Dynamic Bargaining for Relay-Based Cooperative Spectrum Sharing

Cooperative spectrum sharing can effectively improve the spectrum usage by allowing secondary users (SUs) to dynamically and opportunistically share the licensed bands with primary users (PUs). In return, an SU will relay a PU's traffic to improve the PU's effective data rate. In this paper, we study how one PU and one SU achieve an efficient spectrum sharing through dynamic noncooperative bargaining. The key challenge is that the PU does not have complete information of the SU's energy cost. We model the dynamic bargaining with incomplete information as a dynamic Bayesian game, and investigate the equilibria under both single-slot and multi-slot bargaining models. Theoretical analysis and numerical results indicate that our proposed scheme can lead to a win-win situation, where both the PU and the SU obtain data rate improvements via the bargaining-based CSS mechanism. Furthermore, the SU can take advantage of the incomplete information to improve its bargaining power (also called reputation effect), and thus gain a higher data rate.