Resource Allocation in Relay-Assisted Mission-Critical Industrial Internet of Things

As one of the main scenarios of 5G, Ultra Reliable Low Latency Communication (URLLC) plays an important role in Industrial Internet of Things (IIoT) for smart factories. At present, most researches on URLLC use Shannon capacity for infinite blocklength, which is not suitable for short packet transmission adopted by URLLC. In this paper, we consider the resource allocation of mission-critical service in the smart factory, where IIoT devices receive the control information from both base station (BS) and relay. The purpose of this paper is to jointly optimize the power allocation, the position of relay, and the blocklength with finite blocklength information theory to minimize the decoding error rate of the device. This paper proposes a low-complexity algorithm that effectively solves this optimization problem. Simulation results show that relay- assisted transmission and optimized resource allocation can significantly reduce the error rate.