Spectrum Management In Cognitive Radio Based Smart Grid Neighborhood Area Network

Smart grid integrates advanced communication and control technology to improve the interaction with users, enhance the security of grid, avoid the waste of electric energy.Reliable and real-time communication in smart grid is an important factor to ensure the efficiency, safety and reliablity. The communication system in smart grid can be logically divided into three layers, this thesis focuses on the application of cognitive radio technology in the neighbor area network.The dynamic demand response is an effective solution to shift the peak of user load in the smart grid, and there has been extensive researches at home and abroad about it.The fast convergence algorithm of real-time price in dynamic demand response is studied in this thesis. Also, the influence that communication realibility caused to dynamic demand response in the neighbor area network is discussed. With the development of smart grid, there has been more and more smart meters, measuring equipments,monitoring equipments, and all of these increased the amount of data, which requires the extra authorized spectrum. So, this thesis considered the effective use of cognitive radio technology in the smart grid neighbor area network.This thesis studied the optimization problem about spectrum sensing in the cognitive radio based smart grid neighbor area network. The packet loss rate and delay of cognitive radio based communication are considered. Also, the relationship between spectrum sensing and dynamic demand response is studied. The existence and uniqueness of the optimal sensing time to get the minimum communication delay is proved in this thesis.In addition, the optimal sensing time to balance spectrum sensing overhead and the influence communication unrealibility caused to dynamic demand response is found.There are many services in smart grid, such as data acquisition, video surveillance,dynamic demand response and emergency communication, and different service has different requirement of the communication quality. Spectrum sharing technology with regard to requirement of the communication quality is discussed in the cognitive radio based smart grid neighbor area network. Both spectrum selection algorithm based on the type of service data and spectrum allocation algorithm based on the priority of service terminal are proposed in the end.In this thesis, the influence that communication reliability caused to dynamic demand response is examined and the relationship between spectrum sensing time and communication delay is verified through simulation. Also, the optimal sensing time to balance the sensing overhead and dynamic demand response is verified. In the end,different kind of channel selection algorithms are compared through performance simulation, the result of which indicates that the proposed algorithm is better. Numeric simulation verified the correctness and effectiveness of the proposed static game algorithm and dynamic spectrum game algorithm based on the priority of service terminal.