【作者】 黎淑兰；

【导师】 刘元安；

【作者基本信息】 北京邮电大学 ， 密码学， 2005， 博士

【摘要】 伴随着数字化时代的到来,电子设备中使用的信号频率越来越高,信号的上升沿越来越陡峭,元器件的集成度也越来越大,这就使得电子设备的电磁兼容问题随之变得十分突出,如何保证各种电子设备在复杂、恶劣的电磁环境中正常地工作成为当前研究的热点。印刷电路板作为电子设备不可缺少的部分,它的电磁兼容性能的好坏将严重影响电子设备的性能,因此,对印刷电路板进行电磁兼容研究变得十分迫切。本文针对印刷电路板电磁兼容设计的具体理论和实际问题,如敏感线路保护带的电磁干扰抑制效应及优化、印刷电路板走线的天线效应等,建立了可靠的理论模型,并采用全波分析方法FDTD 开展了深入和全面的研究。本文的主要工作和创新如下:1. 完成了适合印刷电路板上微带电路分析的3-D 各向异性的PML吸收边界条件、集总元件、局部网格细化以及微带线辐射效应的近场-远场转换的FDTD 模型的提取和实现。更多还原

【Abstract】 With the coming of digital age,electromagnetic compatibility (EMC) is agrowing critical problem with electronic devices using the higher frequency,higher integration densities and more sharp signal rise-time. How to make thediversified electronic devices operation reliably in complicated and worseningelectromagnetic environment has spurred a lot of interest in recent years. Theelectromagnetic compatibility of printed circuit boards (PCB), which is thenecessary for electronic devices, can influence the performance of the devicesgreatly, so the electromagnetic compatibility investigation on PCB is a matterof great urgency.In this paper the EMC problems such as the electromagnetic interferencesuppression and optimization effectiveness of guard lines for victim lines andthe antenna effectiveness of PCB traces are investigated and the theoreticalmodels for analysis are extracted. The finite difference time domain (FDTD)method has been used to simulate the situation and the approach ofappropriate placement of guard lines is obtained. The contributions done inthis paper are as follows: 1. The FDTD models suitable for analysis of microstrip circuits areestablished,these models include various aspects such as 3-dimensionanisotropic perfectly matched layer(PML) absorbing boundary condition, theFDTD simulation of lumped element, the subgridding method and the nearzone to far zone transformation for radiation computation. 2. Under the assumption that conductor and medium are all lossless,influence of the parameters of guard lines on crosstalk between coupledmicrostrip lines is investigated, such as the diameter, spacing of via holes, theseparation between guard line and signal line and the permittivity of substratemedium. The larger diameter, the shorter separation between guard line andsignal line, and the smaller permeability, the lower the crosstalk. The spacingof via holes has little effect on crosstalk reduction but if the via spacing is toolarge resonance may occur in operation frequency. However, the resonancecan be avoided by ensuring that the spacing between the adjacent vias is lessthan half wavelength of the highest operation frequency component of thesignals in the aggressor lines. 3. The crosstalk suppression effectiveness of the height, length and thestart location of guard lines is investigated. The higher via holes, longer theguard line, the lower the crosstalk. The start location of guard lines hassignificant effect on near-end crosstalk and to reduce the crosstalk the guardlines should start from near-end.更多还原