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排序方式: 共有185条查询结果,搜索用时 31 毫秒
91.
92.
基于SOA光纤环镜的NRZ信号时钟分量提取的数值模拟 总被引:7,自引:7,他引:0
采用半导体光放大器(Semiconductor Optical Amplifier, SOA)的分段模型,对基于SOA光纤环镜的非归零 (Non-Return-to-Zero, NRZ)信号时钟分量提取进行了数值模拟.SOA光纤环镜可以将NRZ信号转化为包含其时钟分量的伪归零(Pseudo-Return-to-Zero, PRZ)信号给出了2.5Gb/s下的模拟计算结果,并与实验结果进行了比较,进一步给出了10Gb/s下的模拟计算结果. 相似文献
93.
94.
Measurement of the carrier recovery time in SOA based on four-wave mixing on narrow-band ASE spectrum
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Carrier recovery time is a key parameter that determines the performance of a semiconductor optical amplifier (SOA). A measurement method of carrier recovery time in SOA based on a nearly degenerate four-wave mixing of narrow-band amplified spontaneous emission (ASE) spectra is presented. The results show the carrier times are 50.2, 44.6, and 23.6 ps when the injected currents are 120, 180, and 240 mA, respectively, which are in agreement with the nominal values of the sample. 相似文献
95.
We propose and demonstrate all-optical clock recovery (OR) from nonreturn-to-zero differential phase-shift- keying (NRZ-DPSK) signals at different bit rates theoretically and experimentally. By pre-processing with a single optical filter, clock component can be enhanced significantly and thus clock signal can be extracted from the preprocessed signals, by cascading a OR unit with a semiconductor optical amplifier based fibre ring laser. Compared with the previous preprocessing schemes, the single filter is simple and suitable for different bit rates. The clock signals can be achieved with extinction ratio over lOdB and rms timing jitter of 0.86 and 0.9 at 10 and 20 Gb/s, respectively. The output performances related to the bandwidth and the detuning of the filter are analysed. By simply using a filter with larger bandwidth, much higher operation can be achieved easily. 相似文献
96.
In this paper, the self-startlng mode-locking characteristics of all-fiber lasers are in-vestigated theoretically. The mechanism of self-starting mode-locking is analyzed and the experimental phenomena are explained successfully by introducing effective energy gain. The modulation characteristics of all-fiber lasers and the effect of gain saturation on modulation characteristics are discussed by analyzing the transmissivity of Er-doped fiber loop. Finally, the dynamic processes of all-fiber self-starting mode-locked lasers are simulated numerically. 相似文献
97.
对与InP晶格匹配的InGaAsP四元系量子阱材料进行了热稳定性能的研究,通过光荧光谱(PL)的测量发现:量子阱材料在650 ℃以上的常规退火条件下,有最大可达155 m eV 的PL峰值蓝移,表明禁带宽度有明显增大.运用1.064 μm 连续输出的Nd:YAG激光器进行光子吸收诱导无序(PAID)技术的研究,比较量子阱材料被辐照前后荧光谱的峰值位置和谱宽,发现量子阱结构的禁带宽度在激光辐照后有明显增大,证明有量子阱混合现象产生.衬底预加热结果表明,提高衬底温度可减少PAID中的激光辐照时间和平均功率密度. 相似文献
98.
All-optical error-bit amplitude monitor based on NOT and AND gates in cascaded semiconductor optical amplifiers
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This paper proposes and simulates a novel all-optical error-bit amplitude monitor based on cross-gain modulation and four-wave mixing in cascaded semiconductor optical amplifiers (SOAs), which function as logic NOT and logic AND, respectively. The proposed scheme is successfully simulated for 40 Gb/s return-to-zero (RZ) signal with different duty cycles. In the first stage, the SOA is followed by a detuning filter to accelerate the gain recovery as well as improve the extinction ratio. A clock probe signal is used to avoid the edge pulse-pairs in the output waveform. Among these RZ formats, 33% RZ format is preferred to obtain the largest eye opening. The normalized error amplitude, defined as error bit amplitude over the standard mark amplitude, has a dynamic range from 0.1 to 0.65 for all RZ formats. The simulations show small input power dynamic range because of the nonlinear gain variation in the first stage. This scheme is competent for nonreturn-to-zero format at 10Gb/s as well. 相似文献
99.
Dual-Wavelength Erbium-Doped Fibre Ring Laser by Cascading Tunable Bandpass Filter with Bandstop Filter
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A novel fibre ring laser is proposed and successfully demonstrated. By cascading a tunable bandpass filter with a bandstop filter to construct the desired narrow dual-transmission-peak spectrum, and employing a segment of unpumped erbium-doped fibre as a saturable absorber, a stable fibre ring laser is achieved at room temperature. The proposed laser can operate in dual-wavelength with the wavelength spacing of 0.48 nm and the extinction ratio more than 50 dB or switch between the two wavelengths by adjusting a polarization controller. The stability is investigated experimentally and explained theoretically. 相似文献
100.
建立了基于集成双波导半导体光放大器的光开关(ITG-SOA-Switch)的理论分析模型.与半导体光放大器(SOA)的特性相比较表明,由于ITG-SOA-Switch合并了多种物理效应,故其静态增益饱和曲线在饱和功率点附近具有大幅度陡峭下降的独特性质.理论分析和10 Gbit/s波长转换模拟结果显示,恰当地选择输入抽运光的功率范围,ITG-SOA-Switch波长转换器输出转换光的消光比特性较之输入抽运光会有显著的改善.
关键词:
波长转换
半导体光放大器
集成双波导半导体光放大器
光开关 相似文献