标题： OFDM-PASS：针对夹子天线系统的频率选择性建模与分析 显示英文标题

标题： OFDM-PASS: Frequency-Selective Modeling and Analysis for Pinching-Antenna Systems

摘要： pinching 天线系统（PASS），利用介电波导实现可调谐天线部署，为创建可控视距链路提供了新的机会。 本文首次研究了PASS与正交频分复用（OFDM）的集成，以确保它们的兼容性，并探索PASS固有的频率选择特性。 首先，基于波导的电磁兼容建模和耦合模式理论提出了一个端到端的信道模型，用于OFDM PASS，该模型包括与频率相关的波导色散和天线耦合效应。 此外，揭示了OFDM 循环前缀（CP）开销对工作频率接近波导截止频率的依赖关系。 此外，本文评估了一种基于路径损耗最小化的近似pinching天线位置策略，在这种策略下得出了宽带场景中子载波间的相位错位效应。 数值结果显示：1）OFDM PASS中的频率选择效应导致子载波可达速率出现显著变化，强调了在波导截止频率以上运行对于有效通信的必要性；2）频率无关的pinching天线位置近似会导致显著的相位错位，尤其是在带宽较宽和阵列尺寸较大时；3）当运行在接近截止频率附近时，波导色散要求较大的CP开销，严重影响OFDM PASS的频谱效率。 显示英文摘要

摘要： Pinching antenna systems (PASS), which utilize dielectric waveguides for adaptable antenna deployment, offer novel opportunities to create controllable line-of-sight links. This letter is the first to investigate the integration of PASS with orthogonal frequency division multiplexing (OFDM) to ensure their compatibility and to explore the frequency-selective behavior inherent to PASS. First, an end-to-end channel model is proposed for OFDM PASS based on electromagnetic-compliant modeling of waveguides and coupled-mode theory, which includes frequency-dependent waveguide dispersion and antenna coupling effect. Furthermore, a critical dependence of the OFDM cyclic prefix (CP) overhead on the proximity of the operating frequency to the waveguide cutoff is revealed. Moreover, this letter evaluates an approximate pinching antenna location strategy based on path loss minimization, from which the phase misalignment effect across subcarriers in wideband scenarios is derived. Numerical results show that: 1) frequency-selective effects in OFDM PASS lead to substantial variations in subcarrier achievable rates, highlighting the necessity of operating above the waveguide cutoff frequency for effective communication; 2) frequency-independent pinching antenna location approximation incurs significant phase misalignment, particularly for wider bandwidths and larger array sizes; and 3) waveguide dispersion mandates considerable CP overhead when operating near the cutoff frequency, severely impacting the spectral efficiency of OFDM PASS.