RIS-Aided E2E Multi-Path Uplink Transmission Optimization for 6G Time-Sensitive Services

TL;DR

This paper introduces a RIS-assisted multi-path uplink transmission scheme for 6G that optimizes latency by jointly designing traffic splitting, power, combining, and RIS phases, significantly reducing end-to-end latency.

Contribution

It proposes a novel RIS-aided E2E multi-path uplink architecture with an optimization framework to minimize latency, explicitly considering radio and backhaul delays.

Findings

Reduces average E2E latency by up to 43% for a single user.

Achieves up to 32% latency reduction system-wide.

Demonstrates effectiveness through simulation comparisons.

Abstract

The Access Traffic Steering, Switching, and Splitting (ATSSS) defined in the latest 3GPP Release 19 enables traffic flow over the multiple access paths to achieve the lower-latency End-to-end (E2E) delivery for 6G time-sensitive services. However, the existing E2E multi-path operation often falls short of more stringent QoS requirements for 6G time-sensitive services. This work proposes a Reconfigurable Intelligent Surfaces (RIS)-aided E2E multi-path uplink (UL) transmission architecture that explicitly accounts for both radio link latency and N3 backhaul latency, via the coupled designs of the UL traffic-splitting ratio, transmit power, receive combining, and RIS phase shift under practical constraints to achieve the minimum average E2E latency. We develop an alternating optimization framework that updates the above target parameters to be optimized. The simulations were conducted to compare the effectiveness of the proposed E2E optimization framework that lowers the average E2E latency up to 43% for a single user and 32% for the whole system compared with baselines in our prior work [1].