Fig. 1From: Open sub-granting radio resources in overlay D2D-based V2V communicationsA typical network is consisting of one eNB, one D2D-UE, and one D2I-UE. The \(k-th\) D2D user sub-grants the un-used radio resources to the \(m-th\) D2I user, when channel gain \(G_{km}\) between \(k-th\) D2D user and \(m-th\) D2I user is above a certain thresholdBack to article page