Optimization algorithms for massive accesses of MTC devices in LTE-A networks

The massive random accesses of machine type communication (MTC) in current wireless networks (e.g. LTE-A, WiMAX) are a challenging and urgent issue. In this paper, the random access performances in LTE-A networks are first analyzed in terms of success probability, access delay, physical random access channel efficiency, and the number of retransmissions. Based on the analysis, two QoS-based optimization algorithms are then proposed for the random access of massive MTC devices. Simulation results show that the proposed algorithms achieve better performances than non-optimized random access, providing required QoS guarantees for each MTC application, and meanwhile optimizing the spectrum efficiency and energy efficiency.