Time-frequency spectrum leasing for OFDM-based Dynamic Spectrum Sharing systems

In cognitive radio systems, Dynamic Spectrum Leasing (DSL) can improve the efficiency of spectrum utilization. In DSL, the primary user who has the license for a part of the bandwidth, decides to lease it to a secondary user or not. In this paper, we assume an OFDM-based system and perform the leasing operation in this system where the primary user leases the spectrum for a number of OFDM symbols to secondary users in exchange of a better quality-of-service achieved by secondary network cooperation. The secondary users use a part of the spectrum for relaying the primary data to the primary receiver and the rest of the spectrum for their own transmissions. More precisely, we propose a time-frequency domain leasing scheme. Simulation results show that both primary and secondary users benefit from this proposed spectrum sharing strategy.