Chung-Ming Huang

In a platoon communication scenario, the Platoon Leader (PL) vehicle interacts with the gNodeB (gNB) to obtain some assigned radio resources and then the obtained radio resources are allocated to the PL vehicle and its Platoon Member (PM) vehicles. The high transmission delay in the platoon network affects the quality of vehicles’ connectivity. Therefore, the issues of improving radio resource’s spectral efficiency and stability of the vehicle platooning with limited radio resources need to be tackled. This work proposes the 2-STage Resource Allocation (2-STRA) method for multi-platoon communication to reduce the transmission latency of platoon vehicles, i.e., it can improve the data transmission rates of platoon vehicles for the conditions of various speeds and various numbers of subchannels. In the 1 ^st stage, a greedy algorithm that jointly considers subchannel allocation and power control for PL vehicles’ resource allocation is devised. In the 2 ^nd stage, the resource allocation for PM vehicles, which is based on the subchannels that are not allocated to PL vehicles, is resolved. A tripartite hypergraph, in which a tripartite hyperedge links (i) a cluster of PM vehicles that use the same subchannel, (ii) an individual cellular user and (iii) a subchannel, is adopted to devise the PM vehicles’ resource allocation algorithm. The simulation results show that the proposed 2-STRA method can have better performance in terms of spectral efficiency and the sum of data transmission rate comparing with the other methods.

The traditional, small cell data offloading for a vehicle can be enabled when the vehicle is inside the corresponding small cell's signal range. Through utilizing the sidelink communication technique of the cellular vehicle-to-vehicle (C-V2V) and the Multi-access Edge Computing (MEC) architecture, this paper proposes a new small cell data offloading's scenario that can enable small cell data offloading when vehicles are still outside the signal range of the small cell. The proposed method is called Small Cell Offloading Before Entering into the small cell's Signal Range (SCO-BESR). Using the proposed SCO-BESR method, a vehicle X that connects with the macro cell and is not inside the signal range of small cell Z can connect with a vehicle Y inside the signal range of small cell Z using a C-V2V sidelink to have the small cell data offloading through the SCO-BESR path "X-Y-Z cell" until X enters into the signal range of small cell Z. Let each vehicle periodically report its context to the MEC server. Then, the MEC server can periodically perform the matching process between those vehicles that are inside and outside small cell's signal range to establish multiple SCO-BESR paths for multiple vehicles outside the signal range to have the SCO-BESR using the proposed greedy algorithm. The performance evaluation results shown that the proposed SCO-BESR method is better than the traditional small cell data offloading method that can only be enabled when a vehicle is inside the signal range of the corresponding small cell.