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This article presents the results of an experimental study of a structure with single modal reservation (MR). The decomposition of an ultrawideband (UWB) pulse in such a structure before and after failures has been demonstrated for the first time. For this case, authors used two bell-shaped pulses with a total duration of 0.15 and 1.5 ns. The frequency dependences of the transmission coefficient magnitude |S21| were measured for the manufactured prototype in the range from 10 MHz to 18 GHz. The results demonstrate that the structure before and after failures acts as a low-pass filter. To confirm the results of the experiment, its numerical simulation was carried out using two approaches: quasistatic and electrodynamic. In doing so, we took into account losses in conductors and dielectrics. To numerically estimate the criticality of the voltage waveforms obtained during the experiment at the output of the reserved circuit before and after failure, we calculated the N-norms. The simulation and experimental results in the time and frequency domains agree quite well. It was shown experimentally that after failures the maximum changes in the cutoff and the resonant frequencies are 45% and 19%, respectively. This suggests that after failures, the results may not coincide with the predicted ones, which must be taken into account when designing real structures with MR. It was found that in the time domain after failures, the maximum amplitudes of the decomposition pulses at the far-end of structure with a single MR change, and these changes depend on the duration of the UWB pulse at the input. This influence is explained by the length of the traces to SMA connectors. If the double delay in the trace is greater than the total pulse duration, then after failures, the amplitudes will not change, since the reflected pulses will not be superimposed on the main ones. However, as the length increases, the UWB pulse will be superimposed on the main ones and will change the maximum amplitude. This effect must be taken into account during design process as it can affect the interference immunity and functional safety of the device. This is shown in the analysis of N-norms. [ABSTRACT FROM AUTHOR]

The article presents the results of calculating time responses of a meander line (ML) turn to pulse excitation. The responses were calculated at the ML nodes analytically and numerically, and demonstrated coincidence. Besides, the created prototype of the ML turn was measured and showed good qualitative and acceptable quantitative agreement with the simulation results. Analytical models were found to be promising since they may significantly accelerate the design of such MLs in contrast to numerical methods which provide costly multivariate simulation of the time response during optimization. [ABSTRACT FROM AUTHOR]

An analytical model is proposed for evaluating shielding effectiveness (SE) of a rectangular enclosure populated with conducting plates. The conducting plates are considered as capacitive diaphragms that fill the width of the enclosure, and SE is calculated using the equivalent circuit of the enclosure. The letter presents an improved approach to evaluating enclosures populated with printed circuit boards (PCBs) or plates coated with a composite or radar-absorbing material. The evaluation of the model error was performed when the plate height changed. Both this model and finite element method were used to calculate the SE for enclosures populated with conducting plates, PCBs and the plate coated with a magnetic composite material. The results obtained in the range up to 1 GHz are in good agreement. [ABSTRACT FROM AUTHOR]

Examines the problem of far-end crosstalk reduction in double-layered dielectric interconnects. Usage of the possibilities in printed circuit boards; Simulation of far-end crosstalk waveforms; Assumption of the calculation of lines parameters.

The paper presents some experimental results on unusual propagation of an ultrawide band (UWB) pulse in low-voltage three-conductor power cables. For cables of flat cross section, the results confirm the possibility of modal decomposition of the pulse into two low level pulses. However, this phenomenon does not occur in cables of circular cross section. [ABSTRACT FROM AUTHOR]