Contention-based Uplink Small Data Transmission for mMTC in 5G

In the research of 5th Generation (5G) Cellular networks, contention-based transmission (CBT) returns to sight due to its possibility of low latency and smaller signaling overhead when the collision rate is low. Based on our previous study, available collision and overload mechanisms may not be enough to solve the collision challenge faced by the CBT for small data transmission in the massive Machine-Type Communication (mMTC) scenario. In order to efficiently transmit small data in the discussed scenario, we provide system design in this paper, including transmission procedure, resource allocation algorithm and feedback design. We also propose a systematic evaluation method for CBT with proper traffic model and metrics definition. Simulation results show that the proposed resource allocation algorithm outperforms relevant existing approaches under various metrics.