基于介质片加载实现MIMO介质谐振器天线解耦

提出了一种通过在介质谐振器(DR)上表面侧边加载介质片(DS)来实现1×2 MIMO介质谐振器天线(DRA)解耦的新方法。1×2 MIMO DRA采用双层介质基板结构以优化阻抗匹配特性和辐射特性,两DR的边到边间距为0,天线工作在毫米波频段。所加载的DS使得DR内的场重新分布并向DS加载区域以及DS内集中,从而减弱耦合到另一DR单元的场强以实现解耦效果。基于ANSYS HFSS的仿真结果表明天线的-10 dB阻抗匹配带宽为25.6%(22.75～29.43 GHz),带内最大实现了30 dB的隔离度的增强。     

一种采用同轴探针馈电的半球形介质谐振天线

介质谐振天线具有一些突出的优点,如:体积小、效率高、带宽很宽等。本文仿真设计了一种采用同轴馈电的半球形介质谐振天线,并研究了其探针长度、馈电点位置和介电常数对天线性能的影响。     

Ku波段介质锁相抗振频率源研制

提出了一种混频介质锁相的方案,对Ku波段的发射信号进行一次混频锁相得到Ku波段的本振信号,实现了本振信号与发射信号的相位同步。电路设计采用了低噪底鉴相芯片和自主设计的低相噪Ku波段介质压控振荡器(DRVCO)。结构设计中充分考虑抗振动性能,并用ANSYS软件对结构进行力学仿真,达到很好的抗振动效果,组件外形尺寸为110mm×65mm×13mm。测试结果表明,静态下该Ku波段频率源输出功率12dBm,杂波抑制比≥70dBc,相位噪声-91dBc/Hz/@1kHz,-105dBc/Hz@10kHz;振动条件下1kHz、10kHz处相位噪声恶化不超过3dB。     

Full-Wave Analysis of Monopulse Dielectric Lens Antennas at W-band

Lens antenna is a good substitute for the Cassegrain antenna at millimeter-wave frequencies, especially at W-band. On one hand, the antenna design, which is bulky and heavy at low frequencies, becomes compact and light-weighted at W-band. On the other hand, without the blockage caused by the sub-reflector and the feed horns which are unavoidable in a Cassegrain antenna, the lens antennas show better radiation characteristics. In this paper, several lens antennas fed by metal horns are analyzed using a full-wave method-finite element method based on the weak form of the Helmholtz equation (WF-FEM). Numerical results show that the lens antennas presented have low side lobe level (SLL), and good sum and difference performances.     

Design and Analysis of Circularly Polarized Dielectric Resonator Antenna

Wireless Personal Communications - The paper presents a novel method for the improvement in the bandwidths by mode merging of the circularly polarized dielectric resonator antenna (CPDRA). The...     

The Trapezoidal Dielectric Resonator Antenna

The operational concepts of the trapezoidal dielectric resonator antennas (DRAs) are presented and their performance is studied theoretically and experimentally. The rectangular parallelepiped is a special case of the more general trapezoid and therefore a comparison between both is useful in order to highlight their similarities and differences. It is shown in this paper that the inverted trapezoidal DRA exhibits a significantly larger impedance bandwidth than the rectangular parallelepiped, while the rest of their properties remain similar. Based on that, two versions of a probe-fed wide-band linearly polarized (LP) DRA are designed by combing the resonances of the first two lower-order modes of the trapezoidal DRA. The resulting impedance bandwidth exceeds 55% $(S _{11} ≪ -10~{rm dB})$ and the patterns are broadside with low cross-polarization. The antennas are simple to fabricate and they can be easily made to be mechanically stable. The numerical analysis was performed with a commercially available FEM solver and an in-house developed finite-volume-time-domain (FVTD) code. The measurements confirmed the results of the simulations.      

加载介质覆盖层的圆柱共形微带天线的全波分析

基于严格的全波方法分析计算了介质薄层覆盖下由探针激励的圆柱共形微带天线的输入阻抗和辐射方向图.首次详细地推导出了此结构下适于数值计算的微带帖片上的表面电流形式,并通过矩量法求解电场积分方程得到感应电流的分布.最终,通过数值结果揭示出了覆盖介质层对天线特性的影响并且与已发表文献及其他数值方法的结果进行对比,证明了方法的正确性.     

Measurement of Low-Loss Dielectric Materials Using Dielectric Rod Resonator

To obtain the complex permittivity of low-loss dielectric materials at 60 GHz, a measurement method is developed. Using a dielectric rod resonator excited by a dielectric waveguide, effective conductivity of conducting plates for short circuiting the resonator is determined. The complex permittivity of the dielectric rod is determined by the resonant frequency and unloaded quality factor of the TE_0m1-mode resonator. Moreover, the complex permittivity of single crystal sapphire, polycrystalline ceramics, and cordierite has been investigated in virtue of numerical simulation. For all the measured specimens in this study, the proposed method is seen to provide much better accuracy for values.     

Dielectric Patch Resonator and Antenna

This paper presents an overview of dielectric patch(DP) antennas developed in recent years.The employed DP resonator composed of a DP and a bottom substrate is analyzed comprehensively here,enabling the easy realization of a quasi-planar DP antenna. It combines the dual advantages of the conventional microstrip patch(MP) antenna and dielectric resonator(DR) antenna in terms of profile, gain,bandwidth, radiation efficiency, and design freedom.Furthermore, the DP antenna inherits the multi-mode ch...     

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。     

UHF微带裂环介质谐振器FET振荡器分析

本文提出了微带裂环介质谐振器FET振荡器电路,分析了FET电路和微带裂环谐振器的特性,最后给出设计这种振荡器的频率温度稳定性考虑与优化方法.     

X波段介质振荡器的设计

研究了一种具有较宽机械调频范围和较低相位噪声的x波段介质振荡器设计方法.利用介质谐振器法对三种型号的介质谐振器(DR)材料进行了精确的测试,得到了其介电常数εr和损耗角正切值tanδ以及DR的谐振频率.利用仿真软件建立微带线与谐振器耦合模型,通过仿真提取其S2P文件.选用GaAs FET ATF26884作为电路中的放大器件,使用生成的S2P文件建立介质振荡器(DRO)电路模型,调整耦合段和输出匹配微带线的长度,得到较低的相位噪声.测试证明输出信号的相位噪声在偏离中心频率100 kHz处小于-100 dBc/Hz.     

介质谐振器特性的有限元计算

本文应用有限元方法分析和计算了置于空气和不均匀介质中的圆柱形介质谐振器的谐振频率,以及介质谐振器与微带线的耦合参量。计算结果与现有文献的计算结果和实验结果相当吻合。     

Ka波段介质谐振器的研究

介质谐振器由于具有体积小、损耗低等优点,得到了越来越广泛的应用.设计了一款Ka波段介质稳频振荡器,振荡器中集成了介质谐振器用于选频.通过采用合适的介质振荡子及适当尺寸的金属屏蔽腔,使介质谐振器谐振在Ku波段,再通过单片进行倍频放大,从而得到Ka波段信号.介绍了介质振荡子的选取及参数计算.并以此为根据作为介质谐振器的设计原则,最后得到的Ka波段信号输出频率(fo)为38.22 GHz,输出功率(Po)为7.38 dBm,相位噪声为-80 dBc/Hz@100 kHz.     

Highly Stable Dielectric Resonator FET Oscillators

The long-term frequency drift of GaAs FET oscillators with temperature has been analyzed theoretically and experimentally in view of stabilization using dielectric resonators. It was found that the dielectric material stability and quality factor should be within certain limits, and, in addition, that the resonance frequency over the temperature characteristic should be quite linear. Such a material has been developed on the basis of BaTi/sub 4/O/sub 9/ and Ba/sub 2/Ti/sub 9/O/sub 20/ , and ultra-stable DRO's with frequency drifts of around +- 100 kHz for -50 to 100°C at 11 GHz (ap +- 0.06 ppm/K) have been realized.     

Wideband Circularly Polarized Dielectric Resonator Antenna

A circularly polarized quadruple strip feed cylindrical dielectric resonator antenna utilizing a pair of 90deg hybrid couplers is investigated experimentally. The antenna is shown to deliver an impedance bandwidth (S₁₁ < -10 dB) of 34.5%, from 1.75 to 2.48 GHz, and an axial-ratio bandwidth (AR < 3 dB) of 25.9%, from 1.65 to 2.14 GHz. The gain and radiation patterns are found to be stable within the passband.     

Double Dielectric Resonator (Correspondence)

Equations are derived from which the resonant frequencies of the double dielectric resonators can be calculated taking into account the influence of the conducting walls of the waveguide or the strip line. A comparison between theoretical and experimental results is also given.     

4千兆赫介质谐振器振荡器

本文叙述了介质谐振器作为加载带阻滤波器稳频的基本原理,介绍了4GHz介质谐振器振荡器.该振荡器在-40℃到+55℃范围内,频率稳定度在2ppm/℃左右,在+55℃下连续工作8小时,频率漂移一般在50kHz以内,振荡器的输出功率在10mW左右.该振荡器曾在国际卫星通迅公司5号星电视传输试验中作接收系统的本振源,使用良好.