期刊文献+
共找到2篇文章
< 1 >
每页显示 20 50 100
基于插入损耗的噪声源阻抗修正计算方法 被引量:13
1
作者 张佳佳 张逸成 +2 位作者 韦莉 叶尚斌 姚勇涛 《电工技术学报》 EI CSCD 北大核心 2015年第4期80-87,共8页
为了使EMI滤波器能够实现有效的插入损耗,需要考虑噪声源阻抗的频谱特性。电压插入损耗法是最简单的测试噪声源阻抗的方法。本文分析了传统的电压插入损耗法在实现过程中采用的假设条件,部分假设在数学上并不严格成立,相应的简化近似计... 为了使EMI滤波器能够实现有效的插入损耗,需要考虑噪声源阻抗的频谱特性。电压插入损耗法是最简单的测试噪声源阻抗的方法。本文分析了传统的电压插入损耗法在实现过程中采用的假设条件,部分假设在数学上并不严格成立,相应的简化近似计算可能导致较大误差;甚至有些计算结果会与假设条件矛盾,进而导致计算结果无效。在不改变传统插入损耗法的测试方案的前提下,对噪声源阻抗的计算方法进行修正,推导了源阻抗幅值的精确解析表达式,进而确定源阻抗幅值的最大值和最小值。解析计算结果经过数学验证成立。在此基础上,以电动汽车用DC-DC变换器为测试对象,实现了源阻抗幅值的测试和计算,验证了该方法的有效性和适用性。通过该测试和设计实例的分析可以发现,改进的电压插入损耗法可以获得更精确的噪声源阻抗,避免滤波器的过设计,便于滤波元件的设计和选型,并为滤波器体积、重量等的优化提供帮助。 展开更多
关键词 噪声源阻抗 电压插入损耗 EMI滤波器 阻抗失配
下载PDF
Design of a Polymer Directional Coupler Electro-Optic Switch with Low Push-Pull Switching Voltage at 1550nm
2
作者 郑传涛 马春生 +2 位作者 闫欣 王现银 张大明 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第11期2197-2203,共7页
A polymer directional coupler (DC) electro-optic switch with push-pull electrodes and rib waveguides is designed based on the conformal transforming method, image method, coupled mode theory, and electro-optic modul... A polymer directional coupler (DC) electro-optic switch with push-pull electrodes and rib waveguides is designed based on the conformal transforming method, image method, coupled mode theory, and electro-optic modulation theory. Its structure and principle are described, the design and optimization are performed, and the characteristics are analyzed, including the coupling length, switching voltage, output power, insertion loss, and crosstalk. To realize normal switching function,the fabrication tolerance,wavelength shift, and coupling loss between a single mode fiber (SMF) and the waveguide are discussed. Simulation results show that the coupling length is 3082μm; the push-pull switching voltage is 2.14V;and the insertion loss and crosstalk are less than 1.14 and -30dB,respectively. The proposed analytical technique on waveguides and electrodes is proven to be accurate and computationally efficient when compared with the beam propa- gation method (BPM) and the experimental results. 展开更多
关键词 electro-optic switch push-pull electrodes coupling length switching voltage insertion loss CROSSTALK
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部