Vickrey Auction-Based Secondary Relay Selection in Cognitive Hybrid Satellite-Terrestrial Overlay Networks With Non-Orthogonal Multiple Access

In this letter, we investigate the Vickrey auction-based secondary relay selection in cognitive hybrid satellite-terrestrial overlay networks (CHSTONs) with non-orthogonal multiple access (NOMA). We analyze a cooperative spectrum sharing scheme for a multi-potential secondary relay selection scenario, in which the Vickrey auction is introduced to achieve an efficient secondary relay selection by one shot within the distributed computation. Both the decode-and-forward (DF) and amplify-and-forward (AF) protocols are considered for the relay to retransmit the primary user's message, separately. Besides, the NOMA scheme is implemented to increase the total capacity in the second temporal phase. Finally, simulation results validate that the proposed auction-based approach is more effective than conventional approaches in secondary relay selection. Also, the influence of key factors on the performance of the auction mechanism is analyzed by the simulations.