A Two-phase Transmission Protocol Design for Ultra-reliable Communications

The emergence of the fifth generation (5G) wireless communications promotes the development of machine-type communication (MTC), which emphasizes on the ultra-reliable and low latency communications. In order to meet such requirements and considering the hierarchical network architecture in industrial scene, in this paper, we propose a novel two-phase transmission protocol based on the clustered device-to-device (D2D) networks, so that in industrial automation, the downlink transmissions of control information could reach the reliability as high as possible within 1ms. Employing the diversity gain through multi-user beam forming in Phase I and the time-division multiple-access (TDMA) fashion in Phase II, both the power consumption and reliability metrics are targeted. Simulation results show that the proposed transmission protocol realizes the ultra-reliable communications within the delay requirement, and advances comparing with the existing schemes to some extent.