The move to next-generation wireless communications with extremely large-scale antenna arrays (ELAAs) brings the communications into the radiative near-field (RNF) region, where distance-aware focusing is feasible. However, high-frequency RNF links are highly vulnerable to blockage in indoor environments dominated by half-space obstacles (walls, corners) that create knife-edge shadows. Conventional near-field focused beams offer high gain in line-of-sight (LoS) scenarios but suffer from severe energy truncation and effective-rank collapse in shadowed regions, making hardware remedies such as reconfigurable intelligent surfaces (RIS) impractical. We propose a beamforming strategy that exploits the auto-bending property of Airy beams to mitigate half-space blockage without additional hardware. The Airy beam is designed to ``ride'' the diffraction edge, accelerating its main lobe into the shadow to restore connectivity. Our contributions are threefold: (i) a Green's function-based RNF multi-user channel model that analytically reveals singular-value collapse behind knife-edge obstacles; (ii) an Airy analog beamforming scheme that optimizes the bending trajectory to recover the effective channel rank; and (iii) an Airy null-steering method that aligns oscillatory nulls with bright-region users to suppress interference in mixed shadow/bright scenarios. Simulations show that the proposed edge-riding Airy strategy achieves an SNR improvement of over 20 dB and restores full-rank connectivity in shadowed links compared to conventional RNF focusing, virtually eliminating outage in geometric shadows and increasing multi-user spectral efficiency by approximately 35\% under typical indoor ELAA configurations. These results demonstrate robust RNF multi-user access in half-space blockage scenarios without relying on RIS.

翻译：向采用超大规模天线阵列（ELAA）的下一代无线通信演进，将通信带入辐射近场（RNF）区域，使得基于距离的聚焦成为可能。然而，在室内环境中，高频RNF链路极易受到以半空间障碍物（墙壁、角落）为主的遮挡影响，这些障碍物会产生刀锋边缘阴影。传统的近场聚焦波束在视距（LoS）场景下能提供高增益，但在阴影区域会遭受严重的能量截断和有效秩崩塌，使得可重构智能表面（RIS）等硬件补救措施不切实际。我们提出了一种利用艾里光束自弯曲特性来缓解半空间遮挡的波束成形策略，无需额外硬件。该艾里光束被设计为“沿”衍射边缘传播，使其主瓣加速进入阴影区域以恢复连接。我们的贡献有三方面：（i）基于格林函数的RNF多用户信道模型，该模型解析地揭示了刀锋边缘障碍物背后的奇异值崩塌现象；（ii）一种艾里模拟波束成形方案，通过优化弯曲轨迹来恢复有效信道秩；（iii）一种艾里零陷导向方法，将振荡零陷对准明亮区域用户，以抑制混合阴影/明亮场景下的干扰。仿真结果表明，与传统的RNF聚焦相比，所提出的沿边缘传播艾里策略在阴影链路中实现了超过20 dB的信噪比提升，并恢复了满秩连接性，几乎消除了几何阴影中的中断，并在典型的室内ELAA配置下将多用户频谱效率提高了约35%。这些结果证明了在不依赖RIS的情况下，于半空间遮挡场景中实现鲁棒的RNF多用户接入。