QoS-aware resource allocation for multicast service over vehicular networks

Quality of service (QoS) constrained multicast service over vehicular networks has considerable benefit for both road safety and entertainment, while the resource allocation problem of it is challenging due to the high mobility of vehicles. In this paper, we manage the vehicle mobility by dividing one scheduling round into multiple segments, and investigate the resource allocation problem to answer the questions of which modulation and coding scheme (MCS) should be adopted for each flow in each segment, and how to schedule the radio resources among all the flows. We consider two kinds of multicast services. For the multicast service to cover all the recipients, we formulate the problem as a resource scheduling problem with fixed MCS profile, and propose a k-commodity packing based approximation algorithm to solve it with low complexity. For the multicast service with adaptive recipients, we notice that the number of valid MCS profiles for each flow is limited, and propose a heuristic algorithm to search for proper MCS profile assignments. The simulation results verify the efficiency of the proposed scheme.