In this paper, we explore an efficient uncoupled unsourced random access (UURA) scheme for 6G massive communication. UURA is a typical framework of unsourced random access that addresses the problems of codeword detection and message stitching, without the use of check bits. Firstly, we establish a framework for UURA, allowing for immediate decoding of sub-messages upon arrival. Thus, the processing delay is effectively reduced due to the decreasing waiting time. Next, we propose an integrated decoding algorithm for sub-messages by leveraging matrix information geometry (MIG) theory. Specifically, MIG is applied to measure the feature similarities of codewords belonging to the same user equipment, and thus sub-message can be stitched once it is received. This enables the timely recovery of a portion of the original message by simultaneously detecting and stitching codewords within the current sub-slot. Furthermore, we analyze the performance of the proposed integrated decoding-based UURA scheme in terms of computational complexity and convergence rate. Finally, we present extensive simulation results to validate the effectiveness of the proposed scheme in 6G wireless networks.

翻译：本文针对6G大规模通信场景，探索了一种高效的非耦合无源随机接入（UURA）方案。URA作为一种典型无源随机接入框架，可在无需校验比特的情况下解决码字检测与消息拼接问题。首先，我们构建了UURA框架，支持子消息到达即译码，从而通过减少等待时间有效降低处理时延。其次，基于矩阵信息几何（MIG）理论，提出子消息联合译码算法：具体利用MIG量测属于同一用户设备的码字特征相似度，实现子消息接收即拼接。该方法通过在当前子时隙内同步完成码字检测与拼接，可及时恢复部分原始消息。此外，我们从计算复杂度和收敛速率两个维度分析了所提联合译码UURA方案的性能。最后，通过大量仿真实验验证了该方案在6G无线网络中的有效性。