A rollout-based joint spectrum sensing and access policy for cognitive radio networks with hardware limitations
Lingcen Wu, Wei Wang, Zhaoyang Zhang, Lin Chen · 2012
The practical hardware limitations bring technical challenges to cognitive radio, e.g. limited capability of spectrum sensing and certain frequency range of spectrum access. In this paper, we propose a rollout-based joint spectrum sensing and access policy incorporating the hardware limitations of both sensing capability and spectrum aggregation, in which the optimal policy is shown to be PSPACE-hard. Two heuristic policies are proposed to serve as base policies, based on which the developed rollout-based policy approximates the value function and determines the appropriate spectrum sensing and access actions. We establish mathematically that the rollout-based policy achieves better performance than the base policy. We also demonstrate that the low-complexity rollout-based policy leads to only slight performance loss compared with the optimal policy.