Pinching antennas systems (PASSs) have recently been proposed as a novel flexible-antenna technology. These systems are implemented by attaching low-cost pinching elements to dielectric waveguides. As the direct link is bypassed through waveguides, PASSs can effectively compensate large-scale effects of the wireless channel. This work explores the potential gains of employing PASSs for over-the-air federated learning (OTA-FL). For a PASS-assisted server, we develop a low-complexity algorithmic approach, which jointly tunes the PASS parameters and schedules the mobile devices for minimal energy consumption in OTA-FL. We study the efficiency of the proposed design and compare it against the conventional OTA-FL setting with MIMO server. Numerical experiments demonstrate that using a single-waveguide PASS at the server within a moderately sized area, the required energy for model aggregation is drastically reduced as compared to the case with fully-digital MIMO server. This introduces PASS as a potential technology for energy-efficient distributed learning in next generations of wireless systems.

翻译：夹持天线系统（PASS）作为一种新型柔性天线技术近期被提出。该系统通过在介质波导上附加低成本夹持元件实现。由于直接链路通过波导旁路，PASS能够有效补偿无线信道的大尺度效应。本研究探索了将PASS应用于空中联邦学习（OTA-FL）的潜在增益。针对PASS辅助服务器，我们开发了一种低复杂度算法方法，该方法联合优化PASS参数并调度移动设备，以实现OTA-FL中的能耗最小化。我们分析了所提设计的效率，并将其与采用MIMO服务器的传统OTA-FL配置进行对比。数值实验表明，在中等规模区域内，服务器采用单波导PASS时，模型聚合所需能量相比全数字MIMO服务器方案显著降低。这揭示了PASS作为下一代无线系统中节能分布式学习潜在技术的应用前景。