Chaotic phenomena in nonlinear circuits with time-varying resistors

Four simple nonlinear circuits with time-varying resistors are analyzed. These circuits are a kind of parametric excitation circuit, and chaotic attractors are observed in three circuits. In order to analyze these circuits a degeneration technique is used, that is, diodes in the circuits are assumed to operate as ideal switches. Thereby the Poincare maps are derived as one-dimensional maps and chaotic phenomena are well explained. Moreover, the justifiability of the analyzing method is confirmed by circuit experiments.<
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