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41.
S. Mitatha 《Optik》2010,121(14):1313-1316
We firstly propose a new system for simultaneous fast and slow light generation using a soliton pulse propagating within the nonlinear micro-ring resonators. The nonlinear Kerr effect induces the spreading frequency bands within the micro-ring device, where the chaotic filtering characteristics can be employed using the appropriate micro-ring parameters. Results obtained have shown that the wide spreading of frequency bands can be generated and selected to form the optical wireless communication links. In this work, the selected down-link and up-link frequency bands are 500 MHz and 2 GHz, respectively. The proposed system can be implemented within the mobile telephone hand set, where the two different frequency carriers within the same frequency bands can be selected to form the up-down-link converters, which means that the frequency converter can be performed within a single system. 相似文献
42.
在波束波导和反射面天线的馈源应用中, 为了产生低副瓣且方向图等化的高斯波束, 需要将高功率微波转换为准高斯模HE11模辐射. 本文利用弯曲圆波导可同时从TM01模产生TE11模和TM11模的原理, 提出了采用双弯曲过模圆波导结构直接将TM01转换为HE11的模式变换器, 避免了常规微波领域中首先将TM01转换为TE11再用波纹式或半径渐变式TE11-HE11转换器转换为准高斯波束功率容量不足或尺寸过长的不足. 基于模式耦合理论和Taguchi优化算法对模式变换器的弯曲半径、相移直端长度及引入位置进行了优化, 使输出的TE11和TM11成一定比率, 以组成HE11模式, 并对设计的模式变换器进行了全电磁波仿真分析, 结果表明输出波束的标量高斯含量在9.05–9.8 GHz范围内均高于99%, 理论功率容量可达4.5 GW.
关键词:
高功率微波
模式耦合理论
Taguchi优化算法
模式变换器 相似文献
43.
An experimental study of the mechanism for chemical etching of fission fragment tracks in the natural mineral fluorite is described. A systematic search showed that a 3:1 mixture by volume of sulphuric to hydrochloric acids was a most appropriate etchant. Experiments directed at determining the etching efficiency as a function of solvent temperature are also discussed. The preferential track etch ratioVt/Vg, the track length and the track density all depend upon the time and temperature of annealing. It is variations of the fission track density in fluorite, with etching time and annealing temperature, which make possible an overall geophysical interpretation of annealing data for the mineral in terms of the paleoisotherm of its intrinsic fission track clock. An interactive image analysis system INTIMAN, assembled for the swift and automatic readout of fission fragment track measurements, in both crystalline and non-crystalline materials, is described. Normal procedures for measuring and analyzing tracks are outlined. 相似文献
44.
Recently an accelerated iterative procedure was studied for solving a coupled partial differential equation system in interphase heat transfer to improve some existing iterative procedures in the literature. In that procedure, at each step of the iteration one has to evaluate the derivative of a well-known function at a new point. In this paper, an alternative approach is proposed in which one has to evaluate the derivative only once throughout the procedure. The proposed new iterative scheme also has the same order of convergence and takes lesser number of iterations for certain benchmark problems. An interesting theoretical study on the monotone convergence as well as error estimate of the proposed iterative procedure are provided for continuous as well as discretized problems. The proposed iterative procedure also supplements the existence and uniqueness of the solution in both the cases. A comparative numerical study is also done to demonstrate the efficacy of the proposed scheme. 相似文献
45.
An incorporation of few weight percentage of n-type zinc oxide (ZnO) on the surface of yellow-emitting fluorescent polymer under mild conditions was demonstrated. Here, a deep level emissive ZnO was selectively deposited on the surface of fluorescent polymer via a simple chemical deposition bath method, at relatively low temperature. The polymer-zinc oxide hybrids, consisting of uniform nanosized spherical fluorescent polymer, having mean diameter ca. ∼500-700 nm were subjected as core molecules capped with different weight ratio of ZnO on the surfaces were prepared successfully. The relative photoluminescence emission efficiency was drastically enhanced as two-fold with just 4 wt% of ZnO incorporation and also more than 10-fold improvement in 50 wt% of ZnO content with respect to pure fluorescent polymer. Bright and efficient white light-emitting devices have been fabricated with these hybrid materials, such as luminescence converter light-emitting diodes (LUCO LEDs), using commercially available GaN LED (460 nm), as a primary pumping source. A device containing 20 wt% of ZnO incorporated hybrid material (2 wt%) exhibits nearly pure white light, having Commission Internationale de I’Eclairage coordinates of (0.30, 0.36) and total luminous flux of 1.80 lm, at an operating voltage of 20 mA. The lifetime measurement data of fabricated device containing polymer-ZnO hybrid materials showed significant improvements over the pure counterpart, due to the “caging effect” of the ZnO shell, which can reduce the self-quenching of the polymer molecules in the core. 相似文献
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HT-7U等离子体位移快控电源设计 总被引:1,自引:0,他引:1
针对HT-7U装置等离子体位移快控电源大电流快速响应要求,提出了一种基于电流型变流器的快控电源(FCPS)设计新方案。该方案采用交-直-交拓扑结构,即网侧采用电流型PWP整流器设计。以获得稳定的直流电流及网侧单位功率因数正弦波电流控制;负载侧则采用电流型H桥逆变器设计以实现负载电流的快速跟踪控制。移相PWM控制策略在实现多组变流器并联运行的同时,提高了变流器的等效开关频率控制,从而改善了电流波形品质。模拟系统实验论证了方案的正确性。 相似文献
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