Spectrum leasing based on bandwidth efficient relaying in cognitive radio networks

A spectrum leasing scheme is proposed for overlaid wireless networks based on the spectral efficient relaying. The potential secondary transmitters compete to assist the primary transmission using the one-path alternate or two-path successive relaying in exchange for the opportunity of spectrum access. The cognitive relaying mode is dynamically chosen based on the availability of secondary receiver for the cooperation. The secondary user that can support the primary transmission and has the highest secondary rate is selected as the best to join the spectrum leasing. The rate and outage performance of both systems are studied. Numerical results show that the primary performance is greatly improved compared with direct transmission, and the secondary requirement is also well satisfied.