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远程抽运光放大技术已广泛应用于超长跨距光传输系统。在介绍超长跨距光传输系统远程抽运光放大技术的设计方案基础上,得出了远程增益单元的增益和噪声指数与远程抽运光放大系统输出光信噪比的关系。从选择掺铒光纤、采用反射镜和设计隔离器位置等三方面对远程增益单元(RGU)的结构设计进行了理论分析和实验研究,比较了不同方案下的远程增益单元的增益与噪声指数,通过优化光路设计,提出了不同抽运功率和信号光功率条件下的最佳远程增益单元光路结构。结果表明,选用低浓度的HE980掺铒光纤、采用高反射率和低插损的反射镜及设计合适的光隔离器位置,远程增益单元的增益和噪声指数能得到明显的改善。 相似文献
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基于石英光纤作为增益介质,采用龙格-库塔法、打靶法求解多波长双向泵浦光纤拉曼放大器的功率耦合波方程,得到拉曼放大器的增益带宽,平均增益,增益平坦度以及泵浦光和信号光沿光纤的分布。再通过粒子群优化算法对同一数量泵浦光不同排列双向系统进行逐个优化分析,在14种双向泵浦结构中选出性能较优的三种结构,再对它们优化参数设置,最终得到性能最优的双向泵浦结构BBFF。研究结果表明:在仅有四个泵浦光的情况下,双向多泵浦结构BBFF具有最优的平均增益和增益平坦度,并且得到了开关增益为23.1665 dB,增益平坦度为0.794 dB的双向泵浦结构。 相似文献
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拉曼光纤放大器的一种简化模型 总被引:2,自引:0,他引:2
提出了一种多泵浦反向光纤拉曼放大器(FRA)的新型实用模型,能够给出小信号增益和噪声指数。采用数值计算泵浦光的传播规律,利用此结果解析求解信号光沿光纤的功率演化,解决了泵浦与信号光反向传输的问题。利用拟合图谱通过插值得到拉曼增益系数代替传统的将拉曼增益谱近似为三角形的方法。模型中考虑了泵浦与泵浦、泵浦与信号之间的相互作用,并包含自发拉曼散射噪声。 相似文献
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本文对基于FBG的L—band EDFA进行了实验研究。通过在光路中加入FBG反射铒纤的后向ASE,980nm和1480nm泵浦的L—band EDFA的泵浦转换效率都有了明显的提高。加入FBG后,在1570~1600nm的30nm波长范围内,980nm泵浦功率为72mW时,平均增益13.7dB,增益起伏在小于±0.25dB;1480nm泵浦功率为39mW时,平均增益17.5dB,增益起伏小于±1.5dB。通过我们的实验证明这一结构的L—band EDFA是简单高效的。 相似文献
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文章提出了一种基于三端口增益平坦滤波器、且在拓扑结构上不同于以往并行或串行结构的掺铒光纤放大器(EDFA)的新结构。理论模拟显示,同常规的并行结构EDFA相比,该新型结构在保证C波段EDFA性能的同时亦可将L波段掺铒光纤(EDF)用量减少48%以上,改善L波段泵浦效率55%以上。实验中,我们在C波段使用两只输出功率分别为106.9和109.6mW的980nm泵浦激光器,两段EDF的长度分别为8.5和9.6m,在L波段我们仅用1只80mW的1480nm泵浦激光器,EDF长度为19.8m。试验结果显示,在C+L波段内得到的信号增益〉23dB,增益平坦度〈0.6dB,噪声指数在C和L波段内分别〈4.4dB和5.6dB。 相似文献
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The amplification characteristics of an Er/sup 3+/-doped tellurite-based fibre amplifier (EDTFA) with 980 nm band pumping are described. The optimum pump wavelength and length of the newly developed EDTF are investigated in order to obtain both a low noise figure and a high gain simultaneously. We realise a low noise figure of less than 4.5 dB with a pump wavelength of 976.5 nm and a 0.4 m EDTF. 相似文献
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K.H. Yla-Jarkko C. Codemard J. Singleton P.W. Turner I. Godfrey S.-U. Alam J. Nilsson J.K. Sahu A.B. Grudinin 《Photonics Technology Letters, IEEE》2003,15(7):909-911
We present results on a low-cost cladding-pumped L-band amplifier based on side pumping (GTWave) fiber technology and pumped by a single 980-nm multimode diode. We show that simultaneous noise reduction and transient suppression can be achieved by using gain clamping by a seed signal (/spl lambda/=1564 nm). In the gain-clamping regime, the amplifier exhibits 30-dB gain over 1570-1605-nm spectral band with noise figure below 7 dB. The noise figure can be further reduced to below 5 dB by utilizing a low power single-mode pump at 980 nm. The erbium-doped fiber amplifier is relatively insensitive to input signal variations with power excursions below 0.15 dB for a 10-dB channel add-drop. 相似文献
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This paper presents the design of a low-power ultra-wideband low noise amplifier in 0.18-mum CMOS technology. The inductive degeneration is applied to the conventional distributed amplifier design to reduce the broadband noise figure under low power operation condition. A common-source amplifier is cascaded to the distributed amplifier to improve the gain at high frequency and extend the bandwidth. Operated at 0.6V, the integrated UWB CMOS LNA consumes 7mW. The measured gain of the LNA is 10dB with the bandwidth from 2.7 to 9.1GHz. The input and output return loss is more than 10dB. The noise figure of the LNA varies from 3.8 to 6.9dB, with the average noise figure of 4.65dB. The low power consumption of this work leads to the excellent figure of gain-bandwidth product (GBP) per milliwatt 相似文献
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Pedersen B. Thompson B.A. Zemon S. Miniscalco W.J. Wei T. 《Photonics Technology Letters, IEEE》1992,4(1):46-49
The authors examine relative merits of exciting Er3+ amplifiers at the three wavelengths for which high-power laser diodes are available at 800, 980, and 1480 nm. Model calculations are confirmed by a detailed experimental comparison of the power requirements for pumping in the 800-nm band and at 980 nm. To obtain comparable performance with respect to gain and noise figure, 7-8 dB more power is required when pumping in the 800-nm-band 相似文献
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High-performance in W -band monolithic pseudomorphic InGaAsHEMT LNA's and design/analysis methodology
Wang H. Dow G.S. Allen B.R. Ton T.-N. Tan K.L. Chang K.W. Chen T.-h. Berenz J. Lin T.S. Liu P.-H. Streit D.C. Bui S.B. Raggio J.J. Chow P.D. 《Microwave Theory and Techniques》1992,40(3):417-428
High-performance W -band monolithic one- and two-stage low noise amplifiers (LNAs) based on pseudomorphic InGaAs-GaAs HEMT devices have been developed. The one-stage amplifier has a measured noise figure of 5.1 dB with an associated gain of 7 dB from 92 to 95 GHz, and the two-stage amplifier has a measured small signal gain of 13.3 dB at 94 GHz and 17 dB at 89 GHz with a noise figure of 5.5 dB from 91 to 95 GHz. An eight-stage LNA built by cascading four of these monolithic two-stage LNA chips demonstrates 49 dB gain and 6.5 dB noise figure at 94 GHz. A rigorous analysis procedure was incorporated in the design, including accurate active device modeling and full-wave EM analysis of passive structures. The first pass success of these LNA chip designs indicates the importance of a rigorous design/analysis methodology in millimeter-wave monolithic IC development 相似文献
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This paper presents millimeter wave monolithic microwave integrated circuit (MMIC) low noise amplifiers using a 0.15 µm commercial pHEMT process. After carefully investigating design considerations for millimeter-wave applications, with emphasis on the active device model and electomagnetic (EM) simulation, we designed two singleended low noise amplifiers, one for Q-band and one for V-band. The Q-band two stage amplifier showed an average noise figure of 2.2 dB with an 18.3 dB average gain at 44 GHz. The V-band two stage amplifier showed an average noise figure of 2.9 dB with a 14.7 dB average gain at 65 GHz. Our design technique and model demonstrates good agreement between measured and predicted results. Compared with the published data, this work also presents state-of-the-art performance in terms of the gain and noise figure. 相似文献
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Erbium-doped fiber amplifiers (EDFAs) with high gain generally degrade the signal-to-noise ratio by at least 3 dB. In the conventional wavelength band, noise figures close to the so-called quantum limit can be obtained by strong pumping. Due to their lower average population in the metastable level, this limit is not reached by amplifiers designed for the long-wavelength band (L-band). In this paper, the lower noise figure limit is determined for such amplifiers. It has been found that the noise figure for typical gain values of about 30 dB can be very close to the quantum limit, whereas significantly larger noise figure values result for small amplifier gains. The lower limit decreases with increasing gain if the gain values are beyond 5 dB. In addition, the results reveal that low temperatures yield better noise figure. 相似文献
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报道了工作频率分别为10.7-11.6GHz和11.7-12.2GHzGaAs单片接收机的研制结果。接收机并包括四种电路,即低噪声效大器、介质稳频振荡器、混频器和中频放大器。电路均采用GaAs全离子注入平面工艺创作,并封装在金属管壳内测试.10.7-11.6GHz接收机的噪声系数达到3.5dB,增益大于35dB;11.7-12.2GHz接收机的噪声系数可达到4dB,增益大于31dB。 相似文献
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宽频带低噪声放大器设计 总被引:1,自引:0,他引:1
采用Lange耦合器的宽频带特性设计L/S波段平衡式低噪声放大器电路,并通过仿真设计软件对放大器的工作频带、噪声系数、增益及输入、输出驻波比等几个重要指标进行优化。最后设计的放大器在1.2~2.5GHz频率范围内增益为33~35dB,噪声系数不大于1dB,输入输出驻波比小于1.5,达到了预定的技术指标要求,性能良好。 相似文献