An Ecological Model for User Population Dynamics in Cognitive Radio Networks

Abstract

Understanding the population and capacity dynamics of users in a cognitive radio (CR) system is important for planning their coexistence, sharing resources, network stability and achieving spectral efficiency. Rich analytical models are required for planning CR systems. The interaction among different classes of primary users and secondary users sharing the radio spectrum is analogous to the interaction among different species coexisting in an ecosystem. Therefore, this work employs ecological models based on the differential Lotka-Volterra equations to determine the population dynamics, interactions and spectrum management of the different users in a CR system employing adaptive modulation and coding (AMC). The performance dynamics of the system are investigated in terms of the transient behavior, the number of species and system stability.