共查询到20条相似文献,搜索用时 15 毫秒
1.
慢波微带线的多种不连续性和相邻慢波单元的耦合影响了特征阻抗的准确计算,因此在慢波微带线的设计阶段需要一种手段来提取其特征阻抗。提出一种利用史密斯圆图提取慢波微带线特征阻抗的方法,该方法通过观察慢波微带线的反射系数在史密斯圆图中的图像估计其特征阻抗的大小,并通过反射系数极值计算特征阻抗。以梳状慢波微带线为例检验该方法,特征阻抗的提取结果与利用S参数提取的结果十分接近,从而证明该方法是一种可行的慢波微带线特征阻抗提取方法。 相似文献
2.
Coupled microstrip line theory is applied to analyze planar Ruthroff transmission-line transformers (TLTs). The results demonstrate that the TLT's low frequency response improves as the microstrip line's even-mode impedance increases, whereas the ratio of load impedance to the line's odd-mode impedance controls the high frequency response. Analysis of an approximate model of coupled microstrip lines formed into a spiral leads to a technique for predicting the performance of planar, spiral-shaped, Ruthroff TLTs. Microwave measurements up to 10 GHz are compared with predictions from the model for regular and suspended Ruthroff TLTs fabricated through a multichip-module deposited (MCM-D) process 相似文献
3.
4.
Using a microstrip line employing periodically perforated ground metal (PPGM) on a GaAs monolithic microwave integrated circuit (MMIC), a highly miniaturised and broadband impedance transformer was developed for application to low impedance matching in broadband. Its size was 0.132 mm/sup 2/ on GaAs substrate, which was 2.3% of the one fabricated by a conventional microstrip line. The transformer showed good RF performance over a broadband including ultra-wideband. This is the first report of an on-chip broadband impedance transformer fabricated on MMIC. 相似文献
5.
为了简化方形切角圆极化微带天线单元的设计流程,提出了一种新颖的开槽切角圆极化微带天线单元形式。利用在微带天线单元上开矩形槽的方法,避免了调试切角圆极化单元的谐振频点和轴比时的反复迭代过程,缩短了调试时间。分析了矩形槽的不同宽度和深度对阻抗和轴比的影响,并通过仿真设计出一款性能良好的微带天线单元。单层微带天线单元仿真的最终阻抗相对带宽(S11 <-10 dB)为2. 05% (1. 980 ~ 2. 021 GHz);仿真的最终轴比相对带宽(AR<3 dB)为0. 50%(1. 995 ~2. 005 GHz)。加工了天线单元实物并进行测试,实测的阻抗相对带宽(S11 <-10 dB)为2. 05%(1. 975 ~2. 016 GHz);实测的轴比相对带宽(AR<3 dB)为0. 50% (1. 990 ~ 2. 000 GHz)。实测结果与仿真结果具有良好的一致性,验证了设计的正确性。 相似文献
6.
A stepped impedance filter has been realised on a modified substrate. The change in impedance was achieved by varying the dielectric constant in the substrate while maintaining a constant width of the microstrip. In contrast to conventional stepped impedance filters the impedance is varied by the dielectric constant instead of the microstrip line width. The manufactured filter was measured and compared with an equivalent conventional stepped impedance filter. It is shown that the modified substrate technology could offer an alternative to the standard approach for the stepped impedance filter. In combination with new materials with a high permittivity the technology could also offer a denser package since the microstrip width could be controlled as desired. 相似文献
7.
The electromagnetic field integral equation in the quasi-optical cavity is obtained using the dyadic Green's function. An expression is derived for the input impedance of a single microstrip patch cavity excited by a coaxial probe using moment method. The input impedance of a rectangular microstrip patch is discussed with this method. The result of this paper is similar to that of the microstrip antenna. This paper is of very important value for designing microstrip quasi-optical oscillator. 相似文献
8.
本文利用并矢格林函数获得了准光腔中的电磁场积分方程。利用矩量法导出了被一个轴向电流源激励的单微带贴片腔的输入阻抗的计算公式。利用本方法对矩形微带贴片的输入阻抗进行了讨论。其结果与微带天线很类似。这对设计微带型准光振荡器有重要的参考价值。 相似文献
9.
新型微带缝隙天线的阻抗特性研究 总被引:5,自引:2,他引:5
在互易原理的基础上,用矩量法在谱域内求解一种新型(带盖板的)微带缝天线的输入阻抗,并与通常意义上的微带缝隙天线进行比较,开拓了微带缝隙天线的应用范围。 相似文献
10.
Hong-Twu Chen Horng-Dean Chen Yuan-Tung Cheng 《Antennas and Propagation, IEEE Transactions on》1997,45(11):1581-1583
In this paper, an annular-ring loaded (ARL) spherical-circular microstrip antenna is studied theoretically. The antenna is excited by a coaxial probe. The theoretical formulation is based on full-wave analysis in the spectral domain by using the vector Legendre transform and Galerkin's moment method is used for numerical calculation. Numerical results of the resonance frequencies, input impedance, voltage standing wave ratio (VSWR), and radiation characteristics are presented. It is shown that the impedance bandwidth of the spherical-circular microstrip antenna can be broadened by adding an annular-ring parasitic patch. By comparing to the single circular-patch case the spherical-circular microstrip antenna with an annular-ring parasitic patch has larger minor lobes and larger cross-polarization radiation 相似文献
11.
The electromagnetic field integral equation in the quasi-optical cavity is obtained using the dyadic Green's function. An
expression is derived for the input impedance of a single microstrip patch cavity excited by a coaxial probe using moment
method. The input impedance of a rectangular microstrip patch is discussed with this method. The result of this paper is similar
to that of the microstrip antenna. This paper is of very important value for designing microstrip quasi-optical oscillator.
Supported by the National Science Foundation of China. 相似文献
12.
分析了微带长度及阻抗比对SIR带通滤波器的谐波参数的影响,并利用Angilent ADS仿真软件分别对不同长度及不同阻抗比的滤波器电路进行仿真分析,找出谐波频率随微带长度及阻抗比变化的规律。 相似文献
13.
《Microwave Theory and Techniques》1983,31(8):624-632
Voltage and current cannot be defined uniquely for microstrip except at zero frequency, and therefore microstrip has not been rigorously incorporated into circuit theory. However, in engineering practice, micro-strip exhibits an apparent characteristic impedance, denoted here by ZA, that can be measured. Three methods of measuring ZA were devised and used in measuring three impedance levels of microstrip. These methods are described and experimental results presented. The measurements of ZA were found to be consistent with the power-current characteristic impedance definition of the approximate longitudinal-section electric (LSE) model of nricrostrip. Simple approximate formulas for representing ZA are also discussed. 相似文献
14.
提出并设计了两种新型的微带线-槽线转换接头,分别由微带T型分支、槽线T型分支构成,接头可以很容易地实现低特性阻抗(Z0)微带线至高特性阻抗(近似于4Z0)槽线之间的转换.实际制作了X波段槽线型背对背接头并进行了测试.结果表明,在36%的频带内插入损耗小于1.75dB. 相似文献
15.
《Microwave Theory and Techniques》1980,28(3):215-218
The coupling between a microstrip and a distributed IMPATT diode was investigated in a field analysis. An effective wave impedance in the traveling wave diode can be defined as the ratio of the space-average transverse electric and magnetic fields. This impedance is related to an effective characteristic impedance by a geometry factor. Thus the coupling question is reduced to the coupling between two transmission lines. In addition the diode is modeled in an equivalent transmission line. The equivalent series impedance and shunt admittance are found. The shunt admittance is approximately equal to the admittance (per unit length) of a discrete diode of identical doping profile. The coupling analysis presented here seems applicable to microstrip interfaces to traveling wave structures other than the IMPATT diode. 相似文献
16.
超薄(或说零厚度)微带线是微波电路设计的重要组成部分。基于矩量法,推导了零厚度微带线电磁参量的公式,计算了微带线的特性阻抗和相应的等效介电常数,探讨了微带线的准静电边缘效应和两条微带线间的近端串扰问题。计算结果与已有结果相比较,一致性良好。 相似文献
17.
提出了利用微带天线的宽带输入阻抗模型进行有源集成天线的设计方法以预测有源集成天线(AIA)的辐射特性和谐波特性.谐波平衡法被用于得到AIA的谐波特性和阻抗模型的端口电压.然后端口电压作为激励源计算天线特性.实验结果显示该方法可以简单有效进行有源集成天线设计. 相似文献
18.
The impedance bandwidth of series-fed arrays of microstrip patch radiators can be increased dramatically through the use of loading on the microstrip feed line. A technique is described whereby periodic loading with capacitive stubs results in a constant Bloch wave characteristic impedance 相似文献
19.
传输线模型是分析微带天线的一种最简单的方法,但其未将导体的特性参数考虑到天线的分析中去,针对这一缺点,为研究超导体的表面阻抗对高温超导微带天线输入阻抗和谐振频率的影响,把导体特性对天线的影响看作一种微扰来处理,对传统的传输线模型进行了修正,并通过与谱域矩量法相比较,验证了修正后方法的有效性.进而利用修正后的方法计算分析了高温超导矩形微带贴片天线的输入阻抗和谐振频率,给出了关于高温超导微带天线输入阻抗和谐振频率的若干结论. 相似文献
20.
The possibility of using a microstrip patch antenna as a standard transmitting or receiving antenna is discussed. The intrinsic properties of the substrate used for the antenna are determined by careful impedance measurements. Experimental results indicate that the transmitting characteristics of a microstrip antenna can be theoretically determined from its geometry. The microstrip patch antenna discussed is physically small (20-cm2 for 450 MHz) and can be well matched to a 50-Ω power delivery system (SWR=1.17) 相似文献