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Communication errors can be caused by transient electromagnetic disturbances, making the related protection and avoidance measures highly demanding. In this article, we propose a statistical method to infer error mechanisms of serial communication errors caused by repetitive electromagnetic disturbances. An experimental investigation has been conducted by introducing crosstalk disturbances on the transmission cable, resulting in various communication errors. To determine the corresponding failure mechanism for these errors, a hypothesis test method is introduced. First, the bit-flip error on the basis of the known mechanism is simulated through the Monte Carlo method, so that a null hypothesis can be established. Then, by applying a modified chi-squared test, researchers can investigate the influence of multiple pulses on the occurrence probability of bit errors. As a result, nonlinear effects such as energy saturation or accumulation of the transceivers can be discovered. The validated results show that the proposed method has a good performance to determine the known mechanisms of communication errors and infer new regularities with a given significant level.

The traveling-wave Marx generator was first proposed by Carl Baum to analyze the switch-closure propagation process in fast pulsed-power systems. To improve the performance of the transistorized sub-nanosecond pulse generator, the traveling-wave Marx circuit with inter-stage transmission lines is studied. Simulations indicate that the delay time and the impedance of inter-stage transmission lines [microstrip lines on printed circuit board (PCB)] are main factors affecting the pulse waveform. Based on it, the series connection of modularized Marx circuits is proposed, which has the advantages of adjustable amplitude and bendable circuit layout. A compact high-amplitude pulse generator is developed with the amplitude of 8.2 kV, the rise time of 150 ps, and the PCB length of 35 cm. For higher pulse repetition rate, the heat dissipation design of PCB is necessary; however, due to the variations in the microstrip line structure, the commonly used metallic heat sink may cause a significant decrease in pulse amplitude. Thus, a novel heat dissipation design is proposed by optimizing the layout of metallic sinks and introducing heat-conducting ceramic sinks. A high-repetition-rate pulse generator is developed with the maximum pulse repetition rate of 600 kHz, the amplitude of 1.1 kV, and the rise time of 160 ps.

A lot of work has been done for the effects evaluation of electronic equipment due to high-power electromagnetic environments. The focus of the evaluation usually stays on whether the effects occur or not (“1” or “0”) during tests. However, in addition to such kind of either-or effects, multilevel effects happen in many practical cases as well. In this paper, we propose a kind of statistical approach for the evaluation of multilevel effects. By means of multinomial regression, the occurrence probabilities of each level of effects can be estimated simultaneously. Through maximum likelihood estimation (MLE), both the Softmax model and the mutually independent normal distribution assumption model are built and solved in a numerical way. We also talk about how the data affect the goodness of the regression. As a consequence, the Monte Carlo simulation gives a quasi-function relationship about model stability and estimation error. A case study on computer communication system has been conducted in the laboratory to assess the validity and applicability of the proposed models. The result is satisfactory for the three-level cases and gives all the probability prediction of the malfunction occurrences.

This paper proposes an effective test setup and method for quantitative determination of critical parameters of surge protective devices (SPDs) when excited by nanosecond level pulse (normally rise time less than 2 ns). The experimental results of SPDs validate the accuracy and reliability of the proposed method. By using the proposed method, the response time and time-varying response characteristics can be evaluated; meanwhile, the incoming voltage and residual voltage of SPDs can be retrieved by simple mathematical operations. These parameters obtained from the proposed method are critical to the device selection when designing the fast response protective module and examining the performance of SPDs by the manufacturers.