Cooperation via Spectrum Sharing for Physical Layer Security in Device-to-Device Communications Underlaying Cellular Networks

Abstract

In this paper, we investigate the cooperation issue via spectrum sharing when employing the physical layer security concept into the Device-to-Device (D2D) communications underlaying cellular network. Different from previously related works, we consider a more general interference case that multiple D2D pairs can access the same resource block (RB) and one D2D pair is also permitted to access multiple RBs, and provide a novel cooperation mechanism in the investigated D2D communications underlaying cellular network. Furthermore, we formulate the provided cooperation mechanism among cellular communication links and D2D pairs as a coalitional game. Then, based on a newly defined Max-Coalition order in the constructed game, we further propose a merge-and-split based coalition formation algorithm for cellular communication links and D2D pairs to achieve efficient and effective cooperation, leading to both improved system secrecy rate and social welfare. Simulation results indicate the efficiency of the designed cooperation mechanism and the proposed merge-and-split based coalition formation algorithm.