平面切换对信号传输特性影响的一种分析方法  

Analysis of the signal transmission characteristics with switching plane

作　　者：温舒桦[1] 张金玲[1] 吕英华[1] 曹新宇[1] 郑鑫[1] 

机构地区：[1]北京邮电大学电子工程学院,北京100876

出　　处：《电波科学学报》2015年第5期999-1003,共5页Chinese Journal of Radio Science

基　　金：国家自然科学基金(61171051);北京市自然科学基金;北京市教育委员会科技计划重点项目(KZ201310028032)

摘　　要：采用"场"、"路"结合的方法研究了多层印制电路板参考平面的切换对信号完整性的影响.分析了过孔转换结构中返回电流的路径,通过"场"的方法获得两参考平面间的瞬态阻抗.将过孔转换结构等效为二端口网络,推导了基于等效电路拓扑结构的S参数与节点电压的关系,获得S参数的计算公式.计算了5GHz内不同的过孔半径和参考面间距的回波损耗与插入损耗.结果表明:返回电流所受到的阻抗随参考平面间距的减小.而减小信号过孔的半径越小,回波损耗就越小,插入损耗越大,过孔转换结构对信号完整性的影响也越小.计算结果与全波有限元电磁仿真的结果基本吻合.The influence of signal integrity caused by the switch of reference planes in multilayer printed circuit boards was evaluated by the method of combining ＂field＂and＂circuit＂.Firstly,the path of return current in via transition structure has been analyzed,and the transient impedance between two reference planes was obtained by＂field＂method.Then the relationship between Sparameter and node voltage based on equivalent circuit topological structure has been derived by equalizing via transition structure to two-port network.The computational formula of Sparameter has been obtained.Finally,the return loss and insertion loss have been calculated with different via-radius and planes spacing.Research results show that the impedance of return current is decrease following the decreasing size between two reference planes.The return loss is lesser and the insertion loss is greater when the radius of via decreased,the impact of signal integrality caused by via transition structure was decreased.The computed result is accordant with the result of electromagnetic simulation.

关 键 词：多层印制电路板 过孔转换结构 二端口网络 S参数 信号完整性 

分 类 号：TN958.93[电子电信—信号与信息处理]