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91.
将两路时钟信号作为泵浦光,与连续探测光一同耦合进高非线性光纤中,四波混频产生的两路闲频光作为整形后的时钟信号,并通过控制两路时钟信号之间的相对时间延迟来减小光纤四波混频干扰。研究了整形前时钟信号占空比的变化与整形后时钟质量的关系以及最佳占空比下输入时钟信号和输出时钟信号的相对幅度抖动的关系,发现在占空比由小到大变化的过程中,整形后时钟信号的质量总体上先变好后变坏;在最佳占空比0.14下,两路时钟信号的相对幅度抖动由原来的13.934 9%和13.958 6%下降到2.03%和2.12%,表明了该方案的可行性。 相似文献
92.
Quan Pan Xiongshi Luo Zhenghao Li Zhengzhe Jia Fuzhan Chen Xuewei Ding C. Patrick Yue 《半导体学报》2022,43(7):072401-1-072401-10
This paper presents a 26-Gb/s CMOS optical receiver that is fabricated in 65-nm technology. It consists of a triple-inductive transimpedance amplifier (TIA), direct current (DC) offset cancellation circuits, 3-stage gm-TIA variable-gain amplifiers (VGA), and a reference-less clock and data recovery (CDR) circuit with built-in equalization technique. The TIA/VGA front-end measurement results demonstrate 72-dBΩ transimpedance gain, 20.4-GHz −3-dB bandwidth, and 12-dB DC gain tuning range. The measurements of the VGA’s resistive networks also demonstrate its efficient capability of overcoming the voltage and temperature variations. The CDR adopts a full-rate topology with 12-dB imbedded equalization tuning range. Optical measurements of this chipset achieve a 10−12 BER at 26 Gb/s for a 215−1 PRBS input with a −7.3-dBm input sensitivity. The measurement results with a 10-dB @ 13 GHz attenuator also demonstrate the effectiveness of the gain tuning capability and the built-in equalization. The entire system consumes 140 mW from a 1/1.2-V supply. 相似文献
93.
沙建新 《微电子学与计算机》1993,10(11):36-37
利用TurboC具有特色的中断函数,构造出一个编程简单,使用方使的定时中断服务程序,为推广C语言在测控系统等领域的运用打下了基础。 相似文献
94.
95.
In the space of diffeomorphisms of an arbitrary closed manifold of dimension ≥ 3, we construct an open set such that each difteomorphism in this set has an invariant ergodic measure with respect to which one of its Lyapunov exponents is zero. These difteomorphisins are constructed to have a partially hyperbolic invariant set on which the dynamics is conjugate to a soft skew product with the circle as the fiber. It is the central Lyapunov exponent that proves to be zero in this case, and the construction is based on an analysis of properties of the corresponding skew products. 相似文献
96.
97.
Jiying Xiang Zhen Wu Ping Zhang Dexiu Huang Gaoshang Wei 《Optics & Laser Technology》1998,30(2):109-112
A disadvantage of using a galvanometer as the horizontal scanner in CSOM and OCT is its nonlinear distortion caused by the rotational inertial. This is inevitable even if a closed loop is equipped. Here, a second closed loop is introduced to provide pixel clocks to reduce the pincushion distortion of the images. A subdivided step motor is employed to be the vertical scanner as the result of price consideration. Nonetheless, the conventional linearity model of the peck torque with a winding current relationship is no longer in agreement with the experiment when the winding current is low, while a parabolic model is more likely to be reasonable. Relational treatment is proposed in the paper. Both methods have proved to be good enough to meet the requirement of a super resolution scanning imaging. 相似文献
98.
A multi-function device based on two terahertz optical asymmetric demultiplexers (TOAD) is proposed,which can be used simultaneously as demultiplexing,data regeneration,clock recovery and wavelength conversion unit. The device can work at an ultra-high speed optical time-division multiplexing (OTDM) system with relatively low speed components. 相似文献
99.
Alan L. Macdonald 《Foundations of Physics Letters》1992,5(5):493-494
There is no indication of time dilation of clocks or of length contraction of rods in Marzke and Wheeler's clock or in Desloge's metrosphere. 相似文献
100.
本文介绍一个多相同步时序数字电路的时序模型及时序冲突的检验算法。该方法能检查出时序冲突类型,冲突的具体位置及时钟系统设置的合理性。该算法已在Sum-4/SPARC上实现,能快速准确检查出非覆盖多相时钟同时时序电路存在的时序冲突,冲突覆盖率高。 相似文献