了有源波导环形谐振腔的滤波特性。结果表明由于抽运光提供的增益补偿了腔内损耗，使得环形谐振腔满足临界耦合条件，实现对信号光的最佳陷波，同时发现通过改变抽运光功率，可以对精细度和带宽进行动态调谐。分析了铒离子掺杂浓度、信号光功率以及抽运光耦合系数对最佳陷波抽运功率的影响，为有源波导器件设计制作提供了理论依据。     

Open‐Ended Two‐Strip Meander‐Line Antenna for RFID Tags

A new meander‐line antenna consisting of two open‐ended strips is proposed for a compact and broadband UHF radio frequency identification tag. An equivalent circuit model for the proposed antenna is derived and used to perform a simple and wideband impedance match to an arbitrary complex impedance of a tag chip without any additional matching network. The performance of the proposed antenna is validated by comparing calculated and measured results, which show good agreement.     

利用有机-无机溶胶-凝胶方法制备平面波导环形谐振腔

采用简单的有机-无机混合的溶胶-凝胶方法制备了折射率在一定范围内可调的波导材料,并利用其制备了平面波导环形谐振腔器件。波导结构呈现倒脊形,其制备工艺首先是利用感应耦合等离子体刻蚀技术(ICP)在二氧化硅衬底上刻蚀波导结构的凹槽,然后再沉积波导薄膜。利用光谱仪对器件的传输特性进行了测量,观测到具有10 dB对比度,自由光谱范围0.182 nm周期性谐振现象,结合环形谐振腔的传输特性,得到环形腔具有较低的传输损耗1.7 dB/cm。同时对环形谐振腔的温度特性进行了测量,得出波导材料的热光系数为-1.54×10-4/℃。     

波导中开口谐振环的实验研究

金属开口谐振环(split ring resonators,SRRs)是组成负磁导率结构材料的基本结构单元.本文利用波导法系统地研究了六边形SRRs的微波透射、吸收以及传输相位随频率的变化特性.实验结果表明:单个SRRs的谐振频率随内外环间距的增加而减小,且传输相位在谐振频率处发生跃变;两个SRRs间的相互作用随其间距的变化而变化,即谐振频率随间距的增加而增加,且在谐振频率处吸收出现最大值;多个以一定间距排列的SRRs列的电磁谐振行为可由环的开口大小调控,且谐振频率随开口间距的增加而增加.SRRs电磁谐振行为的研究对于左手材料的制备具有一定的指导意义.     

Efficient Method to Extract Coupling Ratio and Round-trip Loss Parameters of Optical Waveguide Ring Resonator

Based on the measurement of the contrast ratios of the transmission spectra from the throughput and drop ports of ring resonator, an efficient method is proposed to extract the coupling ratio and round-trip loss of the integrated optical waveguide ring resonator. The parameters of a racetrack resonator prepared by ion-exchange technique in K9 optical glass substrate are examined, which demonstrates the validity of this method. The accuracy and applicable range of this method are also discussed.     

一种新型波导口单脉冲天线设计

提出了一种新型波导口单脉冲天线阵设计,分别给出了驻波曲线和辐射方向图的测试结果。该天线辐射单元采用呈90°结构的小型化波导口形式,通过底部的馈电倾斜缝馈电实现阵面的锥削分布要求,克服了传统波导缝隙天线设计复杂及对加工精度要求高的缺点,实现较为简单。采用理论与实验相结合的方法分析了测试结果与仿真结果差距较大的问题,去除了较为敏感的短路块结构,综合考虑工程可实现性及电性能两个方面,对辐射单元进行了二次优化设计并完成了天线实物加工。实验结果表明,该天线具有2.7% 的带宽(驻波不大于2),-20 dB 副瓣性能和45%的辐射效率,实现了与传统波导天线相当的单脉冲性能,为波导天线设计提供了一种新的方法,在弹载星载领域具有较广泛的工程应用前景。     

小型化窄边单脊波导滤波器设计

通过仿真分析了窄边单脊波导的基本特性,采用所加脊不贯穿整个波导纵向的形式作为单脊波导谐振器,组成直接耦合的切比雪夫带通滤波器,同时输入、输出采用了同轴馈电的方式,与标准波导滤波器相比,可大幅度减小滤波器的体积。最后得到的测试结果表明,该结构能很好地实现波导滤波器的小型化设计。     

Enhanced‐Gain Planar Substrate‐Integrated Waveguide Cavity‐Backed Slot Antenna with Rectangular Slot Window on Superstrate

A novel substrate‐integrated waveguide (SIW) cavity‐backed slot antenna is proposed in this study to achieve enhanced‐gain performance. The peak gain is remarkably improved with the use of an SIW cavity and metallic superstrate. The superstrate comprises a single rectangular slot window and two half‐wavelength patches. The gain can be enhanced by combining the in‐phase radiating fields. Further, the 10 dB bandwidth of the proposed antenna ranges from 2.32 GHz to 2.49 GHz, which covers the wireless local area network band. The measured peak gain is 9.44 dBi at 2.42 GHz.     

一种基于开口谐振环的高增益宽带双极化天线设计

该文设计并制作了一种基于超材料的高增益宽带双极化天线,该天线由两个正交放置的印刷振子单元、馈电巴伦及金属接地板构成。为了进一步展宽带宽、提高增益,在天线上了加载开口谐振环、互补开口谐振环等超材料结构。测试结果表明,该天线回波损耗小于-10 dB的带宽约为69%(0.98~2.01 GHz),在相同的频带内隔离度大于20 dB。由于开口谐振环的引向作用,天线的辐射特性得到改善,增益最大提高了4.1 dB左右。和已有设计相比,该天线的总体高度减小了约12%。其可以当作独立天线使用,也可用作反射面天线的双极化馈源。     

Circular Polarization Dielectric Resonator Antenna Excited by Single Loop Feed

A new feeding method for the circular polarization (CP) dielectric resonator antenna (DRA) is proposed in this letter. Two orthogonal modes (TE^x_δ11, TE^y_1δ1,) of the rectangular DRA are excited by a 90° phase difference of the differential and common modes currents of the proposed feeding structure. To demonstrate the good CP performance of the proposed method, a right‐hand CP DRA for a global positioning system was designed. The impedance bandwidth of the proposed antenna for S₁₁相似文献   

一种利用环形双模谐振器实现的带阻滤波器

提出了一种利用双模环形谐振器实现的带阻滤波器。该滤波器由一个对称的双模环形谐振器以及一段四分之一波长的平行耦合线组成。借助于在普通环形谐振器的两个相对边上添加一对小贴片,环形谐振器的两个简并谐振模式可以被可控的分离,从而可以构成带阻滤波器的工作频带。平行耦合线的作用是为了对双模谐振器进行馈电,同时也被用做两端口间的阻抗变换器。在理论分析之后,利用平面PCB工艺设计制作了滤波器样品,并对其进行了测量,进一步证明这种设计的有效性。     

CPW馈电的超宽带天线设计

设计了一种基于共面波导(CPW)馈电的超宽带(UWB)天线。该天线由以低成本的FR4为介质基板,以馈线为中心的两个不对称的接地板和一个开口谐振环组成。天线结构简单紧凑,尺寸仅为31.6 mm×48 mm×1.6 mm。通过在其中一侧地板上方增加一个开口谐振环,不仅使天线的工作频带变宽,且也减小了天线的尺寸。最终天线的回波损耗为-10 dB,带宽为2.33～11.75 GHz。结果表明,该文设计的天线适用于无线通信系统。     

共面波导馈电的小型化双通带滤波器

提出了一种采用共面波导馈电的小型多模双通带平面滤波器,该滤波器采用内部嵌套的多模谐振器缩小了电路尺寸,利用奇偶模分析方法和弱耦合激励的方式分析了该多模谐振器的谐振特性,并依此推导出其谐振频率与物理尺寸的相互关系。为了满足滤波器的馈电,端口耦合并实现小型化,引入了异面共面波导馈电结构。文中给出了四个谐振模式的分析以及两个通带中心频率和带宽的控制机理,实现了滤波电路的频率和带宽的独立控制。最终实现了中心频率为2.39GHz 和4.34GHz,相对带宽分别为8.8%和13.4%的双通带平面滤波器。该滤波器中心频率和带宽独立设计可控,而且谐振器尺寸大小仅为0.09λg ×0.09λg 。本文所设计的滤波器结构简单、尺寸小,通带间隔离度较高、易加工制作,具有较高实用价值。     

用谐振腔-截止波导技术测量介质谐振器的复介电常数

在TE01n模谐振腔的一个端面中央,开一圆孔,连接一根等直径、适当长度的截止波导,当截止波导中置入介质谐振器时,使含介质段对TE01模呈传输态。介质谐振器的前向波导段用于调节耦合强弱,足够长度的背向波导段则形成匹配电抗终端或置入金属场构成短路终端。这两种安排都能使置入介质谐振器前后的谐振腔产生相当大的谐振长度和Q因子的变化,从而能获得准确的介质谐振器无载Q因子和介电常数。在X频段对陶瓷谐振器进行测量,获得满意的结果。     

矩形波导中圆柱介质谐振器的精确分析

本文分析了一种新型实用的微波滤波器结构:在矩形波导中插入圆柱形介质谐振器。文中将谐振器作为波导中的不均匀性,用模匹配法准确分析了其散射特性。理论结果不仅能计算谐振频率,而且还给出散射矩阵等网络参数。本文的理论分析与实验检测量结果吻合很好。通过理论与实验研究,本文对衬底的作用作出了新的解释。     

Compact Folded Monopole Antenna Excited by a Conductor‐Backed Coplanar Waveguide with Vias

A compact monopole antenna excited by a conductor‐backed coplanar waveguide (CBCPW) is developed for wireless USB dongle applications. The proposed antenna has a compact dimension of 14 mm × 47.4 mm × 3.5 mm, which is suitable for a USB dongle housing. A slotted elliptical patch and a CBCPW with vertical vias are employed to achieve a further size reduction and an improved impedance bandwidth. The measurement result demonstrates that the fabricated antenna resonates from 2.25 GHz to 10.9 GHz, which covers all of the important wireless communication bands, including WiBro (2.3 GHz to 2.4 GHz), Bluetooth (2.4 GHz to 2.484 GHz), WiMAX (2.5 GHz to 2.7 GHz and 3.4 GHz to 3.6 GHz), satellite DMB (2.605 GHz to 2.655 GHz), 802.11b/g/a WLAN (2.4 GHz to 2.485 GHz and 5.15 GHz to 5.825 GHz), and ultra‐wideband (3.1 GHz to 10.6 GHz) services. The radiation characteristics of the proposed antenna when attached to a laptop are tested to investigate the influence of the keypad and the LCD panel of the laptop.     

一种新型宽带圆极化介质谐振器天线设计与实现*

设计了一种宽带圆极化介质谐振器天线,为一种鼠笼形的宽带一分四90毅相移功分微带馈电网络,采用缝隙耦合对介质谐振器顺序旋转耦合馈电。天线结构紧凑、加工简单,仿真和实测结果吻合良好,其阻抗带宽和低于3dB的轴比带宽重叠部分在1.09 GHz-1.83GHz、为50.7%。增益大于3dB 及轴比小于3dB 的波束宽度均达到90°。天线工作频率覆盖四大导航系统,包括中国的北斗系统、美国的GPS 系统、欧洲的伽利略(GALTLEO)系统和俄罗斯的格洛纳斯(GLONASS )系统的频段,天线可应用于全球卫星导航定位系统和无线宽带通信系统中。