Distributed Mode and Power Selection for Non-Orthogonal D2D Communications: A Stochastic Approach

The coexistence of device-to-device (D2D) and cellular communications in the same band is a promising solution to the dramatic increase of wireless networks traffic load, in particular in the presence of local traffic, when source and destination nodes are in close proximity. In this case, the mobile nodes can communicate in a semi-autonomous way (D2D mode), with minimal or no control by the base station (BS), but they may create a harmful interference to the cellular communications. In order to avoid it, we design a distributed approach that allows the mobile node to acquire in real time local information by observing few channel and topology parameters. Based on this information, each user can infer in advance not only the quality of its transmission, but also its impact on other ongoing surrounding communications toward the BS. This enables a smart, adaptive mode, and power selection performed with a network wide perspective. Differently from most approaches, this selection is made autonomously by each D2D sources, with no need for a centralized scheduling. We compare our strategy to the state-of-the-art in the same distributed network scenario, showing the importance of exploiting local information for a dynamic, interference aware power, and mode selection.