Structural Stochastic Multiresonance in Hierarchical Networks

Systems with a structure of hierarchical networks, consisting of simple units placed in the nodes and interacting along the edges of the network, are ubiquitous in the modern society and economy. In this paper the problem of signal detection and transmission in such systems in the presence of noise is analyzed from the point of view of stochastic resonance. As examples simple tree-like and more complex Ravasz-Barabási networks of interacting threshold elements are considered. It is shown that stochastic multiresonance is often observed, a phenomenon characterized by the presence of two or more maxima of the output signal-to-noise ratio as a function of the input noise intensity. The origin of the additional maxima, which occur for small noise intensities, can be related to the structure of the interactions, thus the observed phenomenon is an example of structural stochastic multiresonance.