Design Of Hybrid Spectrum Auction Access Model Based On Blockchain

The contradiction between the increase of wireless terminal equipment and the insufficient utilization of spectrum makes the problem of spectrum shortage more and more serious.The proposal of dynamic spectrum access technology provides a new idea for solving this problem.To motivate the primary users(PUs)in the dynamic spectrum access model to participate in spectrum sharing,this thesis introduces an auction mechanism so that the PUs who participate in spectrum sharing can obtain benefits.To resist the single-node attack in the auction model and protect the transaction security between the PU and the secondary user(SU),blockchain technology is applied to the spectrum auction mechanism.To stimulate PUs to participate in spectrum sharing and further improve spectrum utilization,a hybrid spectrum auction access scheme that allows PUs to auction the spectrum they are using is proposed.In this scheme,the channel state of the PU is modeled as a 2-state Markov model,and the SU selects the required spectrum according to the channel state of the PU.To ensure spectrum reuse and the transmission of the PU is not interfered,the hybrid scheme uses the interference model to model the interference of the SUs,and calculates the interference of the SU to ensure the successful transmission of the PU and the SU.In addition,three economic attributes need to be satisfied when designing the spectrum auction mechanism,namely individual rationality,truthness and nonnegativity.To meet the economic properties of auction,the hybrid scheme designs spectrum auction mechanism from three aspects: buyer grouping,winner decision and price clearing.Simulations show that the hybrid spectrum auction access scheme can ensure better spectrum reuse while satisfying the economic properties of auctions.In the traditional auction mechanism,sellers and buyers need to submit bids to the auctioneer,and the auctioneer will implement the spectrum auction,which may make the system more prone to collapse when subjected to a single-node attack.To ensure that the system can resist single-node attacks and protect spectrum transactions between users,this thesis designs a blockchain-based spectrum auction access model.In this model,all users in the network jointly participate in the implementation of the auction mechanism,and the security of data transmission is ensured through asymmetric encryption.To ensure the fairness of the system and reduce the energy consumption of generating blcoks,this thesis designs a consensus mechanism based on priority,which selects the leader node according to the user’s priority to update the blockchain and obtain rewards.The simulation results show that the model can guarantee the energy efficiency and fairness of the system.