A Guard Zone Based Scalable Mode Selection Scheme in D2D Underlaid Cellular Networks

With the emergence of new applications, e.g., video gaming, file sharing and proximity aware social networks, high data-rate traffics will be likely to occur between devices in the vicinity of each other. Enabling Device to Device (D2D) communication between such devices can efficiently offload these traffics from the base station. Meanwhile, by reusing the cellular spectrum, D2D has the potential to significantly improve the spectral efficiency. However, if not controlled carefully, the interference caused by D2D communication may severely degrade the performance of regular cellular services. To resolve this issue, this paper proposes a simple guard-zone based mode selection scheme as an efficient and scalable mechanism to manage the interference in D2D underlaid cellular systems. With the help of stochastic geometry, we rigorously analyze the interference and throughput of such system. The results indicate the existence of an optimal guard zone radius that maximizes the total system throughput. Thanks to the tractability of our analysis, the optimal guard zone radius can be efficiently obtained. Through extensive numerical analysis, we show that the success probability and aggregate throughput obtained at the optimal guard zone radius are significantly greater than those without guard zone.