Spectral Domain Analysis of an Open Slot Ring Resonator

A full wave analysis of an open slot ring resonator on a dielectric substrate is presented. It is based upon Galerkin's method in the Hankel transform domain. The computed resonant frequencies for several slot widths agree well with the experimental values on alumina substrate with epsilon/sub r/= 9.6 in the 26-37-GHz frequency range.     

Spectral Domain Analysis of an Elliptical Microstrip Ring Resonator (Comments)

Along with the above paper several other papers have been published recently by Sharma and his co-workers [2]-[3] on the analysis of the resonant frequencies of a microstnp disk using the quasi-static approach. The quasi-static approach has been proven to be incorrect in [4] and [5]. The quasi-static argument on the correction to the resonant frequencies of a microstrip disk is based on some intuitive arguments that are not rigorous. The only thing it predicts correctly is that the resonant frequencies of a microstrip disk should decrease compared to that of a magnetic-wall model. The author may argue that since the correction to the magnetic-wall model is small, any approximate method is viable. However, we have found that the quasi-static correction could be as much as 50 percent in error. Even when this correction is small, if we bother to caIculate it, I think we should calculate it correctly. The author's quasi-static correction has a new twist compared to earlier authors, but when epsilon/sub r/ = 1, it does not differ from the quasi-static correction of earlier work.     

Spectral Domain Analysis of an Elliptic Microstrip Ring Resonator (Short Paper)

The quasi-static capacitance of an elliptic microstrip ring resonator is evaluated with the spectral domain technique. The effect of fringing of fields associated with the structure is determined using this capacitance value in terms of the effective eccentricities of the inner and outer ellipses, the effective values of the ratio of the semimajor and semiminor axes, and the effective dielectric constant. The resonant frequency of the even TM /sub c110/ mode, calculated utilizing them, is in good agreement with the experiment. Mode charts for the dominant and higher order even and odd TM/sub cm10/ resonance modes are also presented.     

平行信道串联多环谐振滤波器的箱形波谱响应

对平行信道串联多环谐振滤波器的传输特性进行了理论分析,给出了其光学传递函数公式。在谐振波长为1．55μm情况下,对其滤波特性进行了数值模拟。计算结果表明,选取串联微环数为4、信道与微环间的振幅耦合比率为0．25以及相邻微环间的振幅耦合比率为0．022时,箱形波谱响应即可形成,其3dB带宽约为0．2nm,谐振光的插入损耗约为1．5dB,非谐振光的最小值已接近-150dB。     

宽阻带三模谐振器微带带通滤波器设计

介绍了一种新颖的微带三模谐振器,由该谐振器构成的微带滤波器具有较宽的通带以及较好的带外抑制。对传统的单模微带环形谐振器结构进行优化,使谐振器在通带内具有三个谐振点,并且在通带边缘有四个对称衰减极点。引入的阶梯阻抗谐振单元使得微带三模谐振器具有良好的带外抑制。依据传输线原理对宽阻带三模谐振器进行了分析,并完成了中心频率为1090 MHz的宽阻带带通滤波器设计和加工,其实际测试结果与软件仿真结果具有良好的一致性。     

300 MHz氮化铝轮廓模式谐振器的设计

氮化铝轮廓模式谐振器(CMR)能够满足现代无线通信对单片、多频段、可重构的多频率源的需求,具有很大的应用前景。针对目前无具体单个CMR频点的设计方法,提出了一种结合CMR性能参数的影响因素分析和有限元计算的CMR设计方法。该文对CMR的谐振频率、质量因子、机电耦合系数和动态电阻等谐振器主要性能参数的影响因素进行理论分析得到CMR结构的初始尺寸,再利用COMSOL有限元软件建立CMR几何模型并进行频域求解得到相应的频率-导纳曲线和频率-质量因子曲线;根据仿真结果和理论计算对CMR初始结构尺寸进行优化,并仿真设计了一个氮化铝CMR,其谐振频率为300 MHz,质量因子约为1 010,机电耦合系数约为1.64%。     

Triple Mode Use of a Single Dielectric Resonator

A single dielectric resonator is used for a triple mode operation in filtering and dual band radiation purposes. A high unloaded quality factor over 2300 at 2.43 GHz is obtained simultaneously with both broadside and omni-directional radiation patterns of 7% and 8% bandwidths around 2.47 and 3.36 GHz, respectively. Series of parametric studies are developed to tune the filter's operating frequency range, to enhance its insertion loss and to obtain a sharp filtering skirt behavior. Finally, measurements of both filter insertion loss and antenna return loss, coupling coefficients and radiation patterns are illustrated for further verification.      

A Balun-BPF Using a Dual Mode Ring Resonator

In this letter, a Balun-bandpass filter (BPF) is proposed by using a dual-mode ring resonator. The Balun-BPF is not a simply combined or integrated component of a BPF and a Balun but a single BPF with the balun function. We obtained the proper balanced outputs and two-pole BPF characteristic by symmetrically placing the output ports at lambda/2 distance from each other on the dual-mode ring resonator. The fabricated Balun-BPF has a bandwidth of 40 MHz and an insertion loss of 2.4 dB at a center frequency of 2.45 GHz. The differences between the two outputs are 180-184deg in phase and within 1dB in magnitude. The measured frequency responses agree well with simulated ones.     

激光器线宽对光纤环形谐振腔谐振特性的影响

采用光波场叠加的方法计算了谐振腔光纤陀螺的核心敏感部件———光纤环形谐振腔 (FRR)的传递系数 ,详细分析了激光器光谱线宽对光纤环形谐振腔谐振特性的影响 ,并进一步分析了在一定激光器光谱线宽条件下 ,由光探测器散弹噪声所限制的谐振腔光纤陀螺极限灵敏度和光纤环形谐振腔光路参数之间的关系 ,从而为谐振腔光纤陀螺的优化设计提供了理论基础     

Loop-Gap Resonator: A Lumped Mode Microwave Resonant Structure

Loop-gap resonators are newly developed microwave resonant structures with a field configuration that is intermediate between lumped and distributed. Typical characteristic dimensions are of the order of 1/10 of the resonant wavelength, and typical Q's are of the order of 1600-2000 in the frequency range of 1-4 GHz. Data are presented for Q's and frequencies for a series of resonators of various dimensions and compared with theory. Various coupling and frequency tuning techniques are discussed, and results of experiments are reported. Results of preliminary application of the stictire in microwave filters and oscillators are presented. Loop-gap resonators provide a useful design alternative, it is concluded, to dielectric and surface acoustic-wave resonators at low microwave frequencies.     

某电子厂房洁净空调加湿方式的选择

以某电子厂房净化空调设计加湿方式的选择为例,分析了三种加湿方案的选择过程及使用条件,确定本工程最佳加湿方案。     

新型板条激光器的离轴混合腔模场计算

报道了一种新型双板条离轴混合腔激光器。这种激光器结构通过改变传统的冷却方式和采用特殊的谐振腔设计，将使从第一块介质板条高温一侧出射的激光对称地进入另一块板条的低温一侧，从而可对由于温度分布不均匀造成的波面畸变进行一定程度的自校正，减少热效应的影响，可望提高激光器的输出功率和光束质量。利用快速傅里叶变换（FFT）对这种激光器的近场、远场以及相位等模场特性进行了数值计算。分析了波面畸变对输出光束质量的影响，并与常规双板条激光器进行了比较，结果表明这种新型双板条离轴混合腔激光器可以实现一定程度的波面畸变自补偿，从而获得更好的输出光束质量。     

基于传输矩阵的激光谐振腔模式计算

建立了激光谐振腔往返传输矩阵,通过求解往返传输矩阵的特征值与特征向量,获得了激光谐振腔模式特征.该方法可以用于快速计算同阶贝塞耳函数的所有谐振腔模式和衍射损耗,其结果与Fox-Li数值迭代方式计算结果完全一致.分别就对称谐振腔往返传输矩阵的A2与单程传输矩阵A的特征值及特征向量之间的关系和物理意义,以及非对称谐振腔往返传输矩阵AB与BA的特征值及特征向量之间关系和物理意义进行了分析和讨论,建立了数学表达式,并可以通过改变传输矩阵来提高计算效率.分析了对称共焦腔离散单元数量对光腔模式计算结果的影响,建立了最佳离散单元数量与谐振腔镜片半径的关系表达式,并实现了大菲涅耳系数共焦腔模式的计算.     

基于亥姆霍兹方程的有源非稳腔模式计算方法

提出了一种基于亥姆霍兹方程的有限差分方法用于有源非稳腔的模式计算.从理论上分析了光场传输的有限差分计算方法,并由此出发,建立了针对有源非稳腔模式的数值计算模型.基于这个计算模型,能够较为精确、快速地获得激光谐振腔输出的光场分布.分别给出了空腔条件下和非均匀增益条件下的数值模拟结果,前者还与用快速傅里叶变换法获得的数值模...     

高斯和超高斯型随机相位调制的光腔模式

本文利用空间－频率域相干模式理论对内置高斯或超高斯类型的随机相位调制的腔内模式进行了数值分析。结果表明：在这种随机相位片调制下,通过控制参数,可以在一腔镜上得到部分相干的类超高斯分布的光束,且类超高斯阶次可由相位参数控制;本文还引入新的参量－平整度来描述光束的整体强度分布的特征。     

光纤微球谐振腔回音壁模式光学特性的研究

从麦克斯韦尔方程出发,分析了介质微球谐振腔支持的回音壁模式(WGM)分布,针对光纤微球谐振腔这种实现回音壁模式的方式,进行了理论研究和通信传输实验系统的搭建,并阐明了优化的方向,仿真结果表明,实现激发回音壁模式的耦合与传统光波导谐振腔通信传输系统相比,光纤微球谐振腔的回音壁模式通信传输系统具有更深刻的物理内涵和应用价值。     

基模运转的热稳定定向棱镜谐振腔设计

为了提高军用固体激光器的稳定性,利用g3参数等价腔分析法,设计了一种在高功率 固体激光器热焦距变化较大时能保持稳定的基模运转的免调试定向棱镜谐振腔,理论分析与实验结果基本吻合,满足了军用固体激光器对高功率、高光束质量和高稳定性的要求。     

谐振式光纤陀螺环形谐振腔的偏振问题

谐振式光纤陀螺(R-FOG)中,偏振波动引起的检测信号漂移对陀螺系统的检测精度有重要影响.通过矩阵法,分析系统中光纤耦合器不同偏振本征态(ESOPs)的耦合系数差异,与所引起的系统零偏的关系,得剑其与两个偏振本征态耦合系数以及光纤环形谐振腔参数间的解析表达式.利用该解析表达式,求解系统零偏为极值时,耦合器不同偏振本征态的最佳耦合系数;该最佳耦合系数仅与光纤环形谐振腔的损耗参数有关.通过Matlab软件进行数值拟合,得到不同偏振本征态耦合系数与系统零偏之间的关系曲线.从理论上建立耦合器耦合系数偏振相关引起的噪声模型.利用该理论模型,对已报道的R-FOG开环实验系统中偏振波动引起的系统零偏进行了估算.     

Selection of Crosstalk-Induced Faults in Enhanced Delay Test

Current design trends have shown that crosstalk issues in deep sub-micron can cause severe design validation and test problems. In this paper, we address the problem of enhanced delay test considering crosstalk-induced effects. Two types of crosstalk-induced delay fault model in related works are analyzed according to their relationship to common delay fault models. The difficulties in test generation using these fault models are shown. Based on the discussion, a single precise crosstalk-induced path delay fault model, S-PCPDF model, is proposed for circuits given delay assignment. A target S-PCPDF fault gives information on a sub-path to be sensitized to generate necessary transitions coupled to a critical path. It is then convenient to enhance conventional path delay fault ATPG algorithms to implement ATPG systems for crosstalk-induced path delay faults by adding the constraints on the sub-path. We then propose two approaches to reducing the number of target S-PCPDF faults. One is based on constraints for side-inputs of paths under test. The other is based on pre-specified states during test generation for the critical path. Experimental results on ISCAS89 benchmark circuits showed that the proposed approaches can reduce the number of target faults significantly and efficiently. The CPU time for fault list reduction and test pattern generation is acceptable for circuits of reasonable sizes.Huawei Li received her B.S. degree in computer science from Xiangtan University in 1996, and M.S. and Ph.D. degrees from the Institute of Computing Technology, Chinese Academy of Sciences in 1999 and 2001 respectively. She is now an associate professor at the Institute of Computing Technology, Chinese Academy of Sciences. Her research interests include VLSI/SoC design verification and test generation, delay test, and dependable computing.Xiaowei Li received his B.Eng. and M.Eng. degrees in computer science from Hefei University of Technology (China) in 1985 and 1988 respectively, and his Ph.D. degree in computer science from the Institute of Computing Technology, Chinese Academy of Sciences in 1991. Dr. Li joined Peking University (China) as a Postdoctoral Research Associate in 1991, and was promoted to Associate Professor in 1993, all with the Department of Computer Science and Technology. From 1997 to 1998, he was a Visiting Research Fellow in the Department of Electrical and Electronic Engineering at the University of Hong Kong. In 1999 and 2000, he was a Visiting Professor in the Graduate School of Information Science, Nara Institute of Science and Technology, Japan. He Joined the Institute of Computing Technology, Chinese Academy of Sciences as a professor in 2000. At present, he is a vice-director of the laboratory of information networks. His research interests include VLSI/SoC design verification and test generation, design for testability, low-power design, dependable computing. Dr. Li received the Natural Science Award from the Chinese Academy of Sciences in 1992, the Certificate of Appreciation from IEEE Computer Society in 2001. He is a senior member of IEEE and a senior member of China Computer Federation. He is an editor of Journal of Computer Science and Technology and Journal of Computer-Aided Design & Computer Graphics (in Chinese).     

Mode Selection in Resonators With Conical Reflectors

The characteristics of laser oscillators can be modified toward specific requirements by inserting suitable optical elements in the resonator. We show that replacing one of the resonator mirrors by a conically shaped reflector can lead to a significant increase in the volume of the fundamental mode resulting in improved power efficiency. Alternatively, the first azimuth mode, which is important for various applications, such as high-resolution microscopy, can be selected by inverting the reflector head angle.