Cooperative Sensing Scheduling for Energy-Aware Cognitive Radio Networks

Cooperative spectrum sensing, which provides an effective approach to improve the sensing performance and better exploit the spectrum opportunities, is an important technology to enable the implementation of Cognitive Radio Networks (CRNs). The most fundamental and practical problem of cooperative spectrum sensing is: how to appropriately schedule Secondary Users (SUs) to sense multiple primary channels? In this paper, we study this Cooperative Sensing Scheduling (CSS) problem in the context of energy-aware CRNs. The CSS problem is modeled as a combinatorial optimization problem with the objective of improving energy efficiency in CRNs. Different from general approaches which employ heuristic methods to solve such combinatorial optimization problem, we propose a theoretical framework and analytically study the problem. Some interesting and important properties are obtained, while a simple but robust algorithm that guarantees to find the optimal solution efficiently is developed based on our findings. By observing that our problem shares a general form as studied in many other topics, we also discuss about the potential applications of our framework.