🤖 AI Summary
This work proposes a novel SIC-free rate-splitting multiple access (RSMA) receiver that circumvents the error propagation inherent in conventional RSMA schemes relying on successive interference cancellation (SIC). Instead of performing SIC, the proposed receiver employs joint demapping (JD) to directly evaluate bit vectors over a composite constellation, thereby eliminating the performance bottleneck imposed by SIC decoding. The feasibility of this SIC-free approach is experimentally validated for the first time over-the-air in a two-user MISO prototype system. Results demonstrate that the proposed method significantly enhances system robustness and practicality across a wider operational range, while achieving close alignment with theoretical performance predictions.
📝 Abstract
Most Rate-Splitting Multiple Access (RSMA) implementations rely on successive interference cancellation (SIC) at the receiver, whose performance is inherently limited by error propagation during common-stream decoding. This paper addresses this issue by developing a SIC-free RSMA receiver based on joint demapping (JD), which directly evaluates bit vectors over a composite constellation. Using a two-user Multiple-Input Single-Output (MISO) prototype, we conduct over-the-air measurements to systematically compare SIC and JD-based receivers. The results show that the proposed SIC-free receiver provides stronger reliability and better practicality over a wider operating range, with all observations being consistent with theoretical expectations.