Effective Uplink Data Transmission Scheme for MTCDs in LTE-A Networks

With the demand of uplink data generated by massive machine type communication devices (MTCDs) in LTE-A networks, the traditional radio access and resource allocation schemes are not suitable for IoT applications. Because, comparing to traditional human type communications, the machine type devices need much more access frequency but with much smaller data volume each time. In this paper, we propose the novel random access scheme for MTCDs together with piggyback small data in Msg3 of the random access procedure to improve the uplink data transmission performance. The implicit preamble reservation concept is applied to prevent dense random access so as to increase the access success ratio. The contention-free preambles together with small data are supported for the devices which definitely have data to transmit. Two approaches, Limited Buffer Threshold Algorithm (LBTA) and Limited SCH Capacity Algorithm (LSCA) are proposed and their performance are compared. The simulation results show that the proposed schemes illustrate good performance in transmission delay and effective preamble utilization.