A Multi-queue Aggregation Framework for M2M Traffic in LTE-A and Beyond Networks

Abstract

Traffic aggregation has been considered as an effective approach to improve the radio resource utilization for M2M communication in LTE-A and beyond networks. In the LTE-A specification, the Relay Node (RN) is recommended to aggregate uplink M2M small-sized packets. However, the delay brought by the packets aggregation is inevitably increased, which is a vital metric for M2M packets with low delay requirement, such as emergency alerting. In this paper, we propose a new framework for optimal aggregation implemented in the PDCP of RN, which features balancing a tradeoff between QoS requirements of packets and the utilization efficiency of Physical Radio Blocks (PRBs). Specifically, (1) the RN dispatches the new arrival M2M packets into corresponding virtual queues according to their priorities set by M2M devices. Then, an Optimal Aggregating Scheme (OAS) is designed to minimize the PRB usage in condition satisfying the specific restriction of waiting time of packets in virtual queues. (2) The optimal aggregating problem is proved to be a NP-hard problem, which is solved by the Priority Branch and Bound Algorithm (PBBA) and the Priority Aggregating Heuristic. Numerical results illustrate that OAS achieves a tradeoff of QoS and PRB utilization efficiency in comparison with four existing schemes.