Channel Modeling Based on Interference Temperature in Underlay Cognitive Wireless Networks

Cognitive radio based dynamic spectrum access network is emerging as a technology to address spectrum scarcity. In this paper, the authors assume that the channel is licensed to some primary (licensed) operator. They consider a sensor network with cognitive radio capability that acts as a secondary (unlicensed) network and uses the channel in underlay mode. The secondary network uses interference temperature model to ensure that the interference to the primary devices remain below a predefined threshold. They use Hidden Markov Model (HMM) to model the interference temperature dynamics of a primary channel. The HMM is trained using Baum-Welch procedure.