Hybrid Spectrum Access in Cognitive-Radio-Based Smart-Grid Communications Systems

Cognitive-radio-based smart-grid networks have been studied recently as an efficient and reliable communications infrastructure for the future power grid. In this paper, we consider the spectrum resource management in cognitive-radio-based smart-grid networks. A new spectrum access paradigm called hybrid spectrum access (HSA) is proposed, in which both licensed and unlicensed spectrum bands are intelligently scheduled for the transmission of smart-grid services. The admission control problem under HSA is deliberately investigated. Furthermore, the impact of spectrum sensing error on the performance of HSA is analyzed by using a multidimensional Markov chain. Regarding the practical applications of the smart grid, two optimization problems, namely, cost-driven spectrum leasing and quality of service (QoS)-driven spectrum management, are formulated. Numeric results indicate that the HSA strategy is able to significantly improve the QoS of the smart-grid services, save the cost in spectrum leasing, and maintain the system interference at a sufficiently low range.