Time and Frequency Domains Evaluation of Crosstalk on Differential Lines with Meander Structure

The meander structures in printed circuit boards (PCBs) are designed to compensate for signal skew in differential transmission lines. They introduce heterogeneous impedance, raising concerns about signal integrity. Despite the known issues, the impact of meander structures in differential lines, particularly their influence on adjacent lines, has not been investigated. In this study, we analyze the effects of meander structures on both near-end Crosstalk (NEXT) and far-end Crosstalk (FEXT) through 8-port mixed-mode S-parameters and step pulse analysis, using finite-difference time-domain simulations. Our findings indicate that in NEXT assessments, voltage fluctuations are primarily attributable to reflections from the meander structure. In contrast, FEXT is mitigated as the meander structure prolongs the rise time of signals propagating through the aggressor line.