Modeling and Design for Electromagnetic Compatibility Issues of Slot-Crossing Signal Lines

• Main Authors: Hao-Hsiang Chuang, 莊皓翔
• Other Authors: Tzong-Lin Wu
• Format: Others
• Language: en_US
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/46717570195927451689

博士 === 國立臺灣大學 === 電信工程學研究所 === 100 === The dissertation provides solutions and modeling methods for electromagnetic compatibility problems caused by slot-crossing signal traces. Based on the transmission line models, equivalent circuit models for the signal traces were created, which transformed physical configurations into electrical behavior. With the help of the constructed models, low-cost solutions have been proposed to solve the unwanted crosstalk, common-mode radiation and lossy material problems when high-speed signals cross slotted reference plane. In the beginning, the crosstalk between signal traces crossing the same slot is first investigated. By connecting an open-circuited microstrip line in parallel with the slotline between the crossing signal lines, a branched reflector technique is proposed to suppress the crosstalk due to the inter-symbol interference. The design methods both for low- and high-frequency transmission have been proposed and validated by the simulation and experimental results. Second, a grounded resonator technique is designed to reduce common-mode radiation and mode conversion, which are resulted from common-mode noise striding across the slotted plane. By properly linking the open-circuited transmission lines with the slotline, the common-mode transmission can be controlled to prevent excitation of antenna-like slotline. This low-cost solution makes the radiated electric field to be effectively decreased from 2.29 to 3.48 GHz, which is consistent to the designed passband. Finally, a differential-mode equalizer with broadband common-mode suppression is proposed. To the best knowledge of the author, these dual functions are the first time to be integrated in a single structure. Through suitably connecting the coupled slotlines with the differential line structure, the terminated resistors at the end of coupled slotlines provide the equalization and absorption for differential-mode transmission and common-mode noise, respectively. With the experimental validation, the eye-diagram of differential-mode transmission at 8 Gbps has been greatly improved comparing that without the designed configuration.