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Far-end crosstalk (FEXT) in typical high-speed printed circuit board striplines is primarily attributed to dielectric inhomogeneity. In this article, the inhomogeneity problem is comprehensively addressed by a novel algorithm that characterizes the dielectric constants (DKs) of glass fibers and epoxy resin. In contrast to other methods, the proposed approach enables one to assess the impact of geometrical parameters on stripline FEXT and to estimate DK core and DK prepreg based on DK glass and DK resin values extracted through analytical expressions. Full-wave simulations and real-board measurements are conducted to verify the proposed approach. 

De-embedding techniques have been introduced to evaluate the real electrical performances of a device under test (DUT), e.g., the traditional thru-reflect-line and short-open-load-thru standards, where the transfer matrix (T-matrix) and its inverse form are adopted in the mathematical process. A DUT may have three coupled ports in the fields of radio frequency and electromagnetic compatibility. The symmetry in the corresponding S-matrix breaks down, because the numbers of incident and reflected ports are not equal. Thus, it leads to a nonsquare T-matrix by definition. Given that the inverse expression of a nonsquare matrix does not exist, the conventional de-embedding methods are inapplicable for a coupled three-port network. In this article, a de-embedding algorithm, which is feasible for coupled three-port devices, is proposed and verified through the measurement. The proposed de-embedding technique may also be applied on devices with more than three ports. 

An accurate and broadband modeling methodology for a typical permanent magnet synchronous motor (PMSM) in a vehicular three-phase braking system is proposed for the first time to improve the accuracy of induced electromagnetic interference (EMI) in three-phase motor systems. The proposed model is verified by measurement from dc to 120 MHz both in common- and differential-mode current measurement of the three-phase motor under study. The proposed model can be used in analysis and prediction of the electromagnetic noise of the motor-drive braking system. The model can also be incorporated into frequency- and time-domain simulations. The modeling approach is based on the vector fitting technique of measured three-phase motor impedance and S-parameter, where the three-phase PMSM is modeled as a multiport device. In addition, the proposed modeling method for the PMSM can be used for different types of three-phase motors for EMI simulations and analysis.