Geometrical-Based Throughput Analysis of Device-to-Device Communications in a Sector-Partitioned Cell

Device-to-device (D2D) communications in cellular networks are considered a promising technology for improving network throughput, spectrum efficiency, and transmission delay. In this paper, the Power Emission Density (PED)-based interference modeling method is applied to explore proper network settings for enabling multiple concurrent D2D pairs in a sector-partitioned cell. With the constraint of the Signal-to-Interference Ratio (SIR) requirements for both the macro-cell and D2D communications, an exclusive region-based analytical model is proposed to obtain the guard distances from a D2D user to the base station, to the transmitting cellular user, and to other communicating D2D pairs, respectively, when the uplink resource is reused. With these guard distances, the bounds of the maximum throughput improvement provided by D2D communications are then derived for different sector-based resource allocation schemes. Extensive simulations are conducted to verify our analytical results. The new results obtained in this work can provide useful guidelines for the deployment of future cellular networks with underlaying D2D communications.