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91.
Jiun‐Wei Horng Chun‐Li Hou Chun‐Ming Chang Hung‐Pin Chou Chun‐Ta Lin Yao‐Hsin Wen 《ETRI Journal》2006,28(4):486-494
Two current‐mode and/or voltage‐mode quadrature oscillator circuits each using one fully‐differential second‐generation current conveyor (FDCCII), two grounded capacitors, and two (or three) grounded resistors are presented. In the proposed circuits, the current‐mode quadrature signals have the advantage of high‐output impedance. The oscillation conditions and oscillation frequencies are orthogonally (or independently) controllable. The current‐mode and voltage‐mode quadrature signals can be simultaneously obtained from the second proposed circuit. The use of only grounded capacitors and resistors makes the proposed circuits ideal for integrated circuit implementation. Simulation results are also included. 相似文献
92.
93.
利用激光二极管(LD)阵列侧面抽运声光(AO)调Q的Nd:YAG激光器作为抽运源,研究了在不同声光重复频率和输出镜透过率的情况下,内腔式KTA-光参量振荡器(OPO)的输出特性.通过对单谐振光参量振荡器阈值公式的讨论,采用平凹腔的结构以及较短的腔长,降低了光参量振荡器的振荡阈值.当声光重复频率为4 kHz,输出镜透过率为30%,抽运电流为14.5 A时,光参量振荡器的1570 nm激光输出脉冲峰值功率达到5.6×104 W,脉冲宽度为2.5 ns,实验中最大平均输出功率为560.3 mW.结果表明,具有良好热性能的非线性晶体KTA是制造小型、轻便光参量振荡激光器的理想材料. 相似文献
94.
分析了当前微弱信号检测领域中常用的三种检测方法,提出了将混沌技术应用于微弱信号的检测,阐述了基于Duffing混沌振子的微弱信号的检测原理和过程,给出了Matlab的仿真实验结果,理论分析和仿真表明该方法简单、有效、易于实现. 相似文献
95.
通过对稳定的非线性动力系统增加一个动力吸振器进行耦合,再选择合适的参数,使得非混沌系统产生了混沌.同时,利用Mdnikov方法对耦合后的Duffing系统进行理论分析,给出了混沌出现的阀值条件.仿真结果进一步说明了该混沌反控制方法的有效性. 相似文献
96.
介绍了空气清新机(负离子发生器)的组成及原理。以美国生产的空气清新机产品(LIVING AIR DEVICE)为基础,提出自动化程度较高的空气清新机实用电路。介绍各块功能的特点,最后给出实验结果。 相似文献
97.
介绍了由罗柯夫斯基线圈组成的电流互感器的基本原理 ,设计了一种通过VCO实现的V F转换电路。实验结果表明这种V F转换电路具有良好的实用性 相似文献
98.
徐兰珍 《西安邮电学院学报》1996,1(4):37-40
这里主要讨论在能量表象中利用密度矩阵处理线性谐振子问题,然后再将其变换到坐标表象和动量表象中讨论其分布函数。它具有计算简便,物理概念清晰之特点 相似文献
99.
A 10-GHz CMOS ring oscillator that employs a multi-pass technique for boosting its frequency is proposed in this paper. The
proposed circuit allows the tuning gain to be lowered by deploying the coarse/fine frequency tuning whilst maintaining wide
frequency coverage. The small signal model of the proposed delay stage and the circuit operation are discussed in this paper.
The time-variant analysis presented permits accurate prediction of the frequency tuning characteristic and the results have
been verified by simulation. The phase noise analysis is also discussed in detail to provide better insight to the noise that
is contributed by each transistor. The calculated results agreed well with that of the simulations.
Hai Qi Liu was born in Jiangsu, China, in 1979. He received the B.S. and M.Sc. degrees, both in electrical engineering from the Tianjin
University, Tianjin, China, in 2000, and Tongji University, Shanghai, China, in 2003, respectively. He is currently working
toward the Ph.D. degree at the Nanyang Technological University, Singapore. His research focuses mainly on the design of fully
integrated oscillators and Phase-Locked Loops for optical communication applications. His research interests also include
RF frequency synthesizers and RF front-end designs for wireless applications.
Wang Ling Goh obtained both her B.Eng and Ph.D. degrees from the department of Electrical and Electronic Engineering at the Queen’s University
of Belfast (QUB) in United Kingdom. When working on her Ph.D., she was also engaged as a research associate at the Northern
Ireland Semiconductor Research Centre (NISRC) at QUB. Dr Goh joined the School of Electrical and Electronic Engineering at
the Nanyang Technological University (NTU) in Singapore as a lecturer in January 1996. She is now an Associate Professor in
the Division of Circuits and Systems, School of Electrical & Electronic Engineering. Dr Goh has to-date co-authored 1 book,
filed 13 patents (granted), and published about 60 research papers in international conferences and journals. Her research
interests are in areas of silicon device processing technologies as well as digital and mixed-signal IC designs.
Liter Siek received the B.A.Sc. degree from University of Ottawa, Ontario, Canada; the M.Eng.Sc. from University of New South Wales,
Sydney, Australia; and the Ph.D. from Nanyang Technological University, Singapore. From 1981 to 1983 he was employed in several
companies in the area of automation and control. From 1983 to 1985, he was with SGS, currently known as ST Microelectronics
situated in Castelletto, Milan, Italy, where he worked in the central R&D Laboratories for Linear IC. From 1985 to 1987, he
was with the same company situated in Singapore’s Asia Pacific Design Center. Since October 1988, he has been with Nanyang
Technological University. His research interests are in the design of bipolar, CMOS and BiCMOS analog/mixed signal ICs. In
addition, he has authored and co-authored 53 international journal/conference technical papers. 相似文献
100.
Zhi-Qiang Lu Jian-Guo Ma Feng-Chang Lai 《Analog Integrated Circuits and Signal Processing》2006,49(1):27-30
A 900-MHz two-stage CMOS voltage controlled ring oscillator (VCRO) with quadrature output is presented. The circuit is designed
in a 0.18-um CMOS technology and operated on a 1.8-V supply voltage. The VCRO have a tuning range of 730 MHz to 1.43 GHz and
good tuning linearity. Between 0 V and 1.1 V of control voltage, the gain of VCRO is around −620 MHz/V. At 900 MHz, the phase
noise of the VCRO is −106.1 dBc/Hz at 600-KHz frequency offset with power consumption of 65.5 mW. 相似文献