Ultra-Reliable and Low-Latency Communications: Prediction and Communication Co-Design

Abstract

Ultra-reliable and low-latency communications (URLLC) are considered as one of three key application scenarios in the 5th generation (5G) communication systems. It is very challenging to satisfy the ultra-low end-to-end (E2E) delay requirement, especially in long distance communication scenarios since the delay in backhauls and core networks could be tens of milliseconds. In this work, we aim to reduce the latency experienced by users through prediction and communication co-design, where the transmitter predicts it's future states and sends them to the receiver in advance. Considering that the prediction is not error free, we take into consideration prediction errors and the packet loss in communications when analyzing the reliability of the system. Then, we formulate an optimization problem that minimizes the required bandwidth to satisfy the E2E delay and reliability requirements of URLLC. With the proposed method, it is possible for users to achieve zero latency experience when the prediction time equals to the communication delay. Simulation results verify the effectiveness of the proposed method, and show that the tradeoffs among bandwidth, reliability, and latency can be fundamentally improved via prediction and communication co-design. The results are further evaluated by using practical motion data acquired from experiments of a real hardware device.