Latency Aware Multi-Path Data Transmission for URLLC Services

5th Generation Mobile Communication Technology (5G) utilizes Access Traffic Steering, Switching, and Splitting (ATSSS) rule to enable multi-path data transmission, which is currently being standardized. Recently, the 3rd Generation Partnership Project (3GPP) SA1 and SA2 have been working on multi-path solution for possible improvement from different perspectives. However, the existing 3GPP multi-path solution has some limitations on URLLC traffic in terms of reliability and latency requirements. In order to capture the potential gains of multi-path architecture in the context of URLLC services, this paper proposes a new traffic splitting technique which can more efficiently enjoy the benefit of multi-path architecture in reducing users' uplink (UL) End-to-End (E2E) latency. In particular, we formulate an optimization framework which minimizes the UL E2E latency of users via optimizing the ratio of traffic assigned to each path and corresponding transmit power. The performance of the proposed scheme is evaluated via well designed simulations.