Joint Access Control and Resource Allocation for mMTC based on Tagged Preamble

In this paper, we investigate the access control and resource allocation for mMTC based on tagged preamble (PA). Through two detection of tagged PA at base station, MTC device can be further distinguished in RA process. Then, optimization problem concerning joint access class barring parameter and tag number for each area is formulated, which aims as maximizing the throughput of the cell. To solve this optimization problem, we decompose the original problem and deal with it in two steps, first we can obtain a closed expression of the optimal ACB parameters for each area. In the second step, we propose a “class waterfilling” algorithm to optimize the number of tags in each area. Simulation results show that dynamic tag allocation and ACB factor adjustment can increase the access success probability of the random access process and reduce the average access delay.