Volterra model of a class of two-memristor circuits

The Volterra series approach represents a powerful theoretical tool to model the dynamical behaviour of nonlinear systems. In principle this paradigm characterizes completely the dynamics of a system upon specification of an infinite set of kernels. In practical implementations only a finite set of kernels may be considered. The accuracy level of the Volterra series-based modelling depends on the number of elements in this set. The system output is then expanded as a finite algebraic sum of multi-dimensional convolution integrals involving system input and kernels. Memristors are nonlinear dynamical devices which promise to improve and/or extend the functionalities of state-of-the-art electronic systems. However, classical circuit and system theory techniques for modelling linear devices are not suitable for them. The Volterra series paradigm has been recently adopted to model a class of one-memristor circuits. In this work the technique is extended to the analytical representation of two-memristor circuits. The agreement between Volterra series-based predictions and numerical integration results on an exemplary circuit from the class provides evidence for the accuracy of the modelling paradigm.