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1.
Possible high-Q circuits based on a new crosstie overlay slow-wave structure are proposed for monolithic microwave integrated circuits. Configurations and results of slow-wave factors are presented. This structure is used for construction of a frequency-selective reflector with a compact size. The effect of loss is considered.  相似文献   

2.
A novel /spl pi/-bridged photonic bandgap (PBG) power/ground planes is proposed with ultra-broadband suppression of the ground bounce noise(GBN) in the high-speed printed circuit boards. The S-parameters of the proposed low-period structures show that the novel uniplanar compact photonic bandgap (UC-PBG) structures could omni-directionally suppress the GBN in RF/analog circuits and digital circuits. The high omnidirectionally suppressions of the GBN for the proposed structure are validated both experimentally and numerically in the noise bandwidth from 300MHz to 6GHz, almost the whole noise band.  相似文献   

3.
The analysis is presented for a microstrip feed proximity coupled monofilar Archimedean spiral four-element antenna array. Interactions between the microstrip corporate feed and the radiating elements are rigorously included. Results demonstrate that circular polarization can be achieved with proper spiral arm length. Polarization of either sense is controlled by the location of the feedline. The 3-dB axial ratio (AR) and voltage standing wave ratio (VSWR) bandwidths are 9%. The antenna is small (2R/λ0=0.33) and the interelement spacing is 0.51λ0. The microstrip feed produces a completely planar antenna system, which is compatible with microwave integrated circuits (MIC) and monolithic microwave integrated circuits (MMIC)  相似文献   

4.
提出一种地平面刻蚀共面紧凑型微波光子晶体(PBG)的共面波导结构,介绍了微波光子晶体的基本单元结构,并设计出具有90°弯折的共面波导样品.使用矢量网络分析仪测试该结构的散射参数,测量结果显示,其传输特性比普通的共面波导在高频部分具有较大的提高.同时,相比于传统的三维微波光子晶体,该结构具有导体损耗小,加工工艺简单,便于应用于光电封装和单片微波集成电路的特点.
Abstract:
A novel coplanar waveguide using coplanar compact microwave photonic-handgap (PBG) structure is proposed. The basic unit of microwave PBG structure is introduced and a waveguide sample with a 90 degree break is designed. Testing results obtained through vector network analyzer display an obvious promotion in transmission parameter, especially in the high frequency part. Meanwhile, compared with the common 3-dimension microwave PBG structure, this structure with a low conductor loss can be processed with standard planar fabrication technology, which makes it applicable in opto-electronic package and monolithic microwave integrated circuit (MMIC).  相似文献   

5.
针对传统基片集成波导(substrate integrated waveguide,SIW)功分器设计中宽带化和小型化不易兼顾的问题,提出了一种基于慢波SIW(slow-wave SIW, SW-SIW)的功分器. 采用微带折线构成的慢波结构单元加载于SIW金属表面上,代替传统SIW连续的金属表面,与同尺寸的SIW相比,SW-SIW的截止频率下降了40%,能够实现横向尺寸的缩减,尤其当SW-SIW达到与SIW相同的相移量时,SW-SIW所需纵向尺寸更小. 所提出的基于SW-SIW的功分器在具有较宽带宽的同时实现了器件尺寸的减小. 通过测试结果可得,该功分器在8.25~12.8 GHz频带内的反射系数|S11|相似文献   

6.
光子带隙(Photonic BandGap, PBG),是指人造的周期性电介质结构,它使得在一定频率范围内的电磁波是禁止传播的,而单平面紧凑型光子带隙结构(UC-PBG)是一种以微带基片为载体的周期性平面光子带隙结构。该文用UC-PBG结构置换标准矩形波导窄边,可在UC-PBG结构的谐振频率点附近将TE10模转变成准TEM模。通过对整个系统进行仿真计算,证实了此方法切实有效,在Ku波段转换带宽达到450 MHz。  相似文献   

7.
The performances of two microwave sources used to produce fluorine atoms by dissociation of SF6for a CW hydrogen fluoride chemical laser are compared. The first device, large microwave plasma (LMP), is a slow-wave structure while, the other (surfatron) excites a plasma surface wave. Their performances, as far as electrical and chemical efficiencies are concerned, are quite similar when operated at the same microwave power level. However, the slow-wave structure can sustain higher microwave power, providing larger laser output power, while the surfatron has much smaller dimensions, allowing for a more compact laser system.  相似文献   

8.
A novel planar PBG structure for size reduction   总被引:2,自引:0,他引:2  
A novel planar photonic band-gap (PBG) scheme is presented for size reduction, the proposed structure can be considered as a kind of distorted uniplanar compact-PBG (DUC-PBG) while being even more compact in size. Its design is detailed in this letter, and several experimental results are presented, the properties of the proposed DUC-PBG are examined, as compared with that of the conventional UC-PBG.  相似文献   

9.
一种新型一维微带PBG单元结构   总被引:1,自引:1,他引:0  
通过对传统二维微带 PBG 结构的研究,针对微带线的传播常数是微带线相对于接地板上周期孔眼的两个主轴的位置和方向的敏感参数而不能根据实际情况任意布线的缺点,提出了一种新型一维微带 PBG(photonic bandgap)单元结构及其等效 L-C 电路模型。本文提出的 PBG 传输线可以应用于微波集成电路中,能够减小电路尺寸,且可以抑制高次谐波的产生。  相似文献   

10.
A novel broadside coupled stripline coupler with a uniplanar compact photonic bandgap (UC-PBG) structure is presented. Construction of the coupler is based on a stripline with two-dimensional periodically etched ground plane. The slow-wave phenomenon has been predicted and observed. Numerical and experimental investigations show an enhanced backward coupling effect. The usefulness of both phenomena in the coupler construction has been verified experimentally.  相似文献   

11.
The single-layer reduction (SLR) model computes the normalized phase constant (β/β0), dielectric loss (αd), and conductor loss (αc) for the Schottky contact slow-wave microstrip (SCSM) line with accuracy about 2.0% for β/β0, and within 0.01 dB/mm for the total loss (αtdc) as compared against the experimental results. The SLR model has been further used to analyze the normal and abnormal characteristics of a proposed Schottky contact suspended slow-wave microstrip (SCSSM) line with 22% increase in β/β0 over the normal SCSM line. The SCSSM line could be useful in the lower range of RF for the development of compact components  相似文献   

12.
周焱  苏东林  翟禹 《微波学报》2005,21(3):32-35
针对微带电路频率响应多谐性的影响,本文研究应用UC-PBG结构集成到微带电路的设计中,从而削弱高次谐波对微带传输线的影响,提高微波滤波器的频带特性,并通过设计测试C波段PBG带通滤波器加以验证.  相似文献   

13.
We describe the microfabrication and band structure of large scale three-dimensional (3D) photonic bandgap (PBG) materials based on self-organizing templates. The simplest of these templates is an fcc lattice of close-packed, weakly sintered spheres. Other templates include hcp and hexagonal AB2 self-organizing photonic crystals. These photonic crystals may be converted into PEG materials by partially infiltrating the template with high refractive index semiconductors such as Si, Ge, or GaP and subsequently removing the template. The resulting “inverse opal” structure exhibits both a photonic pseudogap and a complete (3D) PBG in the near visible spectrum, spanning up to 15% of the gap center frequency. The local density of states (LDOS) for photons exhibits considerable variation from point to point in coordinate space and reveals large spectral gaps even in the absence of a PEG in the total density of states. These gaps in the LDOS may lead to novel effects in quantum and nonlinear optics when active atoms or molecules are placed within the PBG material. These effects include anomalous, low threshold nonlinear response, collective atomic switching, and low-threshold all-optical transistor action. When an optically birefringent nematic liquid crystal is infiltrated into the void regions of the “inverse” opal PBG material, the resulting composite material exhibits a completely tunable PBG. In particular, the 3D PBG can be completely opened or closed by applying an electric field which rotates the axis of the nematic molecules relative to the inverse opal backbone  相似文献   

14.
The design of a coplanar waveguide low-pass filter made of YBa2Cu3O7-δ (YBCO) on an LaAlO 3 substrate is described. Measurements were incorporated into simple models for microwave CAD analysis to develop a final design. The patterned and packaged coplanar waveguide low-pass filter of YBCO, with dimensions suited for integrated circuits, exhibited measured insertion losses when cooled in liquid nitrogen superior to those of a similarly cooled thin-film copper filter throughout the 0 to 9.5 GHz passband. Coplanar waveguide models for use with thin-film normal metal (with thickness either greater or less than the skin depth) and YBCO are discussed and used to compare the losses of the measured YBCO and copper circuits  相似文献   

15.
An analysis is presented for a microstrip-feed proximity-coupled ring antenna and a four-element array. Interactions between the embedded microstrip feed and the radiating element(s) are rigorously included. Results demonstrate that circular polarization of both senses can be achieved with a ring antenna with proper design of two inner stubs located at angles of ±45° with respect to the feedline. Theory and experiment demonstrate an axial ratio 3-dB bandwidth of 1% and the voltage standing wave ratio (VSWR) <2 bandwidth of 6.1%. The axial ratio bandwidth is typical for a microstrip antenna with perturbations, while the VSWR bandwidth is larger than for the circular or rectangular patch with perturbations. A mutual coupling study between two elements shows that the axial ratio is less than 2 dB for interelement spacing greater than 0.55λeff, while the VSWR <2 for all spacings considered. A comparison between theory and experiment is provided for a 2×2 element array. The benefits of sequentially rotating the antenna elements in an array environment are presented. The axial ratio and VSWR bandwidths are both increased to 6.1% and 18% for a four-element array. A single-element antenna with two orthogonal feeds to provide both senses of polarization is demonstrated. The ring antenna is small (D/λ0=0.325), the substrate thickness is thin (H/λ0~0.035), and the microstrip feed produces a completely planar antenna system, which is compatible with microwave and millimeter integrated circuits (MICs), and monolithic microwave integrated circuits (MMICs)  相似文献   

16.
A GaAs MCM power amplifier has been developed for 1.9-GHz digital cordless telephones. Power-added efficiency of 40.2% and P1dB of 22.2 dBm have been obtained at drain supply voltage of 3.6 V. Adoption of the multilayer MCM structure, i.e., multilayer microwave integrated circuits (MuMIC), and on-chip ferroelectric capacitors successfully reduced the GaAs total chip area to be 1.1 mm2. We consider that the MuMIC is the most effective candidate for high frequency circuits  相似文献   

17.
A compact tune-all bandpass filter is presented. This electronically tuned filter is based on series-coupled slow-wave resonators. It allows wide simultaneous and continuous tunings of centre frequency (+/-15% around 0.7 GHz) and bandwidth (from 50 to 100 MHz) with insertion loss IL<5.4 dB and return loss RL>11 dB. This two-pole bandpass filter exhibits also a very small surface of only 7.3times10-3 lambda0 2 and a -20 dB stop-band that extends up to 10 GHz  相似文献   

18.
Dielectric properties of both Nd1.9Ba1.1Cu 3O7+δ (NBCO-213) and Pr1.14Ba1.86Cu3O7-δ (Pr-rich PBCO) single crystals have been examined at low temperature. These materials have good lattice matching to high-Tc superconductors (HTS), but they are conductive at room temperature. Below 80 K, they are insulators with low dielectric constants, ε τ below 25, and low dielectric loss tan δ below 0.1 at 100 kHz. The value of ετ is suitable for insulators in integrated circuits using strip line widths of 10 μm order, providing short delay time, no excitation of surface wave, and low radiation loss. The value of tan δ is comparable to loss of superconducting surface resistance above 100 GHz. These results indicate the applicability for the insulator layers in multilayer superconducting electronic devices such as Single Flux Quantum (SFQ) circuits operated at high speed  相似文献   

19.
In this letter, a rectangular waveguide to conductor backed-coplanar waveguide electromagnetic transition suitable of operating at sub-millimeter wave frequencies is demonstrated. The dipole based transition is fabricated using InP monolithic microwave integrated circuit technology. The compact transition eliminates wire-bonding problems (return loss and insertion loss) and is suitable for direct integration of sub-millimeter wave monolithic integrated circuits. Measured transition loss of $sim$ 1 dB has been achieved in the frequency range of 340 to 380 GHz.   相似文献   

20.
一种新型的基于UC-PBG基底的微带天线   总被引:1,自引:0,他引:1  
郭勇  李一玫  黄亮 《电波科学学报》2006,21(5):768-770,776
提出了一种新的基于平面光子带隙(UC-PBG)结构的微带天线,在基底上开了一个凹槽,天线贴片位于槽的底部,设计天线的工作频率落在光子晶体的禁带之内.通过对该结构进行数值仿真,证实了该设计在抑制表面波,提高增益及效率和改善辐射方向性等方面的有效性.  相似文献   

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