Access Performance Improvement in D2D Aided Underlaying Cellular Networks

Device-to-device (D2D) communication has been a significant supplement for traditional cellular network (CN) when meeting with the increasing number of requiring users. In this paper, we assume that cellular user equipments (CUEs) has priority over D2D user equipments (DUEs) on utilizing spectrum resource, and we aim at maximizing the average number of successfully corresponding DUEs. The spatial distribution of requiring users is assumed as homogeneous Poisson Point Process (PPP), therefore it is analytically tractable to derive the expression of D2D communication coverage probability. We derive the approximate closed-form expression of successfully corresponding DUEs' average number, and then obtain the optimal point of the expression with respect to activated DUE's density, and finally verify the effectiveness of this optimal point by numerical results.