Dual-mode stepped-impedance ring resonator for bandpass filterapplications

It is well known that two orthogonal resonant modes exist within a one-wavelength ring resonator. In this paper, we focus on a ring resonator possessing an impedance step as a form of perturbation. A convenient analyzing method for obtaining the resonance characteristics of this resonator structure is presented. Furthermore, generation of attenuation poles obtained by the dual-mode ring resonator is discussed. In addition, a filter design method based on this resonator is explained, followed by experimental results, which prove the validity of the proposed design method     

Novel type of fibre-optic ring resonator

A fibre-optic ring resonator with highly wavelength-selective input reflection coefficient was realised by introducing a small local reflection in the ring. The influence of the local reflectivity on the input reflection coefficient is demonstrated. Maximum values for the input reflectivity and finesse are 55% and 10, respectively, using a fibre directional coupler (FDC) with a coupling ratio of 30%/70%.     

A nano-plasmonic HMIM waveguide based concurrent dual-band BPF using circular ring resonator

This article analyzes the transmission line characteristics of plasmonic hybrid metal insulator metal (HMIM) waveguide, circular ring resonator (CRR) based dual-band band-pass filters with two transmission poles in both pass-bands in the optical regime using coupled line feed. The transmission line characteristics of an HMIM waveguide, such as characteristic impedance (ZPV), effective refractive index (neff) and propagation length (Lspp), have been obtained by using full wave simulation. Using basic HMIM slot waveguide, a CRR with periodic loading of double- and triple-ring CRR is numerically analyzed. Two input ports have been used for excitation, which are located at the separation of 180° positions along the CRR, and are coupled with the ring by parallel coupled lines, producing the dual pass-bands with the synchronous excitation of two transmission poles. The proposed double-ring dual-band band-pass filter (DR-DB-BPF) offers 35 dB extinction ratio (ER), 299.69 nm free spectral range (FSR) and narrow band full width half maximum (FWHM) of 78.057—112.43 nm. The triple-ring DB-BPF (TR-DB-BPF) has 22.5 dB ER, FSR of 292.18 nm and FWHM of 42.751—59.58 nm. The proposed filters are very useful in the development of dual-band filters for electronic photonic integrated circuits (EPICs), as the optical signals are filtered at two wavelengths simultaneously.     

微波谐振腔湿度测量同轴环耦合设计与实现

基于微波谐振腔汽轮机内流动湿蒸汽湿度的测量原理,分析了微波谐振腔及同轴线小环耦合的场结构分布,设计出两端带栅网结构的湿度传感器.采用HFSS型微波软件对湿度传感器进行了建模仿真,由此得到场分布及S参数曲线图,以此设计出湿度传感器的结构尺寸.仿真结果表明,该微波谐振腔传感器工作在TE011模式下,谐振频率为9.58 GHz,其Q=1 198,适合作为测试流动湿蒸气的传感器.与采用矩形波导和谐振腔的孔耦合相比,这种新型同轴线耦合装置体积小,对汽轮机设备的开口也小,实用性也强.     

保偏SiO_2光波导环形谐振腔温度特性研究

利用低压化学气相淀积(LPCVD)技术研制了Si基SiO2保偏光波导环形谐振腔,通过测试不同温度下的谐振曲线,得到了谐振腔双折射率差温度系数,进而利用琼斯矩阵法建立了谐振腔温度特性分析模型,分析了温度波动对谐振腔两个偏振态输出谐振曲线的影响。分析表明,研制的Si基SiO2保偏光波导环形谐振腔芯片具有较好的温度特性,能在较大温度范围内避免温度波动带来的两个偏振态谐振谷的重叠现象。     

Tunable filters based on an SOI nano-wire waveguide micro ring resonator

Micro ring resonator(MRR) filters based on a silicon on insulator(SOI) nanowire waveguide are fabricated by electron beam photolithography(EBL) and inductive coupled plasma(ICP) etching technology.The cross-section size of the strip waveguides is 450×220 nm2,and the bending radius of the micro ring is around 5μm.The test results from the tunable filter based on a single ring show that the free spectral range(FSR) is 16.8 nm and the extinction ratio(ER) around the wavelength 1550 nm is 18.1 dB.After thermal tuning,the filter’s tuning bandwidth reaches 4.8 nm with a tuning efficiency of 0.12 nm/℃Meanwhile,we fabricated and studied multi-channel filters based on a single ring and a double ring.After measurement,we drew the following conclusions: during the signal transmission of multi-channel filters,crosstalk exists mainly among different transmission channels and are fairly distinct when there are signals input to add ports.     

SOI基微环谐振可调谐滤波器

采用电子束光刻和ICP刻蚀等工艺制作出基于SOI纳米线波导微环谐振滤波器。滤波器微环半径为5μm左右,波导截面尺寸为(350nm～500nm)220nm不等。测试结果表明,波导宽度为450nm时器件性能最为理想,其自由频谱宽度为16.8nm,1.55μm波长附近的消光比为22.1dB。通过对微环滤波器进行热光调制,在21.4℃～60℃温度范围内实现了4.8nm波长范围的可调谐滤波特性,热光调谐效率达到0.12nm /℃。同时,研究了基于单环和双环的多通道上下载滤波器,实验结果表明多通道滤波器的信号传输存在串扰,主要是不同信道之间的串扰,尤其在信号上载时,会在相邻信道产生较大串扰。     

A rectangular beam waveguide resonator and antenna

A closed microwave resonator is derived from the beam waveguide of rectangular symmetry. The resonator is essentially a metal box with one curved wall and approximate dimensionslambda/2bylambda/3by20lambda, wherelambdais the free-space wavelength. Each beam waveguide mode is shown to resonate at a distinct frequency. When apertures are cut in one wall of the resonator a line source antenna is formed. Since then = 0andn = 1beam modes have field distributions which are, respectively, a Gaussian and the derivative of a Gaussian, the radiation patterns produced are of interest in monopulse radar and tracking. A 9 GHz resonator antenna was built, and its measured radiation patterns confirm the theory.     

A new inverted F antenna with a ring dielectric resonator

A new antenna combining the use of a ring dielectric resonator (DR) and an inverted F antenna (IFA) is proposed and investigated experimentally. In this application, the DR not only fills the role of a dielectric coating, but also serves the function of a radiator. The measurements of input impedance, return loss, and radiation pattern for both the IFA with the DR (IFA-DR) and the wire IFA (WIFA) are conducted at the S band. The measured data demonstrate that the IFA-DR operates in multiple resonance modes unlike a WIFA. Compared with the WIFA, the one proposed here incorporating a ring DR and an IFA is more attractive in having a smaller size and a larger impedance bandwidth     

带有环形谐振器L型弯折光子晶体波导性能的研究

本文提出了一种带有环形谐振器的L型弯折光子晶体波导结构,利用时域有限差分法研究了该波导电磁波的传输性能.分析结果表明:该结构具有宽频带、高传输率等特点,在光通讯器件制作、光子晶体集成化等方面具有潜在的应用价值.     

A finesse-enhanced Er-doped-fiber ring resonator

A two-coupler-type Er-doped-fiber ring resonator that compensates for the round-trip optical loss by optical amplification is proposed. Also proposed is a mode-filtered heterodyne method for resonant-linewidth measurements which does not demand narrow-linewidth light sources, but uses the beat noise between two uncorrelated lights filtered by the resonator passband. With this method, a finesse ⩾500 and a resonant linewidth ⩽17 kHz were confirmed from the Er-doped fiber ring resonator. The ring resonator was operated as a high-resolution optical spectrum analyzer     

基于电增益环腔选频特性的小型光电振荡器

为了进一步提高光电振荡器的实用性,提出了一种基于耦合型电增益环腔的小型化光电振荡器。利用电功分器和放大器构成电增益环腔,其梳状滤波效应可以有效对光电振荡器进行模式选择,结合直接调制半导体激光器,单模光纤和光电检测器,有效实现了小型化光电振荡器。理论上分析了电增益环腔的基本原理,并且通过仿真进行了验证。实验中获得了中心频率为12.624 GHz的微波信号,其相位噪声为-102 dBc/Hz@10 kHz。该方案在结构简单的条件下可以得到质量较高的射频信号,可以作为光电振荡器实用化的一种解决方法。     

A wide-FSR waveguide double-ring resonator for optical FDMtransmission systems

A wide free-spectral-range (FSR) waveguide double-ring resonator (DRR) is investigated for use in optical frequency-division multiplexing (OFDM) transmission systems. It consists of two ring resonators with different radii and three directional couplers. The FSR is determined by the least common multiple of the FSRs of the two ring resonators. In order to determine the parameters of the DRR, transmission equations of the DRR, which have different radii, are derived by using the scattering matrix. The dependence of the transmittance characteristics of the DRR on the amplitude coupling coefficients of directional couplers and on the propagation loss of the ring waveguides is studied. The design guidelines for OFDM transmission systems are described     

精细调谐电增益环腔光电振荡器

为了有效实现光电振荡器(OEO)输出频率精细调谐 ,提出了一种基于电增益环腔(EGRR)的OEO。利用放大器、 滤波器和移相器构成可调谐EGRR,通过改变EGRR内信号的相位等效实现 环腔长度的改变,得到不同 频率的射频(RF)信号,RF信号与OEO产生的自由振荡信号电注入锁定,输出信号 的频率由锁定EGRR输出频 率的OEO模式决定,相位噪声由OEO决定。在简单结构实验的条件下,有 效实现了OEO输出频率精细调谐。实验结果表明,当光纤长为2km、EGRR长为0.5m时,得到 了频率为11.3GHz、边模抑制比(SMSR)为 48dB、可调谐范围为239MHz、调谐最小步长 为100kHz和相位噪声为－99dBc/Hz@10kHz的RF信号。     

计算波导加载腔外Q值的新方法

本文基于边界元法,提出了一种新的简单有效的计算速调管输出系统波导加载腔外Q值的方法。计算了一种矩形波导加载矩形谐振腔的常见结构。采用主模TEIO模式激励,端口处采用推导出的Robin—type边界条件,通过扫频方式求得系统谐振频率,利用等效电路法导出的公式计算出系统的外Q值。数值结果表明,利用边界元法计算波导加载腔这样的半开放系统,具有实现简单,计算精确度高数据输入少,计算时间短等优点。     

一种适合于同轴放电气体激光器的多程环形腔

本文提出了一种适用于同轴放电气体激光器的环形腔方案,给出了这种腔的设计和光束特性。     

Single-Cavity triangular substrate integrated waveguide bandpass filter with complementary triangular split ring resonator

A novel single-cavity equilateral triangular substrate integrated waveguide (TSIW) bandpass filter (BPF) with a complementary triangular split ring resonator (CTSRR) is designed in this paper. A metallic via-hole is used to split the degenerate modes and adjust the transmission zeros (TZs) properly. Meanwhile, the CTSRR is utilized as a resonator to work together with the degenerate modes of the TSIW cavity. The resonant frequency of the CTSRR can be adjusted by its own size. Meanwhile, a TZ is observed in the lower band due to the CTSRR. Finally, a 16% 3dB fractional bandwidth (FBW) triple-mode TSIW BPF with three TZs in both lower and upper bands is simulated, fabricated, and measured. There is a good agreement between the simulated and measured ones.     

新型的可调谐微环谐振器的设计

为了改进微机电系统中的传感器应用范围和特性参数,采用微纳光纤制作了环形谐振腔结构,设计的结构具有尺寸小、损耗低,品质因素高等优点。理论上分析了微纳光纤的光传输模式特性,通过电场的传数矩阵推导了谐振腔中的速度变化与光强变化间的关系,得到了加速度作用下微环谐振腔的谐振波长、周长、有效折射率的变化值间的函数关系。仿真结果分析表明:设计的微环波导电场波动明显,耦合效率较好;光谱强度和3 dB带宽变化较小,Q值达到104;在质量块每增加10 g时,输出光谱图约向右漂移3 nm;加速度与谐振波长漂移量基本呈线性关系,可以通过谐振波长的漂移量来实现对加速度的测量。研究结果能够为全光网络和微机电系统提供实现多种功能的光波导器件。     

一种新型的微波介质谐振器高次倍频器

将微波介质谐振器应用于阶跃管高次倍频器中,这是一种新的尝试.由此构成的微波高次倍频器,既具有微波集成高次倍频器体积小、重量轻、加工简单的特点,又具有微波同轴腔高次倍频器对相邻谐波抑制度高的优点.因而是一种在星、弹航天设备中非常有用的微波固态源部件.已研制成的C波段22次倍频器,集成在两块20×60×1mm的氧化铝陶瓷基片上,对相邻谐波的抑制,在-40℃～+70℃温度范围内优于-50dB.     

A novel cavity resonator measurement method for leaky waveguides

The authors present a method for measuring the phase and leakage constants of leaky waveguides in which power is sent in transversely, in a reversal of the leakage process itself. The cavity therefore requires no coupling holes, and the method is accurate and convenient to use, as shown in an illustrative example