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1.
The pole-zero diagram is a tool that has been widely employed in digital and electronic filter design. It greatly facilitates filter design by producing a simple and direct visualization of parametrical behaviors and general spectral characteristics. In this paper, we propose new methods of applying pole-zero diagrams to photonic filter design, aimed at tailoring spectral characteristics. In particular, we demonstrate the effectiveness of this method in designing ring resonator-based filters for application to optical wavelength interleavers and deinterleavers. We show that there exist close relations between the pole-zero diagram of an optical filter and its wavelength response, and derive pole-zero diagrams for filters with various ring resonator configurations. Further, we propose a novel graphical technique using pole-zero diagrams for optimizing filter performance. As a practical example to demonstrate the effectiveness of the pole-zero approach, we present a new wavelength interleaver design with low crosstalk. This design was realized by superimposing the pole-zero diagrams of parallel and series-coupled ring resonator arrays.  相似文献
2.
Robust Fault Detection of Markovian Jump Systems   总被引:2,自引:0,他引:2  
This paper deals with the problem of observer-based robust fault detection for both continuous- and discrete-time linear Markovian jump systems with an unknown input. By using a fault detection filter as residual generator and a proposed performance index as objective function, the robust fault detection filter design is formulated as an optimization problem. A sufficient condition to solve this problem is established in terms of the feasibility of certain matrix inequalities, which can be solved via iterative linear matrix inequality (LMI) algorithms. The residual evaluation problem is also considered. A numerical example is given to illustrate the effectiveness of the proposed techniques.  相似文献
3.
基于DSP的半导体激光器电源设计   总被引:2,自引:0,他引:2  
张前进  朱晓  丁芃 《电子科技》2005,(10):34-38,43
介绍了一种采用基于TMS 32 0F24 07型号DSP控制的半导体激光器电源的构成和原理,提出了一种新的自整定智能PID的优化算法,结合模块化的VICOR开关电源、DSP控制电路、信号采集、放大电路和保护电路等部分,从而实现半导体激光器的可靠运行和工作电流的稳定精确输出.  相似文献
4.
平行缝焊与盖板   总被引:2,自引:1,他引:1  
在一些特殊环境条件下使用的各种电子元器件,需要进行密封封装,以防止器件中的电路因潮气、大气中的离子、腐蚀气氛的浸蚀等引起失效。另外在封装时可以充以保护气体来降低封装环境湿度,进行气密性封装以延长器件的使用时间。文章通过在SSEC(Solid State Equipment Company)M-2300型平行缝焊机上进行缝焊实验发现,盖板与平行缝焊的关系是相当重要的。在管座性能稳定的情况下,盖板质量的好坏直接影响着器件的气密性。  相似文献
5.
We report on a high power output quasi-continuous-wave nanosecond optical parametric generator (OPG) of congruent periodically poled lithium niobate (PPLN) pumped by a 1 064 nm acousto-optically Q-switched Nd-YVO4 laser (duration. 70 ns,repetition rate:45 kHz,spatial beam quality M2〈 1,3). The OPG consists of a 38.7 mm long PPLN crystal with a domain period of 28.93 μm. With 5.43 W of average pump power the maximum average output power is 991 mW at 1 517.1 nm signal wave of the PPLN OPG.  相似文献
6.
钌基厚膜电阻导电机理的国内外研究状况   总被引:1,自引:0,他引:1  
丁鹏  马以武 《电子器件》2003,26(3):264-268
较全面的对国内外厚膜电阻导电机理的研究状况进行了综述,介绍了均匀分布模型,均匀通道模型。非隧道势垒模型,隧道势垒模型及其优缺点。对隧道壁垒模型进行深入的分析和讨论。并运用这些理论解释了厚膜电阻的温度特性、电场特性和热电效应。  相似文献
7.
White-light interferometry (WLI) is an efficient method for measurement of strain, twist, temperature, and many other physical parameters in fiber-optic measurement systems. [1-10]. It can provide large dynamic range and high accuracy for absolute measurements of displacement and strain. Meanwhile, it is not sensitive to optical power fluctuation [6]. WLI based on optic sensors are immune to electromagnetic interference, suitable for harsh environments and compat- ible with optical fiber dat…  相似文献
8.
使用格兰-泰勒棱镜偏振耦合的1 kW大功率半导体激光器   总被引:1,自引:1,他引:0  
大功率量子阱半导体激光器输出为线偏振光,而格兰-泰勒棱镜具有双折射性质,能将两种偏振方向相互垂直的光区分开.如果将格兰-泰勒棱镜反方向使用,则能将两个偏振方向的光耦合输出.使用两个中心波长808 nm,输出功率600 W的半导体激光堆栈,一个堆栈的输出光经过1/2波片后偏振方向旋转90°,另一个堆栈偏振方向保持不变,经过格兰-泰勒棱镜做偏振耦合后合成一束.分别经过快慢轴准直、聚焦和慢轴消球差后输出,其中聚焦镜f=100 mm.在工作电流130 A时,电光转换效率约为43%.使用UFF100激光光束质量诊断仪测量,焦斑呈矩形分布,焦斑面积为0.547 mm×5.0 mm,快轴光参积Kf=26.1 mm·mrad,最大输出功率1 kW,激光器系统工作稳定.  相似文献
9.
In this paper, a novel heterodyne detection technique of rotation rate is described. This technique uses highly birefringent single-mode fiber and an electrooptic frequency shifter for a heterodyne interferometric system, and thus releases the use of acoustooptic devices and also the nonreciprocity which usually exists in a heterodyne fiberoptic gyroscope. Initial experimental results show a good linearity of the scale factor.  相似文献
10.
We report the development of a novel and simple technique for fabricating polymer optical fibers of good optical quality for special device applications. This technique aims at polymer fibers doped with various functional organic materials. On the basis of the technique, step-index polymer optical fibers doped with laser dyes have been fabricated. High-gain and high-efficiency optical amplification has been achieved in a Rhodamine B-doped polymer fiber with a low pump power of less 1 kW and pulse width 5 ns. Because a high dye concentration is used, the optimal wavelength range of optical amplification in this fiber is significantly red-shifted toward the center of the communication window (at 650 nm wavelength) of methyl methacrylate-based polymer optical fiber. The shift is from the originally 560 and 590 nm to presently 610 to 640 nm. We also present experimental results that show good photostability of the Rhodamine B-doped polymer fiber, compared with those recently reported in the improved polymer material systems. From the experimental observation, we identified the thermally induced bleach of dye molecules as the major contributing factor to the lifetime of our material system  相似文献
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