DSCA: Dynamic Spectrum Co-Access Between the Primary Users and the Secondary Users

In the current architecture of dynamic spectrum access, secondary users (SUs) only opportunistically access the spectrum of primary users (PUs). The resurgence of PUs disrupts secondary communications, which can result in poor performance for SUs. In this paper, we propose a novel architecture for dynamic spectrum access, termed dynamic spectrum co-access (DSCA), to enable the PU and the SU to simultaneously access the licensed spectrum. With DSCA, SUs transparently incentivize PUs through increasing the PU performance so that SUs can access the spectrum simultaneously with PUs; hence, there is no disruption to secondary communications due to the resurgence of PUs. We derive a mathematical model to formulate the minimum incentives for the spectrum co-access between the PU and the SU and to compute the region of co-access to determine the SUs that can co-access with a given PU. An algorithm is also developed to select the co-access primary and secondary links to maximize network performance. Numerical results indicate that DSCA significantly improves performance compared with the current architecture of dynamic spectrum access.