Fuzzy logic power control of device to device communication underlay TD-LTE-A system

When the D2D communication technology is introduced into the cellular system, especially when the D2D UEs multiplex the non-orthogonal spectrum resources of cellular UEs, the transmit power of D2D UEs and cellular UEs must be strictly controlled to reduce the interference between two kinds of UEs and benefit from D2D communication mode. In this paper, the mathematical model of power control of D2D communication underlay LTE-A system is established, and the power control principles in this scenario are achieved. Based on the principles, a continuous fuzzy power control scheme for D2D communication UEs is designed to achieve better communication quality for D2D UEs, while the cellular UEs can communicate normally in low transmit power. The simulation results reveal that the continuous fuzzy power control scheme can improve the D2D UEs' average SINR and achieve lower LTE UEs' outage probability with more rapid convergence than fixed-step power control scheme.