共查询到19条相似文献,搜索用时 125 毫秒
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有源光纤环形腔的频率滤波特性 总被引:1,自引:0,他引:1
本文首先从理论上通过简单的分析得以了有源光纤环形腔的输出谱密度函数公式,该式清楚地表明光纤环形腔的频率滤波特性。从该公式出发,详细分析了环形腔输入光纤宽和环形腔参数对输出光谱谱型和线宽的影响。最后,通过设计不同的环形腔的自由谱宽和不同线宽的激光器作为输出光源,对上述理论分析做了实验验证。理论和实验表明,由于环形腔的强度传递函数是多峰的响应函数,环形腔自由谱宽和输入激光线宽的大小直接影响到环形腔输出光频谱形状,即是单峰输出还是多峰输出,对于不同形状的光谱输出,输出激光的线宽受环形腔的参数影响也各不相同。 相似文献
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提出一种利用电流传送器设计的三输入单输出电压模式双二阶有源滤波器。通过选择不同的输入信号,在输出端得到二阶低通、高通、带通、带阻和全通五种滤波功能。该滤波器具有低的参数灵敏度和高输入、输出阻抗。模拟仿真结果表明所提方案是可行的。 相似文献
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在PLL频率合成器中,环路滤波器的设计对PLL的输出性能有着非常重要的影响。然而在某些场合VCO要求的调谐电压比PLL的充电泵输出电压高得多,这种情况下就必须选用有源环路滤波器。有源环路滤波器基本上可以分为差分结构和单端结构2种,可根据实际应用的PLL充电泵输出来进行选择。在进行有源环路滤波器的设计过程中,选择合理的环路滤波器拓扑结构以及低噪声放大器将最小化对PLL相位噪声的影响。 相似文献
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混合有源电力滤波器分析及应用探讨 总被引:1,自引:0,他引:1
有源电力滤波器由于有很好的滤波特性:动态特性好、体积小等优势一直得到广泛关注,但其缺点又限制了其实际应用。将有源电力滤波器与无源电力滤波器相结合,构成混合有源滤波器(AF),取两者之长补有源电力滤波器(APF)之短,可以降低谐波补偿系统的成本,达到APF实用的目的。本文对几种主要的混合APF(HA PF)作了分析和比较。 相似文献
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用Tow-Thomas电路设计含有限非零传输零点有源滤波器的方法 总被引:4,自引:1,他引:3
Tow-Thomas电路是一种实现全极点滤波器的典型电路。本文给出了用Tow-Thoms电路设计含有限非零传输零点有源滤波器的方法,从而使Tow-Thomas电路可用于单片集成滤波器电路。而文中给出的公式可用于计算外接元件。设计实例表明了文中给出的计算公式的正确性。 相似文献
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本文研究了一种直接利用晶体管或场效应管来模拟高Q值电感,并利用此电感来制作L波段和S波段窄带有源滤波器的方法。利用此方法制作了两个高性能的窄带有源带通滤波器:一个中心频率为2.3GHz,其带宽为90MHz左右,带内插入损耗为0dB;一个中心频率在1.5GHz左右,并且中心频率可调,其带宽为80MHz左右,带内有10dB的增益 相似文献
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A band-pass microwave photonic filter(MPF)based on Lyot-Sagnac filter and two cascaded optical structures is demonstrated.In the experiment,a stabilized and tunable multi-wavelength optical source is obtained by slicing the broadband optical source(BOS)with a Lyot-Sagnac filter.A standard single-mode fiber(SMF)and a fiber ring resonator are cascaded to improve the mainlobe-to-sidelobe suppression ratio(MSSR)and Q-factor of the filter.The analysis shows that MSSR and Q-factor are improved by reducing the split ratio of the coupler or increasing the length of fiber in fiber ring resonator.The results have significant guidance for MPF design by choosing appropriate devices and parameters.Based on the analyses,a band-pass filter with MSSR of 53.54 dB and Q-factor of 4048 is achieved by choosing the split ratio of0.01,the length of SMF of 30 km and the length of fiber in fiber ring resonator of 152.27 cm. 相似文献
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We propose a simple technique to stabilize the optical output intensity of a fiber ring resonator. The electronic feedback circuit system, which consists of two voltage control oscillators, a phase comparator, and a low pass filter, is applied to the fiber ring resonator in order to compensate the optical phase shift in the ring loop. The reference electrical signal determines the operating condition of the fiber ring resonator for the desired optical output signal. The experimental results within the operating range agree well with the analytical results. The simulated performance of the proposed model is also compared with that of other existing models and shows significant improvement over them. 相似文献
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谐振式光纤陀螺中环形谐振腔的实验研究 总被引:3,自引:0,他引:3
文中报道了谐振式光纤陀螺中光纤谐振腔的研究工作,首先简述了谐振式光纤陀螺的基本原理,然后对光纤环形腔的谐振性进行了分析,给出谐振条件,并且根据系统的性能要求,对陀螺的谐振腔光路系统进行了设计。 相似文献
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A finesse-enhanced Er-doped-fiber ring resonator 总被引:2,自引:0,他引:2
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 相似文献
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We consider an optical filter constructed from a simple ring resonator with two electro-optical directional couplers and a fiber amplifier in the ring. By adjusting the coupling coefficient of the electro-optical directional couplers, the finesse of this optical filter can be controlled over a specified range. The variation in the insertion loss of the optical filter can be overcome by adjusting the gain of the fiber amplifier simultaneously. This paper analyzes theoretically the performance of the optical filter, as a function of the coupling coefficient of the electro-optical directional coupler and the gain of the fiber amplifier. We also show that it is possible to design an optical filter of wide adjustable finesse by changing only the coupling coefficient of the electro-optical directional couplers, leaving the gain of the fiber amplifier unchanged. This simpler method results only in a slight change in the insertion loss if an appropriate condition is chosen. The filter will be useful in coherent optical systems, where the bandwidth of the optical filter needs to be appropriately adjusted under varying biasing and signaling conditions, or as an optical discriminator with an adjustable Q-factor 相似文献
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提出并验证了一种借助于光纤环的选频特性实现辅助滤波的光电振荡器,利用偏振分束器(PBS)和偏振合束器(PBC)构成的双环路结构抑制掉部分光电振荡器的边模,同时借助于光纤环的光学梳状频率特性,对振荡器环路中的光信号模式再次进行选择,既起到边模抑制的作用,又提高了光电振荡器谐振腔的Q值.仿真结果表明:采用光纤环辅助滤波有利于光电振荡器的边摸抑制和单模输出,在保证光电振荡器输出低相位噪声和高频谱纯度微波信号的情况下,边模抑制比超过160 dB,模式间隔达到370 MHz,降低了对电域带通滤波器的性能要求,是一种新的光电振荡器设计方案. 相似文献
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基于腔衰荡光谱技术的三参量同时测量光纤微腔传感器 总被引:1,自引:1,他引:0
提出并实现了一种基于腔衰荡光谱(CRDS)技术的三参量同时测量的光纤微腔传感器。利用高频CO2激光脉冲技术在1 060nm单模光纤(SMF)上直接刻蚀光学微腔,并将其作为传感单元接入到光纤环谐振腔中,通过测量脉冲激光衰荡时间实现了对温度、折射率和应变3个不同参数的同时传感测量。整个传感器系统采用光时分复用(OTDM)技术,3个带有光纤微腔传感单元的光纤衰荡腔并联连接,共用一个光源和探测器,在3路光纤环中引入不同的相位调制项,使其输出的衰荡信号在时域上有效的分开,从而达到三参量传感的目的。传感器结构合理,可操作性强,后期数据处理工作简单易行,实验结果重复性良好。在此基础之上,可以将此传感器结构推广到四参量,甚至更多参量的传感器系统中。 相似文献