The next generation of wireless communication technology is anticipated to address the communication reliability challenges encountered in high-speed mobile communication scenarios. An Orthogonal Time Frequency Space (OTFS) system has been introduced as a solution that effectively mitigates these issues. However, OTFS is associated with relatively high pilot overhead and multiuser multiplexing overhead. In response to these concerns within the OTFS framework, a novel modulation technology known as Affine Frequency Division Multiplexing (AFDM) which is based on the discrete affine Fourier transform has emerged. AFDM effectively resolves the challenges by achieving full diversity through parameter adjustments aligned with the channel's delay-Doppler profile. Consequently, AFDM is capable of achieving performance levels comparable to OTFS. As the research on AFDM detection is currently limited, we present a low-complexity yet efficient message passing (MP) algorithm. This algorithm handles joint interference cancellation and detection while capitalizing on the inherent sparsity of the channel. Based on simulation results, the MP detection algorithm outperforms Minimum Mean Square Error (MMSE) and Maximal Ratio Combining (MRC) detection techniques.
翻译:下一代无线通信技术有望解决高速移动通信场景中存在的通信可靠性挑战。正交时频空间(OTFS)系统作为一种有效缓解这些问题的方案已被提出。然而,OTFS存在导频开销和多用户复用开销相对较高的问题。针对OTFS框架中的这些缺陷,一种基于离散仿射傅里叶变换的新型调制技术——仿射频分复用(AFDM)应运而生。AFDM通过根据信道时延-多普勒谱调整参数实现全分集,有效解决了上述挑战。因此,AFDM能够达到与OTFS相当的性能水平。鉴于目前关于AFDM检测的研究有限,我们提出了一种低复杂度且高效的消息传递(MP)算法。该算法在利用信道固有稀疏性的同时,实现了联合干扰消除与检测。仿真结果表明,MP检测算法性能优于最小均方误差(MMSE)和最大比合并(MRC)检测技术。