This paper exploits the dynamic features of wireless propagation environments as the basis for a new multiple access technique, termed environment division multiple access (EDMA). In particular, with the proposed pinching-antenna-assisted EDMA, the multi-user propagation environment is intelligently reconfigured to improve signal strength at intended receivers and simultaneously suppress multiple-access interference, without requiring complex signal processing, e.g., precoding, beamforming, or multi-user detection. The key to creating a favorable propagation environment is to utilize the capability of pinching antennas to reconfigure line-of-sight (LoS) links, e.g., pinching antennas are placed at specific locations, such that interference links are blocked on purpose. Based on a straightforward choice of pinching-antenna locations, the ergodic sum-rate gain of EDMA over conventional multiple access and the probability that EDMA achieves a larger instantaneous sum rate than the considered benchmarking scheme are derived in closed form. The obtained analytical results demonstrate the significant potential of EDMA for supporting multi-user communications. Furthermore, pinching antenna location optimization is also investigated, since the locations of pinching antennas are critical for reconfiguring LoS links and large-scale path losses. Two low-complexity algorithms are developed for uplink and downlink transmission, respectively, and simulation results are provided to show their optimality in comparison to exhaustive searches.
翻译:本文利用无线传播环境的动态特性,提出了一种新的多址接入技术,称为环境分割多址接入(EDMA)。具体而言,通过所提出的夹持天线辅助EDMA,多用户传播环境被智能重构,以增强目标接收端的信号强度,同时抑制多址干扰,无需复杂的信号处理(如预编码、波束成形或多用户检测)。创建有利传播环境的关键在于利用夹持天线重构视距(LoS)链路的能力,例如将夹持天线置于特定位置,以有意阻断干扰链路。基于对夹持天线位置的直观选择,本文推导了EDMA相对于传统多址接入的遍历和速率增益的闭式表达式,以及EDMA实现比基准方案更高瞬时和速率的概率。所得分析结果证明了EDMA在支持多用户通信方面的巨大潜力。此外,由于夹持天线位置对重构LoS链路和大尺度路径损耗至关重要,本文还研究了夹持天线位置优化问题。分别针对上行链路和下行链路传输开发了两种低复杂度算法,并通过仿真结果与穷举搜索对比验证了其最优性。