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.

翻译：大多数速率分割多址接入（RSMA）的实现依赖接收端的连续干扰消除（SIC），其性能天然受限于公共流解码过程中的错误传播。本文通过开发基于联合解映射（JD）的免SIC RSMA接收机来解决该问题，该接收机直接在复合星座上对比特向量进行判决。借助两用户多输入单输出（MISO）原型系统，我们开展空中测量以系统对比基于SIC与JD的接收机。实验结果表明，所提出的免SIC接收机在更广工作范围内具有更强的可靠性与更优的实用性，所有观测结果均与理论预期一致。