Coverage study of dense device-to-device communications underlaying cellular networks

Device-to-Device (D2D) communication operating as an underlay to the cellular network has been lately exploited to facilitate proximity-aware services and data traffic offloading. While D2D communication has great potentials to improve wireless network spectral efficiency and energy efficiency due to the proximity of communication parties and a higher spectrum reuse gain, how to guarantee the coverage and capacity for both cellular users and D2D users when dense D2D communications are carried underlay cellar networks still remains as a big challenge. This paper provides the coverage study by deriving the uplink and downlink SINR distributions for both cellular users and dense D2D users based on statistical user distribution and channel information. We model the spacial distribution of the D2D pairs as a homogeneous Poisson Point Process (PPP) and D2D users can either use cellular uplink resources or downlink resources. The simulation results match closely with the analytical studies. The analytical tools can be conveniently extended to evaluate other key D2D wireless network performance metrics including network capacity and outage probability, and provide great insights on the critical network design issues such as power control, interference management, and resource allocations.