Coalition Formation Approaches for Cooperative Networks with SWIPT

This paper proposes three game-theoretic approaches for coalition formation in cooperative networks with simultaneous wireless information and power transfer. To improve the reception reliability of destinations with poor channel conditions, we first divide destinations in the network into two types: Type I and Type II. Type I destinations refer to the destinations with capability of successful information decoding and energy harvesting, which serve as relays to help other destinations. Type II destinations have poor connections to the source and hence compete to obtain help from Type I destinations. Accordingly, cooperative relaying strategies for the two types of destinations are proposed on the basis of coalition formation game. First, we propose to utilize the dynamic programming (DP) approach to obtain the optimal coalition structure in the network, though at the cost of heavy time and storage complexity. Then, two distributed hedonic coalition formation (DHCF) approaches are developed to generate coalition structures, which are more efficient than the DP approach. Simulation results show that all proposed approaches outperform the non-cooperative one (i.e., direct link transmission). The results also illustrate that the DP approach achieves the largest data rate and lowest outage probability for destinations, and the DHCF approaches achieve near-to-optimal performance.