Blockchain Empowered Dynamic Spectrum Sharing: Standards, State of Research and Road Ahead

As the scarcity of spectrum resources especially in mid-band becomes more significant in beyond 5G and 6G era, spectrum sharing is promising to solve this problem. Various spectrum sharing approaches have been proposed and standardized such as geolocation database. However, these approaches are centralized and face some challenges such as scalability and high computational intensity. The emergence of blockchain technology provides a great solution to enhance spectrum sharing technology in a decentralized way. With blockchain technology, trust can be established among multiple public or private wireless networks owned by different operators. Moreover, decentralized ledgers can reduce the amount of transactions and validation process executed by each node. Therefore, spectrum trading efficiency is improved and transaction processing latency is reduced. In this paper, the standardization progress of spectrum sharing and blockchain application in wireless communications are summarized. Then, the key issues encountered by blockchain based spectrum sharing are investigated and potential solutions are proposed. Finally, The future research directions for blockchain based dynamic spectrum sharing are presented.