Sensing-Mining-Access Tradeoff in Blockchain-Enabled Dynamic Spectrum Access

Dynamic spectrum access (DSA) is crucial to improve the utilization efficiency of the limited and precious radio spectrum resources. Recently, the application of blockchain is proposed to improve the security, distribution and transparency of DSA. However, in opportunistic spectrum access (OSA), the implementation of blockchain consumes considerable amount time in each time slot so that the time left for spectrum sensing and access will be decreased. Therefore, in this letter, we aim to optimize the frame structure regarding the sensing time and mining time so that the average achievable throughput is maximized. We first decouple the original optimization problem into two sub-optimization problems with respect to sensing time and mining time, respectively, and then prove that there exists a unique maximum point for both the two sub-optimization problems. After that, an alternating algorithm is proposed for the optimization. Using the simulations, the sensing-mining-access tradeoff and effectiveness of our proposed algorithm to optimize such a tradeoff are illustrated.