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, the authors 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.