Investigation on resource scheduling with coexistence of unicast and multicast services in LTE OFDMA system

Multicasting is an effective method of transmitting the group messages that results in minimal utilization of network resources. But in real scenario, both unicast and multicast services are to be served by the evolved Node B (eNB). So an appropriate resource allocation method should be adopted to satisfy the Quality of Service (QoS) requirements of these services. This paper focuses on resource allocation method for Long Term Evolution (LTE) downlink when these services are scheduled by the eNB. To improve the system throughput, an objective function is formulated that maximizes the throughput of both unicast and multicast services. The multicast group is in turn divided into subgroups and the subgrouping allocation is carried out by means of Genetic Algorithm (GA) that aims to maximize the total throughput. It is shown that multicast with subgrouping shows 20% increase in the total throughput and 3% reduction in average delay when compared with combined unicast and conventional multicasting method that uses Least Channel Gain (LCG) user rate for multicast transmission.