Selective Overlay Mode Operation for D2D Communication in Dense 5G Cellular Networks

Fifth generation (5G) cellular networks would include millimeter wave (mmWave) for communication which gains the advantage of extensive frequency reuse and directive propagation. The recent trends in device-to-device (D2D) communication have escalated the importance of proximity based services for next generation cellular systems. The integration of mmWave and D2D technology will improve the performance and spectral efficiency greatly. In areas with high call traffic density, D2D communication can operate in overlay mode giving the advantage of low complexity interference avoidance technique. The complexity is decreased as the resources to overlay mode are dedicated resulting in no interference from cellular user unlike in underlay mode. Such a scenario is considered in this paper where interference management between D2D devices sharing same radio resources plays a key role in system performance. Thus, the inband resources for D2D operation selectively switch to overlay mode in based on the call traffic. Two problems are addressed in this paper. Firstly, assigning the resources for overlay mode which is solved using quadratic programming. Next, the problem is formulated to maximize system capacity in overlay mode which is solved using a heuristic algorithm which is simulated. The proposed scheme has optimal performance for dense network in controlled overlay operation for 5G networks. The scheme also overcomes the problem of spectrum wastage in overlay mode by its selective operation.