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本文利用琼斯矩阵对偏振模散(PMD),偏振相关损耗(PDL)以及偏振相关增益(PDG)在光纤通信系统中的联合作用下差分群时延的性质进行了研究。提出了PDL和PDG对系统影响的等效性,研究了PDL和PMD级联的模型,比较了PDL和PDG对系统影响的大小,并用数值模拟验证了理论的正确性。 相似文献
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本文用Jones矩阵法对光通信系统中偏振模色散(PMD)和偏振相关损耗(PDL)的共同作用进行了分析,用数值模拟分析了它们共同作用对差分群时延的影响。介绍了PDL补偿系统。 相似文献
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偏振相关损耗对偏振复用系统信道正交性的影响 总被引:3,自引:0,他引:3
在偏振复用系统中,利用两个正交的偏振光作为不同的信道在同一根光纤传输,从而达到使传输信息量加倍的目的.在信号接收端,需要将这两个信道重新分离,分离时除了偏振模式色散(PMD)之外,还会受到偏振相关损耗(PDL)的影响.根据PDL的原理,推导了偏振复用系统中两正交信道夹角与PDL的数值关系,计算了PDL大小对系统的影响.并依据理论模型构建了实验系统,对光纤一个主轴光强进行衰减,描绘出信道间串扰和PDL之间的实验曲线,验证了理论分析的有效性.实验表明,PDL调至最小的时候.若要求串扰控制在-10 dB以内,差分群时延(DGD)应该压制在10 ps以内;当DGD增大到140 ps以后,被标记和没被标记的信道信号强度达到了1:1,系统则完全无法工作,在接收端无法分离信道.本项研究对于保证偏振复用系统的稳定性具有一定的指导意义. 相似文献
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分析了AWG器件的基本原理,并介绍了近年来人们在研制小尺寸AWG、增加器件信道数量,改善器件的损耗、串扰、偏振敏感性和温度相关性等性能,以及AWG与其他器件集成等方面的最新研究进展。 相似文献
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设计、仿真并制备了一种用于光纤布拉格光栅(FBG)解调的阵列波导光栅(AWG)芯片。该芯片基于SOI衬底进行制备,并在AWG的输入/输出波导、阵列波导与平板波导之间采用双刻蚀结构进行优化。经仿真,该AWG的插入损耗为1.5dB,串扰小于 -20dB,3dB带宽为1.5nm。优化后的AWG芯片采用深紫外光刻技术、电感耦合等离子体等技术制备。经测试,该AWG的插入损耗为3dB,串扰小于 -20dB,3dB带宽为2.3nm。搭建了基于该AWG的解调系统,解调实验结果表明,该系统在0.8nm范围内的解调精度可达11.26pm,波长分辨率为6pm。 相似文献
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Kamei S. Kaneko A. Ishii M. Shibata T. Inoue Y. Hibino Y. 《Lightwave Technology, Journal of》2005,23(5):1929-1938
This paper proposes a cascade-connected arrayed-waveguide grating (AWG) as a solution to the problem of crosstalk accumulation in a large-scale AWG multiplexer/demultiplexer (MUX/DEMUX) and demonstrates a 64-channel cascaded AWG module with a very low background crosstalk of less than -80 dB and a total crosstalk of about -34 dB. In this paper, the authors densely integrate 64 additional compactly designed crosstalk-suppressing AWGs whose bandwidths were carefully optimized and directly attach them to a conventional 64-channel AWG. Consequently, in addition to a very low crosstalk, a low insertion loss and a compact size without passband shape distortion are achieved with this module. Based on the performance of the cascaded AWG module, it is then estimated that it is possible to realize a 1000-channel AWG MUX/DEMUX that is free from the problem of crosstalk accumulation. 相似文献
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Demultiplexing using an arrayed-waveguide grating for frequency-interleaved DWDM millimeter-wave radio-on-fiber systems 总被引:1,自引:0,他引:1
The frequency-interleaved dense- wavelength-division-multiplexing (DWDM) millimeter-wave (mm-wave) radio-on-fiber is an indispensable technique to improve the optical spectrum efficiency. We propose possible configurations of multiplexing and demultiplexing (DEMUX) schemes using an arrayed-waveguide grating (AWG) with two input and N output waveguides (N: total channel number). In this paper, we focus on the DEMUX scheme and experimentally demonstrate the DEMUX scheme using a commercially available AWG. In the experiment, 25-GHz-separated two-channel optical double sideband signals modulated by a 60-GHz millimeter-wave carrying a 156-Mb/s data are optically multiplexed by the frequency interleaving. The power penalty after DEMUX, which was due to interchannel interference, was less than 0.5 dB. We also made a transmission experiment over 25-km standard single-mode fiber (SMF). No noticeable power penalty in the received data due to chromatic dispersion of the transmission fiber was observed. This is because only the carrier and a sideband are detected in the proposed DEMUX scheme. 相似文献
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Higashisaka N. Shimada M. Ohta A. Hosogi K. Tobita Y. Mitsui Y. 《Solid-State Circuits, IEEE Journal of》1994,29(7):808-814
GaAs 2.5 Gbps 16 bit MUX/DEMUX LSI's have been successfully developed. DCFL is employed as a basic gate in order to reduce the power dissipation. To avoid the speed degradation caused by using DCFL, various technologies such as 8×2(MUX)/2×8(DEMUX) data conversion processes, a Selector Merged Shift Register, clock overlapping, and a 0.7-μm BPLDD MESFET, have been introduced. Moreover the ECL I/O level interface and single power supply features make it easy to use MUX/DEMUX in optical communication systems. The maximum operating data rate is 3.2 Gbps for both LSI's, and the power dissipation of chips which operates with 2.5 Gbps are as low as 1.3 W for each MUX/DEMUX 相似文献
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Tsalamanis I. Rochat E. Parker M.C. Walker S.D. 《Quantum Electronics, IEEE Journal of》2005,41(7):945-950
We analyze the effect of arrayed-waveguide grating (AWG) polarization dependent loss (PDL) on the orthogonality between polarization multiplexed channels in a cascaded AWG-based access network topology. For a single AWG, with 0.5-dB PDL, we find an experimental degradation in polarization multiplexing orthogonality to be a maximum of 0.9/spl deg/, in good agreement with theory. In addition, experimental, and numerically simulated maps of orthogonality degradation versus input states of polarization (SOP) are investigated and found to agree well. Consequently, we analyze the effect of cascaded AWGs and again find that the experimental result of maximum 2.9/spl deg/ degradation in polarization multiplexing orthogonality closely matches theoretical predictions. Thermal variations are also found to have similar effects for all SOPs, with a measured degradation in orthogonality of up to 2.5/spl deg/ for a temperature range between 20/spl deg/C and 55/spl deg/C. Overall, this indicates the robustness of polarization multiplexing, making it applicable for appropriate deployment in bandwidth/user-enhanced access networks based on cascaded AWGs. 相似文献
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Aberration theory of arrayed waveguide grating 总被引:4,自引:0,他引:4
The general aberration theory of arrayed waveguide grating (AWG) is proposed in this paper. The derived conclusions can be applied to any symmetrical AWGs. With the aberration theory, the spectral response can be optimized. Some performances of an AWG, for example, crosstalk and channel number, are expected to be improved by reducing the aberrations. A common AWG with the Rowland geometry has low aberrations for the absence of the second-order aberration. To further reduce the aberrations, nonstandard AWGs are considered. The AWG based on three stigmatic points is proved to have a perfect performance 相似文献
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We designed a front-end circuit for an analog-to-digital (A/D) converter based on single flux quantum circuitry and tested its functionality at a frequency of up to 43 GHz. The front-end circuit consisted of a pulse generator, a sigma-delta modulator, a 1-to-8 demultiplexer (DEMUX), and superconducting quantum interference device (SQUID) amplifiers. There were 2518 Josephson junctions in the front-end circuit. To operate the circuit at high speed, we designed robust timing against variations in circuit parameters. By using circuit simulations based on the Monte Carlo method, we estimated spread in time lag between clock and data pulses. From this estimate, the timing was optimized to operate the circuit at 40 GHz. The demonstration of the front-end circuit was carried out using the on-chip testing method. Output data were acquired from the modulator through DEMUX. We confirmed proper sigma-delta modulation by analyzing the dependence of the density "1" in the output data on input current level. The proper operation was confirmed in a range of 37-43 GHz. Furthermore, the amplification by the SQUID amplifier was also confirmed at low speed. These results indicate the complete operation of the front-end circuit for superconductive A/D converter. 相似文献
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This paper presents the first unified wavelength division multiplexing (WDM) transmission model for systems incorporating cascaded optical amplifiers and a realistic demultiplexing (DEMUX) characteristic with periodic transfer function. The bit error ratio (BER) is evaluated accounting in rigorous form for the influence of non-Gaussian detected amplified spontaneous emission (ASE) noise, noise correlation between stochastic noise samples in the receiver, the bandwidth of the electrical receiver noise filter, the gain tilt and effective noise figure of optical amplifiers (with as well as without optical ASE noise filtering), channel crosstalk, signal extinction ratio and a one-or two-stage DEMUX implementation. The model is compared to the Gaussian receiver model in realistic design cases providing important information as to the validity of the Gaussian model. Practical design results indicate the link budget dependence on the DEMUX design and the ASE noise filtering 相似文献
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Zhen Sheng Daoxin Dai Sailing He 《Lightwave Technology, Journal of》2007,25(10):3001-3007
Dual-tapered auxiliary waveguides at the exit of the waveguide array are introduced to improve the channel uniformity of an Si-nanowire-based arrayed waveguide grating (AWG) demultiplexer. By using a hybrid simulation method, the dual-tapered auxiliary waveguides of the AWG demultiplexer are optimized reliably and efficiently. A 12-channel AWG demultiplexer is designed as an example, and a small nonuniformity (< 0.5 dB) is achieved. 相似文献
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1 IntroductionTheArrayedWaveguideGrating(AWG)multi plexerisanimportantopticaldeviceforWavelengthDivisionMultiplexing (WDM )inopticaltelecom municationsystems[1~ 5] .Thisdevicecanoffersomebasicfunctionsincludingmultiplexing/demultiplex ing ,add/dropmultiplexingandN×Ninterconnec tion.Also,itpossessessomeadvantages,suchasnarrowerwavelengthspacing ,moresignalchannels,lowercrosstalkandsmootherpassbands.AWGmul tiplexers[6~1 0 ] havebeenfabricatedusingsilicas,InPandpolymers.Amongthem ,apo… 相似文献
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Ishii K. Nosaka H. Ida M. Kurishima K. Yamahata S. Enoki T. Shibata T. Sano E. 《Microwave Theory and Techniques》2003,51(11):2181-2187
We have designed and fabricated a low-power 4:1 multiplexer (MUX), 1:4 demultiplexer (DEMUX) and full-clock-rate 1:4 DEMUX with a clock and data recovery (CDR) circuit using undoped-emitter InP-InGaAs HBTs. Our HBTs exhibit an f/sub T/ of approximately 150 GHz and an f/sub max/ of approximately 200 GHz at a collector current density of 50 kA/spl mu/m/sup 2/. In the circuit design, we utilize emitter-coupled logic and current-mode logic series gate flip-flops and optimized the collector current density of each transistor to achieve low-power operation at required high bit rates. Error-free operation at bit rates of up to 50 Gbit/s were confirmed for the 4:1 MUX and 1:4 DEMUX, which dissipates 2.3 and 2.5 W, respectively. In addition, the full-clock-rate 1:4 DEMUX with the CDR achieved 40-Gbit/s error-free operation. 相似文献