Programmable wireless environments (PWEs) have emerged as a key paradigm for next-generation communication networks, aiming to transform wireless propagation from an uncontrollable phenomenon into a reconfigurable process that can adapt to diverse service requirements. In this framework, pinching-antenna systems (PASs) have recently been proposed as a promising enabling technology, as they allow the radiation location and effective propagation distance to be adjusted by selectively exciting radiating points along a dielectric waveguide. However, most existing studies on PASs rely on the idealized assumption that pinching-antenna (PA) positions can be continuously adjusted along the waveguide, while realistically only a finite set of pinching locations is available. Motivated by this, this paper analyzes the performance of two-state PASs, where the PA positions are fixed and only their activation state can be controlled. By explicitly accounting for the spatial discreteness of the available pinching points, closed-form analytical expressions for the outage probability and the ergodic achievable data rate are derived. In addition, we introduce the pinching discretization efficiency to quantify the performance gap between discrete and continuous pinching configurations, enabling a direct assessment of the number of PAs required to approximate the ideal continuous case. Finally, numerical results validate the analytical framework and show that near-continuous performance can be achieved with a limited number of PAs, offering useful insights for the design and deployment of PASs in PWEs.

翻译：可编程无线环境已成为下一代通信网络的关键范式，旨在将无线传播从不可控现象转变为可适应多样化服务需求的可重构过程。在此框架下，夹持天线系统最近被提出作为一种有前景的使能技术，因其能够通过选择性激发介质波导上的辐射点来调整辐射位置与有效传播距离。然而，现有关于夹持天线系统的研究大多基于理想化假设，即夹持天线位置可沿波导连续调节，而实际系统中仅存在有限个夹持位置。基于此，本文分析了双态夹持天线系统的性能，其中夹持天线位置固定，仅能控制其激活状态。通过显式考虑可用夹持点的空间离散性，推导出了中断概率与遍历可达数据速率的闭式解析表达式。此外，我们引入夹持离散化效率来量化离散与连续夹持配置之间的性能差距，从而能够直接评估逼近理想连续情形所需的夹持天线数量。最后，数值结果验证了分析框架，并表明通过有限数量的夹持天线即可实现接近连续的性能，为可编程无线环境中夹持天线系统的设计与部署提供了重要参考。