Cross-Tier Coordination in Spectrum Sharing: A Blockchain Approach

To solve the contradiction between the increasing spectrum demand of wireless services and the finite and underutilized spectrum resources, the concept of spectrum sharing was proposed to allow unlicensed secondary users to temporarily share unused spectrum of licensed primary users. Currently, approaches based on geolocation databases have been standard-ized and commercialized, such as TV white space, license shared access (LSA) and the citizen broadband radio services (CBRS). These are centralized schemes where all spectrum allocation decisions are made by a third party or a cloud-based spectrum manager. Recently, blockchain technology has drawn the attention of researchers for its characteristics, such as decentralization, transparency, privacy preservation, and immutability. In this paper, we propose a blockchain-based spectrum sharing scheme to enable the direct coordination of the interference budget between priority users and general access users in the CBRS network. Evaluation results show that our proposed approach can increase the total number of users that can access the shared spectrum.