共查询到18条相似文献,搜索用时 171 毫秒
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两段级联宽带碲基掺铒光纤放大器特性研究 总被引:2,自引:2,他引:0
利用四能级结构速率方程组和光功率传输方程组,研究了在碲基掺铒光纤(EDTF)中内插一个光隔离器、形成两段级联的碲基掺铒光纤放大器(EDTFA)后对EDTFA性能的改善.结果表明,在给定泵浦方式、泵浦功率、纤芯掺杂浓度和输入信号功率条件下,两段级联EDTFA可以有效的抑制光纤中反向传输放大自发辐射(ASE)噪声,降低反转粒子数的消耗,从而提高信号增益、输出功率,并且降低了噪声系数.对不同光纤长度和光隔离器内插在光纤中不同位置的研究表明,当光纤为最佳长度和光隔离器在最佳位置处时,可使短波长信号增益增加10 dB,噪声系数减小1 dB,并进一步增加了放大带宽以及功率转换效率. 相似文献
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本文对低泵浦功率下1480nm泵浦的掺铒光纤放大器的特性进行了数值分析,分别给出了正,反向泵浦下大信号(1mW)输入时掺铒光纤放大器的增益-泵浦功率和噪声指数-泵浦功率曲线,说明了低泵浦功率对掺铒功率对掺期铒光纤放大器特性的影响。 相似文献
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时书丽 《光纤与电缆及其应用技术》2003,(5):8-9,35
阐述了掺铒光纤放大器的放大原理,给出了计算放大器增益和自发辐射噪声的公式,并且给出了增益和噪声与掺铒光纤长度、泵浦功率、输入信号功率之间的关系。 相似文献
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为了研究不同增益光纤长度下1555nm高功率光纤放大器的输出功率,采用两级混合结构的方法,用掺铒光纤放大器和双包层铒镱共掺光纤放大器分别作为1级预放大器和2级主放大器。掺铒光纤放大器对信号光进行预放大,并提高放大器的信噪比;双包层铒镱共掺光纤放大器为主放大器,其双包层结构可以把更多的多模抽运光耦合进系统。对铒镱共掺光纤的最佳长度做了理论分析和实验验证,在信号光功率为10mW、掺铒光纤放大器的抽运功率为318.58mW、双包层铒镱共掺光纤放大器的抽运功率为11.71W、增益光纤长度为14m时,输出功率取得了2.11W的实验数据。在分析输出信号光谱时发现,L波段附近有放大自发辐射谱出现,这是选择的增益光纤过长导致的。结果表明,在光功率和信号光功率一定时,光纤放大器有一个最佳的光纤长度。这一结果对研究光纤放大器的高功率输出是有帮助的。 相似文献
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A. R. Gasanov K. F. Abduragimov M. A. Gurbanov 《Radioelectronics and Communications Systems》2008,51(5):284-288
It is researched an influence of cross section size of incident to lightsensitive photoreceiver surface radiation on pulse shape in acousto-optic delay line with direct detection. Corresponding transient characteristic was obtained, it was used for output response analysis to input pulse signal with different duration. 相似文献
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Mori A. Sakamoto T. Kobayashi K. Shikano K. Oikawa K. Hoshino K. Kanamori T. Ohishi Y. Shimizu M. 《Lightwave Technology, Journal of》2002,20(5):822-827
This paper describes the development of a 1.58-/spl mu/m broad-band and gain-flattened erbium-doped tellurite fiber amplifier (EDTFA). First, we compare the spectroscopic properties of various glasses including the stimulated emission cross sections of the Er/sup 3+4/ I/sub 13/2/ /sup 4/I/sub 15/2/ transition and the signal excited-state absorption (ESA) cross sections of the Er/sup 3+4/ I/sub 13/2/ - /sup 4/I/sub 9/2/ transition. We detail the amplification characteristics of a 1.58-/spl mu/m-band EDTFA designed for wavelength-division-multiplexing applications by comparing it with a 1.58-/spl mu/m-band erbium-doped silica fiber amplifier. Furthermore, we describe the 1.58-/spl mu/m-band gain-flattened EDTFA we developed using a fiber-Bragg-grating-type gain equalizer. We achieved a gain of 25.3 dB and a noise figure of less than 6 dB with a slight gain excursion of 0.6 dB over a wide wavelength range of 1561-1611 nm. The total output power of the EDTFA module was 20.4 dBm and its power conversion efficiency reached 32.8%. 相似文献
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Sang-Woong Yoon 《Microwave Theory and Techniques》2007,55(4):643-647
This paper presents error vector magnitude (EVM) behavior under two different modes of a reference voltage (Vref); one is a static EVM with a constant Vref and the other is a dynamic EVM with a pulsed Vref. A 2.4-GHz two-stage power amplifier (PA) is implemented by GaAs HBT technology to investigate EVM behavior for IEEE 802.11 g wireless local area network application. A square wave pulse with the duty cycle of 50% is applied as Vref for dynamic operation mode. In this paper, it is shown that a dynamic EVM is worse than a static EVM because a transient response of PA output distorts preamble and signal in orthogonal frequency division multiplexing signal bursts. This transient response is explained by a two-pole thermal network in this study, and transient response experiments with a resistor-capacitor (R-C) network at a power supply were performed for verification 相似文献
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Mori A. Sakamoto T. Shikano K. Kobayashi K. Hoshino K. Shimizu M. 《Electronics letters》2000,36(7):621-622
A gain-flattened Er3+-doped tellurite fibre amplifier (EDTFA) with an expanded L-band is presented. The amplifier has an average gain of 28 dB and a noise figure of <6 dB with a slight gain excursion of 1 dB over a wide wavelength range of 1581-1616 nm. The total output power of the EDTFA module was 20.5 dBm and its power conversion efficiency reached 25% 相似文献
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实验研究了不同脉冲能量的飞秒激光诱发硅PIN光电二极管瞬态响应信号的特性。发现了探测器响应瞬态响应信号相继出现了三个明显的相位,深入讨论了飞秒激光诱发的高注入载流子在瞬态响应信号演化过程中所起的作用。结果表明,高注入载流子产生的空间电荷屏蔽效应是导致瞬态响应信号呈现三个相位的主要因素,它导致瞬态响应信号的持续时间主要取决于载流子双极扩散的速度。增加飞秒激光的脉冲能量会进一步延长探测器瞬态响应信号的持续时间。因此,飞秒激光会削弱探测器的工作性能,尤其是在高速信号探测中的工作性能。 相似文献
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A large-signal model for a four-level laser system which includes time variation effects has been used to study low frequency response characteristics, two-channel crosstalk and transient effects in praseodymium-doped fluoride fiber amplifiers (PDFFA). Pump power modulation results in a low-pass transfer of modulation to signals amplified in the PDFFA. Low-frequency compression of the PDFFA input/output signal transfer characteristic has been observed. Due to a relatively long lifetime of the 1G4 metastable level, multichannel crosstalk lower than 30 dB has been calculated for modulation frequencies higher than 600 kHz. Response of the PDFFA toward a low-frequency signal square pulse exhibits a characteristic overshoot that originates from the PDFFA saturation by the amplified signal 相似文献
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The experimentally significant, long time transient response of a lossless anisotropic plasma to a short electromagnetic pulse is given. Natural oscillations asymptotically approach the plasma cutoff and resonance frequencies. In addition, complicated transient polarization effects are present in the response signal. 相似文献
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双包层Er^3+/Yb^3+共掺光纤放大器是一种新型光纤放大器,这里基于速率方程的“离散”算法,实现了脉冲泵浦方式下该型放大器动态特性的分析。研究了脉冲泵浦方式下,输入信号的动态响应。结果表明:当脉冲持续时间等于1.5ms时,输入信号的放大会终止,到下一脉冲来临时,信号放大又快速地上升到最大值;当脉冲持续时间为0.15ms时,输入信号的放大不会终止,但随着脉冲持续时间的增大,信号输出功率会越来越小。 相似文献