Resource Allocation in a New Random Access for M2M Communications

In order to increase the number of successful accesses for machine-to-machine (M2M) communication, we propose a new random access (RA) procedure. The proposed RA procedure allows evolved NodeB (eNB) to know the preamble collisions in the first step by attaching user equipment (UE) identity information in physical random access channel (PRACH). This improvement prevents eNB from scheduling physical uplink shared channel (PUSCH) to the collided preambles, which improves the resource efficiency. Based on the enhanced RA procedure, a resource allocation scheme is proposed. By estimating the number of successful preamble, the proposed scheme achieves a reasonable resource tradeoff between PRACH and PUSCH. Simulation results show that the proposed RA procedure significantly improves the number of successful accesses as well as the resource efficiency.